Multifunctional chemical inhibitors of the florigen activation complex discovered by structure-based high-throughput screening.

Structure-based high-throughput screening of chemical compounds that target protein-protein interactions (PPIs) is a promising technology for gaining insight into how plant development is regulated, leading to many potential agricultural applications. At present, there are no examples of using high-throughput screening to identify chemicals that target plant transcriptional complexes, some of which are responsible for regulating multiple physiological functions. Florigen, a protein encoded by FLOWERING LOCUS T (FT), was initially identified as a molecule that promotes flowering and has since been shown to regulate flowering and other developmental phenomena such as tuber formation in potato (Solanum tuberosum). FT functions as a component of the florigen activation complex (FAC) with a 14-3-3 scaffold protein and FD, a bZIP transcription factor that activates downstream gene expression. Although 14-3-3 is an important component of FAC, little is known about the function of the 14-3-3 protein itself. Here, we report the results of a high-throughput in vitro fluorescence resonance energy transfer (FRET) screening of chemical libraries that enabled us to identify small molecules capable of inhibiting FAC formation. These molecules abrogate the in vitro interaction between the 14-3-3 protein and the OsFD1 peptide, a rice (Oryza sativa) FD, by directly binding to the 14-3-3 protein. Treatment with S4, a specific hit molecule, strongly inhibited FAC activity and flowering in duckweed, tuber formation in potato, and branching in rice in a dose-dependent manner. Our results demonstrate that the high-throughput screening approach based on the three-dimensional structure of PPIs is suitable in plants. In this study, we have proposed good candidate compounds for future modification to obtain inhibitors of florigen-dependent processes through inhibition of FAC formation.

Endoscopic ultrasound­guided biliary drainage in patients with surgically altered anatomy: a systematic review and Meta­analysis.

BACKGROUND AND AIMS: Endoscopic retrograde cholangiopancreatography is technically challenging to perform in patients with surgically altered anatomy (SAA). For these patients, endoscopic ultrasound-guided biliary drainage (EUS-BD) is one of the good indications. The aim of our systematic review and meta-analysis was to identify and evaluate evidence of the efficacy and safety of EUS-BD in patients with SAA. METHODS: A systematic review of the PubMed was conducted through to December 2021 to identify studies performing EUS-BD in patients with SAA. The primary outcome was the pooled technical success proportion in patients with SAA. The pooled clinical success and adverse event proportions in patients with SAA were also analyzed. RESULTS: The search identified 1195 possible records, with 18 studies meeting our criteria for analysis, reporting data for 409 patients with SAA who underwent EUS-BD. The pooled technical success, clinical success and adverse event proportions in patients with SAA were 97.8% (95% confidence interval [CI], 95.8-99.7%), 94.9% (95% CI, 91.8-98.1%), and 12.8% (95% CI, 7.4-18.1%), respectively. CONCLUSIONS: EUS-BD is effective for patients with SAA. However, adverse events should be considered when performing EUS-BD in these patients.

Can endoscopic retrograde cholangiopancreatography-related procedures for resolving acute cholangitis be effectively and safely performed in patients with surgically altered anatomy? Comparison study to evaluate the timing of short-type single-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography.

OBJECTIVES: Balloon enteroscopy (BE)-assisted endoscopic retrograde cholangiopancreatography (ERCP)-related procedures to resolve acute cholangitis (AC) in patients with surgically altered anatomy (SAA) are limited. There is a lack of evidence on whether the timing of BE-assisted ERCP affects clinical outcomes in patients with AC. This study aimed to evaluate the clinical outcomes of short-type single-balloon enteroscopy (short SBE)-assisted ERCP in patients with SAA and AC. METHODS: Patients with AC who underwent short SBE-assisted ERCP procedures between September 2011 and April 2022 were retrospectively reviewed. The outcomes of procedures undergone at ≤24 h and >24 h were compared. The primary outcome was the length of stay (LOS). RESULTS: Overall, 56 patients underwent procedures at ≤24 h, and 58 patients at >24 h. The procedural success and adverse event rates of short SBE-assisted ERCP were 87.7% (95% confidence interval [CI] 80.3-93.1%) and 4.4% (95% CI 1.4-9.9%), respectively. Patients with severe (Grade III) AC and systemic inflammatory response syndrome were more in early (at ≤24 h) ERCP groups. LOS and median time from ERCP procedures to discharge were shorter in the early group. Procedural success and adverse event rates between both groups had no significant differences. Multivariable linear regression analysis showed that ERCP performed at ≤24 h was associated with shorter LOS, while severe cholangitis and malignant biliary obstruction were associated with longer LOS. CONCLUSIONS: Short SBE-assisted ERCP is effective and safe in patients with SAA and AC. Early procedures seemed to attribute early improvement of general condition, thus shortening the LOS.

