A deletion in FLS2 and its expansion after domestication caused global dissemination of melon cultivars defective in flagellin recognition.

FLAGELLIN SENSING 2 (FLS2) encodes a pattern recognition receptor that perceives bacterial flagellin. While putative FLS2 orthologs are broadly conserved in plants, their functional characterization remains limited. Here, we report the identification of orthologs in cucumber (Cucumis sativus) and melon (C. melo), named CsFLS2 and CmFLS2, respectively. Homology searching identified CsFLS2, and virus-induced gene silencing (VIGS) demonstrated that CsFLS2 is required for flg22-triggered ROS generation. Interestingly, genome re-sequencing of melon cv. Lennon and subsequent genomic PCR revealed that Lennon has two CmFLS2 haplotypes, haplotype I encoding full-length CmFLS2 and haplotype II encoding a truncated form. We show that VIGS-mediated knockdown of CmFLS2 haplotype I resulted in a significant reduction in both flg22-triggered ROS generation and immunity to a bacterial pathogen in melon cv. Lennon. Remarkably, genomic PCR of CmFLS2 revealed that 68% of tested commercial melon cultivars possess only CmFLS2 haplotype II: these cultivars thus lack functional CmFLS2. To explore evolutionary aspects of CmFLS2 haplotype II occurrence, we genotyped the CmFLS2 locus in 142 melon accessions by genomic PCR and analyzed 437 released sequences. The results suggest that CmFLS2 haplotype II is derived from C. melo subsp. melo. Furthermore, we suggest that the proportion of CmFLS2 haplotype II increased among the improved melo group compared with the primitive melo group. Collectively, these findings suggest that the deleted FLS2 locus generated in the primitive melo subspecies expanded after domestication, resulting in the spread of commercial melon cultivars defective in flagellin recognition, which is critical for bacterial immunity.

Genetic characterization of cucumber genetic resources in the NARO Genebank indicates their multiple dispersal trajectories to the East.

KEY MESSAGE: Genotyping-by-sequencing of 723 worldwide cucumber genetic resources revealed that cucumbers were dispersed eastward via at least three distinct routes, one to Southeast Asia and two from different directions to East Asia. The cucumber (Cucumis sativus) is an economically important vegetable crop cultivated and consumed worldwide. Despite its popularity, the manner in which cucumbers were dispersed from their origin in South Asia to the rest of the world, particularly to the east, remains a mystery due to the lack of written records. In this study, we performed genotyping-by-sequencing (GBS) on 723 worldwide cucumber accessions, mainly deposited in the Japanese National Agriculture and Food Research Organization (NARO) Genebank, to characterize their genetic diversity, relationships, and population structure. Analyses based on over 60,000 genome-wide single-nucleotide polymorphisms identified by GBS revealed clear genetic differentiation between Southeast and East Asian populations, suggesting that they reached their respective region independently, not progressively. A deeper investigation of the East Asian population identified two subpopulations with different fruit characteristics, supporting the traditional classification of East Asian cucumbers into two types thought to have been introduced by independent routes. Finally, we developed a core collection of 100 accessions representing at least 93.2% of the genetic diversity present in the entire collection. The genetic relationships and population structure, their associations with geographic distribution and phenotypic traits, and the core collection presented in this study are valuable resources for elucidating the dispersal history and promoting the efficient use and management of genetic resources for research and breeding in cucumber.

