Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of sqrt[s]=1.96  TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is A_{FB}^{tt[over ¯]}=0.128±0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.

Enhancement of Osteogenesis by Concanavalin a in Human Bone Marrow Mesenchymal Stem Cell Cultures

This study investigates concanavalin A (ConA) as a novel factor that may enhance osteogenesis of mesenchymal stem cells (MSCs) in vitro. Various factors, such as cytokine bone morphogenetic protein-2 (BMP-2), have been studied for their possible promotion of MSC osteogenesis in vivo and in vitro. However, the factor that might be safer, more effective, and less expensive than these has not been determined. We therefore cultured human MSCs in osteogenic medium in the presence or absence of ConA, and used calcium assays to compare the effects of ConA and BMP-2 on MSC calcification. We also used enzyme-linked immunosorbent assay (ELISA) and quantitative polymerase chain reaction (PCR) to evaluate the expression levels of bone-specific markers. ConA and BMP-2 enhanced calcification with comparable effectiveness. The combination of ConA and BMP-2 further enhanced calcification slightly but significantly. ConA also increased osteocalcin and BMP-2 protein levels in MSC culture medium. Furthermore, ConA increased osteocalcin, RUNX2, BMP-2, BMP-4, and BMP-6 mRNA expression levels. However, the gene expression pattern of ConA-stimulated MSCs was different from that of MSCs stimulated by BMP-2. Together, these results suggest that ConA and BMP-2 enhance MSC osteogenesis via different pathways. ConA-induced bone formation in MSC cultures may be useful in regenerative medicine or tissue engineering in clinical studies, as well as in basic research on bone formation.

Adherence to contact precautions by different types of healthcare workers through video monitoring in a tertiary hospital

BACKGROUND

Contact precautions are required to prevent transmission of multi-drug-resistant organisms; however, reports on adherence rates vary. This study used video monitoring to evaluate adherence to the use of personal protective equipment (PPE) by different types of healthcare workers.

METHODS

This observational study was conducted in a 781-bed tertiary hospital from July 2016 to March 2017. Cameras were installed in areas where staff don PPE. Infection control teams observed the videos and assessed adherence rates.

RESULTS

In total, 1097 opportunities for donning PPE were observed. Most staff observed were nurses and nursing assistants (Ns/Nsas) (880/1097, 80.2%). Overall, the adherence rate to appropriate PPE use was 34.0%. The adherence rate among Ns/Nsas was lower (239/858, 27.9%) compared with infectious disease doctors (18/18, 100%) and cleaning staff (42/49, 85.7%). The adherence rate for PPE use for Clostridium difficile infection (CDI) with toxin detection was significantly higher than that for CDI without toxin detection and multi-drug-resistant organisms (P<0.001 for both). The adherence rate for patients with an independent functional status was higher than that for patients with a dependent functional status (P=0.018). The adherence rate was lower in the intensive care unit (ICU) than in non-ICU wards (27.6% vs 36.5%; P=0.006).

CONCLUSION

Video monitoring is a useful tool for monitoring adherence to PPE use, facilitating observation of more PPE opportunities than direct observation. Adherence to contact precautions varied by occupation; however, overall adherence was insufficient. The lower adherence rate in nurses might be due to more frequent care visits.

Age-Related 12-Year Changes in Dietary Diversity and Food Intakes among Community-Dwelling Japanese Aged 40 to 79 Years

OBJECTIVES

This study describes trends in dietary diversity and food intake over 12 years according to age at first participation in the study.

DESIGN

Prospective cohort study.

SETTING

The National Institute for Longevity Sciences - Longitudinal Study of Aging, a community-based study.

PARTICIPANTS

Participants included 922 men and 879 women who participated in the first study-wave (age, 40-79 years) and also participated in at least one study-wave from the second to seventh study-wave. Study-waves were conducted biennially.

MEASUREMENTS

Dietary intake was calculated from 3-day dietary records with photographs. Dietary diversity was determined using the Quantitative Index for Dietary Diversity based on food intake. A mixed-effects model was used to estimate linear changes in dietary diversity and food intake over 12 years according to age at first study-wave.