Effectiveness of clip-and-thread traction-assisted duodenal endoscopic submucosal dissection: a propensity score-matched study (with video).

BACKGROUND AND AIMS: The indications for endoscopic submucosal dissection (ESD) in superficial nonampullary duodenal epithelial tumors (SNADETs) remain controversial because the procedure is technically challenging. Moreover, the effectiveness of clip-and-thread traction-assisted ESD (TA-ESD) for SNADETs has not been assessed. The aim of the current study was to compare the effectiveness of duodenal TA-ESD and conventional ESD for SNADETs. METHODS: SNADETs treated with conventional ESD or TA-ESD between April 2017 and March 2021 at Saitama Medical University International Medical Center were evaluated retrospectively. RESULTS: There were 49 cases of conventional ESD and 32 cases of TA-ESD for SNADETs. Using a propensity score-matched design, we selected 26 pairs of cases with conventional ESD and TA-ESD. In the unmatched cohort, patients treated with TA-ESD were characterized by a higher R0 (no tumor identified at the lateral or vertical margins) resection rate (P = .004), more frequent poor submucosal lifting because of fibrosis (P = .014), and shorter follow-up period (P = .0004) than patients treated with conventional ESD. In the propensity score-matched pairs, patients treated with TA-ESD were characterized by a higher rate of R0 resection (P = .021) and a shorter follow-up period (P = .0061). The findings regarding R0 resection rates were confirmed by multivariate logistic regression models, which found a higher odds ratio (OR) for R0 resection in patients who underwent TA-ESD than in patients who underwent conventional ESD both in the unmatched cohort (OR, 17.0; 95% confidence interval, 1.6-178.8; P = .018) and in the propensity score-matched pairs (OR, 26.7; 95% confidence interval, 1.5-460.2; P = .024). CONCLUSIONS: Our findings suggest TA-ESD may increase the rate of R0 resection in patients with SNADETs in comparison with conventional ESD.

Factors affecting complete stone extraction in the initial procedure in short type single-balloon enteroscopy-assisted endoscopic retrograde cholangiography for patients with Roux-en-Y gastrectomy.

OBJECTIVES: This study aimed to evaluate the efficacy and safety of stone extraction in patients who underwent Roux-en-Y gastrectomy using short-type single-balloon enteroscopy (SBE) and to clarify the factors affecting complete stone extraction in the initial procedure. METHODS: The data of patients with Roux-en-Y gastrectomy who underwent endoscopic stone extraction using short SBE between September 2011 and January 2022 was analyzed. RESULTS: Overall, 85 patients were scheduled to undergo stone extraction. 77 patients were intended stone extraction after successful biliary cannulation. The complete stone extraction success in the initial procedure, overall complete stone extraction success including repeated procedures, and adverse event rates were 68.2% (95% confidence interval [CI], 57.2%-77.9%), 87.1% (95% CI, 78.0%-93.4%), and 8.2% (95% CI, 3.4%-16.2%), respectively. Multiple logistic regression analysis indicated that bile duct diameter affected the success of complete stone extraction after successful biliary cannulation in the initial procedure (odds ratio 0.53, 95% CI, 0.30-0.94, p = .03). CONCLUSIONS: Stone extraction in patients with Roux-en-Y gastrectomy using short SBE was effective. Patients with a large diameter bile duct required several sessions for complete stone extraction, suggesting that more dedicated devices are warranted for patients with surgically altered anatomy.

Sivelestat's effect on Candida albicans water-soluble fraction-induced vasculitis.

