Species-dependent patterns of incorporation of purine mononucleotides and nucleosides by lactic acid bacteria

Although most lactic acid bacteria do not directly incorporate purine nucleotides, the strain Lactobacillus gasseri PA-3 was found to incorporate purine mononucleotides. To determine whether the direct uptake of purine mononucleotides is dependent on the species or strain of lactic acid bacteria, incorporation of purine mononucleotides was assessed in L. gasseri, Lactcoccus lactis sbsp. lactis, Streptococcus thermophilus and other species of lactic acid bacteria. Each bacterial strain was incubated with ³²P-AMP or ¹⁴C-adenosine and the incorporation of each purine was evaluated by measuring their radioactivity. All investigated strains of L. gasseri incorporated ³²P-AMP, whereas strains of S. thermophilus and most strains of L. lactis did not. Incorporation of ³²P-AMP into strains of Pediococcus was dependent on the strain or species of that genus of bacteria. All investigated strains, except for one strain of L. gasseri, incorporated ¹⁴C-adenosine, with S. thermophilus, L. lactis and Pediococcus generally displaying greater incorporation of ¹⁴C-adenosine than L. gasseri. Although most lactic acid bacteria such as S. thermophiles and L. lactis do not incorporate purine mononucleotides, some species such as L. gasseri directly incorporate purine mononucleotides. These findings indicate that the preferential incorporation of purine mononucleotides or nucleosides by lactic acid bacteria is dependent on the species or strain.

Control system for the new RIKEN 28-GHz superconducting electron cyclotron resonance ion source for SRILAC

A new RIKEN 28-GHz superconducting electron cyclotron resonance ion source (SC-ECRIS) has been installed for the superconducting RIKEN linear accelerator (SRILAC). The new SC-ECRIS control system mainly consists of programmable logic controllers (PLCs) embedded with the Experimental Physics and Industrial Control System. To improve the reliability as compared with previous control systems, two types of PLC central processing units, sequential and Linux, have been installed in the same unit. Past experience has shown that new types of designs that can rapidly respond to system scalability are key. By connecting PLC stations using star-topology field buses, their rapid and cost-effective response to system changes is realized for the new devices. Furthermore, a unique data acquisition system employing a 920-MHz-band radio was developed to measure analog data such as the temperature at the high-voltage stage.

Treatment of finger phalangeal fractures using the Ichi-Fixator system: A prospective study of 12 cases

External fixators are an effective treatment option for comminuted or unstable phalangeal fractures. We developed a new linked-wire type of external fixator (the Ichi-Fixator) for finger phalangeal fractures, which enables fine adjustment of the fixation under fluoroscopy guidance either in a static way or with distraction through small screws inside the fixator. This technique was designed to improve on the stability and rigidity of conventional percutaneous Kirchner wire fixation. We assessed the effectiveness of the fixator through 12 cases of open or percutaneous fixation in comminuted or unstable phalangeal fractures. All patients were examined for postoperative complications, functional recovery, pain on visual analog scale (VAS), and the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score at the final follow-up visit. Patients could perform all routine activities with normal grip strength and a full range of hand motion without pain after treatment. This treatment, which reduces the postoperative discomfort and may allow an immediate return to work, will clearly boost patient satisfaction. Linked-wire type external fixation enhances the security of fixation, facilitates postoperative mobilization, and may allow an immediate return to work.

Complications and outcomes in diffuse large B-cell lymphoma with gastric lesions treated with R-CHOP

Standard therapy for gastric diffuse large B‐cell lymphoma (DLBCL) is considered to be chemotherapy with or without involved‐field radiation therapy. Although R‐CHOP therapy alone is widely used for DLBCL with gastric lesions (DLBCL‐GL), the outcome and incidence of treatment‐related gastric complications following R‐CHOP are not well known. This study aimed to evaluate the outcome after R‐CHOP therapy in patients with gastric DLBCL including gastric complications and to identify risk factors for the complications. Consecutive patients with newly diagnosed DLBCL‐GL treated with R‐CHOP between 2003 and 2014 were retrospectively evaluated. DLBCL‐GL was defined only when pathologically confirmed in the stomach. Of the 96 patients with DLBCL‐GL, 63 patients were diagnosed with gastric symptoms. Eighty‐eight patients (92%) completed six to eight cycles of R‐CHOP. The complete remission (CR) rate was 86%, and 3‐year and 5‐year overall survival rates were 80% and 73%, respectively. Patients were well stratified according to the Revised International Prognostic Index (R‐IPI). Complication rate was 8% (8/96); seven patients had bleeding and three had stenosis. No patients had gastric perforation. Bleeding occurred during the first cycle of R‐CHOP in five patients (5/7, 71%). Patients with gastric complications had a lower R‐CHOP completion rate (50%, P = 0.001) and a lower CR rate (25%, P < 0.001) than those without complications. A low serum albumin level at diagnosis was the only risk factor identified for gastric complications (P = 0.001) and six of the eight patients with complications were shown to be at stage IV. Further studies of DLBCL‐GL are warranted to identify patients at high risk for gastric complications and to provide better treatment strategies.

