Mapping of QTLs controlling epicotyl length in adzuki bean (Vigna angularis).

Epicotyl length (ECL) of adzuki bean (Vigna angularis) affects the efficiency of mechanized weeding and harvest. The present study investigated the genetic factors controlling ECL. An F2 population derived from a cross between the breeding line 'Tokei1121' (T1121, long epicotyls) and the cultivar 'Erimo167' (common epicotyls) was phenotyped for ECL and genotyped using simple sequence repeats (SSRs) and single-nucleotide polymorphism (SNP) markers. A molecular linkage map was generated and fifty-two segregating markers, including 27 SSRs and 25 SNPs, were located on seven linkage groups (LGs) at a LOD threshold value of 3.0. Four quantitative trait loci (QTLs) for ECL, with LOD scores of 4.0, 3.4, 4.8 and 6.4, were identified on LGs 2, 4, 7 and 10, respectively; together, these four QTLs accounted for 49.3% of the phenotypic variance. The segregation patterns observed in F5 residual heterozygous lines at qECL10 revealed that a single recessive gene derived from T1121 contributed to the longer ECL phenotype. Using five insertion and deletion markers, this gene was fine mapped to a ~255 kb region near the end of LG10. These findings will facilitate marker-assisted selection for breeding in the adzuki bean and contribute to an understanding of the mechanisms associated with epicotyl elongation.

Rice Stomatal Closure Requires Guard Cell Plasma Membrane ATP-Binding Cassette Transporter RCN1/OsABCG5.

Water stress is one of the major environmental stresses that affect agricultural production worldwide. Water loss from plants occurs primarily through stomatal pores. Here, we report that an Oryza sativa half-size ATP-binding cassette (ABC) subfamily G protein, RCN1/OsABCG5, is involved in stomatal closure mediated by phytohormone abscisic acid (ABA) accumulation in guard cells. We found that the GFP-RCN1/OsABCG5-fusion protein was localized at the plasma membrane in guard cells. The percentage of guard cell pairs containing both ABA and GFP-RCN1/OsABCG5 increased after exogenous ABA treatment, whereas they were co-localized in guard cell pairs regardless of whether exogenous ABA was applied. ABA application resulted in a smaller increase in the percentage of guard cell pairs containing ABA in rcn1 mutant (A684P) and RCN1-RNAi than in wild-type plants. Furthermore, polyethylene glycol (drought stress)-inducible ABA accumulation in guard cells did not occur in rcn1 mutants. Stomata closure mediated by exogenous ABA application was strongly reduced in rcn1 mutants. Finally, rcn1 mutant plants had more rapid water loss from detached leaves than the wild-type plants. These results indicate that in response to drought stress, RCN1/OsABCG5 is involved in accumulation of ABA in guard cells, which is indispensable for stomatal closure.

Rice RCN1/OsABCG5 mutation alters accumulation of essential and nonessential minerals and causes a high Na/K ratio, resulting in a salt-sensitive phenotype.

Mineral balance and salt stress are major factors affecting plant growth and yield. Here, we characterized the effects of rice (Oryza sativa L.) reduced culm number1 (rcn1), encoding a G subfamily ABC transporter (OsABCG5) involved in accumulation of essential and nonessential minerals, the Na/K ratio, and salt tolerance. Reduced potassium and elevated sodium in field-grown plants were evident in rcn1 compared to original line 'Shiokari' and four independent rcn mutants, rcn2, rcn4, rcn5 and rcn6. A high Na/K ratio was evident in the shoots and roots of rcn1 under K starvation and salt stress in hydroponically cultured plants. Downregulation of SKC1/OsHKT1;5 in rcn1 shoots under salt stress demonstrated that normal function of RCN1/OsABCG5 is essential for upregulation of SKC1/OsHKT1;5 under salt stress. The accumulation of various minerals in shoots and roots was also altered in the rcn1 mutant compared to 'Shiokari' under control conditions, potassium starvation, and salt and d-sorbitol treatments. The rcn1 mutation resulted in a salt-sensitive phenotype. We concluded that RCN1/OsABCG5 is a salt tolerance factor that acts via Na/K homeostasis, at least partly by regulation of SKC1/OsHKT1;5 in shoots.

