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The charge state distributions of krypton (^{86}Kr) with an energy of 2.7 MeV/nucleon were measured using hydrogen (H_{2}) and helium (He) gas charge strippers. A differential pumping system was constructed to confine H_{2} and He gases to a thickness sufficient for the charge state distributions to attain equilibrium. The mean charge states of ^{86}Kr in H_{2} and He gases attained equilibrium at 25.1 and 23.2, respectively, whereas the mean charge state in N_{2} gas at equilibrium was estimated to be less than 20. The charge distributions are successfully reproduced by the cross sections of ionization and electron capture processes optimized by a fitting procedure.

Development of a nondestructive, efficient electric-charge-stripping method is a key requirement for next-generation high-intensity heavy-ion accelerators such as the RIKEN Radioactive-Isotope Beam Factory. A charge stripper employing a low-Z gas is an important candidate applicable to high-intensity uranium beams for replacing carbon-foil strippers. In this study, a high-beam-transmission charge-stripping system employing helium gas for ^{238}U beams injected at 10.8 MeV/u was developed and demonstrated for the first time. The charge-state evolution measured using helium in a thickness range of 0.24–1.83 mg/cm^{2} is compared with theoretical predictions. Energy attenuation and energy spread due to the helium stripper are also investigated.

The charge-state distributions of ^{238}U with energies of 14 and 15 MeV/nucleon were measured using nitrogen (N_{2}) gas and carbon foil (C-foil) charge strippers. The most probable charge states of ^{238}U with energies of 14 and 15 MeV/nucleon in N_{2} gas attain equilibrium at 60.8 and 62.4, whereas those in C-foils attain equilibrium at 75.8 and 76.7, respectively. Novel empirical formulas for the accurate prediction of the equilibrium charge states of ^{238}U with energies 10–20 MeV/nucleon in gases and C-foil were derived by fitting the data in the energy range of 1–20 MeV/nucleon. The charge states predicted by using the formulas for gases and C-foil are in good agreement with the data in the energy range of 10–20 MeV/nucleon within an average of 0.23 and 0.21, respectively.

The RIKEN accelerator complex started feeding the next-generation exotic beam facility radioisotope beam factory (RIBF) with heavy-ion beams from 2007 after the successful commissioning of RIBF at the end of 2006. Many improvements made from 2007 to 2010 were instrumental in increasing the intensity of various heavy-ion beams. However, the available beam intensity of very heavy ion beams, especially uranium beams, is far below our goal of 1 pμA (6×10^{12} particles/s). In order to achieve this goal, upgrade programs are already in progress; the programs include the construction of a new 28-GHz superconducting electron cyclotron resonance ion source and a new injector linac. However, the most serious problem, that of a charge stripper for high-power uranium beams, still remains unsolved, despite extensive research and development work using large foils mounted on a rotating cylinder and a N_{2} gas stripper. A gas stripper is free from problems related to lifetime, though the equilibrium charge state in this stripper is considerably lower than that in a carbon foil, owing to the absence of the density effect. Nevertheless, the merits of gas strippers motivated us to develop a low-Z gas stripper to achieve a higher equilibrium charge state even in gases. We measured the electron-loss and electron-capture cross sections of uranium ions in He gas as a function of their charge state at 11, 14, and 15 MeV/nucleon. The equilibrium charge states extracted from the intersection of the lines of the two cross sections were promisingly higher than those in N_{2} gas by more than 10. Simple simulations of charge development along the stripper thickness were performed by assuming the measured cross sections. The simulation results show that about 1 mg/cm^{2} of He gas should be accumulated to achieve a charge state higher than that of N_{2} gas, notwithstanding the difficulty in accumulation of this helium amount owing to its fast dispersion. However, we now believe that the following two solutions can overcome this difficulty: a gas cell with a very large differential pumping system and a gas cell with a plasma window. Their merits and demerits are discussed in the paper.

The charge-state distributions and equilibrium charge states of uranium (^{238}U) and xenon (^{136}Xe) ions at 11 MeV/nucleon were determined using a gas charge stripper. A differential pumping system facilitated the increase of the nitrogen gas thickness up to 1.3 mg/cm^{2}, which is sufficient for the most probable charge state to attain equilibrium. The charge states of ^{238}U attain equilibrium at 56.0, 56.6, and 55.7 in N_{2}, Ar, and CO_{2} media with thicknesses of 125, 79, and 126 μg/cm^{2}, respectively, while those of ^{136}Xe attain equilibrium at 40.5, 40.1, and 40.3 in N_{2}, Ar, and CO_{2} media with thicknesses of 163, 95, and 139 μg/cm^{2}, respectively. The equilibrium charge states of ^{136}Xe are acceptable for acceleration by the subsequent cyclotron. The measured data of ^{238}U were used to devise an empirical formula for the prediction of the equilibrium charge state in gaseous media over the energy region of 0.01–60 MeV/nucleon. The equilibrium charge state of ^{136}Xe as predicted by the devised formula is in good agreement with the data.

