Genome-Wide Association Studies (GWAS) for Yield and Weevil Resistance in Sweet potato (Ipomoea batatas (L.) Lam).

KEY MESSAGE: We apply the GWAS to sweet potato genome, and identified the SNPs associated with yield and weevil resistance. The sweet potato (Ipomoea batatas (L.) Lam) is a highly heterozygous, outcrossing, polyploid species, which presents challenges for genetic analysis. Therefore, we considered that genome-wide association studies (GWAS) may be applied to the study of the sweet potato genome. The yield of two sweet potato varieties [Purple Sweet Lord (PSL) and 90IDN-47] was assessed at two locations (Kumamoto and Okinawa prefectures) in Japan in 2013 and the yield scores were used for GWAS. The results showed that there were several single nucleotide polymorphisms (SNP) above the significance thresholds in PSL; two peaks were detected in Kumamoto and Okinawa on the Ib03-3 and Ib01-4 linkage groups of PSL, respectively. As for 90IDN-47, one relatively high peak was detected in Kumamoto on the Ib13-8 linkage group. Interestingly, although high peaks above significance thresholds were detected in Kumamoto and Okinawa in PSL, the peaks were located in different linkage groups. This result suggests that the genetic regions controlling yield may change in response to environmental conditions. Additionally, we investigated the degree of weevil damage to the plants, which is the greatest problem in sweet potato cultivation in Okinawa. In this experiment, no SNPs were identified above the significance thresholds. However, one relatively high peak was found in the 90IDN-47 genotype, which showed resistance to weevils. On the other hand, one relatively high peak was also detected in the PSL genotype, which showed susceptibility to weevils. These results suggest that two regions could affect weevil resistance and may contain the gene(s) controlling weevil resistance.

Review of major sweetpotato pests in Japan, with information on resistance breeding programs.

Sweetpotato (Ipomoeae batatas (L.) Lam.) is an important food crop affected by several pests throughout the world, especially in tropical, subtropical, and temperate regions. Although Japan is relatively free from many serious sweetpotato pests, some pests, especially soil-borne pathogens, viruses, and insects such as plant-parasitic nematodes and weevils, cause severe damage in Japan. In this review, we describe the current status and management options for sweetpotato pests and diseases in Japan and review research related to sweetpotato breeding that can promote resistance to these problems. Furthermore, we describe methods to evaluate resistance to pests and disease used in sweetpotato breeding at the National Agriculture and Food Research Organization (NARO).

Construction of a linkage map based on retrotransposon insertion polymorphisms in sweetpotato via high-throughput sequencing.

Sweetpotato (Ipomoea batatas L.) is an outcrossing hexaploid species with a large number of chromosomes (2n = 6x = 90). Although sweetpotato is one of the world's most important crops, genetic analysis of the species has been hindered by its genetic complexity combined with the lack of a whole genome sequence. In the present study, we constructed a genetic linkage map based on retrotransposon insertion polymorphisms using a mapping population derived from a cross between 'Purple Sweet Lord' (PSL) and '90IDN-47' cultivars. High-throughput sequencing and subsequent data analyses identified many Rtsp-1 retrotransposon insertion sites, and their allele dosages (simplex, duplex, triplex, or double-simplex) were determined based on segregation ratios in the mapping population. Using a pseudo-testcross strategy, 43 and 47 linkage groups were generated for PSL and 90IDN-47, respectively. Interestingly, most of these insertions (~90%) were present in a simplex manner, indicating their utility for linkage map construction in polyploid species. Additionally, our approach led to savings of time and labor for genotyping. Although the number of markers herein was insufficient for map-based cloning, our trial analysis exhibited the utility of retrotransposon-based markers for linkage map construction in sweetpotato.

Secondary normal pressure hydrocephalus following pituitary apoplexy: A case report.

