K/pi Fluctuations at relativistic energies

We report K/pi fluctuations from Au + Au collisions at sqrt[s(NN)]= 19.6, 62.4, 130, and 200 GeV using the STAR detector at the Relativistic Heavy Ion Collider. K/pi fluctuations in central collisions show little dependence on incident energy and are on the same order as those from NA49 at the Super Proton Synchrotron in central Pb + Pb collisions at sqrt[s(NN)]=12.3 and 17.3 GeV. We report results for the collision centrality dependence of K/pi fluctuations and results for charge-separated fluctuations. We observe that the K/pi fluctuations scale with the charged particle multiplicity density.

Effects of carotenoids from Deinococcus radiodurans on protein oxidation

AIMS

To evaluate the antioxidant effect of carotenoids from Deinococcus radiodurans on protein.

METHODS AND RESULTS

Deinococcus radiodurans strain R1 (ATCC 13939) and its mutant strain R1DeltacrtB were used for this study. The total carotenoids (R1ex) from D. radiodurans were obtained by extraction with acetone/methanol (7 : 2, by vol), and their antioxidant activity was measured using the DPPH (2,2-diphenyl-1-picrylhydrazyl) system. The protein oxidation level, in vitro and in the cell, was measured using the DNPH (2,4-dinitrophenyl hydrazine) method. The carotenoid extract R1ex scavenged 40.2% DPPH radicals compared to beta-carotene (31.7%) at a concentration of 0.5 mg ml(-1). The intracellular level of protein oxidation in mutant R1DeltacrtB, which does not contain carotenoid, was 0.0212 mmol mg(-1) protein which is significantly greater than that in the wild type (0.0169 mmol mg(-1) protein) following the treatment with H(2)O(2). The purified major carotenoid product (deinoxanthin) from the wild type showed a greater inhibition of oxidative damage in bovine serum albumin than lycopene or lutein.

CONCLUSIONS

Carotenoids prevent protein oxidation and contribute to the resistance to cell damage in D. radiodurans.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results provide the evidence that carotenoids can protect proteins in D. radiodurans against oxidative stress.

Bone fractures among postmenopausal patients with endocrine-responsive early breast cancer treated with 5 years of letrozole or tamoxifen in the BIG 1-98 trial

BACKGROUND

To compare the incidence and timing of bone fractures in postmenopausal women treated with 5 years of adjuvant tamoxifen or letrozole for endocrine-responsive early breast cancer in the Breast International Group (BIG) 1-98 trial.

METHODS

We evaluated 4895 patients allocated to 5 years of letrozole or tamoxifen in the BIG 1-98 trial who received at least some study medication (median follow-up 60.3 months). Bone fracture information (grade, cause, site) was collected every 6 months during trial treatment.

RESULTS

The incidence of bone fractures was higher among patients treated with letrozole [228 of 2448 women (9.3%)] versus tamoxifen [160 of 2447 women (6.5%)]. The wrist was the most common site of fracture in both treatment groups. Statistically significant risk factors for bone fractures during treatment included age, smoking history, osteoporosis at baseline, previous bone fracture, and previous hormone replacement therapy.

CONCLUSIONS

Consistent with other trials comparing aromatase inhibitors to tamoxifen, letrozole was associated with an increase in bone fractures. Benefits of superior disease control associated with letrozole and lower incidence of fracture with tamoxifen should be considered with the risk profile for individual patients.

The effect of endocrine responsiveness on high-risk breast cancer treated with dose-intensive chemotherapy: results of International Breast Cancer Study Group Trial 15-95 after prolonged follow-up

BACKGROUND

The role of adjuvant dose-intensive chemotherapy and its efficacy according to baseline features has not yet been established.