RESULTS

Mean (standard deviation (SD)) follow-up time and number of study-wave visits were 9.5 (3.7) years and 5.4 (1.8), respectively. Mean (SD, range) dietary diversity score was 0.86 (0.06, 0.52-0.96) in men and 0.88 (0.04, 0.66-0.96) in women, respectively. Fixed effects for interactions of age and time with dietary diversity score were statistically significant (p<0.05). The slope of dietary diversity among men aged 40 to 55 years increased (40-year-old slope = 0.00093/year, p<0.01; 55-year-old slope = 0.00035/year, p=0.04), with a decreasing trend started at 65 years old, although this trend was not significant (65-year-old slope = -0.00003/year, p=0.88; 79-year-old slope = -0.00057/year, p=0.21). The slope of dietary diversity among women aged 40 to 44 years increased (40-year-old slope = 0.00053/year, p=0.02; 44-year-old slope = 0.00038/year, p=0.04), whereas the slope of dietary diversity among women aged 63 to 79 years decreased (63-year-old slope = -0.00033/year, p=0.03; 79-year-old slope = -0.00092/year, p<0.001). Fruit, milk and dairy intake decreased in men around their 60s; milk and dairy intake decreased in women around their 50s; and beans and fruit intake decreased in women from their 70s.

CONCLUSION

Twelve-year longitudinal data showed dietary diversity declined in women in their 60s. In terms of food intake, fruit, milk and dairy intake decreased in both sexes in their 50s and 60s; such declines would lower dietary diversity.

Controlling the Topological Sector of Magnetic Solitons in Exfoliated Cr_{1/3}NbS_{2} Crystals

We investigate manifestations of topological order in monoaxial helimagnet Cr_{1/3}NbS_{2} by performing transport measurements on ultrathin crystals. Upon sweeping the magnetic field perpendicularly to the helical axis, crystals thicker than one helix pitch (48 nm) but much thinner than the magnetic domain size (∼1  μm) are found to exhibit sharp and hysteretic resistance jumps. We show that these phenomena originate from transitions between topological sectors with a different number of magnetic solitons. This is confirmed by measurements on crystals thinner than 48 nm-in which the topological sector cannot change-that do not exhibit any jump or hysteresis. Our results show the ability to deterministically control the topological sector of finite-size Cr_{1/3}NbS_{2} and to detect intersector transitions by transport measurements.

Measurement of the τ Lepton Polarization and R(D^{*}) in the Decay B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ}

We report the first measurement of the τ lepton polarization P_{τ}(D^{*}) in the decay B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ} as well as a new measurement of the ratio of the branching fractions R(D^{*})=B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ}), where ℓ^{-} denotes an electron or a muon, and the τ is reconstructed in the modes τ^{-}→π^{-}ν_{τ} and τ^{-}→ρ^{-}ν_{τ}. We use the full data sample of 772×10^{6}  BB[over ¯] pairs recorded with the Belle detector at the KEKB electron-positron collider. Our results, P_{τ}(D^{*})=-0.38±0.51(stat)_{-0.16}^{+0.21}(syst) and R(D^{*})=0.270±0.035(stat)_{-0.025}^{+0.028}(syst), are consistent with the theoretical predictions of the standard model.

Association of plasma concentrations of branched-chain amino acids with risk of colorectal adenoma in a large Japanese population

Background

Available evidence from animal studies suggests that branched-chain amino acids (BCAAs) may have a protective effect against colorectal carcinogenesis. However, a possible effect of BCAAs against colorectal neoplasia has not been evaluated in humans. Here, we aimed to evaluate whether plasma concentrations of BCAA are associated with the risk of colorectal adenoma (CRA), a precursor lesion of colorectal cancer.

Patients and methods

CRA cases and controls were identified from examinees who underwent total colonoscopy as part of a cancer screening program between 2004 and 2005 and responded to self-administered dietary and lifestyle questionnaires. We measured plasma concentrations of leucine, isoleucine and valine in 629 patients with adenoma and 584 controls. Unconditional logistic regression models were used to estimate odds ratio (OR) and 95% confidence interval (CI) for the association between BCAA and CRA risk after adjustment for potential confounders.