Background: Although secondary normal pressure hydrocephalus (sNPH) can occur in various central nervous system diseases, there are no reports of sNPH caused by pituitary lesions. Herein, we present a unique case of sNPH caused by pituitary apoplexy. Case Description: A 70-year-old man was transferred to our hospital because of a sudden onset of headache and loss of consciousness. The cerebrospinal fluid (CSF) test showed slightly elevated cell counts and protein levels but a negative CSF culture test. Magnetic resonance imaging showed a dumbbell-like cystic lesion with hemorrhagic change at the sella turcica. From the above, the patient was diagnosed with aseptic meningitis caused by pituitary apoplexy. Pituitary hormone replacement therapy was undertaken, and his symptoms fully improved. However, two months later, he complained of a gait disturbance and incontinence that had gradually appeared. Brain imaging with computed tomography showed no ventricular enlargement compared with initial images, although the lateral ventricles were slightly enlarged. As a CSF drainage test improved his symptoms temporarily, sNPH with possible longstanding overt ventriculomegaly in adults (LOVA) background was suspected. We performed a lumboperitoneal shunt (LPS) placement, which improved his symptoms. Conclusion: This case suggests that sNPH can develop even after a small subarachnoid hemorrhage caused by a pituitary apoplexy in LOVA patients. If the aqueduct of Sylvius is open, sNPH with a LOVA background can be successfully treated with LPS placement.

A rare case of allergic bronchopulmonary mycosis complicating pulmonary pleomorphic carcinoma.

A 72-year-old man with productive cough and wheezing was referred to our institution for a growing mass shadow and central bronchiectasis in the right lower lobe on computed tomography. Based on the symptoms, elevated Aspergillus-specific immunoglobulin E levels, and radiological findings, allergic bronchopulmonary mycosis (ABPM) was suspected according to the Japanese clinical diagnostic criteria. The patient refused bronchoscopic examination, and oral prednisolone (0.5 mg/kg/day) improved the symptoms; however, the mass shadow continued to grow. Subsequently, bronchoscopy revealed mucus plugs and an endobronchial tumour with a whitish surface. The tumour was surgically resected, and the pathological diagnosis was a coexistence of ABPM and pulmonary pleomorphic carcinoma. To the best of our knowledge, this is the first case of ABPM developing at the site of pulmonary pleomorphic carcinoma. Careful bronchoscopic examinations and histopathological evaluations of the surgical specimen led to a prompt and accurate diagnosis.

DFT study of a 5-endo-trig-type cyclization of 3-alkenoic acids by using Pd-spiro-bis(isoxazoline) as catalyst: importance of the rigid spiro framework for both selectivity and reactivity.

The reaction pathway of an enantioselective 5-endo-trig-type cyclization of 3-alkenoic acids catalyzed by a chiral palladium-spiro-bis(isoxazoline) complex, Pd-SPRIX, has been studied by density functional theory calculations. The most plausible pathway involves intramolecular nucleophilic attack of the carboxylate moiety on the C=C double bond activated by Pd-SPRIX and ß-H elimination from the resulting organopalladium intermediate. The enantioselectivity was determined in the cyclization step through the formation of a π-olefin complex, in which one of the two enantiofaces of the olefin moiety was selected. The ß-H elimination occurs via a seven-membered cyclic structure in which the acetate ligand plays a key role in lowering the activation barrier of the transition state. In the elimination step, the SPRIX ligand was found to behave as a monodentate ligand due to the hemilability of one of the isoxazoline units thereby facilitating the elimination. Natural population analysis of this pathway showed that the more weakly electron-donating SPRIX ligand, compared with the bis(oxazoline) ligand, BOX, facilitated the formation of the π-olefin complex intermediate, leading to a smaller overall activation energy and a higher reactivity of the Pd-SPRIX catalyst.

A large hydrothermal reservoir beneath Taal Volcano (Philippines) revealed by magnetotelluric observations and its implications to the volcanic activity.

Taal Volcano is one of the most active volcanoes in the Philippines. The magnetotelluric 3D forward analyses indicate the existence of a large high resistivity anomaly (∼100 Ω·m) with a volume of at least 3 km×3 km×3 km, which is capped by a conductive layer (∼10 Ω·m), beneath the Main Crater. This high resistivity anomaly is hypothesized to be a large hydrothermal reservoir, consisting of the aggregate of interconnected cracks in rigid and dense host rocks, which are filled with hydrothermal fluids coming from a magma batch below the reservoir. The hydrothermal fluids are considered partly in gas phase and liquid phase. The presence of such a large hydrothermal reservoir and the stagnant magma below may have influences on the volcano's activity. Two possibilities are presented. First, the 30 January 1911 explosion event was a magmatic hydrothermal eruption rather than a base-surge associated with a phreato-magmatic eruption. Second, the earlier proposed four eruption series may be better interpreted by two cycles, each consisting of series of summit and flank eruptions.

