Socio-economic factors and medical conditions affecting regular stomach cancer screening in Korea: a retrospective longitudinal study using national public health data for 11 years

OBJECTIVE

This study aimed to explore socio-economic factors and medical conditions that affect regular stomach cancer (SC) screening among Korean adults.

STUDY DESIGN

This was a retrospective observational study.

METHODS

Study subjects were 5545 adults aged ≥40 years who participated in the 2007-2012 Korean National Health and Nutrition Examination Survey and were followed up to year 2017 based on data linking to the Korean National Health Insurance Service and Korean Health Insurance Review and Assessment. Socio-economic factors included sex, age, residential area, education, occupation, marital status, disability, public and private health insurance, service through local public health organizations, history of cancer except for SC, and family history of SC. Medical factors included six gastric lesions with the possibility of facilitating SC screening, including benign gastric neoplasm, chronic atrophic gastritis, gastric polyp, Helicobacter pylori infection, intestinal metaplasia, and peptic ulcers. The outcome was adherence to SC screening, which was divided into non-adherence, irregular adherence, and regular adherence.

RESULTS

After adjusting for the effects of socio-economic factors, multivariate ordinal logistic regression revealed that participants with a history of four types of gastric lesions were more likely to regularly participate in SC screening: chronic atrophic gastritis (odds ratio [OR] 1.567; 95% confidence interval [CI] = 1.276-1.923), gastric polyps (OR 1.565; 95% CI = 1.223-2.003), H. pylori infection (OR 1.637; 95% CI = 1.338-2.003), and peptic ulcer (OR 2.226; 95% CI 1.750-2.831).

CONCLUSIONS

To improve participation in SC screening, it is necessary to implement personalized strategies for individuals at risk for gastric cancer in addition to population-based strategies for vulnerable groups.

A multiplex PCR assay for the simultaneous detection of five potexviruses infecting cactus plants using dual-priming oligonucleotides (DPOs) primers

Five potexviruses, namely, cactus virus X (CVX), opuntia virus X, pitaya virus X (PiVX), schlumbergera virus X (SchVX) and zygocactus virus X (ZyVX), have been reported in cactus plants. In this report, a multiplex RT-PCR assay, based on specific dual-priming oligonucleotide (DPO) primers, was developed to detect these five viruses simultaneously in field samples. Using 18 field plants comprising 16 cactus species, these viruses were detected among nine of the 18 plants, including the simultaneous detection of CVX, PiVX, SchVX and ZyVX co-infecting an Aporocactus flagelliformis and a Notocactus leninghausii f. cristatus plant. The multiplex PCR assay was thus applied successfully in the field plants and it would be useful in the diagnosis of viral infections in cactus plants.

ICTV Virus Taxonomy Profile: Alphaflexiviridae

The family Alphaflexiviridae includes viruses with flexuous filamentous virions that are 470–800 nm in length and 12–13 nm in diameter. Alphaflexiviruses have a single-stranded, positive-sense RNA genome of 5.5–9 kb. They infect plants and plant-infecting fungi. They share a distinct lineage of alphavirus-like replication proteins that is unusual in lacking any recognized protease domain. With a single exception, cell-to-cell and long-distance movement is facilitated by triple gene block proteins in plant-infecting genera. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Alphaflexiviridae, which is available at www.ictv.global/report/alphaflexiviridae.

Clinical Experience of 1-Minute Brain MRI Using a Multicontrast EPI Sequence in a Different Scan Environment

BACKGROUND AND PURPOSE

The long scan time of MR imaging is a major drawback limiting its clinical use in neuroimaging; therefore, we aimed to investigate the clinical feasibility of a 1-minute full-brain MR imaging using a multicontrast EPI sequence on a different MR imaging scanner than the ones previously reported.

MATERIALS AND METHODS

We retrospectively reviewed the records of 146 patients who underwent a multicontrast EPI sequence, including T1-FLAIR, T2-FLAIR, T2WI, DWI, and T2*WI sequences. Two attending neuroradiologists assessed the image quality of each sequence to compare the multicontrast EPI sequence with routine MR imaging protocols. We used the Wilcoxon signed rank test and McNemar test to compare the 2 MR imaging protocols.

RESULTS

The multicontrast EPI sequence generally showed sufficient image quality of >2 points using a 4-point assessment scale. Regarding image quality and susceptibility artifacts, there was no significant difference between the multicontrast EPI sequence DWI and routine DWI (P > .05), attesting to noninferiority of the multicontrast EPI, whereas there were significant differences in the other 4 sequences between the 2 MR imaging protocols.

CONCLUSIONS

The multicontrast EPI sequence showed sufficient image quality for clinical use with a shorter scan time; however, it was limited by inferior image quality and frequent susceptibility artifacts compared with routine brain MR imaging. Therefore, the multicontrast EPI sequence cannot completely replace the routine MR imaging protocol at present; however, it may be a feasible option in specific clinical situations such as screening, time-critical diseases or for use with patients prone to motion.

P3453Gender difference in impact of ischemic heart disease on long-term outcome in patients with heart failure reduced ejection fraction

Background

Ischemic heart disease (IHD) is a major underlying etiology in patients with heart failure (HF). Although the impact of IHD on HF is evolving, there is a lack of understanding of how IHD affects long-term clinical outcomes and uncertainty about the role of IHD in determining the risk of clinical outcomes by gender.

Purpose

This study aims to evaluate the gender difference in impact of IHD on long-term clinical outcomes in patients with heart failure reduced ejection fraction (HFrEF).

Methods

Study data were obtained from the nationwide registry which is a prospective multicenter cohort and included patients who were hospitalized for HF composed of 3,200 patients. A total of 1,638 patients with HFrEF were classified into gender (women 704 and men 934). The primary outcome was all-cause death during follow-up and the composite clinical events of all-cause death and HF readmission during follow-up were also obtained. HF readmission was defined as re-hospitalization because of HF exacerbation.

Results

133 women (18.9%) were died and 168 men (18.0%) were died during follow-up (median 489 days; inter-quartile range, 162–947 days). As underlying cause of HF, IHD did not show significant difference between genders. Women with HFrEF combined with IHD had significantly lower cumulative survival rate than women without IHD at long-term follow-up (74.8% vs. 84.9%, Log Rank p=0.001, Figure 1). However, men with HFrEF combined with IHD had no significant difference in survival rate compared with men without IHD (79.3% vs. 83.8%, Log Rank p=0.067). After adjustment for confounding factors, Cox regression analysis showed that IHD had a 1.43-fold increased risk for all-cause mortality independently only in women. (odds ratio 1.43, 95% confidence interval 1.058–1.929, p=0.020). On the contrary to the death-free survival rates, there were significant differences in composite clinical events-free survival rates between patients with HFrEF combined with IHD and HFrEF without IHD in both genders.

Figure 1

Conclusions

IHD as predisposing cause of HF was an important risk factor for long-term mortality in women with HFrEF. Clinician need to aware of gender-based characteristics in patients with HF and should manage and monitor them appropriately and gender-specifically. Women with HF caused by IHD also should be treated more meticulously to avoid a poor prognosis.

