Search for the invisible decay of neutrons with KamLAND.

The Kamioka Liquid scintillator Anti-Neutrino Detector is used in a search for single neutron or two-neutron intranuclear disappearance that would produce holes in the -shell energy level of (12)C nuclei. Such holes could be created as a result of nucleon decay into invisible modes (inv), e.g., n--> 3v or nn--> 2v. The deexcitation of the corresponding daughter nucleus results in a sequence of space and time-correlated events observable in the liquid scintillator detector. We report on new limits for one- and two-neutron disappearance: tau(n--> inv) > 5.8 x 10(29) years and tau (nn--> inv) > 1.4 x 10(30) years at 90% C.L. These results represent an improvement of factors of approximately 3 and >10(4) and over previous experiments.

Experimental investigation of geologically produced antineutrinos with KamLAND.

The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth. Here we present results from a search for geoneutrinos with KamLAND. Assuming a Th/U mass concentration ratio of 3.9, the 90 per cent confidence interval for the total number of geoneutrinos detected is 4.5 to 54.2. This result is consistent with the central value of 19 predicted by geophysical models. Although our present data have limited statistical power, they nevertheless provide by direct means an upper limit (60 TW) for the radiogenic power of U and Th in the Earth, a quantity that is currently poorly constrained.

Measurement of neutrino oscillation with KamLAND: evidence of spectral distortion.

We present results of a study of neutrino oscillation based on a 766 ton/year exposure of KamLAND to reactor antineutrinos. We observe 258 nu (e) candidate events with energies above 3.4 MeV compared to 365.2+/-23.7 events expected in the absence of neutrino oscillation. Accounting for 17.8+/-7.3 expected background events, the statistical significance for reactor nu (e) disappearance is 99.998%. The observed energy spectrum disagrees with the expected spectral shape in the absence of neutrino oscillation at 99.6% significance and prefers the distortion expected from nu (e) oscillation effects. A two-neutrino oscillation analysis of the KamLAND data gives Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2). A global analysis of data from KamLAND and solar-neutrino experiments yields Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2) and tan((2)theta=0.40(+0.10)(-0.07), the most precise determination to date.

High sensitivity search for nu;e's from the sun and other sources at KamLAND.

Data corresponding to a KamLAND detector exposure of 0.28 kton yr has been used to search for nu;(e)'s in the energy range 8.3

Computed tomography of odontogenic myxoma.

OBJECTIVES: The purpose of this study was to clarify the CT features of odontogenic myxoma. METHODS: CT appearances were analysed in 17 patients with histologically verified odontogenic myxoma collected from five dental hospitals in Japan. RESULTS: On the CT images, tumour borders were generally well defined with a smooth margin both for bony and soft tissue structures in all patients. Cortical status was clearly evaluated using CT and the continuity was interrupted in nine patients. Intralesional trabeculations were observed in 13 patients. Of these 13, 6 patients showed the characteristic appearance of angular or straight trabeculations within the tumour. The trabeculations were frequently observed at the peripheral portion of the tumour. In three maxillary tumours, soft tissue margins were observed beyond the cortical margin and/or intralesional trabeculations. In 10 of the 13 lesions evaluated, the majority of the whole tumour area showed relatively lower density compared with surrounding muscles. CONCLUSION: CT clearly demonstrated characteristic features of odontogenic myxoma. CT analysis may contribute to establishing a consensus regarding the interpretation of conventional radiographic appearances in odontogenic myxoma.

First results from KamLAND: evidence for reactor antineutrino disappearance.

KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded.

Declining trend in the in-hospital case-fatality rate from acute myocardial infarction in Miyagi Prefecture from 1980 to 1999.

The case-fatality rate from acute myocardial infarction (AMI) appears to have been declining in recent decades, so the present study reviewed the trend in in-hospital case-fatalities from AMI in Miyagi Prefecture, Japan, 1980-1999. The causes of death and the effects of gender and age on the trend were also analyzed. From the AMI registration database of the Miyagi Study Group for AMI, 12,961 cases of AMI were analyzed. The 30-day in-hospital case-fatality was calculated from the data for 1980-1999: data for causes of death were available for 1980-1997, and the data concerning primary percutaneous transluminal coronary angioplasty (PTCA) for AMI were available for 1997-1999. The in-hospital case-fatality rate declined from 17.0% in the early 80s to 7.3% in the late 90s (approximately 57% reduction). The in-hospital case-fatality rate was higher in female patients. Rhythm failure substantially decreased in the late 1980s. Pump failure is decreasing, but is still the biggest problem. The in-hospital case-fatality rate was significantly lower in patients received PTCA. The declining trend in the in-hospital case-fatality rate suggests the benefits of current therapeutic procedures, including primary PTCA, for AMI. Pump failure is an important target for further decreasing the trend.