BACKGROUND: We investigated the efficacy of sivelestat sodium hydrate (SSH) as a treatment for Kawasaki disease, and its pharmacological action sites, in mice with Candida albicans water-soluble fraction-induced vasculitis. METHODS: Sivelestat sodium hydrate was administered intraperitoneally to Candida albicans water-soluble fraction-induced vasculitis model mice to assess its efficacy in preventing the development of coronary artery lesions based on the degree of inflammatory cell infiltration in the aortic root and coronary arteries (vasculitis score). The pharmacological sites of action were investigated based on changes in neutrophil elastase (NE) and intercellular adhesion molecule 1 (ICAM-1) positive areas, ICAM-1 and tumor necrosis factor-α mRNA expression levels in the upper heart, and the proportion of monocytes in the peripheral blood. RESULTS: The vasculitis score decreased below the lower limit of the 95% confidence interval of untreated mice in 69% of the SSH-treated mice. The NE- and ICAM-1-positive regions, and the mRNA expression of ICAM-1 and tumor necrosis factor-α were lower in the SSH-treated mice than in the untreated mice. The proportion of monocytes in the peripheral blood was higher in the SSH-treated mice than in the untreated mice, whereas monocyte migration to inflammation areas was suppressed in the SSH-treated mice. CONCLUSIONS: Our results showed that SSH might prevent the development of coronary artery lesions and ameliorate disease activity. In addition to its NE-inhibitory effect, SSH sites of action may also include monocytes.

A retrospective cohort study of factors influencing long procedure times in colorectal endoscopic submucosal dissection.

OBJECTIVE: To evaluate the outcomes and factors influencing colorectal endoscopic submucosal dissection (ESD) with a long procedure time. MATERIALS AND METHODS: In this single-center, retrospective study, we included 1,100 patients with 1,199 lesions who underwent colorectal ESD between April 2016 and December 2020. ESD was performed using an advanced system knife for lesions >20 mm. An S-O clip was used as the traction device. The long-time group (LP; procedure time >120 min) and normal-time group (NP; procedure time <120 min) were compared. RESULTS: The procedure times were 166.86 and 44.72 min in the LP and NP groups, respectively. The completion rate was higher in the NP group (96.5% vs. 83.5%, p = .001); the completed lesions were resected en bloc. Multivariate analysis revealed 18.8% and 7.8% of submucosal fibrosis in the LP and NP groups, respectively (odds ratio [OR] = 2.410, p = .026). Compared to the NP group, the LP group presented larger maximum lesion sizes and higher rates of R1 resection, and traction device use. Time to introduction of traction device use was longer in the LP than in the NP group (126.05 vs. 21.72 min; p < .001). Fibrosis tends to occur cecal lesions (OR 2.436, p = .011) and laterally spreading tumor-non-granular-pseudo-depressed (LST-NG-PD) (OR 2.6181, p = .001). CONCLUSIONS: Lesion size and fibrosis were factors associated with a long procedure time in colonic ESD. For fibrotic lesions (LST-NG-PD and cecal lesions), it is necessary to consider early use of traction devices and advisable to plan a strategy for the use of traction devices.

FT-like proteins induce transposon silencing in the shoot apex during floral induction in rice.

Floral induction is a crucial developmental step in higher plants. Florigen, a mobile floral activator that is synthesized in the leaf and transported to the shoot apex, was recently identified as a protein encoded by FLOWERING LOCUS T (FT) and its orthologs; the rice florigen is Heading date 3a (Hd3a) protein. The 14-3-3 proteins mediate the interaction of Hd3a with the transcription factor OsFD1 to form a ternary structure called the florigen activation complex on the promoter of OsMADS15, a rice APETALA1 ortholog. However, crucial information, including the spatiotemporal overlap among FT-like proteins and the components of florigen activation complex and downstream genes, remains unclear. Here, we confirm that Hd3a coexists, in the same regions of the rice shoot apex, with the other components of the florigen activation complex and its transcriptional targets. Unexpectedly, however, RNA-sequencing analysis of shoot apex from wild-type and RNA-interference plants depleted of florigen activity revealed that 4,379 transposable elements (TEs; 58% of all classifiable rice TEs) were expressed collectively in the vegetative and reproductive shoot apex. Furthermore, in the reproductive shoot apex, 214 TEs were silenced by florigen. Our results suggest a link between floral induction and regulation of TEs.

