Search for the Majorana Nature of Neutrinos in the Inverted Mass Ordering Region with KamLAND-Zen.

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νßß) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>2.3×10^{26} yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

Precision Analysis of the

We present a precision analysis of the ^{136}Xe two-neutrino ßß electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ßß rate allows us to measure the ratio of the leading and subleading 2νßß nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ßß decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ßß NMEs.

The mechanical properties of the human L4-5 functional spinal unit during cyclic loading. The structural effects of the posterior elements.

Cyclic axial compression-tension tests and cyclic torsional tests were performed on ten fresh human L4-5 functional spinal units to investigate the structural effects of the posterior elements on the mechanical properties of L4-5 functional spinal units. The stiffness of the functional spinal unit increased with the increase of displacement under every loading. This was same in the intact functional spinal units and the functional spinal units after removal of each posterior element, respectively. All the posterior elements contributed to the compressive, tensile, and torsional stiffness of L4-5 functional spinal units. The apophyseal joints had a significant effect on the compressive and torsional stiffness. The effect of the apophyseal joints on the torsional stiffness became greater according to the extent of displacement, whereas their effect on the compressive stiffness was constant. The posterior ligaments (supraspinous and interspinous ligaments) had a significant effect on the tensile stiffness.

Effects of degeneration on the elastic modulus distribution in the lumbar intervertebral disc.

STUDY DESIGN: Local elastic moduli of sliced intervertebral disc specimens were studied after establishing the relation between the elastic modulus and indentation behaviors by model tests using polyurethane specimens. OBJECTIVES: This study presents a method to quantify the distribution of compressive elastic moduli in the lumbar intervertebral disc and to clarify the effects of degeneration on the distribution. SUMMARY OF BACKGROUND DATA: No study has been performed to evaluate the distribution of axial compressive elastic moduli, which is supposed to relate previous biomechanical, biological, and biochemical findings regarding the intervertebral disc. METHODS: Local compressive elastic moduli of the intervertebral disc were estimated by indentation tests. To evaluate the distribution of elastic moduli, indentation tests were performed at nodal points of a 10 mm x 10 mm network on a specimen. Nine cadaveric lumbar discs (L3-L4 and L4-L5) with various degrees of degeneration were tested. The age of subjects ranged 39 to 90 years (mean, 58.4 years). RESULTS: The distribution of elastic moduli in normal discs was symmetric about the midsagittal plane. The mean elastic modulus in the nucleus pulposus was 5.8 kPa and those of the anterior and posterior anulus fibrosus were 110.7 and 75.8 kPa, respectively. The elastic moduli in the lateral portions were the lowest in the normal anulus, and were close to the values of the nucleus. Compared to normal discs, degenerated discs showed irregular distributions of elastic moduli. The elastic moduli of the degenerated nucleus were higher than those in normal discs. CONCLUSIONS: The distribution of elastic moduli is much different between discs with and without degeneration.

The biomechanical effect of postoperative hypolordosis in instrumented lumbar fusion on instrumented and adjacent spinal segments.

STUDY DESIGN: Change in lumbar lordosis was measured in patients that had undergone posterolateral lumbar fusions using transpedicular instrumentation. The biomechanical effects of postoperative lumbar malalignment were measured in cadaveric specimens. OBJECTIVES: To determine the extent of postoperative lumbar sagittal malalignment caused by an intraoperative kneeling position with 90 degrees of hip and knee flexion, and to assess its effect on the mechanical loading of the instrumented and adjacent segments. SUMMARY OF BACKGROUND DATA: The importance of maintaining the baseline lumbar lordosis after surgery has been stressed in the literature. However, there are few objective data to evaluate whether postoperative hypolordosis in the instrumented segments can increase the likelihood of junctional breakdown. METHODS: Segmental lordosis was measured on preoperative standing, intraoperative prone, and postoperative standing radiographs. In human cadaveric spines, a lordosis loss of up to 8 degrees was created across L4-S1 using calibrated transpedicular devices. Specimens were tested in extension and under axial loading in the upright posture. RESULTS: In patients who underwent L4-S1 fusions, the lordosis within the fusion decreased by 10 degrees intraoperatively and after surgery. Postoperative lordosis in the proximal (L2-L3 and L3-L4) segments increased by 2 degrees each, as compared with the preoperative measures. Hypolordosis in the instrumented segments increased the load across the posterior transpedicular devices, the posterior shear force, and the lamina strain at the adjacent level. CONCLUSIONS: Hypolordosis in the instrumented segments caused increased loading of the posterior column of the adjacent segments. These biomechanical effects may explain the degenerative changes at the junctional level that have been observed as long-term consequences of lumbar fusion.