Neurological recovery rate and predictive factors of incomplete AIS grade C spinal cord injury in the older aged population.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To define the prognosis and predictive factors for neurological improvement in older patients with incomplete spinal cord injury (SCI) of American Spinal Injury Association Impairment Scale grade C (AIS-C). SETTINGS: Multi-institutions in Japan. METHODS: We included patients aged ≥65 years with traumatic SCI of AIS-C who were treated conservatively or surgically with >3 follow-up months. To identify factors related to neurological improvement, patients were divided into three groups according to their neurological status at the final follow-up, with univariate among-group comparisons of demographics, radiographic, and therapeutic factors. Significant variables were included in the multivariate logistic regression analysis. RESULTS: Overall, 296 older patients with SCI of AIS-C on admission were identified (average age: 75.2 years, average follow-up: 18.7 months). Among them, 190 (64.2%) patients improved to AIS-D and 21 (7.1%) patients improved to AIS-E at final follow-up. There were significant among-group differences in age (p = 0.026), body mass index (p = 0.007), status of pre-traumatic activities of daily living (ADL) (p = 0.037), and serum albumin concentrations (p = 0.011). Logistic regression analysis showed no significant differences in variables in the stratified group of patients who improved to AIS-D. Meanwhile, serum albumin was a significant variable in patients who improved to AIS-E (p = 0.026; OR: 6.20, pre-traumatic ADL was omitted due to data skewness). CONCLUSIONS: Most older patients with incomplete AIS-C SCI demonstrated at least 1 grade of neurological improvement. However, <10% of patients achieved complete recovery. Key predictors of complete recovery were high serum albumin levels on admission and independent pre-traumatic ADL. SPONSORSHIP: No funding was received for this study.

[A Case of a Gastrointestinal Stromal Tumor of the Stomach with Lymph Node Metastasis].

A 87-year-old female was pointed out wall thickness in the upper part of gastric body for examination of anemia. The mass had a contrast effect, some of it protruded outside the wall, and the surrounding lymph nodes were enlarged. Upper endoscopy showed irregular ulcerative lesion with submucosal volume from posterior wall to the greater curvature in the upper part of gastric body. Biopsy was performed, and GIST of stomach was diagnosed. Surgery was performed for the GIST of the stomach. During open surgery, invasion of pancreatic tail was observed, therefore proximal gastrectomy with D1 lymph node dissection and distal pancreatectomy were performed. Pathologically, the tumor measured 95×78×65 mm with mitotic figures(38/50 high-power fields). Immunohistochemical analysis revealed that tumor cells expressed positive results for c-kit, α-SMA and CD34, and negative results for S-100 and desmin on the basis of the histology and immunostaining profile, the tumor was diagnosed as a GIST. The patient was classed as high risk according to Fletcher's risk classification. Tumor invades pancreatic tail, and lymph node metastasis was observed. She was discharged on the postoperative day 27 and alive without tumor recurrence at 6 months after surgery, not undergoing adjuvant chemotherapy.

[A Case of Resection of Leiomyosarcoma Suspected to Originate from the Right Ovarian Vein].

We present a 58-year-old female patient who underwent resection of a leiomyosarcoma arising from the right ovarian vein. She was referred to our hospital because of lower abdominal pain that had been present for 1 month prior to the visit. Ultrasound examination revealed a well-defined, smooth, lobulated, highly vascular mass(57 mm)adjacent to the distal portion of the duodenum. Contrast-enhanced computed tomography revealed the contrast enhancement mass (60 mm)located surround the right ovarian vein. In abdominal magnetic resonance image examination, the mass exhibited isointense signal on T1-weighted images, high signal on T2-weighted images, and restricted diffusion on diffusion- weighted images. We suspected primary leiomyosarcoma of the ovarian vein and proceeded with surgical intervention. On intraoperative findings, the mass was in contact with the duodenum and the inferior vena cava but dissection was easily achieved. We excised the mass together with the right ovarian vein. Pathological findings showed the mass was composed of proliferating spindle-shaped cells arranged in bundles. Some areas showed polygonal nuclear atypia and abnormal mitotic figures. Additional immunostaining showed positive for α-SMA, caldesmon, calponin, and negative for desmin, CD34, CKA1/AE3, S100. Based on the intraoperative findings, we diagnosed it as leiomyosarcoma arising of the right ovarian vein.

Safe, One-Pot, Homogeneous Direct Synthesis of H2O2.

Hydrogen peroxide is an environmentally friendly oxidizing agent but current synthetic methods are wasteful. This is a result of the high flammability of H2/O2 mixtures and/or the requirement for cocatalysts. In this paper, we report the synthesis of H2O2 by means of a homogeneous catalyst, which allows a safe, one-pot synthesis in water, using only H2 and O2. This catalyst is capable of removing electrons from H2, storing them for the reduction of O2, and then permitting the protonation of the reduced oxygen to H2O2. The turnover number (TON) is 910 under an H2/O2 (95/5) atmosphere (1.9 MPa) for 12 h at 23 °C, which is the highest of any homogeneous catalyst. Furthermore, we propose a reaction mechanism based on two crystal structures.

