Analysis of DNA sequence polymorphism at the cMWG699 locus reveals phylogenetic relationships and allopolyploidy within Hordeum murinum subspecies.

Hordeum murinum L. is one of the most widely distributed species in the genus Hordeum. This species is composed of three subspecies with three ploidy levels, namely subsp. glaucum (2x=14), subsp. murinum (4x=28) and subsp. leporinum (4x=28, 6x=42). These three subspecies are morphologically similar and are frequently referred to as the 'murinum complex'. Although many cytological studies suggest that the murinum complex is allopolyploid, one inter-specific hybridization study suggested that it is autopolyploid. The goals of the present study are to identify nucleotide variation in the cMWG699 locus in the polyploid genomes of the murinum complex, to conduct molecular phylogenetic analysis of this locus, and to clarify the allo- versus auto-polyploidy status of the murinum complex. For this purpose, PCR-RFLP analysis was conducted with HhaI and SspI restriction enzymes on 80 H. murinum accessions. Single enzyme digestion data revealed polymorphism between diploid and polyploids, and double-digestion revealed polymorphism between tetra- and hexaploids. The nucleotide sequences of clones clearly show that polyploid murinum species are allopolyploid. In addition, DNA sequence analysis indicated that one donor of the tetraploid was subsp. glaucum (2x), as has been suggested previously by cytological studies. The other diploid donors were not identified, but at least one group of sequences common to 4x and 6x genomes (namely clonetype B) was highly diverged from 2x subsp. glaucum. The two tetraploid subspecies, 4x subsp. murinum and 4x subsp. leporinum, had identical DNA sequences, suggesting that these two subspecies are not differentiated at the cMWG699 locus.

Analysis of the barley chromosome 2 region containing the six-rowed spike gene vrs1 reveals a breakdown of rice-barley micro collinearity by a transposition.

In cultivated barley (Hordeum vulgare ssp. vulgare), six-rowed spikes produce three times as many seeds per spike as do two-rowed spikes. The determinant of this trait is the Mendelian gene vrs1, located on chromosome 2H, which is syntenous with rice (Oryza sativa) chromosomes 4 and 7. We exploited barley-rice micro-synteny to increase marker density in the vrs1 region as a prelude to its map-based cloning. The rice genomic sequence, covering a 980 kb contig, identified barley ESTs linked to vrs1. A high level of conservation of gene sequence was obtained between barley chromosome 2H and rice chromosome 4. A total of 22 EST-based STS markers were placed within the target region, and the linear order of these markers in barley and rice was identical. The genetic window containing vrs1 was narrowed from 0.5 to 0.06 cM, which facilitated covering the vrs1 region by a 518 kb barley BAC contig. An analysis of the contig sequence revealed that a rice Vrs1 orthologue is present on chromosome 7, suggesting a transposition of the chromosomal segment containing Vrs1 within barley chromosome 2H. The breakdown of micro-collinearity illustrates the limitations of synteny cloning, and stresses the importance of implementing genomic studies directly in the target species.

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.

Malignant fibrous histiocytoma of the spleen: report of a case and literature review.

There is a marked paucity of reports on malignant fibrous histiocytoma (MFH) of the spleen in the literature, and there are no previous reports of its color Doppler sonographic (US) and contrast-enhanced US findings. We report on an 82-year-old male with splenic MFH (inflammatory subtype), with an emphasis on color Doppler and contrast-enhanced US findings.

Gallbladder adenoma: report of a case with emphasis on contrast-enhanced US findings.

There is a marked paucity of contrast-enhanced ultrasound (US) findings of gallbladder disease in the literature, and there is only one previous case of gallbladder adenoma. We report such a case. US showed a 2-cm polypoid lesion at the gallbladder body. Color Doppler US showed the hypervascular nature of the lesion, and contrast-enhanced US revealed the lesion to be homogeneously enhanced, suggesting that the lesion was composed of the same pathology. The lesion was surgically resected, and was found to be an adenoma without cancer foci. This case suggests that contrast-enhanced US is an effective tool in diagnosing a gallbladder adenoma.