Results

High plasma concentrations of leucine, valine and total BCAA were inversely associated with CRA risk after adjustment of potential confounders. The multivariate-adjusted ORs for the highest versus lowest quartiles were 0.60 (95% CI 0.42-0.87, Ptrend = 0.006) for leucine, 0.68 (95% CI 0.48-0.97, Ptrend = 0.09) for valine and 0.68 (95% CI 0.48-0.98, Ptrend = 0.10) for total BCAA. Further analysis by gender revealed that this inverse association was clearly evident in men, but not in women: the corresponding OR for leucine, valine and total BCAA was 0.50 (95% CI 0.32-0.80, Ptrend = 0.003), 0.60 (95% CI 0.38-0.95, Ptrend = 0.01) and 0.58 (95% CI 0.37-0.93, Ptrend = 0.04), respectively, in men and 0.78 (95% CI 0.42-1.45, Ptrend = 0.44), 0.77 (95% CI 0.41-1.43, Ptrend = 0.85) and 0.84 (95% CI 0.45-1.57, Ptrend = 0.81), respectively, in women.

Conclusion

Our finding suggests that BCAAs may have a beneficial influence against the process of colorectal carcinogenesis, at least in the early stage. The mechanisms underlying this potential association between BCAA and colorectal carcinogenesis warrant further investigation.

Impact of Portal Hemodynamic Changes in Partial Liver Grafts on Short-Term Graft Regeneration in Living Donor Liver Transplantation

BACKGROUND

Regeneration of partial liver grafts is critical for successful living donor liver transplantation (LDLT), especially in adult recipients. The purpose of this study was to investigate the intraoperative hemodynamic changes in partial liver grafts and characterize their potential impact on post-transplant liver regeneration in LDLT.

METHODS

We examined the portal venous flow (PVF) and hepatic arterial flow (HAF) to partial liver grafts by means of ultrasonic transit time flowmeter of donors immediately before graft retrieval and of the corresponding recipients after vascular reconstruction in 48 LDLT cases. We evaluated post-transplant liver regeneration according to the changes in graft liver volume between the time of transplantation and the 7th post-transplant day.

RESULTS

There was a significant increase in PVF to the partial liver grafts in recipients (rPVF) compared with that in donors. In contrast, graft HAF in recipients significantly decreased compared with that in donors. The rPVF inversely correlated with graft weight (GW)-recipient body weight ratio (GRWR), whereas HAF volume showed no significant correlation. The rPVF/GW positively correlated with the rate of liver regeneration (GRR), which inversely correlated with GRWR. The rPVF/GW was significantly higher, and GRR tended to be larger in the small graft group than in the non-small graft group.

CONCLUSIONS

Intraoperative portal hemodynamic changes in partial liver grafts strongly affect their post-transplant regeneration. In particular, in small liver grafts, an immediate and remarkable increase in graft PVF may contribute to rapid liver regeneration after LDLT if the increased PVF remains within a safe range.

The novel BMI-1 inhibitor PTC596 downregulates MCL-1 and induces p53-independent mitochondrial apoptosis in acute myeloid leukemia progenitor cells

Disease recurrence is the major problem in the treatment of acute myeloid leukemia (AML). Relapse is driven by leukemia stem cells, a chemoresistant subpopulation capable of re-establishing disease. Patients with p53 mutant AML are at an extremely high risk of relapse. B-cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) is required for the self-renewal and maintenance of AML stem cells. Here we studied the effects of a novel small molecule inhibitor of BMI-1, PTC596, in AML cells. Treatment with PTC596 reduced MCL-1 expression and triggered several molecular events consistent with induction of mitochondrial apoptosis: loss of mitochondrial membrane potential, BAX conformational change, caspase-3 cleavage and phosphatidylserine externalization. PTC596 induced apoptosis in a p53-independent manner. PTC596 induced apoptosis along with the reduction of MCL-1 and phosphorylated AKT in patient-derived CD34⁺CD38^low/− stem/progenitor cells. Mouse xenograft models demonstrated in vivo anti-leukemia activity of PTC596, which inhibited leukemia cell growth in vivo while sparing normal hematopoietic cells. Our results indicate that PTC596 deserves further evaluation in clinical trials for refractory or relapsed AML patients, especially for those with unfavorable complex karyotype or therapy-related AML that are frequently associated with p53 mutations.