Prognostic impact of respiratory dysfunction in elderly patients with cervical spinal cord injury and/or fractures: a multicenter survey.

PURPOSE: To investigate the impact of early post-injury respiratory dysfunction for neurological and ambulatory ability recovery in patients with cervical spinal cord injury (SCI) and/or fractures. METHODS: We included 1,353 elderly patients with SCI and/or fractures from 78 institutions in Japan. Patients who required early tracheostomy and ventilator management and those who developed respiratory complications were included in the respiratory dysfunction group, which was further classified into mild and severe respiratory groups based on respiratory weaning management. Patient characteristics, laboratory data, neurological impairment scale scores, complications at injury, and surgical treatment were evaluated. We performed a propensity score-matched analysis to compare neurological outcomes and mobility between groups. RESULTS: Overall, 104 patients (7.8%) had impaired respiratory function. In propensity score-matched analysis, the respiratory dysfunction group had a lower home discharge and ambulation rates (p = 0.018, p = 0.001, respectively), and higher rate of severe paralysis (p < 0.001) at discharge. At the final follow-up, the respiratory dysfunction group had a lower ambulation rate (p = 0.004) and higher rate of severe paralysis (p < 0.001). Twenty-six patients with severe disability required respiratory management for up to 6 months post-injury and died of respiratory complications. The mild and severe respiratory dysfunction groups had a high percentage of severe paraplegic cases with low ambulatory ability; there was no significant difference between them. The severe respiratory dysfunction group tended to have a poorer prognosis. CONCLUSION: Respiratory dysfunction in elderly patients with SCI and/or cervical fracture in the early post-injury period reflects the severity of the condition and may be a useful prognostic predictor.

Melon diversity on the Silk Road by molecular phylogenetic analysis in Kazakhstan melons.

To uncover population structure, phylogenetic relationship, and diversity in melons along the famous Silk Road, a seed size measurement and a phylogenetic analysis using five chloroplast genome markers, 17 RAPD markers and 11 SSR markers were conducted for 87 Kazakh melon accessions with reference accessions. Kazakh melon accessions had large seed with exception of two accessions of weedy melon, Group Agrestis, and consisted of three cytoplasm types, of which Ib-1/-2 and Ib-3 were dominant in Kazakhstan and nearby areas such as northwestern China, Central Asia and Russia. Molecular phylogeny showed that two unique genetic groups, STIa-2 with Ib-1/-2 cytoplasm and STIa-1 with Ib-3 cytoplasm, and one admixed group, STIAD combined with STIa and STIb, were prevalent across all Kazakh melon groups. STIAD melons that phylogenetically overlapped with STIa-1 and STIa-2 melons were frequent in the eastern Silk Road region, including Kazakhstan. Evidently, a small population contributed to melon development and variation in the eastern Silk Road. Conscious preservation of fruit traits specific to Kazakh melon groups is thought to play a role in the conservation of Kazakh melon genetic variation during melon production, where hybrid progenies were generated through open pollination.

Elucidation of genetic variation and population structure of melon genetic resources in the NARO Genebank, and construction of the World Melon Core Collection.

Numerous genetic resources of major crops have been introduced from around the world and deposited in Japanese National Agriculture and Food Research Organization (NARO) Genebank. Understanding their genetic variation and selecting a representative subset ("core collection") are essential for optimal management and efficient use of genetic resources. In this study, we conducted genotyping-by-sequencing (GBS) to characterize the genetic relationships and population structure in 755 accessions of melon genetic resources. The GBS identified 39,324 single-nucleotide polymorphisms (SNPs) that are distributed throughout the melon genome with high density (one SNP/10.6 kb). The phylogenetic relationships and population structure inferred using this SNP dataset are highly associated with the cytoplasm type and geographical origin. Our results strongly support the recent hypothesis that cultivated melon was established in Africa and India through multiple independent domestication events. Finally, we constructed a World Melon Core Collection that covers at least 82% of the genetic diversity and has a wide range of geographical origins and fruit morphology. The genome-wide SNP dataset, phylogenetic relationships, population structure, and the core collection provided in this study should largely contribute to genetic research, breeding, and genetic resource preservation in melon.

