Evaluation of QSAR models for predicting mutagenicity: outcome of the Second Ames/QSAR international challenge project.

Quantitative structure-activity relationship (QSAR) models are powerful in silico tools for predicting the mutagenicity of unstable compounds, impurities and metabolites that are difficult to examine using the Ames test. Ideally, Ames/QSAR models for regulatory use should demonstrate high sensitivity, low false-negative rate and wide coverage of chemical space. To promote superior model development, the Division of Genetics and Mutagenesis, National Institute of Health Sciences, Japan (DGM/NIHS), conducted the Second Ames/QSAR International Challenge Project (2020-2022) as a successor to the First Project (2014-2017), with 21 teams from 11 countries participating. The DGM/NIHS provided a curated training dataset of approximately 12,000 chemicals and a trial dataset of approximately 1,600 chemicals, and each participating team predicted the Ames mutagenicity of each trial chemical using various Ames/QSAR models. The DGM/NIHS then provided the Ames test results for trial chemicals to assist in model improvement. Although overall model performance on the Second Project was not superior to that on the First, models from the eight teams participating in both projects achieved higher sensitivity than models from teams participating in only the Second Project. Thus, these evaluations have facilitated the development of QSAR models.

Development of advanced photon calibrator for Kamioka gravitational wave detector (KAGRA).

The Kamioka Gravitational wave detector (KAGRA) cryogenic gravitational-wave observatory has commenced joint observations with the worldwide gravitational wave detector network. Precise calibration of the detector response is essential for accurately estimating parameters of gravitational wave sources. A photon calibrator is a crucial calibration tool used in laser interferometer gravitational-wave observatory, Virgo, and KAGRA, and it was utilized in joint observation 3 with GEO600 in Germany in April 2020. In this paper, KAGRA implemented three key enhancements: a high-power laser, a power stabilization system, and remote beam position control. KAGRA employs a 20 W laser divided into two beams that are injected onto the mirror surface. By utilizing a high-power laser, the response of the detector at kHz frequencies can be calibrated. To independently control the power of each laser beam, an optical follower servo was installed for power stabilization. The optical path of the photon calibrator's beam positions was controlled using pico-motors, allowing for the characterization of the detector's rotation response. Additionally, a telephoto camera and quadrant photodetectors were installed to monitor beam positions, and beam position control was implemented to optimize the mirror response. In this paper, we discuss the statistical errors associated with the measurement of relative power noise. We also address systematic errors related to the power calibration model of the photon calibrator and the simulation of elastic deformation effects using finite element analysis. Ultimately, we have successfully reduced the total systematic error from the photon calibrator to 2.0%.

Differential Cross Section and Photon-Beam Asymmetry for the γ[over →]p → π

Differential cross sections and photon-beam asymmetries for the γ[over →]p→π^{-}Δ^{++}(1232) reaction have been measured for 0.7

Comparative evaluation of topographical data of dental implant surfaces applying optical interferometry and scanning electron microscopy.

OBJECTIVE: Comparability of topographical data of implant surfaces in literature is low and their clinical relevance often equivocal. The aim of this study was to investigate the ability of scanning electron microscopy and optical interferometry to assess statistically similar 3-dimensional roughness parameter results and to evaluate these data based on predefined criteria regarded relevant for a favorable biological response. METHODS: Four different commercial dental screw-type implants (NanoTite Certain Prevail, TiUnite Brånemark Mk III, XiVE S Plus and SLA Standard Plus) were analyzed by stereo scanning electron microscopy and white light interferometry. Surface height, spatial and hybrid roughness parameters (Sa, Sz, Ssk, Sku, Sal, Str, Sdr) were assessed from raw and filtered data (Gaussian 50µm and 5µm cut-off-filters), respectively. Data were statistically compared by one-way ANOVA and Tukey-Kramer post-hoc test. For a clinically relevant interpretation, a categorizing evaluation approach was used based on predefined threshold criteria for each roughness parameter. RESULTS: The two methods exhibited predominantly statistical differences. Dependent on roughness parameters and filter settings, both methods showed variations in rankings of the implant surfaces and differed in their ability to discriminate the different topographies. Overall, the analyses revealed scale-dependent roughness data. Compared to the pure statistical approach, the categorizing evaluation resulted in much more similarities between the two methods. SIGNIFICANCE: This study suggests to reconsider current approaches for the topographical evaluation of implant surfaces and to further seek after proper experimental settings. Furthermore, the specific role of different roughness parameters for the bioresponse has to be studied in detail in order to better define clinically relevant, scale-dependent and parameter-specific thresholds and ranges.