Acknowledgement/Funding

None

Detection of Local Recurrence in Patients with Head and Neck Squamous Cell Carcinoma Using Voxel-Based Color Maps of Initial and Final Area under the Curve Values Derived from DCE-MRI

BACKGROUND AND PURPOSE

Early detection of local recurrence is important to increase the chance of cure because local recurrence is the main cause of treatment failure in head and neck squamous cell carcinoma. We evaluated the added value of voxel-based color maps of dynamic contrast-enhanced MR imaging compared with conventional MR imaging alone for detecting local recurrence of head and neck squamous cell carcinoma.

MATERIALS AND METHODS

We retrospectively enrolled 63 consecutive patients with head and neck squamous cell carcinoma after definitive treatment and posttreatment surveillance MR imaging studies that demonstrated focal enhancement at the primary site. Three independent readers assessed conventional MR imaging and a pair of color maps of initial and final 90-second time-signal intensity areas under the curve from dynamic contrast-enhanced MR imaging. The sensitivities, specificities, and accuracies of both conventional MR imaging alone and combined interpretation of conventional and dynamic contrast-enhanced MR imaging were assessed using the clinicopathologic diagnosis as the criterion standard. κ statistics were used to evaluate interreader agreement.

RESULTS

There were 28 patients with subsequently documented local recurrence and 35 with posttreatment change. Adding dynamic contrast-enhanced MR imaging to conventional MR imaging significantly increased the diagnostic accuracies for detecting local recurrence (48%-54% versus 87%-91%; P < .05), with excellent interreader agreement (κ = 0.8; 95% CI, 0.67-0.92 to κ = 0.81; 95% CI, 0.69-0.93). By all 3 readers, the specificities were also significantly improved by adding dynamic contrast-enhanced MR imaging to conventional MR imaging (22%-43% versus 87%-91%; P < .001) without sacrificing the sensitivities (68%-82% versus 86%-89%; P > .05).

CONCLUSIONS

Adding voxel-based color maps of initial and final 90-second time-signal intensity areas under the curve from dynamic contrast-enhanced MR imaging to conventional MR imaging increases the diagnostic accuracy to detect local recurrence in head and neck squamous cell carcinoma by improving the specificity without sacrificing the sensitivity.

Clinical Feasibility of Zero TE Skull MRI in Patients with Head Trauma in Comparison with CT: A Single-Center Study

BACKGROUND AND PURPOSE

Conventional MR imaging techniques cannot produce optimal images of bone structures because bone has little water and a very short T2 life span. The aim of this study was to investigate the clinical feasibility of skull MR imaging using the zero TE sequence in patients with head trauma by assessing its diagnostic image quality and quantitative measurement compared with CT images.

MATERIALS AND METHODS

Thirteen enrolled patients with head trauma were assessed using brain CT and skull MR imaging. Image quality was graded on a 5-point Likert scale to compare the 2 modalities. To evaluate quantitative analyses between the 2 imaging modalities, we measured skull thickness and normalized bone tissue signal. Interobserver reliability was assessed using weighted κ statistics and the intraclass correlation coefficient.

RESULTS

Both imaging techniques clearly depicted skull fractures in all 13 patients. The mean scores for skull MR imaging and CT were 4.65 ± 0.56 and 4.73 ± 0.45 (P = .157), respectively, with substantial interobserver agreement (P < .05). The 2 imaging modalities showed no difference in skull thickness (P = .092) and had good correlation (r ² = 0.997). The mean value of normalized bone tissue signal among the 3 layers of the skull was relatively consistent (P = .401) with high interobserver agreement (P < .001).

CONCLUSIONS

Zero TE skull MR imaging has diagnostic image quality comparable with that of CT images. It also provides consistent results on the quantitative measurement of cortical bone with CT images.

Detection of Co-Infection of Notocactus leninghausii f. cristatus with Six Virus Species in South Korea

Co-infection with two virus species was previously reported in some cactus plants. Here, we showed that Notocactus leninghausii f. cristatus can be co-infected with six different viruses: cactus mild mottle virus (CMMoV)-Nl, cactus virus X (CVX)-Nl, pitaya virus X (PiVX)-Nl, rattail cactus necrosis-associated virus (RCNaV)-Nl, schlumbergera virus X (SchVX)-Nl, and zygocactus virus X (ZyVX)-Nl. The coat protein sequences of these viruses were compared with those of previously reported viruses. CMMoV-Nl, CVX-Nl, PiVX-Nl, RCNaV-Nl, SchVX-Nl, and ZyVX-Nl showed the greatest nucleotide sequence homology to CMMoV-Kr (99.8% identity, GenBank accession NC_011803), CVX-Jeju (77.5% identity, GenBank accession LC12841), PiVX-P37 (98.4% identity, GenBank accession NC_024458), RCNaV (99.4% identity, GenBank accession NC_016442), SchVX-K11 (95.7% identity, GenBank accession NC_011659), and ZyVX-B1 (97.9% identity, GenBank accession NC_006059), respectively. This study is the first report of co-infection with six virus species in N. leninghausii f. cristatus in South Korea.

A pepper mottle virus-based vector enables systemic expression of endoglucanase D in non-transgenic plants

Plant-virus-based expression vectors have been used as an alternative to the creation of transgenic plants. Using a virus-based vector, we investigated the feasibility of producing the endoglucanase D (EngD) from Clostridium cellulovorans in Nicotiana benthamiana. This protein has endoglucanase, xylanase, and exoglucanase activities and may be of value for cellulose digestion in the generation of biofuels from plant biomass. The EngD gene was cloned between the nuclear inclusion b (NIb)- and coat protein (CP)-encoding sequences of pSP6PepMoV-Vb1. In vitro transcripts derived from the clone (pSP6PepMoV-Vb1/EngD) were infectious in N. benthamiana but caused milder symptoms than wild-type PepMoV-Vb1. RT-PCR amplification of total RNA from non-inoculated upper leaves infected with PepMoV-Vb1/EngD produced the target band for the CP, partial NIb and EngD-CP regions of PepMoV-V1/EngD, in addition to nonspecific bands. Western blot analysis showed the CP target bands of PepMoV-Vb1/EngD as well as non-target bands. EngD enzymatic activity in infected plants was detected using a glucose assay. The plant leaves showed increased senescence compared with healthy and PepMoV-Vb1-infected plants. Our study suggests the feasibility of using a viral vector for systemic infection of plants for expression of heterologous engD for the purpose of digesting a cellulose substrate in plant cells for biomass production.

ICTV Virus Taxonomy Profile: Virgaviridae

The family Virgaviridae is a family of plant viruses with rod-shaped virions, a ssRNA genome with a 3′-terminal tRNA-like structure and a replication protein typical of alpha-like viruses. Differences in the number of genome components, genome organization and the mode of transmission provide the basis for genus demarcation. Tobacco mosaic virus (genus Tobamovirus) was the first virus to be discovered (in 1886); it is present in high concentrations in infected plants, is extremely stable and has been extensively studied. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Virgaviridae, which is available at www.ictv.global/report/virgaviridae.

Ethanol Ablation of Ranulas: Short-Term Follow-Up Results and Clinicoradiologic Factors for Successful Outcome

BACKGROUND AND PURPOSE

Surgical excision of an affected sublingual gland for treatment of a ranula can carry a potential of a nerve damage or postoperative complications. However, there have been little studies about effective minimally invasive therapeutic method, yet. Our aim was to evaluate the efficacy and safety of ethanol ablation of ranulas and the clinicoradiologic factors that can predict outcome.