Distinct physiological roles of the three [NiFe]-hydrogenase orthologs in the hyperthermophilic archaeon Thermococcus kodakarensis.

Hydrogenases catalyze the reversible oxidation of molecular hydrogen (H2) and play a key role in the energy metabolism of microorganisms in anaerobic environments. The hyperthermophilic archaeon Thermococcus kodakarensis KOD1, which assimilates organic carbon coupled with the reduction of elemental sulfur (S°) or H2 generation, harbors three gene operons encoding [NiFe]-hydrogenase orthologs, namely, Hyh, Mbh, and Mbx. In order to elucidate their functions in vivo, a gene disruption mutant for each [NiFe]-hydrogenase ortholog was constructed. The Hyh-deficient mutant (PHY1) grew well under both H2S- and H2-evolving conditions. H2S generation in PHY1 was equivalent to that of the host strain, and H2 generation was higher in PHY1, suggesting that Hyh functions in the direction of H2 uptake in T. kodakarensis under these conditions. Analyses of culture metabolites suggested that significant amounts of NADPH produced by Hyh are used for alanine production through glutamate dehydrogenase and alanine aminotransferase. On the other hand, the Mbh-deficient mutant (MHD1) showed no growth under H2-evolving conditions. This fact, as well as the impaired H2 generation activity in MHD1, indicated that Mbh is mainly responsible for H2 evolution. The copresence of Hyh and Mbh raised the possibility of intraspecies H2 transfer (i.e., H2 evolved by Mbh is reoxidized by Hyh) in this archaeon. In contrast, the Mbx-deficient mutant (MXD1) showed a decreased growth rate only under H2S-evolving conditions and exhibited a lower H2S generation activity, indicating the involvement of Mbx in the S° reduction process. This study provides important genetic evidence for understanding the physiological roles of hydrogenase orthologs in the Thermococcales.

Transcriptome Analysis Reveals Key Genes Involved in Weevil Resistance in the Hexaploid Sweetpotato.

Because weevils are the most damaging pests of sweetpotato, the development of cultivars resistant to weevil species is considered the most important aspect in sweetpotato breeding. However, the genes and the underlying molecular mechanisms related to weevil resistance are yet to be elucidated. In this study, we performed an RNA sequencing-based transcriptome analysis using the resistant Kyushu No. 166 (K166) and susceptible Tamayutaka cultivars. The weevil resistance test showed a significant difference between the two cultivars at 30 days after the inoculation, specifically in the weevil growth stage and the suppressed weevil pupation that was only observed in K166. Differential expression and gene ontology analyses revealed that the genes upregulated after inoculation in K166 were related to phosphorylation, metabolic, and cellular processes. Because the weevil resistance was considered to be related to the suppression of larval pupation, we investigated the juvenile hormone (JH)-related genes involved in the inhibition of insect metamorphosis. We found that the expression of some terpenoid-related genes, which are classified as plant-derived JHs, was significantly increased in K166. This is the first study involving a comprehensive gene expression analysis that provides new insights about the genes and mechanisms associated with weevil resistance in sweetpotato.

Real-Time PCR Assay for the Diagnosis and Quantification of Co-infections by Diaporthe batatas and Diaporthe destruens in Sweet Potato.