PATIENTS AND METHODS

Three hundred and forty-four patients were randomized to receive seven courses of standard-dose chemotherapy (SD-CT) or three cycles of dose-intensive epirubicin and cyclophosphamide (epirubicin 200 mg/m(2) plus cyclophosphamide 4 mg/m(2) with filgrastim and progenitor cell support). All patients were assigned tamoxifen at the completion of chemotherapy. The primary end point was disease-free survival (DFS). This paper updates the results and explores patterns of recurrence according to predicting baseline features.

RESULTS

At 8.3-years median follow-up, patients assigned DI-EC had a significantly better DFS compared with those assigned SD-CT [8-year DFS percent 47% and 37%, respectively, hazard ratio (HR) 0.76; 95% confidence interval 0.58-1.00; P = 0.05]. Only patients with estrogen receptor (ER)-positive disease benefited from the DI-EC (HR 0.61; 95% confidence interval 0.39, 0.95; P = 0.03).

CONCLUSIONS

After prolonged follow-up, DI-EC significantly improved DFS, but the effect was observed only in patients with ER-positive disease, leading to the hypothesis that efficacy of DI-EC may relate to its endocrine effects. Further studies designed to confirm the importance of endocrine responsiveness in patients treated with dose-intensive chemotherapy are encouraged.

A randomized trial of anthracycline dose intensification during induction of younger patients with acute myeloid leukemia: Results of Eastern Cooperative Oncology Group study E1900

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Background: In younger adults with newly diagnosed acute myeloid leukemia (AML), anthracycline dose intensification during induction may improve complete remission (CR) rates; however, an improvement in overall survival (OS) in a randomized trial has not been demonstrated. This unresolved issue led the ECOG to compare standard dose (SDD) to high-dose daunorubicin (HDD) in induction. Methods: Adult patients with previously untreated AML were randomized to receive either SDD (45 mg/m2/d) or HDD (90 mg/m2/d) each for 3days combined with standard-dose cytarabine (100 mg/m2/d) for 7 days by continuous intravenous infusion. Those achieving a CR were allocated to allogeneic hematopoietic stem cell transplantation (HSCT) or high-dose cytarabine (with or without a single dose of gemtuzumab ozogamicin) prior to autologous HSCT. Intravenous busulfan and cyclophosphamide was the preparative regimen for both allogeneic and autologous HSCT. The primary end point of this study was OS from the time of induction randomization. Results: 633 patients, age 18 to 60 (median 48) years, were entered in this study. There were no differences in patient demographics or disease characteristics between the two groups at presentation. In an intention-to-treat analysis, HDD resulted in a significantly higher CR rate (63.3% vs. 47.7%, p = 0.0003) than SDD. Induction deaths were similar between the two groups (5.4 vs. 5.0%, p = ns). 334 (52.8%) patients entered the consolidation phase. 57.4% of HDD and 48.1% of the SDD patients, received consolidation therapy on study, and 28.7% and 23.1% proceeded to HSCT respectively. Median OS was superior for the HDD (23.7 months) over the SDD (15.1 months) group (p = 0.005). In subgroup analysis, patients with favorable or intermediate-risk cytogenetics or age <55 years benefited from the HDD. Conclusions: We demonstrate for the first time in a prospective randomized trial that intensifying induction therapy through a higher daily anthracycline dose, in the setting of identical intensive consolidation therapy, results in a higher CR rate as well as prolonged OS. In younger AML patients a higher dose of anthracycline in induction should be considered the new standard of care.

No significant financial relationships to disclose.