MATERIALS AND METHODS

This retrospective study evaluated 23 patients with ranulas treated by percutaneous ethanol ablation. Treatment outcome was assessed in 20 patients followed for at least 6 months. The duration of symptoms before ethanol ablation, pretreatment volume, and parapharyngeal extension on sonography and/or CT were correlated with the outcome. The Mann-Whitney U test and Fisher exact test were used for comparison of the factors according to the outcome.

RESULTS

The study evaluated 14 males and 9 females with a median age of 26 years (range, 3-41 years). Among 20 patients who were followed for at least 6 months (median, 20 months; range, 6-73 months), 9 patients (45%) demonstrated complete disappearance of the ranulas and 11 (55%) showed an incomplete response. When the patients were divided according to the duration of symptoms before ethanol ablation, the complete response rate was significantly higher in patients with ≤12 months of symptoms (73%, 8/11) than that in others (11%, 1/9) (P = .010). Pretreatment volume and parapharyngeal extension were not significantly different between the 2 groups.

CONCLUSIONS

Ethanol ablation is a safe and noninvasive treatment technique for ranulas with a significantly better outcome in patients with ≤12 months of symptoms. Therefore, it could be considered an alternative nonsurgical approach for ranulas with recent onset of symptoms.

Antiviral Activities of Trichothecenes Isolated from Trichoderma albolutescens against Pepper Mottle Virus

A bioassay-guided isolation using a green fluorescence protein (GFP)-tagged pepper mottle virus (PepMoV-GFP) based leaf-disk method to obtain new antiviral agents led to the isolation of trichodermin, 1, and a new compound trichoderminol, 2, from EtOAc extract of Trichoderma albolutescens culture medium. The structures of compounds 1 and 2 were determined by MS and NMR experiments, and the absolute configurations of the compounds were established by experimental and calculated vibrational circular dichroism spectra. Compounds 1 and 2 were evaluated for their anti-PepMoV potential in systemic host plants, such as tobacco and pepper, by PepMoV-GFP based systemic host method. All compounds exhibited inactivation effects against PepMoV. Furthermore, compound 1 showed protective effects against PepMoV.

Acetic acid chromoendoscopy for determining the extent of gastric intestinal metaplasia

BACKGROUND AND AIMS

The diagnosis of gastric intestinal metaplasia (IM) is currently performed by histologic assessment of multiple endoscopic biopsies, methylene blue chromoendoscopy, or narrow-band imaging with magnification. However, practical and readily available methods are lacking. We assessed the diagnostic accuracy and reproducibility of acetic acid chromoendoscopy (AAC) for determining the extent of gastric IM.

METHODS

One hundred twenty-six participants were enrolled. The participants underwent screening EGD with 1.5% acetic acid instillation for the detection of acetowhite reaction. Subsequently, targeted biopsies were performed at the 5 standard intra-gastric locations of the updated Sydney system. The accuracy of AAC was calculated using the histology results as a reference. Two endoscopists, each of whom was blinded to the other's result, determined the presence or absence of acetowhite reaction.

RESULTS

The overall diagnostic accuracy of AAC was 89.0%, and the sensitivity and specificity were 77.6% and 94.4%, respectively. The specificity for the gastric body was >94%. The proportion of extensive IM, a strong risk factor for gastric cancer, increased from 0.9% to 18.1% when AAC was used instead of conventional EGD alone (P < .001). Endoscopically determined atrophy had a negative effect on the diagnosis of AAC (odds ratio, 3.012; 95% confidence interval, 1.625-5.583). There was substantial inter- and intra-observer agreement.

CONCLUSIONS

AAC is a valid and reproducible tool for determining the extent of gastric IM and may serve as a practical method of identifying populations at high risk of gastric cancer. (Clinical trial registration number: NCT01499576.).

Improved Diagnostic Accuracy Using Arterial Phase CT for Lateral Cervical Lymph Node Metastasis from Papillary Thyroid Cancer

BACKGROUND AND PURPOSE

Contrast-enhanced CT protocols for papillary thyroid cancer are yet to be optimized. Our aim was to compare the diagnostic accuracy of arterial phase CT and delayed-phase CT protocols for lateral cervical lymph node metastasis from papillary thyroid carcinoma by using the lymph node tissue attenuation.

MATERIALS AND METHODS

This retrospective study included 327 lateral cervical lymph nodes (177 metastatic and 150 benign) from 131 patients with papillary thyroid carcinoma (107 initially diagnosed and 24 recurrences). Patients underwent CT by using 1 of 3 protocols: a 70-second (A) or a 35-second (B) delay with 100 mL of iodinated IV contrast or a 25-second delay with 75 mL of IV contrast (C). Two readers independently measured and compared lymph node tissue attenuation between metastatic and benign lymph nodes. An area under the receiver operating characteristic curve analysis was performed to differentiate metastatic and benign lymph nodes after multiple comparison correction for clustered data and was compared across the protocols.

RESULTS

The difference in mean lymph node tissue attenuation between metastatic and benign lymph nodes was maximum in protocol C (P < .001 for both readers). Protocol C showed the highest diagnostic performance (area under the receiver operating characteristic curve, 0.88-0.92) compared with protocol A (area under the receiver operating characteristic curve, 0.73-0.74, P < .001 for both readers) and B (area under the receiver operating characteristic curve, .63-0.65, P < .01 for both readers). The sensitivity, specificity, positive predictive value, and negative predictive value of lymph node tissue attenuation by using a 99-HU cutoff value were 83%-87%, 93.7%-97.9%, 95.1%-97.3%, and 81.2%-87%.

CONCLUSIONS

A combination of 25-second delay CT and 75 mL of iodinated IV contrast can improve the diagnostic accuracy for lateral lymph node metastasis from papillary thyroid carcinoma compared with a combination of a 35- or 70-second delay with 100-mL of iodinated IV contrast.

Simultaneous multiplex PCR detection of seven cucurbit-infecting viruses

Two multiplex polymerase chain reaction (PCR) systems using dual priming oligonucleotide (DPO) primers were developed for the simultaneous detection of seven cucurbit-infecting viruses. One system allows for the detection of papaya ringspot virus, watermelon mosaic virus, and zucchini yellow mosaic virus, whereas the other permits the detection of cucumber green mottle mosaic virus, cucumber fruit mottle mosaic virus, kyuri green mottle mosaic virus, and zucchini green mottle mosaic virus. Viral species-specific DPO primers developed in this study detected as little as 10 fg/μl of viral RNA under monoplex conditions and 10 pg/μl of viral RNA under multiplex conditions. Multiplex PCR using the DPO primer sets was capable of amplifying viral genes at annealing temperatures ranging from 53 °C to 63 °C. Whereas the use of conventional primers gave rise to non-specific bands, the DPO primers detected target viral genes in the absence of non-specific amplification. When these DPO multiplex primer sets were applied to virus-infected cucurbit samples obtained in the field, multiple infection as well as single infection was accurately identified. This novel approach could also detect multiple viruses in infected seeds. The reliability of multiplex PCR systems using DPO primers for plant virus detection is discussed.