Foot rot disease caused by Diaporthe destruens (formerly Plenodomus destruens) has become a major concern for the production of sweet potato [Ipomoea batatas (L.) Lam.] in Japan. A related fungus Diaporthe batatas, which causes dry rot disease of sweet potato, is native and is widespread in fields in Japan. The similar characteristics of these two pathogens pose a challenge for conventional disease diagnosis. Currently, there are no effective molecular measures for identifying and distinguishing D. destruens and D. batatas. Here, we demonstrate a real-time PCR assay that distinguishes and quantifies D. batatas and D. destruens from co-infected sweet potato. The assay was performed with various simulated DNA combinations of D. batatas and D. destruens ranging from 1:1 to 1:100000. The assay was also used with the ratios of D. batatas: D. destruens: sweet potato DNA ranging from 1:1:1 to 1:1:100000. These assays produced a specific amplification product for each of the pathogens, and quantified the fungal biomass over the entire range tested without detecting false positives. The assay was validated by using infected sweet potato collected from various fields; it showed sufficient sensitivity and specificity to quantify and distinguish D. batatas and D. destruens from these field samples. Thus, our real-time PCR assay would be a useful tool for diagnosis of D. batatas and D. destruens and is expected to provide the foundation for the design of integrated disease management strategies for foot rot disease in sweet potato.

Treatment effects of renin-angiotensin system inhibitor and calcium channel blocker in patients with coronary artery narrowing (from the Japanese Coronary Artery Disease Study).

Low-dose antihypertensive drugs in combination are prescribed frequently in clinical practice. Combination treatment is superior to monotherapy with higher doses of each drug in terms of blood pressure reduction and side effects. However, it is unclear whether combination treatment provides additional prognostic benefit beyond the blood pressure lowering effects. We assessed the usefulness of the combined treatment of a renin-angiotensin system inhibitor (RASI) and a calcium channel blocker (CCB) for all cardiovascular events in the Japanese Coronary Artery Disease (JCAD) Study population. In the JCAD Study, which is an observational and non-randomized trial, 13,812 patients with angiographically shown narrowing >50% in ≥1 of 3 major coronary arteries were followed up for a mean of 2.7 years. The primary endpoint of the study was all cardiovascular events. In the present study, baseline covariates possibly influencing the event rate were adjusted between the different treatment groups. There was no statistically significant difference in the event rate between the RASI monotherapy and combined treatment groups, although Kaplan-Meier analysis showed a 23% (p = 0.0003) relative risk reduction with an RASI monotherapy compared with the control group. In conclusion, there may be no additional benefit beyond blood pressure lowering effects in the combination of an RASI and a CCB in patients with angiographically documented CAD.

Diagnosis of primary versus metastatic ovarian adenocarcinoma using p53 gene mutation analysis.

Distinguishing primary ovarian cancer from metastatic colorectal cancer is often difficult by a conventional pathological examination alone. We assessed the usefulness of p53 gene mutation analysis for the differential diagnosis of ovarian adenocarcinoma. A 66-year-old woman suffered multiple organ metastases, including the liver, para-aortic lymph node, and right ovary, following an operation for advanced sigmoid colon cancer. She underwent ovarian resection after effective chemotherapy against the liver and para-aortic lymph node cancer. Histological analysis suggested primary ovarian cancer. Therefore, we applied p53 gene mutation analysis for the differential diagnosis of primary versus metastatic ovarian cancer from sigmoid colon cancer. The direct sequence of the p53 gene demonstrated the same gene mutation in codon 211 (ACT to ATT) in both the sigmoid colon and ovarian cancers. According to the International Agency for Research on Cancer TP53 mutation database, this type of p53 mutation in colorectal cancer and ovarian cancer is 0.13% (5/3,693) and 0% (0/1,494), respectively. Therefore, we determined that the ovarian tumor was metastatic. Although p53 gene mutation analysis has been applied in some cases, this modality is very useful for the differential diagnosis of primary and metastatic cancer.

Prognostic effects of combined treatment with calcium channel blockers and statins in patients with coronary narrowing: from the Japanese Coronary Artery Disease study.