Liver-related safety assessment of green tea extracts in humans: a systematic review of randomized controlled trials.

There remain liver-related safety concerns, regarding potential hepatotoxicity in humans, induced by green tea intake, despite being supposedly beneficial. Although many randomized controlled trials (RCTs) of green tea extracts have been reported in the literature, the systematic reviews published to date were only based on subjective assessment of case reports. To more objectively examine the liver-related safety of green tea intake, we conducted a systematic review of published RCTs. A systematic literature search was conducted using three databases (PubMed, EMBASE and Cochrane Central Register of Controlled Trials) in December 2013 to identify RCTs of green tea extracts. Data on liver-related adverse events, including laboratory test abnormalities, were abstracted from the identified articles. Methodological quality of RCTs was assessed. After excluding duplicates, 561 titles and abstracts and 119 full-text articles were screened, and finally 34 trials were identified. Of these, liver-related adverse events were reported in four trials; these adverse events involved seven subjects (eight events) in the green tea intervention group and one subject (one event) in the control group. The summary odds ratio, estimated using a meta-analysis method for sparse event data, for intervention compared with placebo was 2.1 (95% confidence interval: 0.5-9.8). The few events reported in both groups were elevations of liver enzymes. Most were mild, and no serious liver-related adverse events were reported. Results of this review, although not conclusive, suggest that liver-related adverse events after intake of green tea extracts are expected to be rare.

Exome sequencing for bipolar disorder points to roles of de novo loss-of-function and protein-altering mutations.

Although numerous genetic studies have been conducted for bipolar disorder (BD), its genetic architecture remains elusive. Here we perform, to the best of our knowledge, the first trio-based exome sequencing study for BD to investigate potential roles of de novo mutations in the disease etiology. We identified 71 de novo point mutations and one de novo copy-number mutation in 79 BD probands. Among the genes hit by de novo loss-of-function (LOF; nonsense, splice site or frameshift) or protein-altering (LOF, missense and inframe indel) mutations, we found significant enrichment of genes highly intolerant (first percentile of intolerant genes assessed by Residual Variation Intolerance Score) to protein-altering variants in general population, an observation that is also reported in autism and schizophrenia. When we performed a joint analysis using the data of schizoaffective disorder in published studies, we found global enrichment of de novo LOF and protein-altering mutations in the combined group of bipolar I and schizoaffective disorders. Considering relationship between de novo mutations and clinical phenotypes, we observed significantly earlier disease onset among the BD probands with de novo protein-altering mutations when compared with non-carriers. Gene ontology enrichment analysis of genes hit by de novo protein-altering mutations in bipolar I and schizoaffective disorders did not identify any significant enrichment. These results of exploratory analyses collectively point to the roles of de novo LOF and protein-altering mutations in the etiology of bipolar disorder and warrant further large-scale studies.

Endovascular Treatment for Infra-inguinal Autologous Saphenous Vein Graft Occlusion Using Self Expanding Nitinol Stents.

INTRODUCTION: For patients with infra-inguinal autologous vein bypass graft occlusion, conventional open surgical repair or endovascular treatment (EVT) for native vessel occlusion have generally been performed. REPORT: A 73 year old female with non-healing ulcer and gangrene of the left lower leg was diagnosed as having infra-inguinal autologous saphenous vein graft occlusion. In this case, surgical repair such as patch angioplasty, interposition graft, or replacement graft did not seem promising because of repeated previous infection in the polytetrafluoroethylene (PTFE) vascular prosthesis and absence of available autologous vein due to past surgery. Moreover, there was no chance of crossing the native vessel, since the proximal superficial femoral artery (SFA) had already been resected. Thus, EVT was performed for the occluded autologous vein graft, implanting multiple self expanding bare nitinol stents throughout the vein graft achieving complete revascularization, good medium term patency, and dramatically improved wound healing. CONCLUSION: Endovascular recanalization using multiple bare stents could be an alternative treatment for infra-inguinal autologous vein graft occlusion.