Cognitive function in postmenopausal women receiving adjuvant letrozole or tamoxifen in the Breast International Group (BIG) 1–98 trial

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Background: Hormonal therapy for breast cancer (BC) may affect cognition. Methods: Post-menopausal women with hormone receptor positive, early-stage BC were randomized to receive either: A) tamoxifen for 5 years; B) letrozole for 5 years; C) tamoxifen for 2 years followed by letrozole for 3 years; or D) letrozole for 2 years followed by tamoxifen for 3 years, as adjuvant endocrine treatment. During the fifth year of trial treatment, objective cognitive function (speed of psychomotor function, visual attention, working and verbal memory, learning) was evaluated by computerized tests. The difference in the composite score for patients taking letrozole (B+C; N= 65) versus tamoxifen (A+D; N = 55) at the time of testing was the primary comparison. Scores for each domain were standardized according to age-specific norms. Two-way ANOVA controlling for language was used to test the effect of treatment on cognitive function. Self-reported subjective cognitive function, psychological distress, fatigue and quality of life were also assessed. Results: Patient characteristics were balanced between groups. Both groups performed below age norms on most domains. The group taking letrozole had better overall cognitive function than the tamoxifen group (difference in mean composite scores = 0.278, p = 0.038, 95% CI: 0.015–0.540) and outperformed patients on tamoxifen for all domains (n.s.). Comparison of monotherapy arms A versus B supported better cognitive function among letrozole patients. Subjective cognitive function, psychological distress, fatigue, and quality of life did not differ between groups. Conclusions: Although letrozole results in lower circulating estrogen levels than tamoxifen, in this study BC patients taking adjuvant letrozole during the fifth year of treatment had better cognitive functioning than those taking tamoxifen.

[Table: see text]

Advanced Glycation End-products Enhance Calcification in Vascular Smooth Muscle Cells

Advanced glycation end-products (AGEs), senescent macroprotein derivatives formed at an accelerated rate in diabetes, are closely associated with vascular calcification in humans. In this study, the hypothesis that AGEs enhance calcification in cultured vascular smooth muscle cells (VSMCs) was tested. Using real-time polymerase chain reaction (PCR) and specific protein assays, it was demonstrated that rat aortic VSMCs incubated with AGEs exhibited an increased expression of the AGE receptor (RAGE) and typical bone proteins, such as osteopontin and alkaline phosphatase. Incubation with AGEs also enhanced calcium accumulation in VSMCs in time-and dose-dependent manners. These AGEs-mediated changes in VSMCs were partially attenuated by a neutralizing antibody to RAGE. The results suggest that AGEs that accumulate in diabetes could elicit the osteoblastic differentiation of VSMCs, thereby contributing to vascular calcification via the RAGE pathway. Interruption of the AGE-RAGE interaction might be a promising target for therapeutic intervention to prevent diabetic vascular calcification.

Juvenile hormone regulation of male accessory gland activity in the red flour beetle, Tribolium castaneum

Male accessory gland proteins (Acps) act as key modulators of reproductive success in insects by influencing the female reproductive physiology and behavior. We used custom microarrays and identified 112 genes that were highly expressed in male accessory glands (MAG) in the red flour beetle, Tribolium castaneum. Out of these 112 identified genes, 59 of them contained sequences coding for signal peptide and cleavage site and the remaining 53 contained transmembrane domains. The expression of 14 of these genes in the MAG but not in other tissues of male or female was confirmed by quantitative real-time PCR. In virgin males, juvenile hormone (JH) levels increased from second day post adult emergence (PAE), remained high on third day PAE and declined on fourth day PAE. The ecdysteroid titers were high soon after adult emergence but declined to minimal levels from 1 to 5 days PAE. Feeding of juvenile hormone analog, hydroprene, but not the ecdysteroid analog, RH-2485, showed an increase in size of MAGs, as well as an increase in total RNA and protein content of MAG. Hydroprene treatment also increased the expression of Acp genes in the MAG. RNAi-mediated knock-down in the expression of JHAMT gene decreased the size of MAGs and expression of Acps. JH deficiency influenced male reproductive fitness as evidenced by a less vigor in mating behavior, poor sperm transfer, low egg and the progeny production by females mated with the JH deficient males. These data suggest a critical role for JH in the regulation of male reproduction especially through MAG secretions.

