Effect of Two-Photon Excitation to 8-Azacoumarin Derivatives as Photolabile Protecting Groups.

An improvement of the two-photon excitation was achieved using 8-azacoumarin-type caged compounds, which showed large values of the two-photon uncaging action cross-section (δu >0.1 Goeppert-Mayer (GM)). In particular, the 7-hydroxy-6-iodo-8-azacoumarin (8-aza-Ihc)-caged compound showed an excellent uncaging action cross-section value (δu = 1.28 GM). Therefore, 8-azacoumarin-type photolabile protecting groups (PPGs) can be used as two-photon excitation sources.

Dissection and removal of bile duct plastic stents penetrating the duodenal papilla: report of three rare cases.

We encountered three cases with incidental penetration of a straight Amsterdam-type bile duct plastic stent into the duodenal papilla. All patients had undergone insertion of a biliary plastic stent due to common bile duct stones. However, in all three cases, we observed penetration of the biliary plastic stent into the duodenal papilla just before the elective surgery or at the time of plastic stent replacement. We, therefore, performed stent dissection using a bipolar snare and were able to safely remove the plastic stents in all three cases. We believe that this is the first report of plastic stent dissection using a bipolar snare.

MAFK Polymorphisms Located in 3'-UTR are Associated with Severity of Atrophy and CDKN2A Methylation Status in the Gastric Mucosa.

Objective: This study aimed to clarify the association of MAFK polymorphisms (rs4268033, rs3735656, and rs10226620) with the degree of gastric mucosal atrophy and CDKN2A CpG methylation status. Methods: A total of 491 subjects were enrolled in this study. Genotypes and methylation status were determined by polymerase chain reaction (PCR)-single-stranded conformation polymorphism and methylation-specific PCR (Fujita Health University, HM18-094). Methods: A total of 491 subjects were enrolled in this study. Genotypes and methylation status were determined by polymerase chain reaction (PCR)-single-stranded conformation polymorphism and methylation-specific PCR (Fujita Health University, HM18-094). Results: Either rs3735656 or rs10226620, located in the 3'-UTR of MAFK, was significantly associated with the severity of gastric mucosal atrophy using a dominant genetic model (odds ratio [OR], 2.10; p = 0.0012, and OR, 1.98; p = 0.0027, respectively). However, using a recessive genetic model, no significant association was found between three polymorphisms and gastric mucosal atrophy. The serum pepsinogen I/II ratio was significantly lower in subjects with minor alleles of rs3735656 and rs10226620 than in subjects with the wild homozygous allele (p = 0.018 and 0.013, respectively). In a subgroup including 400 of the 491 subjects, the CpG of p14ARF and p16 INK4a were methylated in 132 and 112 subjects, respectively. Fifty subjects had both CpG methylations and 206 subjects had neither methylation. When comparing the groups with both and neither methylations, there were no significant associations between three polymorphisms and CDKN2A methylation using a dominant genetic model. However, all polymorphisms investigated in this study (rs4268033, rs3735656, and rs10226620) were significantly associated with CDKN2A methylation in a recessive genetic model (OR, 3.58; p = 0.0071, OR, 4.49; p = 0.0004, and OR, 3.45; p = 0.0027, respectively). Conclusions: Our results indicate that carrying the minor allele of the MAFK polymorphisms, particularly when they are located in the 3'-UTR, has a high risk for the severity of gastric mucosal atrophy; furthermore, CDKN2A CpG methylation may develop in subjects with homozygous minor allele of these polymorphisms.

Effect of DNMT3A polymorphisms on CpG island hypermethylation in gastric mucosa.