The MET1b gene encoding a maintenance DNA methyltransferase is indispensable for normal development in rice.

While Arabidopsis bears only one MET1 gene encoding the DNA methyltransferase that is mainly responsible for maintaining CG methylation after DNA replication, rice carries two MET1 genes, MET1a and MET1b, expressed in actively replicating and dividing cells, and MET1b is more abundantly expressed than is MET1a. A met1a null mutant displayed no overt phenotypes, implying that MET1b must play a major role in the maintenance DNA methylation. Here, we employed two met1b null mutants, generated by homologous recombination-mediated knock-in targeting and insertion of endogenous retrotransposon Tos17. These MET1a/MET1a met1b/met1b homozygotes exhibited abnormal seed phenotypes, which is associated with either viviparous germination or early embryonic lethality. They also displayed decreased levels of DNA methylation at repetitive CentO sequences and at the FIE1 gene locus in the embryos. In addition, independently isolated knock-in-targeted plants, in which the promoterless GUS reporter gene was fused with the endogenous MET1b promoter, showed the reproducible, dosage-dependent, and spatiotemporal expression patterns of GUS. The genotyping analysis of selfed progeny of heterozygous met1a met1b null mutants indicated that weakly active MET1a seems to serve as a genetic backup mechanism in rice met1b gametophytes, although the stochastic and uncoordinated activation of epigenetic backup mechanisms occurred less efficiently in the met1b homozygotes of rice than in the met1 homozygotes of Arabidopsis. Moreover, passive depletion of CG methylation during the postmeiotic DNA replication in the haploid nuclei of the met1a met1b gametophytes in rice results in early embryonic lethality. This situation somewhat resembles that of the met1 gametophytes in Arabidopsis.

Usefulness and safety of new ultrasmall-diameter colonoscope for cases with difficult insertion: a retrospective study.

Colonoscopies are widely available, but there are cases where insertion can be difficult, even for experienced endoscopists. EC-760XP/L, a new ultrasmall-diameter long scope, may be useful in such cases. This single-center retrospective study included 39 cases where colonoscope insertion was difficult even when previously conducted by an experienced endoscopist. The primary outcome was the cecal intubation time using EC-760XP/L compared to the time used in a previous examination with a standard scope. The secondary outcomes were the cecum intubation rate, intestinal cleanliness level, adenoma detection rate, polyp detection rate, sedative use rate, occurrence of adverse events, and pain experience. A comparison of cecal intubation times between EC-760XP/L and the standard scope showed that insertion times were significantly lower with EC-760XP/L (9.5 min) compared to the standard scope (19 min) (p < 0.01). The standard scope achieved cecal intubation in 30 cases (76.9%), whereas EC-760XP/L reached the cecum in all cases (p < 0.01). Pain was observed in 3 cases (8.3%) with the EC-760XP/L, which was significantly lower than the 22 cases (56.4%) with the standard scope (p < 0.01). In conclusion, EC-760XP/L proved to be useful in cases where colonoscope insertion was difficult.

A null mutation of ROS1a for DNA demethylation in rice is not transmittable to progeny.

Genes that promote DNA methylation and demethylation in plants have been characterized mainly in Arabidopsis. Arabidopsis DNA demethylation is mediated by bi-functional DNA enzymes with glycosylase activity that removes 5-methylcytosine and lyase activity that nicks double-stranded DNA at an abasic site. Homologous recombination-promoted knock-in targeting of the ROS1a gene, the longest of six putative DNA demethylase genes in the rice genome, by fusing its endogenous promoter to the GUS reporter gene, led to reproducibly disrupted ROS1a in primary (T(0)) transgenic plants in the heterozygous condition. These T(0) plants exhibited no overt morphological phenotypes during the vegetative phase, and GUS staining showed ROS1a expression in pollen, unfertilized ovules and meristematic cells. Interestingly, neither the maternal nor paternal knock-in null allele, ros1a-GUS1, was virtually detected in the progeny; such an intransmittable null mutation is difficult to isolate by conventional mutagenesis techniques that are usually used to identify and isolate mutants in the progeny population. Even in the presence of the wild-type paternal ROS1a allele, the maternal ros1a-GUS1 allele caused failure of early-stage endosperm development, resulting in incomplete embryo development, with embryogenesis producing irregular but viable embryos that failed to complete seed dormancy, implying non-equivalent maternal and paternal contribution of ROS1a in endosperm development. The paternal ros1a-GUS1 allele was not transmitted to progeny, presumably because of a male gametophytic defect(s) prior to fertilization. Thus, ROS1a is indispensable in both male and female gametophytes, and DNA demethylation must plays important roles in both gametophytes.