Depression-like episodes in mice harboring mtDNA deletions in paraventricular thalamus.

Depression is a common debilitating human disease whose etiology has defied decades of research. A critical bottleneck is the difficulty in modeling depressive episodes in animals. Here, we show that a transgenic mouse with chronic forebrain expression of a dominant negative mutant of Polg1, a mitochondrial DNA (mtDNA) polymerase, exhibits lethargic behavioral changes, which are associated with emotional, vegetative and psychomotor disturbances, and response to antidepression drug treatment. The results suggested a symptomatic similarity between the lethargic behavioral change that was recurrently and spontaneously experienced by the mutant mice and major depressive episode as defined by DSM-5. A comprehensive screen of mutant brain revealed a hotspot for mtDNA deletions and mitochondrial dysfunction in the paraventricular thalamic nucleus (PVT) with similar defects observed in postmortem brains of patients with mitochondrial disease with mood symptoms. Remarkably, the genetic inhibition of PVT synaptic output by Cre-loxP-dependent expression of tetanus toxin triggered de novo depression-like episodes. These findings identify a novel preclinical mouse model and brain area for major depressive episodes with mitochondrial dysfunction as its cellular mechanism.

The impact of the number of occult metastatic lymph nodes on postoperative relapse of resectable esophageal cancer.

Clinical stage II/III esophageal cancer (EC), as defined by the Japanese Classification, relapses at a moderately high rate even after curative resection. The number of lymph node metastases is known to be associated with tumor relapse. Recently, the prognostic significance of occult metastatic lymph nodes (MLNs), as well as that of overt MLNs, has been reported. The aim of this study was to investigate the impact of the total number of MLNs including occult MLNs on postoperative relapse in clinical stage II/III EC. One hundred and five patients with clinical stage II/III EC who underwent esophagectomy accompanied by radical lymphadenectomy at the Department of Surgical Oncology in Osaka City University Hospital between January 2000 and October 2008 were included in this study. Occult MLNs, metastases not detected by hematoxylin-eosin staining, were identified by immunohistochemistry (IHC) using antipancytokeratin antibody AE1/AE3. The clinicopathological features of occult MLNs were compared between the relapse and no relapse groups. A total of 6558 lymph nodes (1357 from two-field dissection and 5201 from three-field dissection) were examined by IHC staining; 362 overt MLNs and 143 occult MLNs were detected. The number of occult MLNs increased in proportion to the International Union Against Cancer pathological (p)N-status and pStage. When the number of occult MLNs was added to the number of pNs, the number of total MLNs was associated with postoperative relapse. With respect to tumor, node, metastasis stage, 6 of 22 patients (27%) who were pathological node-negative converted to node-positive by considering total MLNs. The number of N3 patients with relapse increased markedly with restaging by total MLNs. The number of total MLNs, but not overt MLNs, was an independent prognostic factor on multivariate analysis. These results suggest that occult MLNs were often found, and they were associated with postoperative relapse of resectable esophageal cancer. The total number of MLNs including occult MLNs could contribute to evaluating the precise stage of patients with esophageal cancer.

Herd prevalence of Enterobacteriaceae producing CTX-M-type and CMY-2 ß-lactamases among Japanese dairy farms.

AIMS: To determine the herd prevalence of Enterobacteriaceae producing CTX-M-type extended-spectrum ß-lactamases (ESBLs) among 381 dairy farms in Japan. METHODS AND RESULTS: Between 2007 and 2009, we screened 897 faecal samples using BTB lactose agar plates containing cefotaxime (2 µg ml(-1)). Positive isolates were tested using ESBL confirmatory tests, PCR and sequencing for CTX-M, AmpC, TEM and SHV. The incidence of Enterobacteriaceae producing CTX-M-15 (n = 7), CTX-M-2 (n = 12), CTX-M-14 (n = 3), CMY-2 (n = 2) or CTX-M-15/2/14 and CMY-2 (n = 4) in bovine faeces was 28/897 (3·1%) faecal samples. These genes had spread to Escherichia coli (n = 23) and three genera of Enterobacteriaceae (n = 5). Herd prevalence was found to be 20/381 (5·2%) dairy farms. The 23 E. coli isolates showed clonal diversity, as assessed by multilocus sequence typing and pulsed-field gel electrophoresis. The pandemic E. coli strain ST131 producing CTX-M-15 or CTX-M-27 was not detected. CONCLUSIONS: Three clusters of CTX-M (CTX-M-15, CTX-M-2, CTX-M-14) had spread among Japanese dairy farms. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on the prevalence of multidrug-resistant CTX-M-15-producing E. coli among Japanese dairy farms.