BACKGROUND: CpG methylation of tumor suppressor genes occurs in the early stage of carcinogenesis. Detecting risk factors for aberrant CpG methylation is clinically important for predicting cancer development. DNA methyltransferase (DNMT) 3a is considered to play critical roles in the DNA methylation process during pathogenesis. In this study, we evaluated the association between DNMT3A polymorphisms (rs6733868 and rs13428812) and CpG methylation status in non-cancerous gastric mucosa. METHODS: We determined the DNMT3A genotype and CpG methylation status of 4 genes (p14ARF, p16INK4a, DAPK, and CDH1) in 510 subjects without gastric cancer. Helicobacter pylori (HP) infection status was determined by the rapid urease test, urea breath test, speculum examination, or serum antibody test. We determined the DNMT3A genotype using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP). CpG methylation status was determined by methylation-specific polymerase chain reaction (MSP). When the methylated band was stronger than 10 ng/µL according to the DNA marker, we judged CpG island hypermethylation (CIHM) to be present. Associations between genotypes and susceptibilities were assessed by logistic regression analysis. RESULTS: The minor allele frequencies of both polymorphisms (rs6733868 and rs13428812) were lower in the CpG methylated groups of each of the 4 genes (p14ARF, p16INK4a, DAPK, and CDH1). Using a dominant genetic model, rs6733868 was significantly associated with the hypermethylation of each gene, whereas rs13428812 was associated with the methylation of 3 genes (all except p14ARF). When low-CIHM was defined as 1 or 2 CpG islands methylated and high-CIHM was defined as 3 or more CpG islands methylated, carrying the minor allele of rs6733868 was associated with both decreased low- and high-CIHM, and that of rs13428812 also was associated with a decrease. Comparing low-CIHM with high-CIHM, carrying the minor alleles of rs6733868 or rs13428812 was related to decreased susceptibility to high-CIHM. In HP-infected subjects, carrying the minor alleles of rs6733868 or rs13428812 had a significantly greater association with decreased susceptibility to high-CIHM. CONCLUSIONS: Our study indicates that polymorphisms of DNMT3A are associated with the accumulation of gene methylation in gastric mucosa. Carrying the minor alleles of rs6733868 or rs13428812 inhibits aberrant gene methylations, which are typically enhanced by HP infection.

Influence of MIF polymorphisms on CpG island hyper-methylation of CDKN2A in the patients with ulcerative colitis.

BACKGROUND: CDKN2A hypermethylation is among the major events associated with carcinogenesis and is also observed in non-neoplastic colonic mucosa in patients with ulcerative colitis (UC). Macrophage migration inhibitory factor (MIF) plays a crucial role in promoting gastrointestinal inflammation characteristic of UC. The aim of this study is to explore associations between CDKN2A methylation status and MIF polymorphisms (rs755622 and rs5844572). METHODS: One hundred and fifty-nine patients diagnosed with UC were enrolled in this study. The methylation status of p14ARF and p16INK4a was determined by MSP; MIF genotypes were identified by PCR-SSCP. RESULTS: We found no differences with respect to mean age, gender, clinical type (chronic continuous or relapse/remitting), or extent of disease among the patients with methylated and unmethylated p14ARF or p16INK4a. Carrying the rs755622 C allele indicated a significantly higher risk for p14ARF methylation (odds ratio (OR), 2.16; 95% confidence interval (CI), 1.08-4.32; p = 0.030); similarly, carrying the rs5844572 7-repeat allele indicated a significantly higher risk for p16INK4a methylation (OR, 2.57; 95% CI, 1.26-5.24; p = 0.0094) after an adjusted regression analysis. The carriers of the rs755662 C allele or the rs5844572 7-repeat allele were both at a significantly higher risk for methylation of both p14ARF and p16INK4a when compared to the cohort in which neither of the genes were methylated (OR, 2.70; 95% CI, 1.22-6.01; p = 0.015 and OR, 2.87; 95% CI, 1.25-6.62; p = 0.013, respectively). Additionally, carrying rs755622 C allele was significantly associated with CIHM in chronic continuous of clinical type and total colitis (OR, 25.9; 95% CI, 2.55-262.6; p = 0.0059 and OR, 4.38; 95% CI, 1.12-17.2; p = 0.034, respectively), and carrying 7-repeat allele of rs5844572 was significantly associated in chronic continuous type (OR, 14.5; 95%CI, 1.46-144.3; p = 0.022). CONCLUSIONS: Taken together, our findings suggest that MIF genotypes associated with inflammation may also be involved in promoting carcinogenesis via CDKN2A hypermethylation in patients diagnosed with UC.

Durvalumab-induced Immune-related Hepatitis in a Patient with Non-small Cell Lung Cancer.