Targeted disruption of an orthologue of DOMAINS REARRANGED METHYLASE 2, OsDRM2, impairs the growth of rice plants by abnormal DNA methylation.

Recent methylome analyses of the entire Arabidopsis thaliana genome using various mutants have provided detailed information about the DNA methylation pattern and its function. However, information about DNA methylation in other plants is limited, partly because of the lack of mutants. To study DNA methylation in rice (Oryza sativa) we applied homologous recombination-mediated gene targeting to generate targeted disruptants of OsDRM2, a rice orthologue of DOMAINS REARRANGED METHYLASE 1 and 2 (DRM1/2), which encode DNA methyltransferases responsible for de novo and non-CG methylation in Arabidopsis. Whereas Arabidopsis drm1 drm2 double mutants showed no morphological alterations, targeted disruptants of rice OsDRM2 displayed pleiotropic developmental phenotypes in both vegetative and reproductive stages, including growth defects, semi-dwarfed stature, reductions in tiller number, delayed heading or no heading, abnormal panicle and spikelet morphology, and complete sterility. In these osdrm2 disruptants, a 13.9% decrease in 5-methylcytosine was observed by HPLC analysis. The CG and non-CG methylation levels were reduced in RIRE7/CRR1 retrotransposons, and in 5S rDNA repeats. Associated transcriptional activation was detected in RIRE7/CRR1. Furthermore, de novo methylation by an RNA-directed DNA methylation (RdDM) process involving transgene-derived exogenous small interfering RNA (siRNA) was deficient in osdrm2-disrupted cells. Impaired growth and abnormal DNA methylation of osdrm2 disruptants were restored by the complementation of wild-type OsDRM2 cDNA. Our results suggest that OsDRM2 is responsible for de novo, CG and non-CG methylation in rice genomic sequences, and that DNA methylation regulated by OsDRM2 is essential for proper rice development in both vegetative and reproductive stages.

Gene editing a constitutively active OsRac1 by homologous recombination-based gene targeting induces immune responses in rice.

OsRac1 is a member of the plant small GTPase Rac/Rop family and plays a key role in rice immunity. The constitutively active (CA) G19V mutation of OsRac1 was previously shown to induce reactive oxygen species production, phytoalexin synthesis and defense gene activation, leading to resistance to rice blast infection. To study further the effect of the G19V mutation in disease resistance, we introduced a single base substitution by gene targeting and removed the selectable marker using Cre-loxP site-specific recombination. The CA-OsRac1 gene generated by gene targeting was termed CA-gOsRac1. The G19V mutation was transferred from a targeting vector to the OsRac1 locus and stably transmitted to the next generation. In the leaf blade of homozygous CA-gOsRac1 plants, mutant transcript levels were much lower than in those of wild-type plants. In contrast, mutant transcripts in roots, leaf sheaths and panicles were more abundant than those in leaf blades. However, upon chitin treatment, the expression of defense-related genes PAL1 and PBZ1 in the cell culture was greater in the mutants compared with wild-type plants. Furthermore, induction of hypersensitive response (HR)-like cell death was observed in the leaf sheaths of mutant plants infected with a compatible race of rice blast fungus. In the CA-gOsRac1 plants, a number of genes previously shown to be induced by Magnaporthe oryzae and Xanthomonas oryzae pv. oryzae (Xoo) infection were induced in the leaf sheath without pathogen infection. These results suggest that gene targeting will provide mutations useful for gene function studies and crop improvement.