Regulation of Th2 cell differentiation by mel-18, a mammalian polycomb group gene.

Polycomb group (PcG) gene products regulate homeobox gene expression in Drosophila and vertebrates and also cell cycle progression of immature lymphocytes. In a gene-disrupted mouse for polycomb group gene mel-18, mature peripheral T cells exhibited normal anti-TCR-induced proliferation; however, the production of Th2 cytokines (IL-4, IL-5, and IL-13) was significantly reduced, whereas production of IFNgamma was modestly enhanced. Th2 cell differentiation was impaired, and the defect was associated with decreased levels in demethylation of the IL-4 gene. Significantly, reduced GATA3 induction was demonstrated. In vivo antigen-induced IgG1 production and Nippostrongylus brasiliensis-induced eosinophilia were significantly affected, reflecting the deficit in Th2 cell differentiation. Thus, the PcG gene products play a critical role in the control of Th2 cell differentiation and Th2-dependent immune responses.

Microvolt T wave alternans in human cardiac hypertrophy: electrical instability and abnormal myocardial arrangement.

INTRODUCTION: Although T wave alternans (TWA) is a promising risk marker for myocardial electrical instability, it remains unclear how the presence of TWA is related to myocardial damage. METHODS AND RESULTS: TWA was measured in 28 patients with hypertrophic cardiomyopathy (HCM), 29 patients with hypertensive left ventricular hypertrophy (HLVH), and 15 normal volunteers using a CH2000 system. The amplitude of TWA (Valt) was measured at the lead with the maximum amplitude. Cardiac biopsy was performed in 12 HCM patients, who were divided into two groups (severe and mild) based on histologic findings of myocardial disarray and fibrosis. TWA was positive (Valt > 1.9 microV) in 61% of HCM and 31% of HLVH, despite a nearly identical left ventricular mass index (176 +/- 65 g/m2 vs 175 +/- 39 g/m2). Valt at heart rate = 110 beats/min was significantly greater in HCM with severe disarray and fibrosis than in HCM with mild disarray and in HLVH. CONCLUSION: In HCM patients, a positive TWA test probably is related to abnormal myocardial arrangement (disarray) and/or fibrosis, and it may reflect electrical instability of the myocardium.

Inductive signals from the somatopleure mediated by bone morphogenetic proteins are essential for the formation of the sternal component of avian ribs.

The posterior five pairs of avian ribs are composed of vertebral and sternal components, both derived from the somitic mesoderm. For the patterning of the rib cartilage, inductive signals from neighboring tissues on the somitic mesoderm have been suggested to play critical roles. The notochord and surface ectoderm overlying the somitic mesoderm are essentially required for the development of proximal and distal regions of the ribs, respectively. Involvement of the somatopleure in rib development has already been suggested but is less understood than those of the notochord and surface ectoderm. In this study, we reinvestigated the role of the somatopleure during rib development. We first identified the chicken homologue of the mouse Mesenchymal forkhead-1 (cMfh-1) gene based on sequence similarities. cMfh-1 was observed to be expressed in the nonaxial mesoderm, including the somitic mesoderm, and, subsequently, in cartilage forming the ribs, vertebrae, and appendicular skeletal system. In the interlimb region, corresponding to somites 21-25 (or 26), cMfh-1-positive somitic mesoderm was seen penetrating the somatopleure of E4 embryos, and cMfh-1 was used as a molecular marker demarcating prospective rib cartilage. A series of experiments affecting the penetration of the somitic mesoderm into the somatopleure was performed in the present study, resulting in defects in sternal rib formation. The inductive signals emanating from the somatopleure mediated by BMP family proteins were observed to be essentially involved in the ingrowth of the somitic mesoderm. BMP4 alone, however, could not completely replace inductive signals from the somatopleure, suggesting the involvement of additional signals for rib formation.