Photoinduced electron transfer in layer-by-layer thin solid films containing cobalt oxide nanosheets, porphyrin, and methyl viologen

The well-known layer-by-layer (LbL) method can be used to prepare solid thin films with a controlled electron transfer direction by appropriately stacking metal oxide nanosheets and functional organic ions. In this study, we prepared thin solid films consisting of cobalt oxide nanosheets (CoNSs) as the electron transfer medium, α,β,γ,δ-tetrakis(1-methylpyridinium-4-yl)porphyrin (TMPyP) as the electron donor, and 1,1'-dimethyl-4,4'-bipyridinium or methyl viologen (MV) as the electron acceptor. We investigated the photoinduced electron transfer phenomenon in these films by irradiating them with 450 nm light. Irradiating the LbL thin solid films prepared with the CoNS/TMPyP/CoNS/MV/CoNS sequence under reduced pressure led to the production of a one-electron reduction compound of MV. Hence, photoinduced electron transfer from TMPyP to MV bound to CoNSs occurred in these LbL thin solid films. However, the conduction band of CoNSs, as determined by the photoabsorption spectral and photoelectrochemical measurements, was much higher than the lowest unoccupied molecular orbital level of TMPyP. Our findings indicate that the observed equipotential photoinduced electron transfer was caused by the metallic electron conductivity of CoNSs, which show a unique charge arrangement of Co³⁺ and Co⁴⁺. Moreover, it was also found that the observed photoinduced charge separation state has a longer life-time (>5 h) under the reduced conditions.

Properties of the feline tumour suppressor reduced expression in immortalized cells (REIC/Dkk-3)

Reduced expression in immortalized cells (REIC/Dkk-3), a member of the human Dickkopf (Dkk) family, is a growth suppressor in human and canine mammary tumours. Mammary gland tumours are common neoplasms with high malignancy in female cats. The purpose of this study was to clone the feline REIC/Dkk-3 homolog, investigate its expression in cell lines established from feline mammary gland tumours, and test its tumour suppressor function. Western blot analysis revealed that expression of the REIC/Dkk-3 protein was reduced in feline mammary carcinoma cell lines. Forced expression of REIC/Dkk-3 induced apoptosis in feline mammary tumour cell lines. These results demonstrate that REIC/Dkk-3 expression, which is downregulated in feline mammary tumour cell lines, results in the induction of apoptosis in these cells. Our findings suggest that feline REIC/Dkk-3 represents a potential molecular target for the development of therapies against feline mammary cancers.

Treatment of Cerebral Aneurysms: Surgical, Endovascular or Combined Intervention

A retrospective study of 437 cases of cerebral aneurysms over a 4 year period is reported. Surgical clipping was performed in 322 cases (254 ruptured and 68 incidental aneurysms) and endovascular embolization was done in 50 cases (26 ruptured and 24 incidental aneurysms). No intervention (either surgical or endovascular) was performed in 65 patients. In the direct surgical treatment group, mortality was 1.5% in incidental and 9.8% in ruptured aneurysms and good recovery was seen in 98.5% and 74.8% cases respectively.

In the endovascular intervention group, results were poor due to the severity of their neurological grading and older age. Mortality was 42.3% in ruptured and 4.2% in incidental aneurysms. Six out of 26 ruptured and 11 out 24 incidental aneurysm patients had complications in the endovascular treatment group. We have discussed the results and indications for both modes of treatment in our study.

Interference Effect between ϕ and Λ(1520) Production Channels in the γp→K^{+}K^{-}p Reaction near Threshold

The ϕ-Λ(1520) interference effect in the γp→K^{+}K^{-}p reaction has been measured for the first time in the energy range from 1.673 to 2.173 GeV. The relative phases between ϕ and Λ(1520) production amplitudes were obtained in the kinematic region where the two resonances overlap. The measurement results support strong constructive interference when K^{+}K^{-} pairs are observed at forward angles but destructive interference for proton emission at forward angles. Furthermore, the observed interference effect does not account for the sqrt[s]=2.1  GeV bump structure in forward differential cross sections for ϕ photoproduction. This fact suggests possible exotic structures such as a hidden-strangeness pentaquark state, a new Pomeron exchange, or rescattering processes via other hyperon states.

Quadrupole Order in the Frustrated Pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y}

A hidden order that emerges in the frustrated pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y} with T_{c}=0.53  K is studied using specific heat, magnetization, and neutron scattering experiments on a high-quality single crystal. Semiquantitative analyses based on a pseudospin-1/2 Hamiltonian for ionic non-Kramers magnetic doublets demonstrate that it is an ordered state of electric quadrupole moments. The elusive spin liquid state of the nominal Tb_{2}Ti_{2}O_{7} is most likely a U(1) quantum spin-liquid state.