Randomly detected genetically modified (GM) maize (Zea mays L.) near a transport route revealed a fragile 45S rDNA phenotype

Monitoring of genetically modified (GM) crops has been emphasized to prevent their potential effects on the environment and human health. Monitoring of the inadvertent dispersal of transgenic maize in several fields and transport routes in Korea was carried out by qualitative multiplex PCR, and molecular analyses were conducted to identify the events of the collected GM maize. Cytogenetic investigations through fluorescence in situ hybridization (FISH) of the GM maize were performed to check for possible changes in the 45S rDNA cluster because this cluster was reported to be sensitive to replication and transcription stress. Three GM maize kernels were collected from a transport route near Incheon port, Korea, and each was found to contain NK603, stacked MON863 x NK603, and stacked NK603 x MON810 inserts, respectively. Cytogenetic analysis of the GM maize containing the stacked NK603 x MON810 insert revealed two normal compact 5S rDNA signals, but the 45S rDNA showed a fragile phenotype, demonstrating a “beads-on-a-string” fragmentation pattern, which seems to be a consequence of genetic modification. Implications of the 45S rDNA cluster fragility in GM maize are also discussed.

Reverse Transcription Polymerase Chain Reaction-based System for Simultaneous Detection of Multiple Lily-infecting Viruses

A detection system based on a multiplex reverse transcription (RT) polymerase chain reaction (PCR) was developed to simultaneously identify multiple viruses in the lily plant. The most common viruses infecting lily plants are the cucumber mosaic virus (CMV), lily mottle virus (LMoV), lily symptomless virus (LSV). Leaf samples were collected at lily-cultivation facilities located in the Kangwon province of Korea and used to evaluate the detection system. Simplex and multiplex RT-PCR were performed using virus-specific primers to detect single-or mixed viral infections in lily plants. Our results demonstrate the selective detection of 3 different viruses (CMV, LMoV and LSV) by using specific primers as well as the potential of simultaneously detecting 2 or 3 different viruses in lily plants with mixed infections. Three sets of primers for each target virus, and one set of internal control primers were used to evaluate the detection system for efficiency, reliability, and reproducibility.

The effect of 5Hz high-frequency rTMS over contralesional pharyngeal motor cortex in post-stroke oropharyngeal dysphagia: a randomized controlled study

BACKGROUND

We sought to find the therapeutic effect of 5Hz high-frequency repetitive transcranial magnetic stimulation (rTMS) over the unaffected pharyngeal motor cortex in post-stroke dysphagic patients.

METHODS

Eighteen patients with unilateral hemispheric stroke oropharyngeal dysphagia that lasted more than 1 month were randomly divided into two groups. They all performed videofluoroscopic swallowing study (VFSS) before rTMS intervention. The experimental group (EG) received 5Hz rTMS over contra-lesional pharyngeal motor cortex for 10 min per day for 2 weeks. The control group (CG) received sham stimulation under the same condition. Videofluoroscopic swallowing study were performed again just after treatment cessation and 2 weeks afterward. The evaluation was performed using videofluoroscopic dysphagia scale (VDS) and penetration-aspiration scale (PAS).

KEY RESULTS

Mean baseline VDS and PAS of EG was 33.6 ± 12.1 and 3.41 ± 2.32 respectively and the scores were reduced to 25.3 ± 9.8 and 1.93 ± 1.52 just after 2 weeks intervention (P < 0.05). This effect lasted for up to 2 weeks after treatment. However, there was no change in the CG. Baseline prevalence of aspiration, pharyngeal residue, delayed triggering of pharyngeal swallowing and abnormal pharyngeal transit time (PTT) in EG was 66.7%, 66.7%, 33.3%, and 44.4%, respectively. After rTMS, the prevalence of aspiration and pharyngeal residue was reduced to 33.3% and 33.3%, respectively. However, the prevalence of delayed triggering and abnormal PTT was not changed.

CONCLUSIONS & INFERENCES

A 5Hz high-frequency rTMS on contra-lesional pharyngeal motor cortex might be beneficial for post-stroke dysphagic patients. This intervention can be used as a new treatment method in post-stroke patients with dysphagia.

Cecal fecaloma due to intestinal tuberculosis: endoscopic treatment

Colorectal fecaloma is a mass of accumulated feces that is much harder in consistency than a fecal impactation. The rectosigmoid area is the common site for fecalomas and the cecum is the most unusual site. Diagnosis is usually made by distinctive radiographic findings of a mobile intraluminal mass with a smooth outline and no mucosal attachment. Most of the fecalomas are successfully treated by conservative methods such as laxatives, enemas and rectal evacuation. When conservative treatments have failed, endoscopic procedures or a surgical intervention may be needed. We report here that a cecal fecaloma caused by intestinal tuberculosis scar was successfully removed by endoscopic procedures.

[A case of splenic pseudocyst complicated by acute pancreatitis]

Splenic pseudocyst is a rare disease associated with chronic and acute pancreatitis splenic pseudocyst is treated by distal pancreatectomy and splenectomy. A 47-year old woman with a 10-year history of alcohol abuse presented with epigastric and left upper quadrant pain of 3 days duration. Abdominal CT showed a 4.0×4.5 cm sized cystic lesion in the tail of the pancreas. Analgesics was administrated for the relief of abdominal pain. On the 4th hospital day, the patient complained more of left upper quadrant pain, so we took follow up CT scans. On follow up CT, one large splenic pseudocyst with size of 9.5×4.5×10.0 cm was noted. The patient was treated conservatively by percutaneous catheter drainage and discharged on the 13th hospital day. This case is the first case report of splenic pseudocyst treated conservatively, not by surgery in Korea.

Phylogeny, coat protein genetic variability, and transmission via seeds of Hosta Virus X

The complete genome of Hosta Virus X (HVX), which is thought to be a distinct species of Potexvirus, was sequenced. Nucleotide sequences of HVX were compared with those of other members of the genus Potexvirus and phylogenetic tree was constructed. The range of identities of viral replicase open reading frame 1 (ORF1) between HVX and other potexviruses were 43.1%-55.1% and 35.9%-46.6% at the nucleotide and amino acid levels, respectively. Phylogenetic analysis was performed according to the amino acid sequence of the replicase to determine the position of HVX in the genus Potexvirus. Results from the phylogenetic analysis demonstrated that HVX was in the same group as Cassava common mosaic virus (CsCMV), Plantago asiatica mosaic virus (PlAMV), Tulip virus X (TVX), and Hydrangea ring spot virus (HdRSV). In particular, coat protein (CP) sequences among viruses from different Hosta cultivars were revealed to be less variable than those from different isolates of Potato virus X (PVX), a Potexvirus type species. In the present study, HVX was transmissible by seeds of the Hosta "Blue Cadet" cultivar. Moreover, HVX was detected in the embryo but not in the seed coat or endosperm of the seed.

[Endoscopic findings and clinical significance of portal hypertensive colopathy]

BACKGROUND/AIMS

The endoscopic findings and clinical relevance of portal hypertensive colopathy are not well described in Korea. We aimed to do a retrospective study of mucosal changes in the colon of patients with liver cirrhosis and to find their association with clinical characteristics.

METHODS

We reviewed the clinical data and endoscopic findings of 48 patients with liver cirrhosis and 48 patients, matched for age and sex, with irritable bowel disease (IBS) who underwent colonoscopy over a 5 year span.

