Search for B^{-}→μ^{-}ν[over ¯]_{μ} Decays at the Belle Experiment

We report the results of a search for the rare, purely leptonic decay B^{-}→μ^{-}ν[over ¯]_{μ} performed with a 711  fb^{-1} data sample that contains 772×10^{6}  BB[over ¯] pairs, collected near the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic B-meson decay, as well as the missing energy and momentum being consistent with the hypothesis of a neutrino from the signal decay. We find a 2.4 standard deviation excess above background including systematic uncertainties, which corresponds to a branching fraction of B(B^{-}→μ^{-}ν[over ¯]_{μ})=(6.46±2.22±1.60)×10^{-7} or a frequentist 90% confidence level interval on the B^{-}→μ^{-}ν[over ¯]_{μ} branching fraction of [2.9,10.7]×10^{-7}.

Role of the Apparent Diffusion Coefficient as a Predictor of Tumor Progression in Patients with Chordoma

BACKGROUND AND PURPOSE

Diffusion-weighted imaging may aid in distinguishing aggressive chordoma from nonaggressive chordoma. This study explores the prognostic role of the apparent diffusion coefficient in chordomas.

MATERIALS AND METHODS

Sixteen patients with residual or recurrent chordoma were divided postoperatively into those with an aggressive tumor, defined as a growing tumor having a doubling time of <1 year, and those with a nonaggressive tumor on follow-up MR images. The ability of the ADC to predict an aggressive tumor phenotype was investigated by receiver operating characteristic analysis. The prognostic role of ADC was assessed using a Kaplan-Meier curve with a log-rank test.

RESULTS

Seven patients died during a median follow-up of 48 months (range, 4-126 months). Five of these 7 patients were in the aggressive tumor group, and 2 were in the nonaggressive tumor group. The mean ADC was significantly lower in the aggressive tumor group than in the nonaggressive tumor group (P = .002). Receiver operating characteristic analysis showed that a cutoff ADC value of 1.494 × 10^-3 × mm²/s could be used to diagnose aggressive tumors with an area under the curve of 0.983 (95% CI, 0.911-1.000), a sensitivity of 1.000 (95% CI, 0.541-1.000), and a specificity of 0.900 (95% CI, 0.555-0.998). Furthermore, a cutoff ADC of ≤1.494 × 10^-3 × mm²/s was associated with a significantly worse prognosis (P = .006).

CONCLUSIONS

Lower ADC values could predict tumor progression in postoperative chordomas.

The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study

Objectives

To compare the effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament (ACL) reconstruction animal model.

Methods

Anterior cruciate ligament reconstruction using the plantaris tendon as graft material was performed on both knees of 24 rabbits (48 knees) to mimic ACL reconstruction by two different suspensory fixation devices for graft fixation. For the adjustable fixation device model (Socket group; group S), a 5 mm deep socket was created in the lateral femoral condyle (LFC) of the right knee. For the fixed-loop model (Tunnel group; group T), a femoral tunnel penetrating the LFC was created in the left knee. Animals were sacrificed at four and eight weeks after surgery for histological evaluation and biomechanical testing.

Results

Histologically, both groups showed a mixture of direct and indirect healing patterns at four weeks, whereas only indirect healing patterns were observed in both groups at eight weeks. No significant histological differences were seen between the two groups at four and eight weeks in the roof zone (four weeks, S: mean 4.8 sd 1.7, T: mean 4.5 sd 0.5, p = 0.14; eight weeks, S: mean 5.8 sd 0.8, T: mean 4.8 sd 1.8, p = 0.88, Mann-Whitney U test) or side zone (four weeks, S: mean 5.0 sd 1.2, T: mean 4.8 sd 0.4, p = 0.43; eight weeks, S: mean 5.3 sd 0.8,T: mean 5.5 sd 0.8, p = 0.61, Mann-Whitney U test) . Similarly, no significant difference was seen in the maximum failure load between group S and group T at four (15.6 sd 9.0N and 13.1 sd 5.6N) or eight weeks (12.6 sd 3.6N and 17.1 sd 6.4N, respectively).