Effect of fluoride on the morphology of calcium phosphate crystals grown on acid-etched human enamel

The aim of this study was to examine the effect of fluoride ion concentration on the morphology of calcium phosphate crystals grown on acid-etched enamel as a model for tooth enamel erosion. Samples were immersed in calcification solution for 16 h and changes in crystal morphology were monitored by field emission scanning electron microscopy. Without fluoride, plate-like octacalcium phosphate crystals (20 nm thick, 2-10 microm wide) were formed. With 1-10 mg/l fluoride, arrays of denser needle-like nanocrystals (20-30 nm wide, >500 nm in length) were formed. We conclude that there is a minimal fluoride concentration (1 mg/l) that dramatically affects the morphology of calcium phosphate crystals grown on etched enamel in vitro.

Observation of two-source interference in the photoproduction reaction AuAu --> AuAurho0

In ultraperipheral relativistic heavy-ion collisions, a photon from the electromagnetic field of one nucleus can fluctuate to a quark-antiquark pair and scatter from the other nucleus, emerging as a rho{0}. The rho{0} production occurs in two well-separated (median impact parameters of 20 and 40 F for the cases considered here) nuclei, so the system forms a two-source interferometer. At low transverse momenta, the two amplitudes interfere destructively, suppressing rho{0} production. Since the rho{0} decays before the production amplitudes from the two sources can overlap, the two-pion system can only be described with an entangled nonlocal wave function, and is thus an example of the Einstein-Podolsky-Rosen paradox. We observe this suppression in 200 GeV per nucleon-pair gold-gold collisions. The interference is 87%+/-5%(stat.)+/-8%(syst.) of the expected level. This translates into a limit on decoherence due to wave function collapse or other factors of 23% at the 90% confidence level.

Clinicopathological Variables Associated with Lymph Node Metastasis and Prognostic Factors in pT2 Gastric Cancer

This retrospective study investigated the clinicopathological variables associated with lymph node metastasis and prognosis in 325 patients with pT2 gastric cancer in order to set out a foundation for the surgical management of this condition. Univariate and multivariate analyses identified factors that were predictive of lymph node metastasis. Cox regression analysis evaluated the effect of prognostic factors on survival. Tumour location, maximum tumour diameter, lymphatic invasion and total retrieved lymph nodes (tLN) were revealed as independent factors for lymph node metastasis in pT2a gastric cancer, whereas histological type, lymphatic invasion and tLN were associated with lymph node metastasis in patients with pT2b gastric cancer. Maximum tumour diameter, lymphatic invasion and metastatic lymph node (mLN) ratio, but not tLN, were independent prognostic factors in pT2a cancer. Maximum tumour diameter and mLN ratio, but not tLN, were independent prognostic factors in pT2b cancer. Overall, it is concluded that maximum tumour diameter and mLN ratio are important prognostic factors in pT2 gastric cancer.

Indications of conical emission of charged hadrons at the BNL relativistic heavy ion collider

Three-particle azimuthal correlation measurements with a high transverse momentum trigger particle are reported for pp, d+Au, and Au+Au collisions at sqrt[s_{NN}]=200 GeV by the STAR experiment. Dijet structures are observed in pp, d+Au and peripheral Au+Au collisions. An additional structure is observed in central Au+Au data, signaling conical emission of correlated charged hadrons. The conical emission angle is found to be theta=1.37+/-0.02(stat)-0.07+0.06(syst), independent of p_{ perpendicular}.

The impact of N-ratio in minimizing stage migration phenomenon in gastric cancer patients with insufficient number or level of lymph node retrieved: results from a Chinese mono-institutional study in 2159 patients

BACKGROUND

Previous studies indicate that N-ratio has significant superiority in minimizing 'stage migration' for patients with >15 lymph nodes retrieved. Whether the result is applicable to patients with < or =15 lymph nodes retrieved is still in question.