RESULTS

Patients with liver cirrhosis were more likely to have colitis-like lesions and vascular abnormalities than IBS patients. Low platelet count (p=0.005) and severe esophageal varices (p=0.011) were associated with portal hypertensive colopathy, whereas the etiologies and severity of cirrhosis were not associated with these findings.

CONCLUSIONS

Portal hypertensive colopathy can be defined with colitis-like lesions or vascular lesions. These lesions are more frequently present in patients with more severe esophageal varices and thrombocytopenia.

The complete genome sequence of a member of a new species of tobamovirus (rattail cactus necrosis-associated virus) isolated from Aporcactus flagelliformis

In this study, we identified a new tobamovirus from diseased Aporcactus flagelliformis cactus plants, named it rattail cactus necrosis-associated virus (RCNaV), and determined its complete genome sequence. The full RCNaV genome consisted of 6,506 nucleotides and contained four open reading frames coding for proteins of M(r) 128 kDa (3,441 nt), 185 kDa (4,929 nt), 55 kDa (1452 nt), 36 kDa (1,005 nt) and 19 kDa (513 nt) from the 5' to 3' end, respectively. The overall similarities for the four ORFs of RCNaV were from 32.5% to 64.1% and from 17.0% to 67.3% to those of the other tobamoviruses, at the nucleotide and amino acid level, respectively. Comparison of the coding and non-coding regions of the virus with those of other tobamoviruses showed that RCNaV is the most closely related to cactus mild mottle virus.

Detection of transgene in early developmental stage by GFP monitoring enhances the efficiency of genetic transformation of pepper

In order to establish a reliable and highly efficient method for genetic transformation of pepper, a monitoring system featuring GFP (green fluorescent protein) as a report marker was applied to Agrobacterium-mediated transformation. A callus-induced transformation (CIT) system was used to transform the GFP gene. GFP expression was observed in all tissues of T(0), T(1) and T(2) peppers, constituting the first instance in which the whole pepper plant has exhibited GFP fluorescence. A total of 38 T(0) peppers were obtained from 4,200 explants. The transformation rate ranged from 0.47 to 1.83% depending on the genotype, which was higher than that obtained by CIT without the GFP monitoring system. This technique could enhance selection power by monitoring GFP expression at the early stage of callus in vitro. The detection of GFP expression in the callus led to successful identification of the shoot that contained the transgene. Thus, this technique saved lots of time and money for conducting the genetic transformation process of pepper. In addition, a co-transformation technique was applied to the target transgene, CaCS (encoding capsaicinoid synthetase of Capsicum) along with GFP. Paprika varieties were transformed by the CaCS::GFP construct, and GFP expression in callus tissues of paprika was monitored to select the right transformant.

Development of infectious transcripts from full-length and GFP-tagged cDNA clones of Pepper mottle virus and stable systemic expression of GFP in tobacco and pepper

A full-length cDNA clone (pSP6PepMoV-Vb1) of the genomic RNA of a Korean isolate of Pepper mottle virus (PepMoV-Vb1) was constructed downstream of a bacteriophage SP6 RNA polymerase promoter in the plasmid. In vitro RNA transcripts generated from pSP6PepMoV-Vb1 corresponded to PepMoV-Vb1 RNA (9641nt) with an extra guanosine residue at the 5' terminus and a 15-nt, poly (A) tract at the 3' end. The RNAs synthesized from the pSP6PepMoV-Vb1 clone, by in vitro run-off transcription in the presence of the 5' cap analog m(7)GpppG, were highly infectious in Nicotiana benthamiana and Capsicum annuum cv. Early Calwonder. Visible symptoms appeared at 4-5 days post-inoculation, at essentially the same time as occurred on these host plant species inoculated with wild-type PepMoV-Vb. Symptoms induced by progeny virus of the transcripts were indistinguishable from wild-type PepMoV-Vb on their experimental and natural hosts. The gene encoding the green fluorescent protein (GFP), turboGFP, was inserted between the coding regions for NIb and CP in the pSP6PepMoV-Vb1 clone. RNA transcripts of the resulting GFP-tagged clone, designated SP6PepMoV-Vb1/GFP, were highly infectious and symptoms were not different from those induced by either transcripts of pSP6PepMoV-Vb1 or wild-type PepMoV-Vb. However, GFP expression could be detected earlier than virus-induced symptom in plants infected by SP6PepMoV-Vb1/GFP. This study is the first report of the construction of a biologically active, full-length cDNA copy of the Pepper mottle virus RNA genome and the stable expression of a foreign gene within the modified virus.

The complete genome sequence and genome structure of frangipani mosaic virus

In this study, the complete sequence of the genomic RNA of frangipani mosaic virus (FrMV) has been determined and compared to those of other known tobamoviruses. The complete genome sequence of FrMV consisted of 6,643 nucleotides. The FrMV genomic RNA encoded four open reading frames (ORFs), for proteins of M(r) 128 kDa (1,147 aa), 186 kDa (1,651 aa), 30 kDa (257 aa) and 18 kDa (175 aa) from the 5' to the 3' end. Overall similarities for the four ORFs of FrMV-P ranged from 26.8 to 53.0% at the amino acid level when compared to those of 24 other tobamoviruses. Phylogenetic analysis of the FrMV replicase (186 kDa) and MP revealed that FrMV is closely related to SHMV and CMMoV, while the FrMV replicase (128 kDa) is more closely related to cucurbit-infecting and malvaceous-infecting tobamoviruses, and the FrMV CP is closely related to that of CMMoV and solanaceous-infecting tobamoviruses.

The complete genome sequence of freesia mosaic virus and its relationship to other potyviruses

We have completed the genomic sequence of a potyvirus, freesia mosaic virus (FreMV), and compared it to those of other known potyviruses. The full-length genome sequence of FreMV consists of 9,489 nucleotides. The large protein contains 3,077 amino acids, with an AUG start codon and UAA stop codon, containing one open reading frame typical of a potyvirus polyprotein. The polyprotein of FreMV-Kr gives rise to eleven proteins (P1, HC-pro, P3, PIPO, 6K1, CI, 6K2, VPg, NIa, NIb and CP), and putative cleavage sites of each protein were identified by sequence comparison to those of other known potyviruses. Phylogenetic analysis of the polyprotein revealed that FreMV-Kr was most closely related to PeMoV and was related to BtMV, BaRMV and PeLMV, which belong to the BCMV subgroup. This is the first information on the complete genome structure of FreMV, and the sequence information clearly supports the status of FreMV as a member of a distinct species in the genus Potyvirus.

Risk of hemorrhagic gastropathy associated with colonoscopy bowel preparation using oral sodium phosphate solution

BACKGROUND AND STUDY AIMS

Oral sodium phosphate (NaP) solution is widely used for colonoscopy bowel preparation and it may cause aphthous ulcers in the colon. Our aim was to evaluate whether oral NaP solution is associated with gastric mucosal lesions.

METHODS

A total of 20 070 individuals underwent esophagogastroduodenoscopy (EGD) with colonoscopy, and 4271 individuals underwent EGD without colonoscopy, for cancer screening. Oral NaP solutions were used for bowel preparation prior to colonoscopy. Hemorrhagic gastropathy was graded using a five-point scale for erosive mucosal injury. The effect of NaP bowel preparation on hemorrhagic gastropathy was estimated using multiple logistic regression analysis with odds ratios (ORs) and 95 % confidence intervals (CIs).