We herein report the case of a 79-year-old patient with unresectable stage III non-small cell lung cancer who developed immune-related hepatitis caused by durvalumab administration. Durvalumab was administered at 10 mg/kg every two weeks after the treatment with carboplatin (AUC2), paclitaxel (35 mg/m2), and 60 Gy radiation. At the day 208 in which the 14th durvalumab administration was scheduled, the patient was urgently hospitalized due to CTCAE Grade 4 hepatic dysfunction detected during the an outpatient blood sampling test. He was diagnosed with immune-related hepatitis and started on methylprednisolone 60 mg/day. After 51 days, his liver dysfunction improved and he was discharged.

Synthesis of hydrophilic caged DAG-lactones for chemical biology applications.

The 6-bromo-7-hydroxy-coumarin-4-ylmethyl (Bhc) group has been used widely in cage chemistry because of its high molar absorptivity and photolytic efficiency. One of the drawbacks of coumarins however is their low aqueous solubility. Aqueous solubility is important in the behavior of caged compounds because hydrophobic caged compounds might be aggregated in physiological conditions and consequently the photocleavage would be impaired. The 8-azacoumarin-4-ylmethyl derivatives with bromine (8-aza-Bhc) or iodine (8-aza-Ihc), which were previously developed in this laboratory, have aqueous solubilities that are higher than those of related coumarins. Here, to improve the hydrophilicity and management of caged diacylglycerol lactones (DAG-lactones), 8-aza-Bhc and 8-aza-Ihc were introduced into the DAG-lactone structure. The synthesized caged compounds showed high hydrophilicity compared with the parent Bhc-caged DAG-lactone, and the 8-aza-Ihc-caged DAG-lactone (2) showed excellent photolytic efficiency, which allows rapid release of the DAG-lactone (1) by brief photoirradiation. The 8-aza-7-hydroxy-6-iodo-coumarin-4-ylmethyl group might be useful for caging of bioactive compounds, especially hydrophobic compounds.

[Intestinal amebiasis in the ileac blind end of an ileocolonic anastomosis leading to liver abscess].

A 65-year-old man was admitted complaining of high fever and pain in the right lower abdomen. An ileocolonic side-to-end anastomosis had been performed 38 years previously for an abscess in a colonic diverticulum. On the current admission, findings on contrast-enhanced computed tomography suggested an amebic liver abscess and intestinal amebiasis. Colonoscopy revealed an irregularly shaped ulcer and false membrane in the ileal blind end of the ileocolonic anastomosis. Amebic trophozoites were seen by rapid microscopy. Amebiasis in the blind end of the ileum has rarely been reported. This case is of particular interest because the intestinal amebiasis also led to a liver abscess.

Association of genetic polymorphisms in DNMT3A with the progression of gastric mucosal atrophy and susceptibility to gastric cancer in Japan.

The aim of the present study was to investigate whether single nucleotide polymorphisms in the DNMT3A gene are associated with susceptibility to gastric cancer in the Japanese population. The present case-control study examined the associations between single nucleotide polymorphisms (rs6733868 and rs13428812) in DNMT3A and cancer susceptibility in 343 patients with gastric cancer and 708 subjects without gastric malignancies on upper gastro-duodenal endoscopy. Of 708 controls, 409 were classified into two groups histologically: 99 cases with and 310 cases without gastric mucosal atrophy. Overall, homozygosity for the DNMT3A rs6733868 minor allele was significantly associated with a reduced risk of gastric cancer (odds ratio [OR], 0.621; 95% confidence interval [CI], 0.402-0.958; P=0.031), especially of the intestinal type (OR, 0.494; 95% CI, 0.274-0.890; P=0.019). In subjects >60 years, rs6733868 minor allele homozygosity was significantly associated with gastric cancer susceptibility. Carriers of the rs6733868 minor allele had a reduced risk of severe gastric mucosal atrophy (OR, 0.495; 95% CI, 0.299-0.826; P=0.0069). In addition, the number of minor alleles of both rs6733868 and rs13428812 was significantly correlated with the risk of Helicobacter pylori (HP) infection (P=0.0070 and P=0.0050, respectively). However, rs13428812 was not associated with severe gastric mucosal atrophy or gastric carcinogenesis. The present results suggest that DNMT3A polymorphisms serve roles in the progression from HP infection to gastric mucosal atrophy and gastric carcinogenesis in terms of degree and manner.

Genetic polymorphisms of MAFK, encoding a small Maf protein, are associated with susceptibility to ulcerative colitis in Japan.