Conclusion

Regardless of bone tunnel configuration, tendon-bone healing after ACL reconstruction primarily occurred through indirect healing. No significant histological or mechanical differences were observed between adjustable and fixed-loop femoral cortical suspension methods.

Cite this article: Y. Sato, R. Akagi, Y. Akatsu, Y. Matsuura, S. Takahashi, S. Yamaguchi, T. Enomoto, R. Nakagawa, H. Hoshi, T. Sasaki, S. Kimura, Y. Ogawa, A. Sadamasu, S. Ohtori, T. Sasho. The effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament reconstruction: An animal study. Bone Joint Res 2018;7:327–335. DOI: 10.1302/2046-3758.75.BJR-2017-0238.R2.

The induced RNA-binding protein, HuR, targets 3'-UTR region of IL-6 mRNA and enhances its stabilization in periodontitis

RNA-binding proteins (RBPs) regulate mRNA stability by binding to the 3'-untranslated region (UTR) region of mRNA. Human antigen-R (HuR), one of the RBPs, is involved in the progression of diseases, such as rheumatoid arthritis, diabetes mellitus and some inflammatory diseases. Interleukin (IL)-6 is a major inflammatory cytokine regulated by HuR binding to mRNA. Periodontal disease (PD) is also an inflammatory disease caused by elevations in IL-6 following an infection by periodontopathogenic bacteria. The involvement of HuR in the progression of PD was assessed using in-vitro and in-vivo experiments. Immunohistochemistry of inflamed periodontal tissue showed strong staining of HuR in the epithelium and connective tissue. HuR mRNA and protein level was increased following stimulation with Porphyromonas gingivalis (Pg), one of the periodontopathogenic bacteria, lipopolysacchride (LPS)-derived from Pg (PgLPS) and tumour necrosis factor (TNF)-α in OBA-9, an immortalized human gingival epithelial cell. The luciferase activity of 3'-UTR of IL-6 mRNA was increased by TNF-α, Pg and PgLPS in OBA-9. Luciferase activity was also increased in HuR-over-expressing OBA-9 following a bacterial stimulation. Down-regulation of HuR by siRNA resulted in a decrease in mRNA expression and production of IL-6. In contrast, the over-expression of HuR increased IL-6 mRNA expression and production in OBA-9. The HuR inhibitor, quercetin, suppressed Pg-induced HuR mRNA expression and IL-6 production in OBA-9. An oral inoculation with quercetin also inhibited bone resorption in ligature-induced periodontitis model mice as a result of down-regulation of IL-6. These results show that HuR modulates inflammatory responses by regulating IL-6.

Lipoteichoic acids are embedded in cell walls during logarithmic phase, but exposed on membrane vesicles in Lactobacillus gasseri JCM 1131T

Lipoteichoic acid (LTA) is a cell surface molecule specific to Gram-positive bacteria. How LTA localises on the cell surface is a fundamental issue in view of recognition and immunomodulation in hosts. In the present study, we examined LTA localisation using strain JCM 1131T of Lactobacillus gasseri, which is a human intestinal lactic acid bacterium, during various growth phases by immunoelectron microscopy. We first evaluated the specificity of anti-LTA monoclonal antibody clone 55 used as a probe. The glycerophosphate backbone comprising almost intact size (20 to 30 repeating units) of LTA was required for binding. The antibody did not bind to other cellular components, including wall-teichoic acid. Immunoelectron microscopy indicated that LTA was embedded in the cell wall during the logarithmic phase, and was therefore not exposed on the cell surface. Similar results were observed for Lactobacillus fermentum ATCC 9338 and Lactobacillus rhamnosus ATCC 7469T. By contrast, membrane vesicles were observed in the logarithmic phase of L. gasseri with LTA exposed on their surface. In the stationary and death phases, LTA was exposed on cell wall-free cell membrane generated by autolysis. The dramatic alternation of localisation in different growth phases and exposure on the surface of membrane vesicles should relate with complicated interaction between bacteria and host.