RESULTS

The incidence of hemorrhagic gastropathy was 1.6 % (70/4271) in the EGD only group and 4.0 % (809/20 070) in the EGD with colonoscopy group ( P < 0.001, unadjusted OR 2.55, 95 %CI 1.99 - 3.27). The ORs for mild (grade 1 - 2), moderate (grade 3), and severe (grade 4) hemorrhagic gastropathy according to NaP use were 1.92 (95 %CI 1.45 - 2.54), 4.72 (95 %CI 2.65 - 8.47), and 5.99 (95 %CI 1.46 - 24.63), respectively. After adjustment for confounding factors, NaP solution was a significant risk factor for acute hemorrhagic gastropathy in the multivariate analysis (OR 1.92, 95 %CI 1.34-2.74). In addition, male sex, a body mass index (kg/m (2)) of less than 20, concurrent use of antihypertensive or nonsteroidal anti-inflammatory drugs, and duodenal ulcers were independently associated with the development of hemorrhagic gastropathy. HELICOBACTER PYLORI infection and atrophic gastritis were negatively associated with hemorrhagic gastropathy.

CONCLUSION

Oral NaP bowel preparation for colonoscopy was associated with hemorrhagic gastropathy.

Subcellular localization of the barley stripe mosaic virus triple gene block proteins

Barley stripe mosaic virus (BSMV) spreads from cell to cell through the coordinated actions of three triple gene block (TGB) proteins (TGB1, TGB2, and TGB3) arranged in overlapping open reading frames (ORFs). Our previous studies (D. M. Lawrence and A. O. Jackson, J. Virol. 75:8712-8723, 2001; D. M. Lawrence and A. O. Jackson, Mol. Plant Pathol. 2:65-75, 2001) have shown that each of these proteins is required for cell-to-cell movement in monocot and dicot hosts. We recently found (H.-S. Lim, J. N. Bragg, U. Ganesan, D. M. Lawrence, J. Yu, M. Isogai, J. Hammond, and A. O. Jackson, J. Virol. 82:4991-5006, 2008) that TGB1 engages in homologous interactions leading to the formation of a ribonucleoprotein complex containing viral genomic and messenger RNAs, and we have also demonstrated that TGB3 functions in heterologous interactions with TGB1 and TGB2. We have now used Agrobacterium tumefaciens-mediated protein expression in Nicotiana benthamiana leaf cells and site-specific mutagenesis to determine how TGB protein interactions influence their subcellular localization and virus spread. Confocal microscopy revealed that the TGB3 protein localizes at the cell wall (CW) in close association with plasmodesmata and that the deletion or mutagenesis of a single amino acid at the immediate C terminus can affect CW targeting. TGB3 also directed the localization of TGB2 from the endoplasmic reticulum to the CW, and this targeting was shown to be dependent on interactions between the TGB2 and TGB3 proteins. The optimal localization of the TGB1 protein at the CW also required TGB2 and TGB3 interactions, but in this context, site-specific TGB1 helicase motif mutants varied in their localization patterns. The results suggest that the ability of TGB1 to engage in homologous binding interactions is not essential for targeting to the CW. However, the relative expression levels of TGB2 and TGB3 influenced the cytosolic and CW distributions of TGB1 and TGB2. Moreover, in both cases, localization at the CW was optimal at the 10:1 TGB2-to-TGB3 ratios occurring in virus infections, and mutations reducing CW localization had corresponding effects on BSMV movement phenotypes. These data support a model whereby TGB protein interactions function in the subcellular targeting of movement protein complexes and the ability of BSMV to move from cell to cell.

Complete sequence and genome structure of cactus mild mottle virus

We have completed the genomic sequence of a tobamovirus, cactus mild mottle virus (CMMoV), and compared it to those of other known tobamoviruses. The complete genome sequence of CMMoV consists of 6,449 nucleotides. The genome RNA of the virus contains four open reading frames, encoding, from the 5' to the 3' end, the 120-kDa viral replicase, the 186-kDa viral polymerase, the 33-kDa movement protein and the 18-kDa coat protein. Overall amino acid similarities for the four viral proteins of CMMoV ranged from 16.3 to 44.4% compared to those of 20 other tobamoviruses. Phylogenetic analysis of the viral replicases and MP revealed that CMMoV is closely related to cucurbit-infecting tobamoviruses, while the CMMoV CP is more closely related to brassica- and solanaceous-infecting tobamoviruses.

The role of the Cucumber mosaic virus 2b protein in viral movement and symptom induction

The Cucumber mosaic virus (CMV) 2b protein is a counter-defense factor and symptom determinant. Conserved domains in the 2b protein sequence were mutated in the 2b gene of strain Fny-CMV. The effects of these mutations were assessed by infection of Nicotiana tabacum, N. benthamiana, and Arabidopsis thaliana (ecotype Col-0) with mutant viruses and by expression of mutant 2b transgenes in A. thaliana. We confirmed that two nuclear localization signals were required for symptom induction and found that the N-terminal domain was essential for symptom induction. The C-terminal domain and two serine residues within a putative phosphorylation domain modulated symptom severity. Further infection studies were conducted using Fny-CMVdelta2b, a mutant that cannot express the 2b protein and that induces no symptoms in N. tabacum, N. benthamiana, or A. thaliana ecotype Col-0. Surprisingly, in plants of A. thaliana ecotype C24, Fny-CMVdelta2b induced severe symptoms similar to those induced by the wild-type virus. However, C24 plants infected with the mutant virus recovered from disease while those infected with the wild-type virus did not. Expression of 2b transgenes from either Fny-CMV or from LS-CMV (a mild strain) in Col-0 plants enhanced systemic movement of Fny-CMVdelta2b and permitted symptom induction by Fny-CMVdelta2b. Taken together, the results indicate that the 2b protein itself is an important symptom determinant in certain hosts. However, they also suggest that the protein may somehow synergize symptom induction by other CMV-encoded factors.

Transgenic peppers that are highly tolerant to a new CMV pathotype

The CMV (cucumber mosaic virus) is the most frequently occurring virus in chili pepper farms. A variety of peppers that are resistant to CMVP0 were developed in the middle of 1990s through a breeding program, and commercial cultivars have since been able to control the spread of CMVP0. However, a new pathotype (CMVP1) that breaks the resistance of CMVP0-resistant peppers has recently appeared and caused a heavy loss in productivity. Since no genetic source of this new pathotype was available, a traditional breeding method cannot be used to generate a CMVP1-resistant pepper variety. Therefore, we set up a transformation system of pepper using Agrobacterium that had been transfected with the coat protein gene, CMVP0-CP, with the aim of developing a new CMVP1-resistant pepper line. A large number of transgenic peppers (T(1), T(2) and T(3)) were screened for CMVP1 tolerance using CMVP1 inoculation. Transgenic peppers tolerant to CMVP1 were selected in a plastic house as well as in the field. Three independent T(3) pepper lines highly tolerant to the CMVP1 pathogen were found to also be tolerant to the CMVP0 pathogen. These selected T(3) pepper lines were phenotypically identical or close to the non-transformed lines. However, after CMVP1 infection, the height and fruit size of the non-transformed lines became shorter and smaller, respectively, while the T(3) pepper lines maintained a normal phenotype.