A novel single-nucleotide polymorphism at the 5'-flanking region of SAA1 associated with risk of type AA amyloidosis secondary to rheumatoid arthritis.

OBJECTIVE: To address whether the gamma haplotype at exon 3 of the SAA1 gene is directly associated with type AA amyloidosis or is merely in linkage with an unknown polymorphism that is primarily associated with disease risk, we examined the SAA1 gene for new polymorphisms. METHODS: We analyzed DNA samples from 44 rheumatoid arthritis (RA) patients with AA amyloidosis (amyloid group), 55 RA patients without AA amyloidosis (RA group), and 58 non-RA healthy subjects (non-RA group). We also examined DNA samples from 50 Caucasians to compare linkage disequilibrium relationships involving SAA1 region polymorphisms between Japanese and Caucasoid populations. RESULTS: We observed 3 novel single-nucleotide polymorphisms (SNPs) in the 5'-flanking region of SAA1: -61C/G, -13T/C, and -2G/A. Comparison of allele frequencies and ratios of individuals with particular alleles between the study groups revealed statistically significant differences between the amyloid and RA groups and between the amyloid and non-RA groups. Statistical analysis revealed that the -13T/C SNP was strongly associated with AA amyloidosis. In addition, we found tight linkage between the -13T allele and the alpha haplotype, rather than the beta haplotype, at exon 3 in the Caucasoid population, while -13T was closely linked to the gamma and beta haplotypes, rather than the alpha haplotype, in the Japanese population. Since the linkage disequilibrium relationship was reversed between the Japanese and Caucasoid populations, different exon 3 haplotypes of SAA1 are found to be associated with the risk of AA amyloidosis in different ethnic groups. CONCLUSION: Our data suggest that the SAA1 -13T allele, rather than SAA1 exon 3 haplotypes, is primarily associated with AA amyloidosis risk.

Mice doubly deficient for the Polycomb Group genes Mel18 and Bmi1 reveal synergy and requirement for maintenance but not initiation of Hox gene expression.

Polycomb group genes were identified as a conserved group of genes whose products are required in multimeric complexes to maintain spatially restricted expression of Hox cluster genes. Unlike in Drosophila, in mammals Polycomb group (PcG) genes are represented as highly related gene pairs, indicative of duplication during metazoan evolution. Mel18 and Bmi1 are mammalian homologs of Drosophila Posterior sex combs. Mice deficient for Mel18 or Bmi1 exhibit similar posterior transformations of the axial skeleton and display severe immune deficiency, suggesting that their gene products act on overlapping pathways/target genes. However unique phenotypes upon loss of either Mel18 or Bmi1 are also observed. We show using embryos doubly deficient for Mel18 and Bmi1 that Mel18 and Bmi1 act in synergy and in a dose-dependent and cell type-specific manner to repress Hox cluster genes and mediate cell survival of embryos during development. In addition, we demonstrate that Mel18 and Bmi1, although essential for maintenance of the appropriate expression domains of Hox cluster genes, are not required for the initial establishment of Hox gene expression. Furthermore, we show an unexpected requirement for Mel18 and Bmi1 gene products to maintain stable expression of Hox cluster genes in regions caudal to the prospective anterior expression boundaries during subsequent development.

A prospective study of renal disease in patients with early rheumatoid arthritis.

OBJECTIVES: This prospective study was designed to clarify the frequency, causes, and clinical course of renal disease in patients with early rheumatoid arthritis (RA). METHODS: 235 patients (185 women, mean age 49.4 years) with early RA of less than one year's duration were enrolled and assessed monthly. Proteinuria was defined as a positive dipstick result and microscopic haematuria was defined as the presence of > or =5 red blood cells per high power field. Urinary abnormalities lasting three months or longer were defined as persistent abnormalities. RESULTS: At entry, 40 patients exhibited haematuria, two had a raised serum creatinine concentration, and none had proteinuria. During the observation period (average 42 months), persistent haematuria was found in 43, persistent proteinuria in 17, and a raised serum creatinine concentration in 14 patients. Persistent proteinuria was caused by drugs in 14 of 17 patients and disappeared in most cases. Risk factors for drug induced proteinuria included a raised C reactive protein and erythrocyte sedimentation rate and age over 50 at entry. Drugs resulted in a raised serum creatinine concentration in eight of 14 patients. The incidence of haematuria at entry did not differ among patients who had been treated with non-steroidal anti-inflammatory drugs, disease modifying antirheumatic drugs, or no drugs. In some patients with isolated haematuria, the haematuria appeared when the activity of RA was high and resolved when it was low. CONCLUSIONS: This study suggests that a raised serum creatinine concentration or persistent proteinuria in patients with early RA is predominantly drug related whereas, in contrast, isolated haematuria is more directly associated with the activity of the disease process.