Duodenal adenoma with production of massive mucus: report of a case with emphasis on US findings.

Duodenal adenoma with massive mucus production is very rare. We report such a case. Ultrasonography (US) showed the presence of massive mucus, and contrast- enhanced US revealed the thickened wall to be homogeneously enhanced, suggesting that the lesion was composed of the same pathology. The US results were confirmed histologically by endoscopically guided biopsy. Thus, contrast-enhanced US helps determine the biopsy point and determine good diagnostic strategies.

Malignant paraganglioma draining into the main portal vein.

Abdominal paraganglioma is a relatively rare tumor, and there have been no previous reports describing its contrast-enhanced ultrasonographic findings. We report a case of a lesion of unknown origin incidentally detected by ultrasound in the right upper abdomen. The lesion was markedly hypervascular and contrast-enhanced ultrasonogram showed it to be communicating with the portal vein. This communication was then confirmed by angiogram. Such an arteriovenous communication through paraganglioma has been recently reported, and a diagnosis of a paraganglioma should be considered when contrast-enhanced ultrasonogram shows a solid mass of unknown origin draining directly into the venous system.

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.

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.

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.

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.

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.

Differentiation of exudate from transudate ascites by Doppler sonography.

BACKGROUND: We investigated whether the addition of Doppler sonography (US) increases the diagnostic confidence of US for estimating the nature of ascites. METHODS: Of the 127 cases reviewed in this study, there were 42 cases of transudate and 85 of exudate ascites. We reviewed the US, power Doppler, and pulsed Doppler images of these cases. RESULTS: With US, the transudate ascites was imaged as free of echo in 38 of 42 cases (90.5%). The exudate ascites was imaged as free of echo in 22 of 85 cases (25.9%) and with internal echo spots in 63 of 85 cases (74.1%). With Doppler US, we obtained distinct pulsed signals from the transudate ascites in only two of 36 cases (5.6%). In contrast, we obtained distinct Doppler signals from the exudate ascites in 66 of 79 cases (83.5%). Those 66 cases included 16 of the 22 cases with echo-free ascites. CONCLUSION: The presence or absence of echo spots within the ascites helped differentiate transudate from exudate ascites, as reported in the literature. However, the addition of Doppler US contributed to the differentiation of echo-free exudate (Doppler signals present) from echo-free transudate (Doppler signals absent) ascites.

Appendiceal mucocele: sonographic findings.

BACKGROUND: Appendiceal mucocele (AM) is a relatively rare disease, and its sonograms (US) have not been sufficiently analyzed. METHODS: We studied the US findings of five patients with AM, with special attention to AM size, shape, internal echoes, and the mode of back echoes. RESULTS: All five cases showed an elongated mass in the lower right abdomen. Internal echoes were present in all cases and M-mode US confirmed the movement of those echoes. The echogenecity of the lesion changed according to the frequency of the transducer used. Only one case showed posterior echo enhancement, and no case showed lateral shadowing. CONCLUSION: AM appears as an elongated echo-poor mass without posterior echo enhancement. The cyst wall is less distinct than what one would expect for a cyst. When encountering such a mass in the lower right abdomen, one should strongly suspect an AM. In such cases, appropriate diagnostic and therapeutic strategies are especially necessary to prevent rupture that results in development of pseudomyxoma peritonei.

Dilatation of the cystic duct in patients with obstructive jaundice.

BACKGROUND: It is well known that obstructive jaundice causes biliary dilatation, but sonographic (US) findings of the cystic duct in patients with obstructive jaundice are rarely reported. METHODS: We reviewed US findings in 25 such patients. RESULTS: US findings of dilated cystic duct could be divided roughly into two patterns: tortuous and tubular. The former pattern was a tortuously dilated cystic duct arising from the gallbladder neck, running predominantly deeply, turning anteromedially, and then joining the posterior face of the common hepatic duct. The latter pattern was a straight dilated cystic duct running parallel with the common hepatic duct, giving the appearance of a septated bile duct. CONCLUSION: A better understanding of the US findings of dilated cystic duct translates into improved biliary US diagnosis.