A rise-assisting robot extends life space and improves facial expressions of nursing home residents.

BACKGROUND: The introduction of nursing care-support devices using robotic technology is expected to reduce the task burden in long-term care facilities. OBJECTIVE: To investigate the use of the rise-assisting robot, Resyone, in extending and improving the life space of nursing home residents with severe care needs. METHODS: We performed a feasibility study in which Resyone was used to facilitate visits to additional sites in and around the nursing home as part of the care package of three residents. Two weeks before and four weeks after implementation of the new arrangements, the 30 caregivers involved were asked to record transfer times and destinations, while also checking the residents' facial expressions. RESULTS: Before implementation, participants had limited life spaces, but afterwards they regularly visited additional destinations including the garden, home entrance and corridors, which previously they had not visited frequently. The residents' facial expressions became more positive and less negative. This study demonstrates that Resyone can enrich care activities in severely disabled individuals. CONCLUSION: These findings suggest that the sustainable use of Resyone would improve the quality of care at care facilities. Moreover, the extension of otherwise limited life space has the potential to improve care receivers' quality of life. TRIAL REGISTRATION: UMIN Clinical Trials Registry No. UMIN000039204 (20/01/2020); retrospectively registered; interventional study; parallel, non-randomized, single blinded. URL of trial registry records: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000044709 .

Does surgery improve neurological outcomes in older individuals with cervical spinal cord injury without bone injury? A multicenter study.

STUDY DESIGN: Retrospective multicenter study. OBJECTIVES: To investigate the neurological outcomes of older individuals treated with surgery versus conservative treatment for cervical spinal cord injury (CSCI) without bone injury. SETTING: Thirty-three medical institutions in Japan. METHODS: This study included 317 consecutive persons aged ≥65 years with CSCI without bone injury in participating institutes between 2010 and 2020. The participants were followed up for at least 6 months after the injury. Individuals were divided into surgery (n = 114) and conservative treatment (n = 203) groups. To compare neurological outcomes and complications between the groups, propensity score matching of the baseline factors (characteristics, comorbidities, and neurological function) was performed. RESULTS: After propensity score matching, the surgery and conservative treatment groups comprised 89 individuals each. Surgery was performed at a median of 9.0 (3-17) days after CSCI. Baseline factors were comparable between groups, and the standardized difference in the covariates in the matched cohort was <10%. The American Spinal Injury Association (ASIA) impairment scale grade and ASIA motor score (AMS) 6 months after injury and changes in the AMS from baseline to 6 months after injury were not significantly different between groups (P = 0.63, P = 0.24, and P = 0.75, respectively). Few participants who underwent surgery demonstrated perioperative complications such as dural tear (1.1%), surgical site infection (2.2%), and C5 palsy (5.6%). CONCLUSION: Conservative treatment is suggested to be a more favorable option for older individuals with CSCI without bone injuries, but this finding requires further validation.

A multicenter study of 1-year mortality and walking capacity after spinal fusion surgery for cervical fracture in elderly patients.

BACKGROUND: The 1-year mortality and functional prognoses of patients who received surgery for cervical trauma in the elderly remains unclear. The aim of this study is to investigate the rates of, and factors associated with mortality and the deterioration in walking capacity occurring 1 year after spinal fusion surgery for cervical fractures in patients 65 years of age or older. METHODS: Three hundred thirteen patients aged 65 years or more with a traumatic cervical fracture who received spinal fusion surgery were enrolled. The patients were divided into a survival group and a mortality group, or a maintained walking capacity group and a deteriorated walking capacity group. We compared patients' backgrounds, trauma, and surgical parameters between the two groups. To identify factors associated with mortality or a deteriorated walking capacity 1 year postoperatively, a multivariate logistic regression analysis was conducted. RESULTS: One year postoperatively, the rate of mortality was 8%. A higher Charlson comorbidity index (CCI) score, a more severe the American Spinal Cord Injury Association impairment scale (AIS), and longer surgical time were identified as independent factors associated with an increase in 1-year mortality. The rate of deterioration in walking capacity between pre-trauma and 1 year postoperatively was 33%. A more severe AIS, lower albumin (Alb) and hemoglobin (Hb) values, and a larger number of fused segments were identified as independent factors associated with the increased risk of deteriorated walking capacity 1 year postoperatively. CONCLUSIONS: The 1-year rate of mortality after spinal fusion surgery for cervical fracture in patients 65 years of age or older was 8%, and its associated factors were a higher CCI score, a more severe AIS, and a longer surgical time. The rate of deterioration in walking capacity was 33%, and its associated factors were a more severe AIS, lower Alb, lower Hb values, and a larger number of fused segments.