Comparison of Fork-tip and Franseen needles for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions: A propensity-matched analysis.

Objectives: There is no unanimity regarding the most appropriate needle to use for an endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). To date, new types of FNB needles have been designed, including the Fork-tip and Franseen needles. This study primarily aimed to compare the diagnostic accuracy and histological quality between the use of the Franseen and Fork-tip needles in EUS-FNB for solid pancreatic lesions. Materials and methods: We retrospectively analyzed 147 patients at our center for solid pancreatic lesions, 75 of whom underwent EUS-FNB using a 22-G Franseen needle, and 72 using a 22-G Fork-tip needle, from December 2019 to September 2021. The present study conducted a propensity-matched analysis and confounder adjustment. Results: The diagnostic accuracy of the Fork-tip group (93.3%, 42/45) was the same as that of the Franseen group. For the core tissue and blood scores, no significant difference was observed (p = 0.58, 0.25) between the two groups. The rate of changes in the operator from that of a trainee to an expert was less in the Fork-tip group (4.4%, 2/45) than in the Franseen group (15.6%, 7/45), but not significantly different (p = 0.16). Conclusions: In both groups, the diagnostic accuracy and histological quality were not significantly different. Additionally, there were no significant differences in the rate of operator changes. As both needles are useful, the choice of using either of them is equally good.

Gel immersion endoscopic submucosal dissection: clinical experience with 13 cases of superficial esophageal cancer.

Esophageal endoscopic submucosal dissection (ESD) of tumors located on the gravity side is technically challenging. Given that gel immersion ESD (GIESD) is performed by immersing lesions in gel, we hypothesized that it could be used to eliminate the disadvantage associated with submerging the gravity side. Here, we performed GIESD using VISCOCLEAR for superficial esophageal cancer on the gravity side of the esophagus, with monopolar devices. This study aimed to evaluate the short-term outcomes of GIESD for superficial esophageal cancer. Fifteen patients with 16 superficial esophageal cancers underwent GIESD by a single operator, and 13 cases were evaluated. All patients were male, and GIESD was performed in the middle (12/13, 92.3 %) and lower (1/13, 7.7 %) thoracic esophagus. The lesions were located on the left (7/13, 53.8 %), posterior (5/13, 38.5 %), and right (1/13, 7.7 %) esophageal walls. The median procedure time was 27 minutes (interquartile range [IQR], 14-68), and the median dissection speed was 20 mm 2 /min (IQR, 14-25.7). The median amount of gel used was 400 mL (IQR, 360-580), and no gel-related adverse events were observed. The median total dose of midazolam was 3 mg (IQR, 2-5). GIESD was completed with en bloc and R0 resections achieved in 100 % of the 13 cases. Delayed adverse events, such as bleeding or perforation, did not occur (0/13, 0 %).

Effectiveness of a multi-loop traction device for colorectal endoscopic submucosal dissection performed by trainees: a pilot study.

Colorectal endoscopic submucosal dissection (ESD) is a difficult procedure, and its introduction to trainees has been debated. Although the criteria for performing colorectal ESD vary among institutions, it is often allowed after gaining experience performing surgeries in animals and upper gastrointestinal ESD. This pilot study aimed to compare the treatment outcomes of ESD performed by trainees using the multi-loop traction device (MLTD group) and those of conventional ESD performed by experts (control group). It also aimed to determine whether the MLTD can be used to safely introduce colorectal ESD to trainees. We included 26 colorectal ESD patients (13 in the MLTD group and 13 in the control group) treated at our hospital from October to December 2021. There were no significant differences in the procedure time (50 min vs. 30 min), dissection speed (19.9 mm2/min vs. 28.7 mm2/min), and intraoperative perforation (0% vs. 0%) of the two groups. Furthermore, the rate of ESD self-completion in the MLTD group was 100%. Therefore, the use of the MLTD allowed the safe introduction of colorectal ESD, even among endoscopists with no experience performing colorectal ESD. Consequently, the use of the MLTD may replace animal and upper gastrointestinal ESD when introducing colorectal ESD to trainees.