Generation of infectious transcripts from Korean strain and mild mottle strain of potato virus X

Full-length cDNAs of two different strains of Potato virus X (PVX-Kr and PVX-Mo) have been directly amplified by long template reverse transcription polymerase chain reaction (RT-PCR) using the 5'-end primer containing a SP6 or T7 RNA promoter sequence and the virus-specific 3'-end primer, and then constructed in plasmid vectors. Capped in vitro transcripts from cloned full-length cDNAs as well as those RT-PCR amplicons proved to be infectious systemically on tobacco plants. Symptom expression on tobacco plants from PVX-Mo transcripts was faster and severer than that from PVX-Kr. In replication stability test of transcripts derived from PVX clones, progeny viruses showed stable replication according to sequencing through passages. This highly infectious transcript system from the full-length cDNA clones for PVX can be useful for recombinant molecules for functional analysis of viral proteins in plant-virus interaction study as well as for expression of foreign protein in planta.

Distinct locomotive patterns of granulocytes, monocytes and lymphocytes in a stable concentration gradient of chemokines

The pattern of leukocyte locomotion can be changed in many pathological situations, but its accurate analysis is difficult because of technological limitation. In the present study, by using a newly developed time-lapse videomicroscopic technique, we have analyzed the locomotive patterns of leukocytes in a stable concentration gradient of chemokines. Granulocytes, monocytes, and lymphocytes were purified from adult human peripheral blood. Locomotive behavior of the leukocytes was analyzed by an optical assay using a microchannel producing a stable concentration gradient of chemokines. Videomicroscopic analysis showed distinct locomotive patterns of granulocytes, monocytes, and lymphocytes. Granulocytes were intrinsically motile, vigorously moving in random direction without any chemokine stimulation. Upon stimulation with CXCL8/IL-8, the speed of migration was increased from 13.3 +/- 2.8 to 19.4 +/- 2.5 microm/min (P = 0.002, n = 100) and they moved toward the chemokine, although many cells still wandered very much. Stimulation with CCL5/RANTES or CXCL12/SDF-1alpha induced similar changes in locomotive pattern. On the other hand, most lymphocytes did not polarize or move spontaneously without chemokine stimulation. Stimulation with CXCL12 induced directional migration in 37% of the lymphocytes at a speed of 9.6 +/- 1.6 microm/min (n = 100). The movement pattern of monocytes was similar to that of granulocytes in that they tend to become polarized and move spontaneously, but they moved at a very slow speed ranging from 3.9 to 4.2 microm/min even with chemokine stimulation. The new optical assay may be useful for many diagnostic as well as basic studies.

Abnormal cell division caused by inclusion bodies in E. coli; increased resistance against external stress

Inclusion body formation occurs naturally in prokaryotic cells, but is particularly common when heterologous foreign proteins are overexpressed in bacterial systems. The plant disease virus protein CMV 3a (cucumber mosaic virus movement protein) and the 56 kDa Orientia tsutsugamushi (OT56) protein (an outer membrane protein), which causes tsutsugamushi disease, were expressed in Escherichia coli, and found to form inclusion bodies. Confocal laser scanning microscopy revealed that these inclusion bodies are localized at the cellular poles within E. coli. Cells expressing inclusion bodies appeared to be interconnected, and divided abnormally. The clustered cells exhibited biofilm-like characteristics in that the interior cells of the community were protected by the antibiotic resistance of the outer cells. We compared the number of colony-forming units in inclusion body-forming versus non-forming E. coli to demonstrate the effects of lysozyme, sonication or antibiotic treatment. E. coli clustering provided significantly improved protection against cell disruption/lysis by physical and biochemical stress. This is the first report that shows that abnormal cell division caused by inclusion body formation can cause cellular clustering, resulting in improved resistance to stress in vitro.

Environmental risk assessment of genetically engineered herbicide-tolerant Zoysia japonica

Herbicide-tolerant Zoysia grass (Zoysia japonica Steud.) has been generated previously through Agrobacterium tumefaciens-mediated transformation. The genetically modified (GM) Zoysia grass survived Basta spraying and grew to maturity normally while the wild-type (WT) grass stopped growing and died. GM Zoysia grass will permit more efficient weed control for various turf grass plantings such as home lawns, golf courses, and parks. We examined the environmental/biodiversity risks of herbicide-tolerant GM Zoysia before applying to regulatory agencies for approval for commercial release. The GM and WT Zoysia grass' substantial trait equivalence, ability to cross-pollinate, and gene flow in confined and unconfined test fields were selectively analyzed for environmental/biodiversity effects. No difference between GM and WT Zoysia grass in substantial traits was found. To assess the potential for cross-pollination and gene flow, a non-selective herbicide, Basta, was used. Results showed that unintended cross-pollination with and gene flow from GM Zoysia grass were not detected in neighboring weed species examined, but were observed in WT Zoysia grass (on average, 6% at proximity, 1.2% at a distance of 0.5 m and 0.12% at a radius of 3 m, and 0% at distances over 3 m). On the basis of these initial studies, we conclude that the GM Zoysia grass generated in our laboratory and tested in the Nam Jeju County field does not appear to pose a significant risk when cultivated outside of test fields.

Complete genome sequence supports bell pepper mottle virus as a species of the genus Tobamovirus

Biological properties and the complete genome sequence of bell pepper mottle virus (BPeMV) were determined. The full genome of BPeMV consists of 6375 nucleotides. The BPeMV genomic RNA has four open reading frames (ORFs) encoding proteins of M(r) 126, 181, 30 and 18 kDa from the 5' to the 3' end, respectively. The lengths of the 5' nontranslated region (NTR) and the 3' NTR are 71 and 198 nucleotides, respectively. Overall identities for the four ORFs of BpeMV, at the nucleotide and amino acid levels, respectively, ranged from 36.0 to 80.6% and from 32.1 to 90.9%, compared to those of 22 other tobamoviruses. The CP gene of BPeMV displayed 43.5-73.5% and 32.1-82.4% identity to those of 22 other tobamoviruses at the nucleotide and amino acid levels, respectively. Phylogenetic analyses of four viral proteins clearly supported the conclusion that BPeMV-encoded proteins were related to those of members of the Solanaceae-infecting tobamoviruses. BPeMV was closely related to tomato mosaic virus, and tobacco mosaic virus and different from other tobamoviruses. Western blot analysis showed that BPeMV cross-reacted strongly with antibodies against members of Solanaceae-infecting tobamoviruses. These data represent the first molecular evidence supporting BPeMV as a separate species of the genus Tobamovirus.

Infection of soybean by cucumber mosaic virus as determined by viral movement protein

To characterize the host range determinant of the soybean strain of Cucumber mosaic virus (CMV) we analyzed a series of pseudorecombinants and chimeric viruses between infectious transcripts from two soybean strains (CMV-SC and CMV-SD) and an ordinary strain (CMV-Y). CMV-Y could not infect soybeans, even locally. Systemic infection of the two soybean-adapted soybean isolates on soybean plants mapped to RNA3. Chimeric RNA3s from between CMV-SC and CMV-Y, and chimeric RNA3s from between CMV-SC and CMV-SD, were made and inoculated onto wild soybean Iwate and soybean cv. Tsurunoko. The 3a region determined the viral systemic movement in the plants. In the wild soybean ecotype Hyougo, cell-to-cell movement of two different CMV soybean strains, one of which infects systemically while the other does not, in the inoculated leaves were almost the same, suggesting that the resistance of soybean operates at the level of long-distance movement. Our results clearly suggest that movement protein is a host determinant of CMV soybean strains.