Retroperitoneal cyst: sonographic findings.

BACKGROUND: Retroperitoneal cyst (RC) is a relatively rare disease, and its sonographic (US) findings have not been analyzed sufficiently. METHODS: We studied US findings of five patients with RC, with special attention to location, size, shape, internal echoes, the presence or absence of lateral shadowing, and the mode of back echoes. RESULTS: In all cases, the cyst was situated behind (four cases) or lateral to (one case) the pancreas: behind or lateral to the pancreatic head in two cases, behind the pancreatic body in one case, and behind the pancreatic tail in two cases. Four cases showed a round mass (three cases) or multiple round mass (one case). Internal echoes were present in those cases and showed a "pseudo-solid" pattern. In those cases, M-mode US confirmed the movement of those internal echoes. In the remaining case, the lesion was imaged as an irregularly shaped multilocular mass. No case showed posterior echo enhancement, and no case showed lateral shadowing. No blood flow signals from the lesion were seen. CONCLUSION: Unlike ordinary cysts, RC usually is imaged as a round mass behind the pancreas, with dense internal echoes without lateral shadowing or posterior echo enhancement, which presents a "pseudo-solid" pattern. A diagnosis of RC should be considered when encountering a mass with such US findings.

Accessory hepatic duct: sonographic findings.

Accessory hepatic ducts are relatively rare biliary anomalies. They have been reported only sporadically, and very few reports have described their sonographic (US) findings. Our experience with two such cases suggested that a diagnosis of an accessory hepatic duct should be considered when US shows a fine tubular structure or an anechoic or hypoechoic oval mass with acoustic shadowing at the level between the hepatic hilus and the common bile duct. A good knowledge of the US findings will determine the diagnostic and therapeutic strategies.

Abdominal lymphoma: differentiation from pancreatic carcinoma with Doppler US.

BACKGROUND: Marked lymphadenopathy around the pancreas due to lymphoma (abdominal lymphoma) occasionally can mimic a total pancreatic carcinoma on ultrasonography (US). We investigated whether US and color Doppler US allowed differentiation between those pathologies. METHODS: We analyzed the US and color Doppler results of 12 cases of abdominal peripancreatic lymphoma and 21 cases of total pancreatic carcinoma. RESULTS: With regard to shape, echogenicity of the lesion, and mode of vascular involvement, there was no difference between groups. With regard to maximal velocities and resistive indices of the involved vessels, there was no difference between groups. However, the presence of turbulent flows in the involved vessels was seen exclusively in the pancreatic carcinoma group. CONCLUSION: The presence or absence of turbulent flow in the involved vessels is a very important finding for differentiating abdominal lymphomas from total pancreatic carcinomas.

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.

Emphysematous cholecystitis: sonographic findings.

BACKGROUND: Emphysematous cholecystitis (EC) is a rare but life-threatening complication of acute cholecystitis, and an early diagnosis is required to prevent delay in patient management. Because sonography (US) is the first choice for diagnosing gallbladder diseases, US findings of EC should be understood more precisely. METHODS: We reviewed US findings of 11 surgically proven cases of EC (with small amounts of gas in three cases and large amounts in eight cases) and compared those with patients' clinical data. RESULTS: (1) In cases with small amounts of gas, US showed an echogenic line with a distinct ring-down artifact or a "powder snow-like" speckled posterior echo. (2) In cases with large amounts of gas, US showed a wide spiculated echogenic band with a powder snow-like speckled posterior echo or a speckled acoustic shadowing. In all cases, the presence of gas prevented visualization of the gallbladder wall. (3) US did not differentiate gas localized to the gallbladder wall and gas extending to the surrounding hepatic tissue. (4) Two diabetic cases showed gas throughout the intrahepatic bile ducts. In those cases, the time from diagnosis to recovery was relatively long. CONCLUSION: Our series showed some characteristic US patterns of EC. A good understanding of its US findings and appropriate emergent management will reduce the serious morbidity and mortality rates caused by EC.