Results of an international comparison of activity measurements of 68Ge

An international key comparison, identifier CCRI(II)-K2.Ge-68, has been performed. The National Institute of Standards and Technology (NIST) served as the pilot laboratory, distributing aliquots of a 68Ge/68Ga solution. Results for the activity concentration, CA, of 68Ge at a reference date of 12h00 UTC 14 November 2014 were submitted by 17 laboratories, encompassing many variants of coincidence methods and liquid-scintillation counting methods. The first use of 4π(Cherenkov)β-γ coincidence and anticoincidence methods in an international comparison is reported. One participant reported results by secondary methods only. Two results, both utilizing pure liquid-scintillation methods, were identified as outliers. Evaluation using the Power-Moderated Mean method results in a proposed Comparison Reference Value (CRV) of 621.7(11)kBqg-1, based on 14 results. The degrees of equivalence and their associated uncertainties are evaluated for each participant. Several participants submitted 3.6mL ampoules to the BIPM to link the comparison to the International Reference System (SIR) which may lead to the evaluation of a Key Comparison Reference Value and associated degrees of equivalence.

Reliability of Wearable Two Channel CW-NIRS in Measurements of Brain Function

Multi-channel NIRS, so-called optical topography (OT), allows functional mapping of the cortex; however, it takes a long time to set optodes on the head and is relatively expensive. Thus, OT is not suitable as a screening test of brain disorders evaluating many subjects. Recently, a wearable two-channel continuous wave NIRS (CW-NIRS) device has been developed. Such a simple NIRS device may be applicable as a screening test of brain disorders; however, its reliability in measurements of brain function is not yet clear. Here, we tested a two-channel CW-NIRS, which employs single LED (800 nm) for measurement of total hemoglobin (t-Hb) changes. We measured t-Hb changes in the bilateral prefrontal cortex (PFC) during mental arithmetic tasks, employing the CW-NIRS and time-resolve NIRS (TNIRS). The left-right asymmetry of the PFC activity was evaluated by calculating the laterality index (LI; (R-L)/(R + L) of t-Hb), which reflects mental stress. The interval between CW-NIRS and TNIRS measurements was 1-13 days. A significant positive correlation was observed between LI measured by CW-NIRS and TNIRS. These results suggest the reliability of the simple CW-NIRS, and it may be applicable to prevent stress-induced various diseases. Finally, it should be emphasized that the left-right asymmetry of PFC activity is relatively stable.

Full-layer mucosal histology in achalasia: Histological epithelial wave is characteristic in "pinstripe pattern"-positive achalasia

BACKGROUND

Previously, the mucosal histology in achalasia has only been investigated using superficial biopsy or surgically resected esophageal specimens in end-stage cases. We investigated the histology of the full-layer mucosa in early and advanced achalasia.

METHODS

Endoscopy was performed for the pinstripe pattern (PSP) (an early achalasia indicator) and dilation and thickening of the mucosa (advanced achalasia indicators). A mucosal entry site for peroral endoscopic myotomy was created using cap-fitted endoscopic mucosal resection to access the full-layer mucosa and the submucosa.

KEY RESULTS

Mucosal histology was compared between 32 patients with achalasia and 15 controls. Histological esophagitis with findings of inflammatory cell infiltration and dilated intercellular spaces was observed more in patients with achalasia than in controls (87.5% vs 13.3%, P<.001; 84.4% vs 46.7%, P=.049). Muscularis mucosae (MM) atrophy and epithelial wave were only observed in achalasia (40.6% vs 0%, P=.005; 28.1% vs 0%, P=.043). Fibrosis was more common in achalasia, but without statistical significance (31.3% vs 20.0%, P=.503). In achalasia with endoscopic dilation and thickening of the mucosa, MM atrophy was observed histologically, and in cases involving endoscopic PSP, the histological epithelial wave was observed.

CONCLUSIONS & INFERENCES

Histological findings of esophagitis were observed endoscopically even in early achalasia. Pinstripe pattern corresponds to the epithelial wave observed histologically in achalasia, whereas endoscopic findings in advanced achalasia correspond to MM atrophy. Appropriate management is necessary during early achalasia to prevent progression to advanced achalasia with more severe histological changes.