[A Case of Intussusception Caused by Ascending Colon Cancer That Underwent Elective Surgery without Repositioning].

An 81-year-old man visited his previous doctor with complaints of fever, vomiting, and diarrhea, and was transferred to our hospital on the 8th day after being admitted to the hospital for further treatment for a mass in the right side of his abdomen on CT. At the time of transfer, a fist-sized mass was palpable in the right side of the abdomen, but there was no tenderness, and blood tests showed that the white blood cell count was 10,700/µL and CRP 1.36 mg/dL, indicating a mild increase in inflammatory reaction. Contrast-enhanced CT showed an 8-cm diameter mass in the ascending colon with a stratified structure, and an antegrade intussusception with the mass as the advanced part. No intestinal obstruction was showed, and the contrast effect on the wall of the intestinal wall of the intussusception was favorable. Since the intussusception was already present on the previous CT scan, and since the patient also had severe aortic stenosis and a cardiothoracic examination was necessary, we decided on an elective operation. During the waiting period, lower gastrointestinal endoscopy revealed a type 1 tumor in the ascending colon, and biopsy revealed a highly differentiated tubular adenocarcinoma. The scope was not passed through to the oral side, and endoscopic repositioning was difficult. On the 19th day(12th day of admission), right hemicolectomy of the colon with D3 lymphadenectomy was performed. Since the descending duodenal wall was partially retracted into the area of the duplication, a partial resection of the duodenal wall was also performed, and the specimen was removed without releasing the duplication. Histopathologically, the tumor was diagnosed a 9.5×5.7 cm type 1 tumor with pT3, pN0, cM0, pStage Ⅱa(9th edition). The patient was discharged on the 9th postoperative day with good postoperative course.

[A Case of Ascending Colon Cancer with a Tumor Thrombus in the Superior Mesenteric Vein].

The progression of intravenous tumor thrombus in colorectal cancer is rare and reports on its resection are limited. This study reports a case of ascending colon cancer with a tumor thrombus in the superior mesenteric vein(SMV). A 44-year-old woman was admitted to our hospital for right, lower abdominal pain. Dynamic CT revealed an enhanced mass in the ascending colon and a tumor thrombus in the SMV. She was diagnosed with ascending colon cancer and an SMV tumor thrombus. An extended right hemicolectomy was performed. The SMV tumor thrombus extended from the gastrocolic trunk (GCT)to the right gastroepiploic vein and the anterior superior pancreaticoduodenal vein. To remove the tumor thrombus, a wedge-shaped incision was made through the SMV. Pathological examination showed a moderately differentiated adenocarcinoma of the ascending colon with extra-regional lymph node metastasis(No. 6)and intrapancreatic venous invasion. The pathological staging was pT4b, pN0, pM1a, pStage Ⅳa(Japanese Classification 9th edition). The patient was discharged on day 13 postoperatively. After discharge, 14 courses of mFOLFOX6 plus bevacizumab chemotherapy were administered. The patient is currently alive with no recurrence 15 months postoperatively.

Oncologic Reappraisal of Bile Duct Resection for Middle-Third Cholangiocarcinoma.

