Genetic diversity of the rice bean (Vigna umbellata) genepool as assessed by SSR markers.

The genetic diversity of 472 rice bean accessions (388 cultivated and 84 wild) from 16 Asian countries was evaluated by 13 simple sequence repeat (SSR) markers. In total, 168 alleles were detected, and the numbers of alleles in cultivated and wild accessions were 129 and 132, respectively. The gene diversity in cultivated populations (0.565) was about 83% of that for wild (0.678) populations. Cultivated populations from Vietnam, Myanmar, Nepal, and India had the highest gene diversity (>0.5). East Asian accessions formed a distinct genepool. Indonesian cultivated accessions showed high genetic divergence from other cultivated populations and had the most similar genetic structure to wild accessions. In Nepalese cultivated accessions, many accessions from western regions were quite distinct from others and formed a specific group. These Nepalese accessions could be considered a unique gene source for rice bean breeding. In contrast, eastern Nepalese accessions showed an SSR profile similar to that of Southeast Asian rice beans. The present study represents the first comprehensive SSR analysis in cultivated and wild rice bean germplasm and clarifies geographical distribution of genetic profile that might be used to broaden the genetic base of currently grown rice bean cultivars.

Genetic diversity of the azuki bean (Vigna angularis (Willd.) Ohwi & Ohashi) gene pool as assessed by SSR markers.

To facilitate the wider use of genetic resources including newly collected cultivated and wild azuki bean germplasm, the genetic diversity of the azuki bean complex, based on 13 simple sequence repeat (SSR) primers, was evaluated and a core collection was developed using 616 accessions originating from 8 Asian countries. Wild germplasm from Japan was highly diverse and represented much of the allelic variation found in cultivated germplasm. The SSR results together with recent archaeobotanical evidence support the view that Japan is one center of domestication of azuki bean, at least for the northeast Asian azuki bean. Cultivated azuki beans from China, Korea, and Japan were the most diverse and were genetically distinct from each other, suggesting a long and relatively isolated history of cultivation in each country. Cultivated azuki beans from eastern Nepal and Bhutan were similar to each other and quite distinct from others. For two primers, most eastern Nepalese and Bhutanese cultivated accessions had null alleles. In addition, wild accessions from the Yangtze River region of China and the Himalayan region had a null allele for one or the other of these primers. Whether the distinct diversity of azuki bean in the Himalayan region is due to introgression or separate domestication events requires further study. In contrast, western Nepalese azuki beans showed an SSR profile similar to that of Chinese azuki beans. The genetic distinctness of cultivated azuki beans from Vietnam has been revealed for the first time. The specific alleles indicate that Vietnamese azuki beans have been cultivated in isolation from Chinese azuki beans for a long time. Wild germplasm from the Himalayan region showed the highest level of variation. Based on the results, Himalayan germplasm could be considered a novel gene source for azuki bean breeding. A comparison with mungbean SSR analysis revealed that the mean gene diversity of cultivated azuki bean (0.74) was much higher than that of cultivated mungbean (0.41). The reduction in gene diversity due to domestication, the domestication bottleneck, in azuki bean is not strong compared with that in mungbean.

Development of a black gram [Vigna mungo (L.) Hepper] linkage map and its comparison with an azuki bean [Vigna angularis (Willd.) Ohwi and Ohashi] linkage map.

The Asian Vigna group of grain legumes consists of six domesticated species, among them black gram is widely grown in South Asia and to a lesser extent in Southeast Asia. We report the first genetic linkage map of black gram [Vigna mungo (L.) Hepper], constructed using a BC(1)F(1) population consisting of 180 individuals. The BC(1)F(1) population was analyzed in 61 SSR primer pairs, 56 RFLP probes, 27 AFLP loci and 1 morphological marker. About 148 marker loci could be assigned to the 11 linkage groups, which correspond to the haploid chromosome number of black gram. The linkage groups cover a total of 783 cM of the black gram genome. The number of markers per linkage group ranges from 6 to 23. The average distance between adjacent markers varied from 3.5 to 9.3 cM. The results of comparative genome mapping between black gram and azuki bean show that the linkage order of markers is highly conserved. However, inversions, insertions, deletions/duplications and a translocation were detected between the black gram and azuki bean linkage maps. The marker order on parts of linkage groups 1, 2 and 5 is reversed between the two species. One region on black gram linkage group 10 appears to correspond to part of azuki bean linkage group 1. The present study suggests that the azuki bean SSR markers can be widely used for Asian Vigna species and the black gram genetic linkage map will assist in improvement of this crop.

A genetic linkage map for azuki bean [Vigna angularis (Willd.) Ohwi & Ohashi].

To make progress in genome analysis of azuki bean (Vigna angularis) a genetic linkage map was constructed from a backcross population of (V. nepalensis x V. angularis) x V.angularis consisting of 187 individuals. A total of 486 markers-205 simple sequence repeats (SSRs), 187 amplified fragment length polymorphisms (AFLPs) and 94 restriction fragment length polymorphisms (RFLPs) -were mapped onto 11 linkage groups corresponding to the haploid chromosome number of azuki bean. This map spans a total length of 832.1 cM with an average marker distance of 1.85 cM and is the most saturated map for a Vigna species to date. In addition, RFLP markers from other legumes facilitated finding several orthologous linkage groups based on previously published RFLP linkage maps. Most SSR primers that have been developed from SSR-enriched libraries detected a single locus. The SSR loci identified are distributed throughout the azuki bean genome. This moderately dense linkage map equipped with many SSR markers will be useful for mapping a range of useful traits such as those related to domestication and stress resistance. The mapping population will be used to develop advanced backcross lines for high resolution QTL mapping of these traits.

[Double minute chromosomes (DMs) in a case of acute myelomonocytic leukemia].