Antiphospholipid syndrome with complete abdominal aorta occlusion and chondritis.

Abstract We report a case of a 42-year-old man with antiphospholipid syndrome (APS) with chondritis. He presented with preceding insidious progressive occlusion of the bilateral common iliac arteries extending to the lower two-thirds of the abdominal aorta. Active thrombotic events developed concurrent with the onset of chondritis, and resulted in massive thromboses in multiple organs and renal dysfunction. Both conditions responded well to combined intravenous high-dose methylprednisolone and anticoagulation therapy. The inflammatory component of his disease may have played a major role in the pathogenesis of thrombosis given the concurrent active inflammation from his chondritis.

Rationale for intralesional valrubicin in chemoradiation of squamous cell carcinoma of the head and neck.

OBJECTIVES/HYPOTHESIS: With some advanced squamous cell carcinomas (SCCs) of the head and neck, chemoradiation therapy may obviate the need for surgical intervention. However, both modalities are known to produce organ toxicities, and tumor insensitivity remains problematic. Thus there is a clear need for the development of new treatment strategies. Accordingly, preclinical studies to evaluate the use of valrubicin, a contact-safe, mechanistically novel antitumor agent, combined with low-dose radiation for the therapy of SCC have been conducted. METHODS: The comparative in vitro antitumor activities of valrubicin with or without irradiation versus cisplatin were evaluated using human-derived sensitive and cisplatin-resistant SCC cell lines. A hamster cheek pouch model of SCC was used to assess the efficacy of weekly intratumoral valrubicin injections with and without concurrent low-dose irradiation. RESULTS: Valrubicin cytotoxicity was found to be comparable in both sensitive and platinum-resistant cell lines and superior to cisplatin. The addition of minimally cytotoxic cell irradiation (300-450 cGy) resulted in prolonged G2/M cell cycle arrest and a supraadditive increase in apoptotic cell death. In hamsters, once a week x 3 intratumoral drug injections (3, 6, or 9 mg) were growth inhibitory; however, when valrubicin (6 mg) was combined with minimally cytotoxic irradiation (150, 250, or 350 cGy) significant tumor shrinkage was observed. CONCLUSIONS: Valrubicin produces supra-additive effects against SCC when combined with low-dose irradiation. This effect appears to correlate with the ability of valrubicin, a cytoplasmic-localizing drug, to inhibit protein kinase C. Therapeutic use of valrubicin against SCC could provide for reduced radiation doses with consequent improved efficacy and reduction in host toxicity.

Catalytic inhibition of DNA topoisomerase II by N-benzyladriamycin (AD 288).

N-Benzyladriamycin (AD 288) is a highly lipophilic, semi-synthetic congener of doxorubicin (DOX). Unlike DOX, which stimulates double-stranded DNA scission by stabilizing topoisomerase II/DNA cleavable complexes, AD 288 is a catalytic inhibitor of topoisomerase II, capable of preventing topoisomerase II activity on DNA. The concentration of AD 288 required to inhibit the topoisomerase II-catalyzed decatenation of linked networks of kinetoplast DNA was comparable to that for DOX. However, AD 288 did not stabilize cleavable complex formation or stimulate topoisomerase II-mediated DNA cleavage. In addition, AD 288 inhibited the formation of cleavable complexes by etoposide in a concentration-dependent manner. Human CCRF-CEM cells and murine J774. 2 cells exhibiting resistance against DOX, teniposide, or 3'-hydroxy-3'-deaminodoxorubicin through reduced topoisomerase II activity remained sensitive to AD 288. These studies suggest that AD 288 inhibits topoisomerase II activity by preventing the initial non-covalent binding of topoisomerase II to DNA. Since AD 288 is a potent DNA intercalator, catalytic inhibition is achieved by prohibiting access of the enzyme to DNA binding sites. These results also demonstrate that specific substitutions on the aminosugar of DOX can alter the mechanism of topoisomerase II inhibition.