Mechanism for Decreased Gene Expression of β4-Galactosyltransferase 5 upon Differentiation of 3T3-L1 Mouse Preadipocytes to Adipocytes

Upon differentiation of cells, remarkable changes in the structures of glycans linked to lipids on cell surface have been observed. Lactosylceramide (Lac-Cer) serves as a common precursor for a series of glycosphingolipids with diverse structures. In the present study, we examined the underlying mechanism for the biosynthesis of Lac-Cer upon differentiation of 3T3-L1 mouse preadipocytes to adipocytes. TLC analysis showed that the amounts of Lac-Cer decrease in 3T3-L1 adipocytes compared to 3T3-L1 preadipocytes. In accordance with this change, the gene expression level of β4-galactosyltransferase (β4GalT) 5, which was identified as Lac-Cer synthase, decreased drastically upon differentiation of 3T3-L1 preadipocytes. The analysis of the transcriptional mechanism of the β4GalT5 gene demonstrated that the core promoter region is identified between nucleotides -299 and -1 relative to the translational start site. During adipocyte differentiation, the expression levels and promoter activities of the β4GalT5 gene decreased dramatically. Since the Specificity protein 1 (Sp1)-binding sites in the promoter region were critical for the promoter activity, it is suggested that Sp1 plays an important role for the expression of the β4GalT5 gene in 3T3-L1 cells. The gene and protein expression of Sp1 decreased significantly upon differentiation of 3T3-L1 preadipocytes. Taken together, the present study suggest that the expression of the β4GalT5 gene decreases through reduced expression of the Sp1 gene and protein upon differentiation of 3T3-L1 peradipocytes to adipocytes, which may lead to the decreased amounts of Lac-Cer in 3T3-L1 adipocytes.

The observed variation in the purine composition of food after soaking in sake lees

In this study, we investigated the alterations in the purine composition of swordfish prepared using a traditional Japanese processing method of soaking in sake lees. These alterations are the byproducts of the yeast fermentation of rice-koji and are renowned for enhancing the umami nature of food. Using a conventional assay method for hydrolyzing all of the purines into four bases and our developed method for simultaneously analyzing purines, we observed the alterations in four purine bases in the soaked sake lees and swordfish. The findings showed that the total purine content, and hypoxanthine-related and guanine-related purines in swordfish decreased after soaking in sake lees. We also analyzed the free purine composition and showed that the ratio of IMP in swordfish was decreased by soaking, while that of inosine in sake lees was increased by soaking swordfish in it.

Simultaneous quantification by HPLC of purines in umami soup stock and evaluation of their effects on extracellular and intracellular purine metabolism

Ribonucleotide flavor enhancers such as inosine monophosphate (IMP) and guanosine monophosphate (GMP) provide umami taste, similarly to glutamine. Japanese cuisine frequently uses soup stocks containing these nucleotides to enhance umami. We quantified 18 types of purines (nucleotides, nucleosides, and purine bases) in three soup stocks (chicken, consommé, and dried bonito soup). IMP was the most abundant purine in all umami soup stocks, followed by hypoxanthine, inosine, and GMP. The IMP content of dried bonito soup was the highest of the three soup stocks. We also evaluated the effects of these purines on extracellular and intracellular purine metabolism in HepG2 cells after adding each umami soup stock to the cells. An increase in inosine and hypoxanthine was evident 1 h and 4 h after soup stock addition, and a low amount of xanthine and guanosine was observed in the extracellular medium. The addition of chicken soup stock resulted in increased intracellular and extracellular levels of uric acid and guanosine. Purine metabolism may be affected by ingredients present in soups.