Calcium channel blockers (CCB) and statins are frequently prescribed for patients with coronary artery disease (CAD) complicated by hypertension and/or hypercholesterolemia. CCB have pleiotropic actions beyond their blood pressure-lowering effect, while statins have pleiotropic actions beyond their cholesterol-lowering effect. We assessed the hypothesis that combined treatment with CCB and statins has additional prognostic benefits resulting from potential additive or synergistic pleiotropic actions of both classes of drugs in the Japanese CAD (JCAD) study population. The JCAD study consisted of 13,812 patients with angiographically demonstrable significant coronary narrowing in at least 1 of 3 major coronary arteries who were followed-up for a mean of 2.7 years (follow-up rate, 88.4%). The primary endpoint of the present study was all cardiovascular events. We compared the event rate between patients receiving neither CCB nor statins and those receiving each drug alone or as a combination treatment using propensity score matching analysis. The rate of all events was 62.8 per 1,000 patient-years in the JCAD study. Kaplan-Meier analysis with the log-rank test showed no statistically significant difference in the event rate in each comparison. In conclusion, there may be no additional prognostic benefit beyond the blood-pressure-lowering and cholesterol-lowering effects in the combined treatment with CCB and statins for angiographically documented CAD patients.

Development of molecular markers associated with resistance to Meloidogyne incognita by performing quantitative trait locus analysis and genome-wide association study in sweetpotato.

The southern root-knot nematode, Meloidogyne incognita, is a pest that decreases yield and the quality of sweetpotato [Ipomoea batatas (L.) Lam.]. There is a demand to produce resistant cultivars and develop DNA markers to select this trait. However, sweetpotato is hexaploid, highly heterozygous, and has an enormous genome (∼3 Gb), which makes genetic linkage analysis difficult. In this study, a high-density linkage map was constructed based on retrotransposon insertion polymorphism, simple sequence repeat, and single nucleotide polymorphism markers. The markers were developed using F1 progeny between J-Red, which exhibits resistance to multiple races of M. incognita, and Choshu, which is susceptible to multiple races of such pest. Quantitative trait locus (QTL) analysis and a genome-wide association study detected highly effective QTLs for resistance against three races, namely, SP1, SP4, and SP6-1, in the Ib01-6 J-Red linkage group. A polymerase chain reaction marker that can identify genotypes based on single nucleotide polymorphisms located in this QTL region can discriminate resistance from susceptibility in the F1 progeny at a rate of 70%. Thus, this marker could be helpful in selecting sweetpotato cultivars that are resistant to multiple races of M. incognita.

The influence of barley malt protein modification on beer foam stability and their relationship to the barley dimeric alpha-amylase inhibitor-I (BDAI-I) as a possible foam-promoting protein.

The foam stability of beer is one of the important key factors in evaluating the quality of beer. The purpose of this study was to investigate the relationship between the level of malt modification (degradation of protein, starch, and so on) and the beer foam stability. This was achieved by examining foam-promoting proteins using two-dimensional gel electrophoresis (2DE). We found that the foam stability of beer samples brewed from the barley malts of cultivars B and C decreased as the level of malt modification increased; however, the foam stability of cultivar A did not change. To identify the property providing the increased foam stability of cultivar A, we analyzed beer proteins using 2DE. We analyzed three fractions that could contain beer foam-promoting proteins, namely, beer whole proteins, salt-precipitated proteins, and the proteins concentrated from beer foam. As a result, we found that in cultivar A, some protein spots did not change in any of these three protein fractions even when the level of malt modification increased, although the corresponding protein spots in cultivars B and C decreased. We analyzed these protein spots by peptide mass finger printing using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. As a result, all of these spots were identified as barley dimeric alpha-amylase inhibitor-I (BDAI-I). These results suggest that BDAI-I is an important contributor to beer foam stability.

[The efficacy of surgical resection and chemo-endocrine therapy for patients with local recurrence or axillary lymph node metastasis of breast cancer].

We evaluated a surgical resection and chemo-endocrine therapy and prognosis for patients with local recurrence or axillary lymph node metastasis of breast cancer. Twenty-one patients with local recurrence or axillary lymph node metastasis without a distant metastasis were enrolled in this study. Thirteen of the 21 patients underwent a surgical resection. Resection of recurrent lesion in residual breast after breast conserving therapy for six of the 13 patients, axillary lymph node dissection (ALND) for four, and resection of thoracic wall lesion for three were performed. Five of the patients who underwent resection of residual breast lesion, four of the patients who underwent ALND and two of the patients who underwent resection of thoracic wall lesion have survived. One of the patients who underwent resection of residual breast lesion and one of the patients who underwent resection of thoracic wall lesion were dead. In eight non-operable patients, five were dead and three have survived. Median recurrence free interval was 24 months in operable patients and 27 months in non-operable patients. Median survival time after recurrence was 29 months in operable patients and 12 months in non-operable patients. The surgical with chemo-endocrine therapy promises to control well to local recurrence or axillary lymph node metastasis for the patients we selected.