Glucose intolerance is common in Japanese patients with acute coronary syndrome who were not previously diagnosed with diabetes.

OBJECTIVE: Postprandial hyperglycemia has emerged as a new glycometabolic condition associated with an excessive risk for coronary artery disease. We therefore attempted to evaluate the frequency of postchallenge hyperglycemia in patients with acute coronary syndrome (ACS) who were not previously diagnosed to have diabetes and did not have a fasting glucose concentration of > or =7 mmol/l or an HbA(1c) level >6.0%. We further correlated the presence of postchallenge hyperglycemia with the extent of coronary atherosclerosis. RESEARCH DESIGN AND METHODS: In all, 134 consecutive ACS patients who met the above inclusion criteria were studied. An oral glucose tolerance test was performed before discharge. RESULTS: The mean age, fasting glucose, and HbA(1c) were 60 years, 5.15 mmol/l, and 5.4%, respectively. Among ACS patients, impaired glucose tolerance (IGT) and diabetes were found in 50 (37%) and 13 patients (10%), respectively. The homeostasis model assessment for insulin resistance did not differ substantially among the normal glucose tolerance (NGT), IGT, and diabetic groups. Insulinogenic index, however, was lower and the number of stenosed vessels higher in diabetic patients compared with NGT patients. CONCLUSIONS: Postchallenge hyperglycemia, caused primarily by impaired initial insulin secretion, is commonly found in Japanese ACS patients who have not been previously diagnosed with diabetes, and this phenomenon is considered to be associated with advanced coronary atherosclerosis. Therefore, the present study strongly supports the notion that oral glucose tolerance test assessment of postchallenge hyperglycemia is essential to identify any previously undiagnosed diabetes cases among Japanese ACS patients.

Usefulness of a 6 fr right judkins catheter for mechanically extracting a massive intracoronary thrombus from an ectasic right coronary artery: a report on two different cases of thrombectomy.

In order to bail out the slow-flow phenomenon (slow flow) created by a massive thrombus in an ectasic right coronary artery, a thrombus was mechanically extracted with a 6 Fr right Judkins (JR) catheter, which proved to be more useful than a usual thrombectomy using a Rescue PT system catheter (Rescue). In case 1, the Rescue was used in combination with thrombolysis but failed to alleviate the slow flow that was implicated in a large infarction. On the other hand, in case 2, aggressive thrombectomy with a 6 Fr JR catheter with an 8 Fr Amplatz guiding catheter successfully extracted the massive intracoronary thrombus, restoring good coronary flow. Therefore, mechanical extraction with a 6 Fr JR catheter is safe and useful in cases of massive thrombus when diffuse coronary artery ectasia complicates an acute myocardial infarction. In addition, this method should be applicable to cases of acute coronary syndrome with massive thrombus.

Mitral regurgitation disappearance after cibenzoline treatment in a patient with hypertrophic obstructive cardiomyopathy.

Hypertrophic obstructive cardiomyopathy (HOCM), which shows left ventricular outflow pressure gradient (LVPG), is often complicated with mitral regurgitation (MR). We examined a 62-year-old Japanese female with HOCM and MR. Ultrasound echocardiography showed severe MR, asymmetrical septal hypertrophy, systolic anterior movement of the mitral valve anterior leaflet, and left ventricular outflow stenosis. Her LVPG, measured using continuous wave Doppler recording, was 118 mmHg. During heart catheterization, the aortic pressure and left ventricular pressure were simultaneously measured. An intravenous injection of 70 mg cibenzoline decreased the LVPG from 110 mmHg to 16 mmHg. Left ventriculography was performed immediately after the injection and did not show MR. This clearly demonstrates that cibenzoline decreases LVPG in patients with HOCM and also improves the MR that arises from LVPG.