Dynamic behaviour of the soft palate during nasal positive pressure ventilation under anaesthesia and paralysis: comparison between patients with and without obstructive sleep-disordered breathing

BACKGROUND

Difficult mask ventilation is common and is known to be associated with sleep-disordered breathing (SDB). It is our hypothesis that the incidence of expiratory retropalatal (RP) airway closure (primary outcome) during nasal positive pressure ventilation (PPV) is more frequent in patients with SDB (apnea hypopnea index ≥5 h^-1) than non-SDB subjects.

METHODS

The severity of SDB was assessed before surgery using a portable sleep monitor. In anaesthetized and paralysed patients with (n=11) and without SDB (n=9), we observed the behaviour of the RP airway endoscopically during nasal PPV with the mouth closed and determined the dynamic RP closing pressure, which was defined as the highest airway pressure above which the RP airway closure was reversed. The static RP closing pressure was obtained during cessation of mechanical ventilation in patients with dynamic RP closure during nasal PPV.

RESULTS

The expiratory RP airway closure accompanied by expiratory flow limitation occurred more frequently in SDB patients (9/11, 82%) than in non-SDB subjects (2/9, 22%; exact logistic regression analysis: P=0.022, odds ratio 3.6, 95% confidence interval 1.1-15.4). Receiver operating characteristic curve analyses indicated AHI >10h^-1 and presence of habitual snoring as clinically useful predictors for the occurrence of RP closure during PPV. Dynamic RP closing pressure was greater than the static RP closing pressure by approximately 4-5 cm H₂O.

CONCLUSIONS

Valve-like dynamic RP closure that limits expiratory flow during nasal PPV occurs more frequently in SDB patients.

Changes in esophageal motility after endoscopic submucosal dissection for superficial esophageal cancer: a high-resolution manometry study

The effect of endoscopic submucosal dissection (ESD) on esophageal motility remains unknown. Therefore, the aim of this study is to elucidate changes in esophageal motility after ESD along with the cause of dysphagia using high-resolution manometry (HRM). This is a before-and-after trial of the effect of ESD on the esophageal motility. Twenty patients who underwent ESD for superficial esophageal carcinoma were enrolled in this study. Patients filled out a questionnaire about dysphagia and underwent HRM before and after ESD. Results before and after ESD were compared. Data were obtained from 19 patients. The number of patients who complained of dysphagia before and after ESD was 1/19 (5.3%) and 6/19 (31.6%), respectively (P = 0.131). Scores from the five-point Likert scale before and after ESD were 0.1 ± 0.5 and 1.0 ± 1.6, respectively (P = 0.043). The distal contractile integral (DCI) before and after ESD and the number of failed, weak, or fragmented contractions were not significantly different. However, in five patients with circumferential ESD, DCI was remarkably decreased and the frequency of fail, weak, or fragmented contractions increased. Univariate regression analysis showed a relatively strong inverse correlation of ΔDCI with the circumferential mucosal defect ratio {P < 0.01, standardized regression coefficient (r) = -0.65}, the number of stricture preventions (P < 0.01, r = -0.601), and the number of stricture resolutions (P < 0.01, r = -0.77). This HRM study showed that impairment of esophageal motility could be caused by ESD. The impairment of esophageal motility was conspicuous, especially in patients with circumferential ESD and subsequent procedures such as endoscopic triamcinolone injection and endoscopic balloon dilatation. Impaired esophageal motility after ESD might explain dysphagia.

Search for CP Violation and Measurement of the Branching Fraction in the Decay D^{0}→K_{S}^{0}K_{S}^{0}

We report a study of the decay D^{0}→K_{S}^{0}K_{S}^{0} using 921  fb^{-1} of data collected at or near the ϒ(4S) and ϒ(5S) resonances with the Belle detector at the KEKB asymmetric energy e^{+}e^{-} collider. The measured time-integrated CP asymmetry is A_{CP}(D^{0}→K_{S}^{0}K_{S}^{0})=(-0.02±1.53±0.02±0.17)%, and the branching fraction is B(D^{0}→K_{S}^{0}K_{S}^{0})=(1.321±0.023±0.036±0.044)×10^{-4}, where the first uncertainty is statistical, the second is systematic, and the third is due to the normalization mode (D^{0}→K_{S}^{0}π^{0}). These results are significantly more precise than previous measurements available for this mode. The A_{CP} measurement is consistent with the standard model expectation.