The different pathogeneses of sporadic adenoma and adenocarcinoma in non-ampullary lesions of the proximal and distal duodenum

Non-ampullary duodenal adenoma with activation of Wnt/β-catenin signalling is common in familial adenomatous polyposis (FAP) patients, whereas sporadic non-ampullary adenoma is uncommon. The adenoma-carcinoma sequence similar to colon cancer is associated with duodenal tumors in FAP, but not always in sporadic tumors. We obtained 37 non-ampullary duodenal tumors, including 25 adenomas and 12 adenocarcinomas, were obtained from biopsies and endoscopic resections. We performed immunohistochemistry for β-catenin, the hallmark of Wnt activation, and aldehyde dehydrogenase 1 (ALDH1), a putative cancer stem cell marker. In non-ampullary lesions, abnormal nuclear localization of β-catenin was observed in 21 (84.0%) of 25 adenomas and 4 (33.3%) of 12 adenocarcinomas. In the proximal duodenum, nuclear β-catenin was less frequent in both adenomas and adenocarcinomas. Gastric duodenal metaplasia (GDM) was observed only in the proximal duodenum. All adenomas with GDM were the gastric foveolar and pyloric gland types, and showed only membranous β-catenin. The intestinal-type adenomas had nuclear β-catenin in the proximal and distal duodenum. ALDH1-positive cells were more frequent in adenocarcinomas than adenomas. Nuclear β-catenin accumulation frequently occurred in ALDH1-positive cells in adenoma, but not in adenocarcinoma. In the non-ampullary proximal duodenum, Wnt/β-catenin pathway activation was more closely associated with adenomas than adenocarcinomas, and while it might cooperate with ALDH1 in adenoma, it does not in adenocarcinoma. The pathogenesis thus may differ between sporadic adenoma and adenocarcinoma of non-ampullary duodenal lesions, especially in the proximal and distal duodenum.

Abstract P3-13-06: Tailored neoadjuvant endocrine and chemo-endocrine therapy for postmenopausal patients with estrogen receptor-positive human epidermal growth factor receptor 2-negative primary breast cancer

Aims We investigated the efficacy and safety of initial neoadjuvant endocrine therapy with exemestane (EXE) alone followed by subsequent tailored treatment with EXE alone for responders or EXE plus oral metronomic cyclophosphamide (CPA) for non-responders.

Methods In this multicenter open-label phase II study, we enrolled postmenopausal patients with primary invasive estrogen receptor (ER)-positive, HER2-negative, stage I–IIIA (T1c–T3 N0–2 M0) breast cancer and Ki67 index ≤ 30%. Patients first received EXE 25mg/day for 12 weeks. Based on clinical response and change in Ki67 index in response to the initial therapy, patients who achieved complete response (CR), partial response (PR) with Ki67 index ≤5% after treatment, or stable disease (SD) with Ki67 index ≤5% both before and after treatment were defined as responders. Non-responders were defined as patients with PR and Ki67 index &gt;5% after treatment, or SD and Ki67 index &gt;5% before or after treatment. For the subsequent 24 weeks, responders continued the EXE monotherapy (continued EXE group), whereas non-responders switched to combination therapy with EXE plus CPA 50mg/day (EXE+CPA group). The primary endpoint was clinical response (CR and PR) at weeks 24 and 36.

Results A total of 59 patients (median age 69 years, range 53–86 years) were enrolled between January 2011 and July 2015. After exclusion of 3 (2 with progressive disease, 1 with an adverse event, AE) who discontinued treatment in the initial 12-week EXE monotherapy period, 56 remained enrolled to receive subsequent treatment. After 8–12 weeks of the initial EXE monotherapy, 14 patients were classified as responders (9 with PR and Ki67 index ≤5% after treatment; 5 with SD and Ki67 index ≤5% before and after treatment), whereas 42 were classified as non-responders (3 with PR and Ki67 index &gt;5% after treatment; 39 with SD and Ki67 index &gt;5% before or after treatment). Clinical response rates at weeks 24 and 36 were 85% (12/14, 95%CI 57.2–98.2%) and 76% (10/13, 95%CI 46.2–95.0%), respectively, in the continued EXE group, and 56% (23/41, 95%CI 39.7–71.5%) and 76% (30/39, 95%CI 60.7–88.9%), respectively, in the EXE+CPA group. At week 36, no significant difference was found in median Ki67 index between the continued EXE and EXE+CPA groups (3.5% and 4.0%, respectively). The proportion of patients with preoperative endocrine prognostic index (PEPI) 0 was also similar between the continued EXE and EXE+CPA groups (21.4% and 23.8%, respectively). The breast-conserving surgery rate was 71.4% and 69.0%, respectively. Grade 3 AEs were elevated liver enzymes (1 patient) in the continued EXE group, and gastritis, hypertriglyceridemia, and bone mineral density loss (1 patient each) in the EXE+CPA group.