Epalrestat improves diabetic wound healing via increased expression of nerve growth factor.

AIMS/INTRODUCTION: Aldose reductase inhibitors (ARIs) are a useful therapy for diabetic neuropathy. Nerve damage is associated with delayed wound healing of skin ulcers in diabetic patients. Therefore, we hypothesized that ARI supplementation would improve diabetic wound healing. MATERIALS AND METHODS: Control and streptozotocin-induced diabetic mice were fed either control diet or diet containing the ARI Epalrestat (40 mg/kg). After 12 weeks, we created skin wounds on the backs of the mice. Wound healing was determined by measuring the reduction in wound area. RESULTS: The wound gap of the diabetic group was significantly larger 9 days after creating the wounds when compared to the other groups (p<0.01). Interestingly, wound healing in the diabetic mice fed Epalrestat was comparable to the non-diabetic mice. To clarify the mechanism(s) behind this improved wound healing, mRNA expression of growth factors reported to be involved in wound healing were examined. Among the growth factors investigated, only the expression of nerve growth factor (NGF) was -significantly decreased (54.0%) in the healing lesions of diabetic mice. Similarly, NGF protein expression was decreased in diabetic mice and recovered in Epalrestat treated diabetic mice. Inhibition of NGF via 2 separate inhibitors (K252a and BSO) reduced the ability of Epalrestat to improve wound healing in diabetic mice. CONCLUSIONS: These findings suggest that Epalrestat is a potential therapy for improving diabetic wound healing and the mechanism involves upregulation of NGF.

Potential of polar lipids from bovine milk to regulate the rodent dorsal hair cycle.

Among the lipids in bovine milk, minor components such as conjugated linoleic acids and phospholipids are more attractive than triacylglycerols from the standpoint of biological activity. To explore novel functions of bovine milk polar lipids (MPL), topical application to murine dorsal skin was introduced as an assay system. The acetone-insoluble lipid fraction derived from bovine milk was dispersed in ethanol and applied to 9-wk-old C57BL/6N female mice for 3 wk. In combination with visual assessment of the dorsal pigmentation, the progression of the hair cycle was estimated by calculating the ratio of subcutis to dermis thickness. The administration of MPL led to earlier progression of the hair cycle compared with administration of the vehicle. In some cases, the extent of MPL-induced hair cycle progression was comparable to that in animals treated with minoxidil, the most well-known reagent that initiates anagen. These results indicate that the MPL preparation contains a dermal penetrative component that can regulate the hair cycle and, thus, this preparation possesses potential for cosmetic use.

Expression of Forkhead box P3 in tumour cells causes immunoregulatory function of signet ring cell carcinoma of the stomach.

BACKGROUND: It was recently reported that the transcription factor Forkhead box P3 (FoxP3) is expressed not only in regulatory T cells (Tregs) but also in cancer cells. The aim of this study was to clarify the clinical significance of FoxP3 expression in gastric carcinoma. METHODS: We performed immunohistochemical staining of FoxP3 to examine the association of FoxP3 expression with clinicopathological features of 194 patients with gastric cancer who underwent surgical resection from 2000 to 2010. We also investigated the immunosuppressive function of FoxP3 using gastric cancer cell lines. RESULTS: Immunohistochemical staining indicated FoxP3-positive cells within tumour tissue including both Tregs and tumour cells. Forkhead box P3-positive tumour cells were observed in 79.3% of signet ring cell carcinoma patients, and the expression of FoxP3 showed a significant correlation with lymph node metastasis. We showed that transforming growth factor-ß augmented FoxP3 mRNA expression in cell lines derived from signet ring cell carcinoma. Indoleamine-2,3-dioxygenase and galectin-1, key effectors of Treg-mediated immunosuppression, were downregulated by FoxP3 knockdown. CONCLUSION: Our findings suggested that FoxP3 expression by tumour cells might have important roles in immune escape of gastric carcinoma, and be associated with the malignant potential of scirrhous gastric carcinoma.