Predictive models for conversion of prediabetes to diabetes

AIM

To clarify the natural course of prediabetes and develop predictive models for conversion to diabetes.

METHODS

A retrospective longitudinal study of 2105 adults with prediabetes was carried out with a mean observation period of 4.7years. Models were developed using multivariate logistic regression analysis and verified by 10-fold cross-validation. The relationship between [final BMI minus baseline BMI] (δBMI) and incident diabetes was analyzed post hoc by comparing the diabetes conversion rate for low (< -0.31kg/m²) and high δBMI (≥ -0.31kg/m²) subjects after matching the two groups for the covariates.

RESULTS

Diabetes developed in 252 (2.5%/year), and positive family history, male sex, higher systolic blood pressure, plasma glucose (fasting and 1h- and 2h-values during 75g OGTT), hemoglobin A1c (HbA1c) and alanine aminotransferase were significant, independent predictors for the conversion. By using a risk score (RS) that took account of all these variables, incident diabetes was predicted with an area under the ROC curve (95% CI) of 0.80 (0.70-0.87) and a specificity of prediction of 61.8% at 80% sensitivity. On division of the participants into high- (n=248), intermediate- (n=336) and low-risk (n=1521) populations, the conversion rates were 40.1%, 18.5% and 5.9%, respectively. The conversion rate was lower in subjects with low than high δBMI (9.2% vs 14.4%, p=0.003).

CONCLUSIONS

Prediabetes conversion to diabetes could be predicted with accuracy, and weight reduction during the observation was associated with lowered conversion rate.

Biological effects of anti-RANKL antibody administration in pregnant mice and their newborns

Denosumab, a fully human monoclonal antibody that neutralizes receptor activator of nuclear factor-κB ligand (RANKL) and blocks osteoclast differentiation, has received approval in Japan for use as an anti-resorptive drug for osteoporosis and skeletal-related events (SREs) in patients with solid cancer. Denosumab is contraindicated during pregnancy, though the effects of blocking RANKL activity on pregnant mothers and their newborns are unclear. We used mice to investigate the effects of an anti-RANKL antibody on maternal and newborn health. Mothers injected with the anti-RANKL antibody had increased bone mass as compared with the controls, while osteoclast number and the level of tartrate-resistant acid phosphatase (TRAP) in serum were increased at the end of pregnancy. Newborn mice exposed to the antibody in utero were normally born, but showed increased bone mass and died within 48 h after birth. None of the newborns were found to have milk in their stomachs, suggesting that they died due to a maternal defect in lactation. Consistent with this, anti-RANKL antibody-injected mothers displayed impaired mammary gland development. However, fostering by healthy surrogate mothers rescued only 33% of the antibody-exposed newborns, suggesting that neonatal mortality was due, at least in part, to an intrinsic defect in the newborns. Our findings show that anti-RANKL antibody administration during pregnancy results in not only an undesirable increase in bone mass, but also has harmful effects on newborn survival.

Stochastic Chaos in a Turbulent Swirling Flow

We report the experimental evidence of the existence of a random attractor in a fully developed turbulent swirling flow. By defining a global observable which tracks the asymmetry in the flux of angular momentum imparted to the flow, we can first reconstruct the associated turbulent attractor and then follow its route towards chaos. We further show that the experimental attractor can be modeled by stochastic Duffing equations, that match the quantitative properties of the experimental flow, namely, the number of quasistationary states and transition rates among them, the effective dimensions, and the continuity of the first Lyapunov exponents. Such properties can be recovered neither using deterministic models nor using stochastic differential equations based on effective potentials obtained by inverting the probability distributions of the experimental global observables. Our findings open the way to low-dimensional modeling of systems featuring a large number of degrees of freedom and multiple quasistationary states.