BACKGROUND: Although bile duct resection (BDR) in addition to pancreaticoduodenectomy (PD) is considered a surgical approach in patients with middle-third cholangiocarcinoma (MCC), available prognostic information after BDR remains very limited. The aim of this study was to reappraise BDR from the viewpoint of surgical oncology. METHODS: Patients who underwent BDR or PD for MCC between 2001 and 2010 at 32 Japanese hospitals were included. Clinicopathological factors were retrospectively compared according to surgical procedure to identify a subset cohort who benefited most from BDR. RESULTS: During the study, 92 patients underwent BDR (n = 38) or PD (n = 54). BDR was characterized by a shorter operation time, less blood loss, less frequent complications, and lower mortality, than PD. The incidence of positive surgical margins was 26.3% versus 5.6% (P = 0.007). The survival rate after BDR was significantly worse than that after PD: 38.8% versus 54.8% at 5 years (P = 0.035), and BDR was independently associated with deteriorated survival [hazard ratio (HR), 1.76; P = 0.023] by multivariable analysis. In the BDR group, tumor length < 15 mm (HR, 3.38; P = 0.017) and ductal margin length ≥ 10 mm (HR, 2.54; P = 0.018) were independent positive prognostic factors. Stratified by these two favorable factors, the 5-year survival rate was 63.0% in patients with 1/2 factors and 6.7% in those with 0 factors (P < 0.001). CONCLUSION: In patients with MCC, BDR provided a better short-term and a worse long-term outcome than PD. However, patient selection using tumor length and ductal margin length may allow a favorable survival probability even after BDR.

Origin and Dynamics of Rwt6, a Wheat Gene for Resistance to Nonadapted Pathotypes of Pyricularia oryzae.

Avirulence of Eleusine isolates of Pyricularia oryzae on common wheat is conditioned by at least five avirulence genes. One is PWT3 corresponding to resistance gene Rwt3 located on chromosome 1D. We identified a resistance gene corresponding to a second avirulence gene, PWT6, and named it Rmg9 (Rwt6). Rwt6 was closely linked to Rwt3. A survey of the population of Aegilops tauschii, the D genome donor to common wheat, revealed that some accessions from the southern coastal region of the Caspian Sea, the birthplace of common wheat, carried both genes. Rwt6 and Rwt3 carriers accounted for 65 and 80%, respectively, of accessions in a common wheat landrace collection. The most likely explanation of our results is that both resistance genes were simultaneously introduced into common wheat at the time of hybridization of Triticum turgidum and A. tauschii. However, a prominent difference was recognized in their geographical distributions in modern wheat; Rwt3 and Rwt6 co-occurred at high frequencies in regions to the east of the Caspian Sea, whereas Rwt6 occurred at a lower frequency than Rwt3 in regions to the west. This difference was considered to be associated with range of pathotypes to which these genes were effective. A. tauschii accessions carrying Rwt3 and Rwt6 also carried Rwt4, another resistance gene involved in the species specificity. We suggest that the gain of the D genome should have given an adaptive advantage to the genus Triticum by conferring disease resistance.

Identification of care tasks for the use of wearable transfer support robots - an observational study at nursing facilities using robots on a daily basis.

BACKGROUND: To reduce the physical burden of caregivers, wearable transfer support robots are highly desirable. Although these robots are reportedly effective for specific tasks in experimental environments, there is little information about their effectiveness at nursing care facilities. The aim of this study was to identify care tasks and operations suitable for the use of these robots among caregivers in nursing facilities where these robots have been in use on a daily basis. METHODS: A 1-min observational time-motion analysis was conducted to examine care tasks and operations in two nursing facilities where wearable transfer support robots, namely Muscle Suit or HAL® Lumbar Type for Care Support, have been used routinely on a daily basis for more than 24 months. RESULTS: Analysis of the care tasks and their time ratio while wearing the equipment revealed that both robots were used conspicuously for direct care in over 70% of transits, especially during transfer assistance and toileting care. Furthermore, these robots were used intensively in the morning along with wake-up calls to care recipients, where pre-assigned wearers used them as part of their "routine work." CONCLUSIONS: We found that these wearable transfer support robots enabled effective performance of care tasks and operations in nursing facilities where these robots have been used on a daily basis for an extended period of time. These results may lead to the effective implementation and sustained operation of other types of care robots in the future. TRIAL REGISTRATION: UMIN Clinical Trials Registry no. UMIN000039204 . Trial registration date: January 21, 2020. Interventional study. Parallel, non-randomized, single blinded.