Conclusion Switching from EXE monotherapy to EXE+CPA combination therapy based on clinical response and biological response (change in Ki67 index) to initial therapy improved subsequent clinical response in non-responders. Favorable clinical response to EXE alone was maintained in responders. Tailored neoadjuvant endocrine and chemo-endocrine therapy was shown to be effective in postmenopausal ER-positive breast cancer patients. (JBCRG-11CPA; UMIN000004751)

Citation Format: Masuda N, Sato N, Morimoto T, Ueno T, Kanbayashi C, Kaneko K, Yasojima H, Saji S, Sasano H, Morita S, Ohno S, Toi M. Tailored neoadjuvant endocrine and chemo-endocrine therapy for postmenopausal patients with estrogen receptor-positive human epidermal growth factor receptor 2-negative primary breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-13-06.

Multiple convex demarcation line for prediction of benign depressed gastric lesions in magnifying narrow-band imaging

BACKGROUND AND STUDY AIMS

 With magnifying narrow-band imaging (M-NBI) of the gastric mucosa, a characteristic demarcation line (DL) is occasionally found in non-cancerous depressed lesions. This DL forms multiple convex shapes along the edge of the epithelia of surrounding mucosa. We have termed this novel finding a multiple convex DL (MCDL). In this study, we clarified the prevalence of an MCDL in depressed gastric lesions detected in patients at high risk for gastric cancer and determined the diagnostic yield necessary to distinguish between cancer and non-cancer.

PATIENTS AND METHODS

 This was a post hoc analysis of a multicenter prospective trial. In total, 362 small (≤ 10 mm) depressed lesions were detected in 1353 patients. Presence or absence of a DL in target lesions was evaluated on M-NBI images. The proportion of MCDLs among lesions with a DL was evaluated.

RESULTS

Images of 347 lesions (39 cancerous and 308 non-cancerous) were evaluable. A DL was present in 252/347 lesions (73 %). When the cutoff value for the proportion of MCDLs needed to distinguish non-cancer from cancer was set at two-thirds, an MCDL was observed in 86/252 lesions (34 %). In 86 lesions with an MCDL, 83 (97 %) were non-cancerous. The sensitivity, specificity, positive predictive value, and negative predictive value of an MCDL for non-cancerous lesions were 38 %, 91 %, 97 %, and 19 %, respectively.

CONCLUSIONS

 Presence of an MCDL had high specificity and positive predictive value for non-cancerous lesions. Evaluating the shape of the DL is useful for differentiation between cancer and non-cancerous lesions.

A non-randomized confirmatory trial of an expanded indication for endoscopic submucosal dissection for intestinal-type gastric cancer (cT1a): the Japan Clinical Oncology Group study (JCOG0607)

BACKGROUND

Endoscopic resection has been limited to intestinal-type gastric cancer (cT1a) with a low risk of lymph node metastasis (T1a ≤2 cm, without ulcers). This single-arm confirmatory trial evaluated the efficacy and safety of endoscopic submucosal dissection (ESD) for >2 cm ulcer-negative and ≤3 cm ulcer-positive intestinal-type gastric cancer (cT1a).

METHODS

The eligibility criteria included endoscopically diagnosed cT1a, a single primary intestinal-type gastric adenocarcinoma, an ulcer-negative lesion of any size or a ≤3 cm ulcer-positive lesion, cN0M0, and no prior treatment. If ESD resulted in noncurative resection, surgical resection was added. The primary endpoint was the 5-year overall survival (OS) (planned sample size was 470, with a one-sided alpha level of 2.5%). The threshold 5-year OS was 86.1%.

RESULTS

We enrolled 470 early gastric cancer patients [median tumor size, 25 (5-130) mm] from 29 institutions between June 2007 and October 2010. These patients had 152 ulcer-negative lesions (>2 and ≤3 cm), 111 ulcer-negative lesions (>3 cm), and 207 ulcer-positive lesions (≤3 cm). The success rate for en block resection was 99.1% (466/470). Additional gastrectomy was conducted in 131 patients (28%) who did not fulfill the curative resection criteria. The 5-year OS of all patients was 97.0% (95% confidence interval, 95.0-98.2%), which was higher than the threshold 5-year OS (86.1%). The 317 patients who satisfied the curative resection criteria had no recurrence. There were no ESD-related grade 4 adverse events.