Differential expression of natural killer cell receptors (CD94/NKG2A) on T cells by the stimulation of G-CSF-mobilized peripheral blood mononuclear cells with anti-CD3 monoclonal antibody and cytokines: a study in stem cell donors.

We investigated the expression of the inhibitory NKR (CD94/NKG2A) of the G-CSF mobilized peripheral blood mononuclear cells (G-PBMC) on T cells after stimulation for 7 days by immobilized anti-CD3 monoclonal antibody (mAb) with or without cytokines. We demonstrated increased expression of CD94/NKG2A on CD3+/CD8+ T cells. Also, addition of IL-12 induced significantly more CD94/NKG2A expression than addition of IL-15: CD94+CD3+/NKG2A+CD3+; 43.8 +/- 11.6%/33.7 +/- 11.4% by IL-12 versus 32.8 +/- 13.2%/21.3 +/- 9.6% by IL-15, respectively (n = 9, P < .05). However, >90% purified CD94+ cells CD94+ obtained from IL-15-treated G-PBMC by magnetic cell sorting (MACS) exhibited higher cytolytic (CTL) activity against K562 cells than that from IL-12-treated G-PBMC: E:T = 20:1, 40.7 +/- 18.4% vs 15.1 +/- 5.2% (n = 5, P < .05). Therefore, the cytokine effects on inhibitory NKR expression on T cells and CTL activity are differently regulated. Based on these findings, it may be possible to establish the effective strategy to expand inhibitory NKR-expressing T cells with CTL activity for cell therapy.

A constitutive modeling of the human lumbar intervertebral disc and forward-backward bending simulation.

This paper presents a constitutive law of the lumbar intervertebral disc to be described mathematically with the finite deformation theory. Mechanical behavior of the cadaveric lumbar disc obtained from continuous cyclic compression-tension tests and continuous cyclic axial torsion tests was formulated by the constitutive equation with a semi-circular shaped model. These equations were formulated with or without taking the nucleus pulposus into account. It was also confirmed that forward-backward bending behavior of the disc could be simulated numerically from these equations.

Studies on interactions between traditional herbal and Western medicines. IV: lack of pharmacokinetic interactions between Saiko-ka-ryukotsu-borei-to and carbamazepine in rats.

The possibility of pharmacokinetic interactions between Saiko-ka-ryukotsu-borei-to extract powder (TJ-12), a widely used traditional Chinese herbal (Kampo) medicine, and carbamazepine (CBZ), an important anti-epileptic drug, was examined in rats. There were no significant differences in the serum protein binding of CBZ and carbamazepine- 10,11-epoxide (CBZ-E), its active metabolite, at two concentrations (1 and 10 Bg/ml) between twogroups pretreated orally with the vehicle andTJ-12 suspension (1 g/kg/d, p.o.) for 1 week. One-week repeated pretreatment with TJ- 12 (1 g/kg/d) did not influence liver weight, contents of cytochromes P450 and b5 in hepatic microsomes or the formation rate of CBZ-E from CBZ by its microsomes, while pretreatment with phenobarbital (80 mg/kg/d, i.p.) significantly increased these parameters. Neither a single nor 1-week repeated oral pretreatment with TJ-12 (1 g/kg/d) affected the plasma concentration-time profile and any pharmacokinetic parameter of CBZ or CBZ-E after oral administration of CBZ (50 mg/kg). These results indicated that oral co-administration of TJ-12 with CBZ has no effect ofthe pharmacokinetics of CBZ or CBZ-E in rats. Concomitant treatment with TJ- 12 and CBZ appears to be pharmacokinetically safe in humans.

[Two cases of central nervous system leukemia which responded excellently to intra-arterial injection of ACNU].

Local chemotherapy by intra-arterial administration of ACNU was performed in 2 cases with CNS leukemia, which responded well to this therapy. The first patient was a 42-year-old male who was diagnosed as having chronic myelogenous leukemia with local infiltration of leukemic cells to the optic nerves. By intra-arterial infusion of ACNU (60mg), symptoms and results of ophthalomological examinations were improved remarkably. The second case was a 16-year-old male diagnosed as having acute lymphoblastic leukemia, and complicating with meningeal involvement during the course of chemotherapy. Complete remission was achieved by intra-thecal administration ACNU. Intra-arterial infusion of ACNU would be an effective local chemotherapy of CNS leukemia and its effectiveness could be achieved by less dose of ACNU compared to that of intravenous infusion. Therefore, side effects, e.g., delayed myelosuppression caused by ACNU could be decreased by this method.