• Clinical and Experimental Pediatrics
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• v.45 no.4
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• pp.505-511
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• 2002

Purpose : Mean platelet volume(MPV) and platelet distribution width(PDW) are useful parameters in evaluating disorders of platelets. In cases with idiopathic thrombocytopenic purpura(ITP), they change as platelet count increases. In this study, we compared the values of MPV and PDW in ITP patients at diagnosis with those of normal children. We also studied whether the early changes in MPV may predict the clinical course. Methods : From December 1995 to May 2001, 71 patients with ITP were admitted to Ajou University Hospital. They were treated with IVIg 400 mg/kg for five days and MPV, PDW, platelet count were analysed. Normal control group(n=38) was compared. The study group was divided into acute and chronic forms, and also divided into group A, good early responders whose platelets increased more than $100,000/{\mu}L$ within 5 days and group B who did not. Results : Mean value of MPV at diagnosis in ITP patients was lower than the normal control group(P<0.05). In group A, MPV was abruptly increased on the first day after IVIg and then started to decrease. But in group B, MPV was steadily increased until the fourth day after IVIg. In the normal control group, there were inverse correlations between platelet count and MPV(r=-0.415, P<0.05), but in ITP patients, there were positive relationships between platelet count and MPV(r=0.646, P<0.05) at diagnosis. Conclusions : MPV at diagnosis of ITP was lower than the normal control. MPV and PDW could not predict the course of ITP patients, but MPV could distinguish good early responders. More research is needed to find out the reasons of decreased MPV at diagnosis of ITP.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.134-146
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• 2023

Phytophthora root rot (PRR) is a major soybean disease caused by an oomycete, Phytophthora sojae. PRR can be severe in poorly drained fields or wet soils. The disease management primarily relies on resistance genes called Rps (resistance to P. sojae). This study aimed to identify resistance loci associated with resistance to P. sojae isolate 40468 in Daepung × CheonAl recombinant inbred line (RIL) population. CheonAl is resistant to the isolate, while Daepung is generally susceptible. We genotyped the parents and RIL population via high-throughput single nucleotide polymorphism genotyping and constructed a set of genetic maps. The presence or absence of resistance to P. sojae was evaluated via hypocotyl inoculation technique, and phenotypic distribution fit to a ratio of 1:1 (R:S) (χ² = 0.57, p = 0.75), indicating single gene mediated inheritance. Single-marker association and the linkage analysis identified a highly significant genomic region of 55.9~56.4 megabase pairs on chromosome 18 that explained ~98% of phenotypic variance. Many previous studies have reported several Rps genes in this region, and also it contains nine genes that are annotated to code leucine-rich repeat or serine/threonine kinase within the approximate 500 kilobase pairs interval based on the reference genome database. CheonAl is the first domestic soybean genotype characterized for resistance against P. sojae isolate 40468. Therefore, CheonAl could be a valuable genetic source for breeding resistance to P. sojae.