Molecular evidence supporting the confirmation of maracuja mosaic virus as a species of the genus Tobamovirus and production of an infectious cDNA transcript

The complete genome sequence of maracuja mosaic virus (MarMV) was determined and analyzed. The full MarMV genome consisted of 6794 nucleotides, and this is the largest genome size among known tobamoviruses. The MarMV genome RNA contained four open reading frames (ORFs) coding for proteins of M(r) 126, 181, 34 and 18 kDa from the 5' to 3' end, respectively. The lengths of the 5' nontranslated region (NTR) and the 3' NTR were 54 and 177 nucleotides, respectively. Phylogenetic tree analysis revealed that these MarMV-encoded proteins are related to members of the Malvaceae- and Cucurbitaceae-infecting tobamoviruses. MarMV is different from other tobamoviruses and forms a new Passifloraceae-infecting subgroup. Western blot analysis showed that MarMV cross-reacted strongly with antibodies against Kyuri green mottle mosaic virus and Hibiscus latent Singapore virus. Synthesized capped transcripts from full-length cDNA of MarMV were infectious. These data clearly indicate that MarMV belongs to a separate species of the genus Tobamovirus.

Pepper mild mottle virus pathogenicity determinants and cross protection effect of attenuated mutants in pepper

To determine the pathogenicity domain and to apply cross protection, Pepper mild mottle virus (PMMoV) point-mutations in the replicase (REP) gene between the methyl-transferase and helicase domains, and deletions truncating pseudoknots in the 3' non-coding region (NCR), were constructed. Some mutants substituting a single amino acid in REP residue 348 exhibited mild symptoms in Nicotiana benthamiana or pepper plants. Accumulation of these mutants was higher than that of other REP mutants or wild-type PMMoV. Deletion mutants in the 3' NCR pseudoknot showed the lowest virus replication and accumulation among the mutants tested. Six attenuated mutants, which combined 3' NCR deletions and single or double REP substitution mutations were constructed to investigate cross protection effects on pepper plants. All six of the attenuated mutants showed milder symptom development than wild-type virus. These results suggest that REP and the pseudoknot in the 3' NCR are major pathogenicity determinants of the virus, and engineered PMMoV attenuated mutants can be useful for protection against the virus in pepper plants.

The complete genome sequence of pepper severe mosaic virus and comparison with other potyviruses

The complete nucleotide sequence of pepper severe mosaic virus (PepSMV) was determined. The viral genome consisted of 9890 nucleotides, excluding a poly (A) tract at the 3' end of the genome. The PepSMV RNA genome encoded a single polyprotein of 3085 amino acid residues, resulting in ten functionally distinct potyviral proteins. The lengths of the 5' nontranslated region (NTR) and the 3' NTR were 164 and 468 nucleotides, respectively. The genome organization of the virus was typical for members of the genus Potyvirus in the family Potyviridae. The coat protein amino acid sequence identity between PepSMV and the other 45 potyviruses ranged from 53.4 to 79.7%. Sequence alignments and phylogenetic analyses of the potyviral polyprotein sequences revealed that PepSMV was the closest to potato virus Y (PVY) and closely related to members of the PVY subgroup. Our genome sequence data clearly confirmed that PepSMV belongs to a separate species in the genus Potyvirus.

In vitro and in planta interaction evidence between Nicotiana tabacum thaumatin-like protein 1 (TLP1) and cucumber mosaic virus proteins

Using a yeast two-hybrid system, we identified a plant cellular factor that interacts with the proteins of the Cucumber mosaic virus (CMV). Initially 14 candidate genes were isolated from Nicotiana tabacum, using a full-length CMV 1a gene as bait. Among the candidate genes, two were encoding thaumatin-like proteins (TLP), and were designated as Nicotiana tabacum thaumatin-like protein 1 (NtTLP1). Consistent with this observation, recombinant GST-NtTLP1 protein, which was expressed and purified in E. coli, bound tightly to CMV 1a in vitro. In planta interaction was also verified via co-immunoprecipitation. Additionally, NtTLP1 specifically interacted with the CMV movement-related proteins, movement protein and coat protein, in yeast. Real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that the expression of NtTLP1 increased as the result of CMV inoculation.

Genetic mapping of the compatibility between a lily isolate of Cucumber mosaic virus and a satellite RNA

Five isolates of Cucumber mosaic virus (CMV) from Lilium sp. (lily), which were isolated from specimens in Japan, Korea and Taiwan, were unable to support satellite RNA (satRNA) accumulation. In order to map the CMV sequences that are involved in satRNA support, HL-CMV (Japanese lily isolate), Y-CMV (ordinary strain) and Y-satellite RNA (Y-sat) were used as the source material. The pseudorecombinants between Y-CMV and HL-CMV revealed that RNA1 was essential for satRNA replication in lily. The results of chimeric constructs and various mutations showed that two amino acid residues (at positions 876 and 891) in the 1a protein were the determinants for the inability of HL-CMV to support a satRNA. Specifically, Thr at position 876 had a more pronounced effect than Met at position 891. Specific changes in RNA sequence were also detected in the 3' terminus of Y-sat and these particular alterations allowed it to be supported by HL-CMV. It is believed that, through evolution, the adaptation of CMV to lily resulted in the introduction of amino acid changes in the 1a protein, changes that coincidentally affected the ability of lily CMV to support satRNAs.

Emergence of Rsv-resistance breaking Soybean mosaic virus isolates from Korean soybean cultivars

Twelve Rsv resistance-breaking (RB) isolates of Soybean mosaic virus (SMV) were obtained from field-grown soybean plants showing mosaic symptoms and subsequently examined biologically and molecularly. All of these RB isolates were identified as SMV based on serological and infectivity assays, and the amplification of P1 gene products by reverse transcription-polymerase chain reaction (RT-PCR). Differential soybean cultivars, lines or accessions Lee 68 (rsv), PI 96983, York, Marshall, Ogden, Kwanggyo, Suweon 97 (Rsv1 alleles), L29 (Rsv3), and V94-5152 (Rsv4), following inoculation with each RB isolate, showed similar systemic symptoms suggesting that these RB isolates can overcome Rsv resistance at three loci. To differentiate the 12 RB isolates molecularly, the P1 coding region for each isolate was amplified, cloned, sequenced and compared to known SMV strains. The P1 region from the RB isolates shared 86-90% and 90-99% similarities in amino acid (aa) and nucleotide sequence, respectively, with known SMV strains. Comparison of aa sequences indicated that these RB isolates are newly emerging isolates capable of breaking Rsv resistance. Phylogenetic analysis further suggested that the RB isolates can be classified as three major types. However, recombination was not observed within the coding region of P1 protein among the types. This is the first report on the emergence of SMV isolates capable of overcoming all of the known resistance alleles at the Rsv1 locus, as well as distinct resistance genes at Rsv3 and Rsv4.