AIM: To investigate whether single nucleotide polymorphisms in maf protein K (MAFK), which encodes the MAFK, lead to increased susceptibility to ulcerative colitis in the Japanese population. METHODS: This case control study examined the associations between MAFK single nucleotide polymorphisms (rs4268033 G>A, rs3735656 T>C and rs10226620 C>T) and ulcerative colitis susceptibility in 174 patients with ulcerative colitis (UC) cases, and 748 subjects without no lower abdominal symptoms, diarrhea or hematochezia (controls). In addition, as the second controls, we set 360 subjects, who have an irregular bowel movement without abnormal lower endoscopic findings (IBM controls). RESULTS: The genotype frequency of rs4268033 AA and allelic frequency of the rs4268033A allele were significantly higher in the UC cases than in both controls (P = 0.0005 and < 0.0001, P = 0.015 and 0.0027 vs controls and IBM controls, respectively). Logistic regression analysis after adjustment for age and gender showed that the rs4268033 AA and rs3735656 CC genotypes were significantly associated with susceptibility to UC development (OR = 2.63, 95%CI: 1.61-4.30, P = 0.0001 and OR = 1.81; 95%CI: 1.12-2.94, P = 0.015, respectively). Similar findings were observed by the comparison with IBM controls. In addition, the rs4268033 AA genotype was significantly associated with all phenotypes of UC except early onset. There was no significant association between rs10226620 and ulcerative colitis. CONCLUSION: Our results provide the first evidence that MAFK genetic polymorphisms are significantly associated with susceptibility to UC development. In particular, rs4268033 is closely associated with an increased risk for the development of UC.

Microwave-Assisted Synthesis of Azacoumarin Fluorophores and the Fluorescence Characterization.

By screening of reaction conditions and evaluation of its fluorescent properties, an environmentally sensitive fluorescent group, 8-aza-7-hydroxy-4-methylcoumarin, was synthesized in 70% yield using MgBr2 as a Lewis acid under microwave irradiation. It has a high fluorescent quantum yield, is adequately soluble in water, and produces fluorescent emission in protic solvents and at neutral pH. Therefore, it could be useful in biosensors that are required to emit in hydrophilic environments such as cells.

Utilization of the Heavy Atom Effect for the Development of a Photosensitive 8-Azacoumarin-Type Photolabile Protecting Group.

A remarkable improvement of the photochemical properties of coumarin-type photolabile protecting groups was achieved by iodine substitution. The newly identified 7-hydroxy-6-iodo-8-azacoumarin (8-aza-Ihc)-caged acetate showed excellent photolytic efficiency, significantly higher than that of the corresponding bromine-containing coumarin- and azacoumarin-type caging groups. The results provide a solid approach to improving the photosensitivity of photolabile protecting groups.

Isostere-based design of 8-azacoumarin-type photolabile protecting groups: a hydrophilicity-increasing strategy for coumarin-4-ylmethyls.

Described is the development of 8-azacoumarin-4-ylmethyl groups as aqueous photolabile protecting groups. A key feature of the strategy is the isosteric replacement of the C7-C8 enol double bond of the Bhc derivative with an amide bond, resulting in conversion of the chromophore from coumarin to 8-azacoumarin. This strategy makes dramatically enhanced water solubility and facile photocleavage possible.

Low-molecular-weight CXCR4 ligands with variable spacers.

Low-molecular-weight CXCR4 ligands based on known lead compounds including the 14-mer peptide T140, the cyclic pentapeptide FC131, peptide mimetics, and dipicolylamine-containing compounds were designed and synthesized. Three types of aromatic spacers, 1,4-phenylenedimethanamine, naphthalene-2,6-diyldimethanamine, and [1,1'-biphenyl]-4,4'-diyldimethanamine, were used to build four pharmacophore groups. As pharmacophore groups, 2-pyridylmethyl and 1-naphthylmethyl are present in all of the compounds, and several aromatic groups and a cationic group from 1-propylguanidine and 1,1,3,3-tetramethyl-2-propylguanidine were also used. Several compounds showed significant CXCR4 binding affinity, and zinc(II) complexation of bis(pyridin-2-ylmethyl)amine moieties resulted in a remarkable increase in CXCR4 binding affinity.