Objective: To determine whether Aquacel Ag Hydrofiber dressings containing ionic silver are superior to film dressings for preventing superficial surgical site infections (SSI) in patients undergoing elective gastrointestinal surgery., Background: Multiple clinical trials have assessed the effectiveness of silver-containing wound dressings; however, systematic reviews failed to find any advantages of these dressings and concluded that there was insufficient evidence to indicate that they prevented wound infections. This study aimed to evaluate the efficacy of Aquacel Ag Hydrofiber dressings for preventing superficial SSIs in patients undergoing gastrointestinal surgery., Methods: Patients undergoing elective gastrointestinal surgery were randomly assigned to receive either Aquacel Ag Hydrofiber (study group) or film dressings (control group). The primary end point was superficial SSI within 30 days after surgery (UMIN Clinical Trials Registry ID: 000043081)., Results: A total of 865 patients (427 study group, 438 control group) were qualified for primary end-point analysis. The overall rate of superficial SSIs was significantly lower in the study group than in the control group (6.8% vs 11.4%, P = 0.019). There was no significant difference in superficial SSI rates between the groups in patients undergoing upper gastrointestinal surgery; however, the rate was significantly lower in the study group in patients undergoing lower gastrointestinal surgery ( P = 0.042). Multivariate analysis identified Aquacel Ag Hydrofiber dressings as an independent factor for reducing superficial SSIs (odds ratio, 0.602; 95% confidence interval, 0.367-0.986; P = 0.044)., Conclusions: Aquacel Ag Hydrofiber dressings can reduce superficial SSIs compared to film dressings in patients undergoing elective gastrointestinal surgery, especially lower gastrointestinal surgery., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

A 38-year-old woman was admitted to our hospital due to severe anemia. CT showed a 13×12 cm tumor with moderately enhanced wall thickening in the right upper abdomen. The huge tumor located adjacent to the jejunum and compressed the right transverse colon. Hemorrhagic necrosis and air were observed within the tumor, suspecting tumor penetration into the jejunum. The patient was diagnosed with abdominal GIST with jejunal infiltration. Laparotomy revealed a 13× 11 cm solid mass with intra-tumoral hemorrhage and invasion into the jejunum, located in the transverse mesocolon. Tumor resection combined with partial jejunectomy and transverse colectomy were performed. Immunohistochemical findings of the resected specimen was positive for c-kit and DOG-1, and the MIB-1 positive rate was 10%. Three weeks after the operation, re-anastomosis was performed due to transverse colon anastomotic stricture. She was discharged 45 days after first operation. Currently, 9 months after the operation, patient has been prescribed imatinib and is alive without recurrence.

We demonstrate radio-over-fiber (RoF) transmission with a 10-W feed power-over-fiber (PWoF) using a conventional multimode fiber (MMF). In this scheme, the modal dispersion and feed light crosstalk in the MMF are effectively mitigated by the combination of center-launching (CL) and offset-launching (OL) techniques. The CL is used for propagating the feed light into lower-order modes in the MMF, while the OL is used not only for propagating the optical data signals into higher-order modes in the MMF, but also for mitigating the modal dispersion. We successfully achieved significant improvement in the RoF transmission performance with the 10-W feed PWoF and extended the link length up to 4 km, owing to the two techniques.

The double-differential cross sections for the 48Ca(p,n) and 48Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) components. The integrated GT strengths up to an excitation energy of 30 MeV in 48Sc are 15.3+/-2.2 and 2.8+/-0.3 in the (p,n) and (n,p) spectra, respectively. In the (n,p) spectra additional GT strengths were found above 8 MeV where shell models within the fp shell-model space predict almost no GT strengths, suggesting that the present shell-model description of the nuclear matrix element of the two-neutrino double-beta decay is incomplete.

We evaluated the effects of a casein hydrolysate (CH) prepared from Aspergillus oryzae protease on rat adjuvant arthritis, a model of human rheumatoid arthritis. CH was administered orally once a day to the animals for 22 d after the adjuvant injection. CH suppressed swelling in the adjuvant-uninjected hind paws, and a higher dose of CH suppressed the increase in arthritic score and swelling of the adjuvant-injected hind paws. A histopathological examination revealed evidence that the higher dose of CH suppressed the articular changes in the rats. In addition, CH suppressed the production of nitric oxide and prostaglandin E(2) in the plasma of the rats. These results suggest that CH had a suppressive effect on adjuvant arthritis by inhibiting the acute and chronic inflammatory reactions.