Distribution of two groups of melon landraces and inter-group hybridization enhanced genetic diversity in Vietnam.

To understand the genetic diversity and differentiation of Vietnamese melon (Cucumis melo L.), we collected 64 landraces from the central and southern parts of the country and assessed molecular polymorphism using simple sequence repeat and random amplified polymorphic DNA markers. The Vietnamese melon was divided into seven cultivar groups, namely "Dua le", "Dua vang", "Dua bo", "Dua gang-andromonoecious", "Dua gang-monoecious", "Dua thom", "Montok", and the weedy-type melon "Dua dai". Among these, Dua le, Dua vang, Dua bo, and Dua gang-andromonoecious are cultivated on plains and they formed cluster II along with the reference accessions of Conomon and Makuwa. Based on genetic distance, Dua le and Dua vang were regarded as Makuwa and Dua bo and Dua gang-andromonoecious as Conomon. In contrast, Dua thom and Montok are cultivated in highlands, and they formed cluster III along with landraces from the southern and eastern foot of the Himalayas. Dua gang-monoecious which is commonly cultivated in the southern parts of Vietnam, exhibited the greatest genetic diversity, as explained by its possible origin through the hybridization between Dua gang-andromonoecious and Montok. Genetic differences in melon landraces between plains and highlands and hybridization between these two geographical groups have contributed to the enhancement of genetic diversity in Vietnamese melon.

[A Cure Case of Rectal Arteriovenous Malformation with a Large Volume of Melena Caused by Surgery for Rectal Cancer].

This study presents the case of a 52-year-old male suffering from extensive melena. A detailed examination using lower gastrointestinal endoscopy revealed a polyp at the lower rectum; subsequently, endoscopic mucosal resection(EMR)was performed. No other lesion for the melena was observed. Histopathologic findings of the EMR confirmed adenocarcinoma in adenoma, indicating the need for additional surgery. Preoperative contrast-enhanced CT revealed an arteriovenous malformation( AVM)of about 5 cm in the rectal wall at the anal side of the lower rectal cancer. Extensive melena was inferred to be caused by AVM; hence, we performed laparoscopic low anterior resection combined with accessible excision of the AVM and blocked the superior rectal artery, acting as an inflow vessel. Postoperative contrast-enhanced CT confirmed the disappearance of AVM. Thus, we experienced a case in which the block of the inflow vessel, according to the treatment theory of embolism therapy without complete resection of the AVM, enabled the treatment of AVM. Therefore, this case could become a reference for the treatment of lower rectal AVM cases in the future.

Chromosomal Locations of a Non-LTR Retrotransposon, Menolird18, in Cucumis melo and Cucumis sativus, and Its Implication on Genome Evolution of Cucumis Species.

Mobile elements are major regulators of genome evolution through their effects on genome size and chromosome structure in higher organisms. Non-long terminal repeat (non-LTR) retrotransposons, one of the subclasses of transposons, are specifically inserted into repetitive DNA sequences. While studies on the insertion of non-LTR retrotransposons into ribosomal RNA genes and other repetitive DNA sequences have been reported in the animal kingdom, studies in the plant kingdom are limited. Here, using FISH, we confirmed that Menolird18, a member of LINE (long interspersed nuclear element) in non-LTR retrotransposons and found in Cucumis melo, was inserted into ITS and ETS (internal and external transcribed spacers) regions of 18S rDNA in melon and cucumber. Beside the 18S rDNA regions, Menolird18 was also detected in all centromeric regions of melon, while it was located at pericentromeric and sub-telomeric regions in cucumber. The fact that FISH signals of Menolird18 were found in centromeric and rDNA regions of mitotic chromosomes suggests that Menolird18 is a rDNA and centromere-specific non-LTR retrotransposon in melon. Our findings are the first report on a non-LTR retrotransposon that is highly conserved in 2 different plant species, melon and cucumber. The clear distinction of chromosomal localization of Menolird18 in melon and cucumber implies that it might have been involved in the evolutionary processes of the melon (C. melo) and cucumber (C. sativus) genomes.