Age-related Changes in Energy Intake and Weight in Community-dwelling Middle-aged and Elderly Japanese

OBJECTIVE

This study attempts to describe trends in energy intake and weight change over 12 years according to age at first participation in the study.

DESIGN

Prospective cohort study.

SETTING

The National Institute for Longevity Sciences - Longitudinal Study of Aging (NILS-LSA), a community-based study.

PARTICIPANTS

Participants included 922 men and 879 women who participated in the first study-wave (age 40-79 years) and also participated in at least one study-wave from the second to seventh study-wave. Each study-wave was conducted biennially. For individuals, the entire follow-up period was 12 years.

MEASUREMENTS

Energy intake was calculated from 3-day dietary records with photographs. Weight and height were measured under a fasting state. To estimate linear changes in energy intake and weight over 12 years according to age at first study-wave, we used the mixed-effects model.

RESULTS

Mean (SD) follow-up time and number of study-wave visits were 9.5 (3.7) years and 5.4 (1.8) times, respectively. The fixed effect of the interaction of age and time in energy intake and weight was statistically or marginally statistically significant both in men (p<0.01) and in women (p<0.06). In men, when energy intake was estimated according to age, the rate of decrease in energy intake increased from -6.8 to -33.8 kcal/year for ages 40-79 years. In women, the rate of decrease in energy intake slightly increased in older age groups (-9.1 to -16.7 kcal/year for ages 40-79 years). Weight increased in males in their 40s (0.07 kg/year from age 40) and started to decline by age 53. In women, weight started to decline around age 47 (-0.04 kg/year).

CONCLUSION

Twelve-year longitudinal data showed energy intake declined both in men and women in their 40s, and the rate of decrease increased in older males. Weight started to decline in men in their mid-50s and women in their late 40s. Further studies that focus on energy intake and weight reduction are needed to prevent weight loss or underweight in an increasingly aging society.

First results of the 2.45 GHz Oshima electron cyclotron resonance ion source

A new electron cyclotron resonance ion source has been constructed at Oshima College with a 2.45 GHz magnetron microwave source and permanent magnets employed as the main components. In addition, a solid-state power amplifier with a frequency range of 2.5-6.0 GHz was installed to study two-frequency plasma heating. Three solenoid coils were set up for adjusting the axial magnetic fields. Argon plasma generation and ion beam production have been conducted during the first year of operation. Ion current densities in the ECR plasma were measured using a biased disk. For 2.45 and 4.65 GHz two-frequency plasma heating, the ion density was approximately 1.5 times higher than that of 2.45 GHz single-frequency heating.

Recent developments of ion sources for life-science studies at the Heavy Ion Medical Accelerator in Chiba (invited)

With about 1000-h of relativistic high-energy ion beams provided by Heavy Ion Medical Accelerator in Chiba, about 70 users are performing various biology experiments every year. A rich variety of ion species from hydrogen to xenon ions with a dose rate of several Gy/min is available. Carbon, iron, silicon, helium, neon, argon, hydrogen, and oxygen ions were utilized between 2012 and 2014. Presently, three electron cyclotron resonance ion sources (ECRISs) and one Penning ion source are available. Especially, the two frequency heating techniques have improved the performance of an 18 GHz ECRIS. The results have satisfied most requirements for life-science studies. In addition, this improved performance has realized a feasible solution for similar biology experiments with a hospital-specified accelerator complex.

Two-chamber configuration of Bio-Nano electron cyclotron resonance ion source for fullerene modification

We report on the modification of fullerenes with iron and chlorine using two individually controllable plasmas in the Bio-Nano electron cyclotron resonance ion source (ECRIS). One of the plasmas is composed of fullerene and the other one is composed of iron and chlorine. The online ion beam analysis allows one to investigate the rate of the vapor-phase collisional modification process in the ECRIS, while the offline analyses (e.g., liquid chromatography-mass spectrometry) of the materials deposited on the plasma chamber can give information on the surface-type process. Both analytical methods show the presence of modified fullerenes such as fullerene-chlorine, fullerene-iron, and fullerene-chlorine-iron.