Lactobacillus casei I-5 isolated from an alcohol fermentation broth enhanced immunity and prevented pathogenic infection as a probiotic. Mice fed with I-5 cells for 11 days prior to an intraperitoneal challenge with pathogenic Escherichia coli Juhl exhibited a high survival rate compared with the control group. Rats fed with I-5 cells for 10 days significantly increased the phagocytosis of peritoneal macrophages. In a cell culture system employing peritoneal macrophages from rats, the I-5 administration activated NF-kappaB stimulated by LPS. It also enhanced LPS-stimulated IL-12 and TNF-alpha production, but not IL-6 production. These results show that L. casei I-5 effectively prevented infection by pathogenic E. coli possibly through the activation of peritoneal macrophages. The strain would be useful to prevent pathogenic microbial infections in humans and farm animals.

We report the results of the first-time test of the local hidden variable theories (Bell-Clauser-Horne-Shimony-Holt) involving strongly interacting pairs of massive spin 1/2 hadrons from the decay of short-lived (tau<10;-21sec) 2He spin-singlet state, populated in the nuclear reaction 2H+;1H-->;2He+n. The novel features of this experiment are (a) the use of an 'event-ready' [corrected] detector of nearly 100% efficiency to prepare an unbiased sample and (b) a focal-plane polarimeter of full 2pi sr acceptance with a random "post selection" of the reference axes. The spin-correlation function is deduced to be S[exp](pi/4)=2.83+/-0.24stat+/-0.07sys. This result is in agreement with nonlocal quantum mechanical prediction and it violates the Bell-CHSH inequality of |S|

Three precise measurements for elastic pd scattering at 135 MeV/A have been performed with the three different experimental setups. The cross sections are described well by the theoretical predictions based on modern nucleon-nucleon forces combined with three-nucleon forces. Relativistic Faddeev calculations show that relativistic effects are restricted to backward angles. This result supports the two measurements recently reported by RIKEN and contradicts the KVI data.

In order to elucidate the mechanism of the antihypertensive action of dried bonito (katsuobushi), we compared the effects of dried bonito extracts with those of captopril, an angiotensin I-converting enzyme (ACE) inhibitor, on aorta preparations isolated from rats. Dried bonito extracts (3 x 10(-4) to 3 x 10(-3) g/ml) more potently relaxed contractions induced by norepinephrine (10(-7) M) than contractions induced by KCl (55.9 mM). Dried bonito extracts (3 x 10(-3) g/ml) slightly inhibited 10(-7) M angiotensin I-induced contractions. In contrast, captopril (10(-8) to 10(-7) M) did not affect 10(-7) M norepinephrine- or 55.9 mM KCl-induced contractions, but a higher concentration of captopril (10(-6) M) very slightly relaxed it. Captopril (10(-8) to 10(-6) M) markedly inhibited 10(-7) M angiotensin I-induced contractions in a concentration-dependent manner. These results suggest that antihypertensive mechanism of action induced by dried bonito involves direct action on vascular smooth muscle in addition to ACE-inhibitory activity.

Lactic acid bacteria were isolated from an alcohol fermentation broth, and the activity as a probiotic was examined using pathogenic E. coli. Thirty-six strains exhibiting good growth were isolated in the medium of concentrated mush which was a residue resulted in the alcohol distillation process. One of these strains, Lactobacillus paracasei subsp. paracasei I-5, could be grown in the medium containing 8 vol% ethanol and at 45 degrees C. The characteristics were different from the type strain, L. paracasei subsp. paracasei NBRC 15889. L. paracasei I-5 showed an excellent growth in the concentrated mush, which just diluted two-fold and adjusted the pH. ICR mice were fed with a standard germ-free feed (CMF) and the strain I-5 (7 x 10(9) cells/day) was orally administrated for 11 days prior to the intraperitoneal challenge with pathogenic E. coli Juhl. After the challenge, mice administrated the strain I-5 exhibited a high survival rate and survival extension days (p < 0.01) compared with the control. The results suggested that the strain might enhance the animal resistance against microbial pathogens. Neonatal diarrhea caused by E. coli is a serious disease in calf breeding. The strain might be practically valuable to prevent diarrhea in calves.