Long-term right ventricular volume overload increases myocardial fluorodeoxyglucose uptake in the interventricular septum in patients with atrial septal defect.

BACKGROUND: Several studies have shown that long-term right ventricular (RV) overload in animal models alters myocardial energy substrate metabolism. However, whether long-term RV volume overload alters this metabolism in the human is unclear. METHODS AND RESULTS: We performed positron emission tomography with [(18)F]fluorodeoxyglucose (FDG) and single-photon emission tomography (SPECT) with [(201)Tl]TlCl (Tl) and [(123)I]15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) in 11 patients with atrial septal defect (ASD) and 11 control subjects. In the FDG study, we calculated myocardial metabolic rate of glucose (MMR) in interventricular septum (IVS) and left ventricular (LV) free wall. MMR was significantly increased in IVS compared with LV free wall in the ASD patients (420+/-35 versus 333+/-32 mol x kg(-1) x min(-1); P<0.05) but not in the control group (347+/-27 versus 357+/-25 mol x kg(-1) x min(-1)). In both ASD and control groups, SPECT count was not significantly different between IVS and LV free wall in Tl (ASD, 160+/-11 versus 177+/-12; control, 141+/-12 versus 157+/-14 counts per 15 minutes) and BMIPP studies (ASD, 203+/-14 versus 212+/-18; control, 162+/-16 versus 176+/-16 counts per 15 minutes). MMR in the IVS/LV free wall ratio in the ASD group significantly correlated with indices related to RV volume overload. CONCLUSIONS: Given the assumption that long-term RV volume overload did not affect the lumped constant, the present study suggests that, unlike myocardial perfusion or fatty acid analogue uptake, myocardial glucose utilization in IVS relative to LV free wall is increased in relation to long-term RV volume overload in patients with ASD.

Changes of the thromboxane A2/prostacyclin balance in the urine of patients with renal diseases analyzed by gas chromatography/selected ion monitoring.

The thromboxane A2/prostacyclin (TX/PGI) ratios were measured in patients with renal diseases to elucidate the relationship between the ratios and the pathological changes of the diseases. Urinary stable metabolites of thromboxane A2 and prostacyclin, 11-dehydro-thromboxane B2 and 2,3-dinor-6-keto-prostaglandin F1alpha, respectively, were converted to 1-methyl ester-propylamide-9,12,15-tris-dimethylisopropylsilyl ether derivative and 1-methyl ester-6-methoxime-9,12,15-tris-dimethylisopropylsilyl ether derivative, respectively, and applied to a gas chromatography/selected ion monitoring. The TX/PGI ratios of 10 outpatients and 6 inpatients with chronic glomerulonephritis were higher than those of 13 healthy volunteers. In an inpatient with systemic lupus erythematoides, the TX/PGI ratios were gradually lowered to the normal level with the therapies. Furthermore, the ratios seemed to change in advance of the changes of the levels of urinary protein and hematuria. These observations suggested that the TX/PGI ratio was a useful index to assess the pathological condition of renal diseases and the effects of treatment.

Renal function estimated from serum creatinine is overestimated in patients with rheumatoid arthritis because of their muscle atrophy.

Abstract We evaluated the reliability of serum creatinine concentration (Scr) to estimate renal function in patients with rheumatoid arthritis (RA). To quantify muscle volume (study 1) the lean body mass (LBM) in 25 women RA patients and 10 controls was measured using dual X-ray absorptiometry (DEXA). The 60-min creatinine clearance (Ccr60) and 60-min urinary excretion of creatinine (Ucr60) were also determined. The Ucr60 and LBM of the extremities, which were significantly correlated (r = 0.757, P < 0.0001), were lower in patients with long-standing and advanced RA than in controls. In study 2, the 24-h creatinine clearance (Ccr24) and 24-h urinary excretion of creatinine (Ucr24) were determined retrospectively in 82 women RA patients and 120 controls with normal Scr. The Ccr of long-standing and advanced RA patients was significantly lower than that of the controls, although the Scr of the long-standing RA patients was significantly lower than that of the advanced RA patients. The upper limit of the normal Scr for RA patients was calculated as being approximately 10% lower than that for controls. Thus, the renal function estimated from Scr may be overestimated in patients with long-standing and advanced RA because of their muscle atrophy.