CONCLUSION

ESD for early gastric cancers that met the expanded criteria for intestinal-type gastric cancer (cT1a) was acceptable and should be the standard treatment instead of gastrectomy.

Conceptualizing the origin of life in terms of evolution

In this opinion piece, we discuss how to place evolution in the context of origin-of-life research. Our discussion starts with a popular definition: 'life is a self-sustained chemical system capable of undergoing Darwinian evolution'. According to this definition, the origin of life is the same as the origin of evolution: evolution is the 'end' of the origin of life. This perspective, however, has a limitation, in that the ability of evolution in and of itself is insufficient to explain the origin of life as we know it, as indicated by Spiegelman's and Lincoln and Joyce's experiments. This limitation provokes a crucial question: What conditions are required for replicating systems to evolve into life? From this perspective, the origin of life includes the emergence of life through evolution: evolution is a 'means' of the origin of life. After reviewing Eigen's pioneering work on this question, we mention our ongoing work suggesting that a key condition might be conflicting multi-level evolution. Taken together, there are thus two questions regarding the origin of life: how evolution gets started, and how evolution produces life. Evolution is, therefore, at the centre of the origin of life, where the two lines of enquiry must meet.This article is part of the themed issue 'Reconceptualizing the origins of life'.

8-Nitro-cGMP is a promoter of osteoclast differentiation induced by RANKL

Osteoclasts are multinucleated giant cells differentiated from monocyte-macrophage-lineage cells under stimulation of receptor activator of nuclear factor κ-B (RANK) ligand (RANKL) produced by osteoblasts and osteocytes. Although it has been reported that nitric oxide (NO) and reactive oxygen species (ROS) are involved in this process, the mechanism by which these labile molecules promote osteoclast differentiation are not fully understood. In this study, we investigated the formation and function of 8-nitro-cGMP, a downstream molecule of NO and ROS, in the process of osteoclast differentiation in vitro. 8-Nitro-cGMP was detected in mouse bone marrow macrophages and osteoclasts differentiated from macrophages in the presence of RANKL. Inhibition of NO synthase suppressed the formation of 8-nitro-cGMP as well as RANKL-induced osteoclast differentiation from macrophages. On the other hand, RANKL-induced osteoclast differentiation was promoted by addition of 8-nitro-cGMP to the cultures. In addition, 8-nitro-cGMP enhanced the mRNA expression of RANK, the receptor for RANKL. However, 8-bromo-cGMP, a membrane-permeable derivative of cGMP, did not have an effect on either RANKL-induced osteoclast differentiation or expression of the RANK gene. These results suggest that 8-nitro-cGMP is a novel positive regulator of osteoclast differentiation, which might help to explain the roles of NO and ROS in osteoclast differentiation.

Evaluation of an e-learning system for diagnosis of gastric lesions using magnifying narrow-band imaging: a multicenter randomized controlled study

Background and study aim Magnifying narrow-band imaging (M-NBI) is useful for the accurate diagnosis of early gastric cancer (EGC). However, acquiring skill at M-NBI diagnosis takes substantial effort. An Internet-based e-learning system to teach endoscopic diagnosis of EGC using M-NBI has been developed. This study evaluated its effectiveness. Participants and methods This study was designed as a multicenter randomized controlled trial. We recruited endoscopists as participants from all over Japan. After completing Test 1, which consisted of M-NBI images of 40 gastric lesions, participants were randomly assigned to the e-learning or non-e-learning groups. Only the e-learning group was allowed to access the e-learning system. After the e-learning period, both groups received Test 2. The analysis set was participants who scored < 80 % accuracy on Test 1. The primary end point was the difference in accuracy between Test 1 and Test 2 for the two groups. Results A total of 395 participants from 77 institutions completed Test 1 (198 in the e-learning group and 197 in the non-e-learning group). After the e-learning period, all 395 completed Test 2. The analysis sets were e-learning group: n = 184; and non-e-learning group: n = 184. The mean Test 1 score was 59.9 % for the e-learning group and 61.7 % for the non-e-learning group. The change in accuracy in Test 2 was significantly higher in the e-learning group than in the non-e-learning group (7.4 points vs. 0.14 points, respectively; P < 0.001). Conclusion This study clearly demonstrated the efficacy of the e-learning system in improving practitioners' capabilities to diagnose EGC using M-NBI.Trial registered at University Hospital Medical Information Network Clinical Trials Registry (UMIN000008569).