Comparison of cardiovascular events in patients with angiographically documented coronary narrowing with combined renin-angiotensin system inhibitor plus statin versus renin-angiotensin system inhibitor alone versus statin alone (from the Japanese Coronary Artery Disease Study).

Statins and renin-angiotensin system (RAS) inhibitors are 2 classes of drugs prescribed frequently in clinical practice that may have pleiotropic effects in addition to cholesterol-lowering and blood pressure-lowering effects, respectively. Combined treatment with statins and RAS inhibitors may have additional benefits beyond each monotherapy. We assessed the usefulness of the combined treatment in the Japanese Coronary Artery Disease (JCAD) Study population. In the JCAD Study, 13,812 patients with angiographically shown narrowing in > or =1 of 3 major coronary arteries were followed up for a mean of 2.7 years. The primary end point of the study was all cardiovascular events. In the present study, baseline covariates possibly influencing the event rate were adjusted between the control and treatment groups. Although there were no statistically significant differences in event rates between patients receiving neither statins nor RAS inhibitors and those receiving either drug, Kaplan-Meier analysis showed a 22% decrease (p = 0.0286) in the event rate with combined treatment. In conclusion, statins combined with RAS inhibitors may decrease cardiovascular events in patients with coronary artery disease.

[Two patients having recurrent breast cancer with brain metastases well controlled with a gamma knife radio-surgery].

We report two patients having recurrent breast cancer with brain metastases that was controlled well with a gamma knife radio-surgery. The patient is a 50-year-old woman. She underwent radical mastectomy for right breast cancer in September 1993. She suffered from multiple liver metastases in June 2000, so CEF therapy contained hepatic arterial infusion chemotherapy, and extended right lobectomy of the liver were performed in December 2001. Afterward, pleurodesis was carried out to the carcinomatous pleurisy. Then she underwent simple total hysterectomy and bilateral oophorectomy for torsion of the metastatic ovarian tumor. MRI study revealed brain metastases with a diameter of 1 cm in her right midbrain in April 2005, so a gamma knife radio-surgery was performed. After the radio-surgery, a weekly paclitaxel therapy followed by peroral chemotherapy with capecitabine was started, and she took the regimen continuously. Another patient is a 56-year-old woman. She underwent skin sparing mastectomy with axillary lymph node dissection for right breast cancer in November 2002. Metastases to the base of her skull were found in October 2004, so a gamma knife radio-surgery was carried out. After the radio-surgery, a weekly paclitaxel therapy with anastrozole was started. In both of the two patients, the metastatic brain tumors have not shown growth so far and are under good control as of March 2006.

[A case of femoral artery pseudoaneurysm occurring in the site of a reservoir port for hepatic arterial infusion].

A 73-year-old man underwent partial hepatic resection (55) for metachronous metastatic liver tumor from cecal cancer in November 2005. A reservoir port for hepatic arterial infusion (HAI) adjuvant chemotherapy was placed in the right femoral artery and the HAI chemotherapy was carried out. In January 2006, he had swellings of the right lower leg and inguinal region and was admitted to our hospital for a hematoma in the site of the reservoir port and deep venous thrombosis. The swelling of the right lower leg went down with a bed rest in a couple of days. However, the hematoma of the reservoir port site was increased. The hematoma was removed and sutured to stop bleeding and then compression homeostasis was applied for a week. An enhanced pelvic CT scan showed a pseudoaneurysm in the femoral artery and an impending rupture was suspected. He was immediately referred to a vascular surgeon and underwent emergency surgery. Intraoperative angiography showed a pseudoaneurysm, 2.5 cm in diameter, in the femoral artery. An approximate 1 cm tear around the catheter insertion site was found and a primary suture was performed. A rapid diagnosis and treatment are required when a pseudoaneurysm is suspected during HAI chemotherapy.