alpha-Linked galactooligosaccharide (alpha-GOS) has been reported to change the composition of enteric microflora. In the present study, the antiarthritic effect of alpha-GOS was evaluated by employing adjuvant-induced arthritis (AIA) in Wistar rats and type II collagen-induced arthritis (CIA) in DBA/1J mice. The animals were given alpha-GOS orally. This substance had beneficial effects on both clinical signs, such as erythema and swelling of the limbs, and histopathological findings in the hind paw joints in a dose-dependent manner. alpha-GOS reduced the plasma nitrite/nitrate (NOx) level in rats with AIA. In the cell culture system employing peritoneal macrophages from rats with AIA, alpha-GOS enhanced interleukin-1 production without lipopolysaccharide stimulation in a dose-dependent manner, suggesting that alpha-GOS stimulates peritoneal macrophages through modulation of enteric microflora. Since alpha-GOS modulates the composition of the enteric microflora, the antiarthritic effects of alpha-GOS could be partly attributable to its immunomodulating activity. Thus, alpha-GOS is a potential functional food for the treatment of human rheumatoid arthritis.

To enhance the stability in vivo, new derivatives of cytogenin were synthesized, and their biological activity and stability in mice were estimated. 2-(8-Hydroxy-6-methoxy-1-oxo-1H-2-benzopyran-3-yl)propionic acid (NM-3) was found to be the most stable among them. It modified collagen-induced arthritis in mice. It also showed potent anti-angiogenic activity in a mouse dorsal air sac assay.

Cytogenin (8-hydroxy-3-hydroxymethyl-6-methoxyisocoumarin) is a new microbial product with antitumor and antirheumatoid arthritis effects in vivo when administered orally, although its mechanism(s) of action is not known well. Both neoplasia and rheumatoid arthritis are referred to as angiogenesis-dependent diseases. The aim of the present study was to investigate the effects of cytogenin on both physiological and pathological angiogenesis, using the growing chick embryo chorioallantoic membrane and mouse dorsal air sac assay systems, respectively. The microbial product at doses up to 100 micrograms/egg did not significantly affect embryonic angiogenesis when topically placed on the surface of the chorioallantoic membrane, suggesting that it has no effect on the physiological (or normal) angiogenic response. By contrast, systemic administration of cytogenin (100 mg/kg p.o., for 5 consecutive days) significantly suppressed angiogenesis induced by malignant tumor cells (S-180), one of pathological neovascularization, in a mouse dorsal air sac assay system. Pharmacokinetic studies in mice revealed that the maximal concentration of cytogenin in plasma after a single 100 mg/kg oral dose of the compound was 32 microM. In vitro experiments involving cultured vascular endothelial cells showed that cytogenin at concentrations determined by pharmacokinetic study, had little effect on plasminogen activator secretion, tube formation and the proliferation of endothelial cells. These results suggest that cytogenin is a novel oral antiangiogenic agent, that the mechanism of its antiangiogenic action contributes to its suppressive effects on both tumor growth and rheumatoid arthritis that we previously found, and that it could be developed as a potential therapeutic agent for cancer, rheumatoid arthritis and other angiogenesis-dependent disorders such as diabetic retinopathy.

To improve the efficiency of hepatic intra-arterial (h.i.a.) chemotherapy, we selected pirarubicin (THP) because it shows good properties for h.i.a. chemotherapy, such as fast and efficient cellular uptake, and used it for h.i.a. chemotherapy in rabbits with V x 2 tumour implanted in the liver. The anti-tumour effect of THP upon h.i.a. administration was compared with that upon intravenous (i.v.) injection and also with the anti-tumour activity of epirubicin (EPI) upon h.i.a. injection using optimal and maximal tolerated doses of each drug. When tumour growth rates and morphometric examinations were evaluated, it was found that THP and EPI were effective against V x 2 tumour when injected via the h.i.a. route. The activity of THP was stronger than that of EPI. As regards h.i.a. injection-related complication, plasma transaminase levels were temporarily elevated. To demonstrate higher anti-tumour activity and other advantages of h.i.a. injection of THP, plasma and tumour drug concentrations were determined by high-performance liquid chromatography after THP or EPI was administered at an equal dose to the rabbit V x 2 model. Hepatic intra-arterial injection of THP accomplished a selective and higher uptake into the tumour and lower effusion into the plasma than i.v. injection of THP or h.i.a. injection of EPL. Our findings indicate that THP is the better candidate of the two drugs tested for the h.i.a. chemotherapy because of its greater anti-tumour activity and the lower systemic drug exposure achieved upon h.i.a. injection.