A 71-year old male was admitted to our hospital because of general malaise and fever. Peripheral blood showed Hb 8.1 g/dl, platelet 7.0 X 10(4)/microliters, and WBC 18.100/microliters with 64% leukemic cells. Bone marrow showed normocellularity with 73.4% leukemic cells. They were positive for peroxidase and alpha-naphthyl butyrate esterase stainings. Serum and urine lysozyme levels were elevated. He was diagnosed as having acute myelomonocytic leukemia (M 4 in FAB classification). Chromosome analysis of bone marrow cells showed 45, XY, -17, t (9; 17) (q22; p13) and double minute chromosomes (DMs) were observed in the 50 cells analyzed. A complete remission (CR) was obtained by DCMP regimen, but he relapsed as acute monocytic leukemia (M 5 b in FAB classification) and died 5 months after diagnosis. DMs appear to be rare in acute leukemia and the clinical and etiologic implications of DMs are discussed.

[Complete remission obtained in refractory acute lymphocytic leukemia using high-dose cytosine arabinoside combined with low-dose L-asparaginase].

A 41-year-old male was diagnosed as acute lymphocytic leukemia (ALL) in November, 1982 and partial remission was obtained by a combination chemotherapy of LVP, DVP ABOP and VAMP. In January, 1983, peripheral blood showed an increasing number of leukemic cells and he was readmitted to our hospital. WBC count in the peripheral blood was 13,200/mm3 and an 82% ratio of leukemic cells was observed. Bone marrow aspiration showed a hypercellularity of 89.4% leukemic cells. High-dose Ara-C therapy was started at a dose of 3 g/m2 i.v. every 12 hours for 6 days. Leukemic cells in peripheral blood were rapidly decreased in number, and the nucleated cell count of bone marrow was also reduced after 3 weeks of treatment, however 95% of leukemic cells remained. Low-dose L-asparaginase was then supplemented at a dose of 2000 U for 3 days, and 2 months later complete remission was achieved. The side effects associated with this high-dose Ara-C therapy were nausea, vomiting, diarrhea, fever and conjunctivitis, although these were tolerable. These observations suggest that high-dose Ara-C combined with L-asparaginase should be added to the treatment of leukemia which is refractory to conventional chemotherapy.

Micronuclei in human bone-marrow cells: evaluation of the micronucleus test using human leukemia patients treated with antileukemic agents.

The relevance of the micronucleus test to human studies was investigated by using bone marrow from leukemic patients treated with antileukemic drugs. The median incidence of micronucleated erythrocytes and erythroblasts, respectively, increased from control values of 0.04 and 0.72% to 0.29 and 25.3% in leukemic cases; and the frequency of micronucleated erythroblasts was inevitably higher than the control value in cases that showed a higher frequency of micronucleated erythrocytes, but the reverse was not true. These results indicate that almost the same changes of micronucleus formation that are observed in the mouse micronucleus test are produced in human bone marrow by antileukemic drugs--mutagenic compounds--and, if the micronuclei were scored restrictively in erythroblasts, the application of the micronucleus test to human bone marrow would be reasonable.

Conformational study of the basic proline-rich polypeptides from human parotid saliva.

The conformational study of two basic proline-rich polypeptides from human parotid saliva, P--D and P--E of known primary structures, was performed by CD and 1H--n.m.r. spectra measurements. These polypeptides contain consecutive sequences of five prolyl residues in their amino acid sequences. The troughs in CD spectra of P--D and P--E were found at 202 and 201 nm, respectively. These wavelengths were different from the value of 206 nm of poly-L-proline form II conformation. In spite of this, the existence of poly-L-proline form II conformation was suggested in the structure of P--D, because the trough for a fragmental peptide of P--D containing five consecutive prolyl residues was found at 204 nm. No remarkable change was detected in CD and 1H--n.m.r. spectra of P--D and P--E in the range of pH 3.0-11.0. The result suggests that no folding of polypeptide which might be affected by ionic interaction exists in its structure.

Conformational study of the salivary proline-rich polypeptides.

The conformational study of three proline-rich polypeptides of human whole saliva, with known primary structures, was performed by CD and 1H-n.m.r. spectra measurements. All these polypeptides contained more than four consecutive prolyl residues in their amino acid sequences. The occurrence of the poly-L-proline form II conformation in their structures was demonstrated with two of these polypeptides. The continuous prolyl residues in the third was suggested to take the same structure as the others.

[A case of malignant melanoma responded to chemotherapy including DTIC and local injection of OK-432].

A 33-year-old woman with malignant melanoma well responded to a chemotherapy including DTIC, ACNU, and VCR, and intralegional injection of OK-432. Four years prior to admission, a lentigo of 5 mm diameter at her left frontal chest was found, but, histological examination resulted in no distinctly malignant findings. In November 1979, multiple subcutaneous tumors appeared over posterior surface of the chest and left axillar region, which were gradually increasing in number and size, then she was admitted to our hospital in June, 1980. Biopsy of subcutaneous tumors revealed a malignant melanoma and its metastasis to skin. Immunochemotherapy was started immediately based upon this diagnoses. The patient received 100mg DTIC i.v. for 4 days, 100mg ACNU i.v. for one day and 1 mg VCR i.v. for one day. OK-432 was locally injected into some tumors as an immunotherapy. On completion of the third course of chemotherapy, all subcutaneous tumors were decreased in size, especially the tumors injected with OK-432. However, patient didn't respond to a repeated chemotherapy, thereafter malignant melanoma was metasized to uterus and peritoneum in May, 1981, and she died in September, 1981. Major side effects of this chemotherapy were nausea and mild transient leukocytopenia. The combination of chemotherapy including DTIC and local injection of OK-432 appeared to be effective for malignant melanoma.