Chlorogenic acid supplementation during in vitro maturation improves maturation, fertilization and developmental competence of porcine oocytes

Chlorogenic acid (CGA) is a quinic acid conjugate of caffeic acid, and a phytochemical found in many fruits and beverages that acts as an antioxidant. The present study investigated the effects of CGA supplementation during in vitro maturation (IVM), on in vitro development of porcine oocytes, to improve the porcine in vitro production (IVP) system. Oocytes were matured either without (control) or with CGA (10, 50, 100 and 200 μM). Subsequently, the matured oocytes were fertilized and cultured in vitro for 7 day. The rates of maturation, fertilization and blastocyst formation of oocytes matured with 50 μM CGA were significantly (p < .05) higher than those of the control oocytes. Hydrogen peroxide (H₂ O₂ ) is one of the reactive oxygen species and induces DNA damage in porcine oocytes. When oocytes were matured with 1 mM H₂ O₂ to assess the protective effect of CGA, 50 μM CGA supplementation improved the maturation rate and the proportion of DNA-fragmented nuclei in oocytes compared with control oocytes matured without CGA. Moreover, when oocytes were matured with either 50 μM CGA (control) or caffeic acid (10, 50 and 100 μM), the rates of maturation, fertilization and the blastocyst formation of oocytes matured with 50 μM CGA were similar to those of oocytes matured with 10 and 50 μM caffeic acid. Our results suggest that CGA has comparable effects to caffeic acid, and IVM with 50 μM CGA is particularly beneficial to IVP of porcine embryos and protects oocytes from DNA damage induced by oxidative stress. Supplementation of CGA to the maturation medium has a potential to improve porcine IVP system.

Dental Status and Compression of Life Expectancy with Disability

This study examined whether the number of teeth contributes to the compression of morbidity, measured as a shortening of life expectancy with disability, an extension of healthy life expectancy, and overall life expectancy. A prospective cohort study was conducted. A self-reported baseline survey was given to 126,438 community-dwelling older people aged ≥65 y in Japan in 2010, and 85,161 (67.4%) responded. The onset of functional disability and all-cause mortality were followed up for 1,374 d (follow-up rate = 96.1%). A sex-stratified illness-death model was applied to estimate the adjusted hazard ratios (HRs) for 3 health transitions (healthy to dead, healthy to disabled, and disabled to dead). Absolute differences in life expectancy, healthy life expectancy, and life expectancy with disability according to the number of teeth were also estimated. Age, denture use, socioeconomic status, health status, and health behavior were adjusted. Compared with the edentulous participants, participants with ≥20 teeth had lower risks of transitioning from healthy to dead (adjusted HR, 0.58 [95% confidence interval (CI), 0.50-0.68] for men and 0.70 [95% CI, 0.57-0.85] for women) and from healthy to disabled (adjusted HR, 0.52 [95% CI, 0.44-0.61] for men and 0.58 [95% CI, 0.49-0.68] for women). They also transitioned from disabled to dead earlier (adjusted HR, 1.26 [95% CI, 0.99-1.60] for men and 2.42 [95% CI, 1.72-3.38] for women). Among the participants aged ≥85 y, those with ≥20 teeth had a longer life expectancy (men: +57 d; women: +15 d) and healthy life expectancy (men: +92 d; women: +70 d) and a shorter life expectancy with disability (men: -35 d; women: -55 d) compared with the edentulous participants. Similar associations were observed among the younger participants and those with 1 to 9 or 10 to 19 teeth. The presence of remaining teeth was associated with a significant compression of morbidity: older Japanese adults' life expectancy with disability was compressed by 35 to 55 d within the follow-up of 1,374 d.

Intra- and inter-tester reliability and validity of normal finger size measurement using the Japanese ring gauge system

This study was designed to investigate the reliability and validity of measurements of finger diameters with a ring gauge. A reliability study enrolled two independent samples (50 participants and seven examiners in Study I; 26 participants and 26 examiners in Study II). The sizes of each participant's little fingers were measured twice with a ring gauge by each examiner. To investigate the validity of the measurements, five hand therapists compared the finger size and hand volume of 30 participants with the ring gauge and with a figure-of-eight technique (Study III). The intra-class correlation coefficient for intra-observer reliability ranged from 0.97 to 0.99 in Study I, and 0.90 to 0.97 in Study II. The intra-class correlation coefficient for inter-observer reliability was 0.95 in Study I and 0.94 in Study II. The validity study showed a Pearson product moment correlation coefficient of 0.75. The ring gauge showed high reliability and validity for measurement of finger size.

LEVEL OF EVIDENCE

III, diagnostic.