PATIENTS AND METHODS

Overall survival rates of 2159 gastric cancer patients who underwent radical resection were compared between patients with different number and level of lymph nodes retrieved according to pN [International Union Against Cancer (Union Internationale Contre le Cancer)/AJCC N stage], n (JGCA N stage) and rN (N-ratio) staging system.

RESULTS

Patient number was significantly different between insufficient and sufficient number or level retrieved group in pN and n system, respectively, but not in rN system, while overall survival rates were not significantly different between those groups. The 5-year survival rates of patients with insufficient nodes retrieved were significantly lower than those with sufficient nodes retrieved in pN and n system, but not in rN system. The hazard risk for patients with insufficient nodes retrieved was significantly higher than that for patients with sufficient nodes retrieved in pN and n system, but not in rN system.

CONCLUSION

The rN stage has more potential advantages in minimizing stage migration phenomenon for patients with insufficient number or level of lymph nodes retrieved.

Enamel proteases reduce amelogenin-apatite binding

Organic matrix degradation and crystal maturation are extracellular events that occur simultaneously during enamel biomineralization. We hypothesized that enamel proteases control amelogenin-mineral interaction, which, in turn can affect crystal nucleation, organization, and growth. We used a recombinant amelogenin (rP172), a homolog of its major cleavage product (rP148), and a native amelogenin lacking both N- and C-termini (13k). We compared apatite binding affinity between amelogenins and their digest products during proteolysis. We further compared binding affinity among the 3 amelogenins using a Langmuir model for protein adsorption. Amelogenin-apatite binding affinity was progressively reduced with the proteolysis at the C- and N- termini by recombinant pig MMP-20 (rpMMP20) and recombinant human kallikrein-4 (rhKLK4), respectively. The binding affinity of amelogenin to apatite was found to be in the descending order of rP172, rP148, and 13k. Analysis of our data suggests that, before its complete degradation during enamel maturation, stepwise processing of amelogenin by MMP-20 and then KLK4 reduces amelogenin-apatite interaction.

System-size independence of directed flow measured at the BNL relativistic heavy-ion collider

We measure directed flow (v_{1}) for charged particles in Au+Au and Cu+Cu collisions at sqrt[s_{NN}]=200 and 62.4 GeV, as a function of pseudorapidity (eta), transverse momentum (p_{t}), and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all available model implementations, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to v_{1} in different collision systems, and investigate possible explanations for the observed sign change in v_{1}(p_{t}).

Wideband-tuneable, nanotube mode-locked, fibre laser

Ultrashort-pulse lasers with spectral tuning capability have widespread applications in fields such as spectroscopy, biomedical research and telecommunications. Mode-locked fibre lasers are convenient and powerful sources of ultrashort pulses, and the inclusion of a broadband saturable absorber as a passive optical switch inside the laser cavity may offer tuneability over a range of wavelengths. Semiconductor saturable absorber mirrors are widely used in fibre lasers, but their operating range is typically limited to a few tens of nanometres, and their fabrication can be challenging in the 1.3-1.5 microm wavelength region used for optical communications. Single-walled carbon nanotubes are excellent saturable absorbers because of their subpicosecond recovery time, low saturation intensity, polarization insensitivity, and mechanical and environmental robustness. Here, we engineer a nanotube-polycarbonate film with a wide bandwidth (>300 nm) around 1.55 microm, and then use it to demonstrate a 2.4 ps Er(3+)-doped fibre laser that is tuneable from 1,518 to 1,558 nm. In principle, different diameters and chiralities of nanotubes could be combined to enable compact, mode-locked fibre lasers that are tuneable over a much broader range of wavelengths than other systems.

Forward neutral-pion transverse single-spin asymmetries in p + p collisions at sqrt[s] = 200 GeV

We report precision measurements of the Feynman x (xF) dependence, and first measurements of the transverse momentum (pT) dependence, of transverse single-spin asymmetries for the production of pi0 mesons from polarized proton collisions at sqrt[s] = 200 GeV. The xF dependence of the results is in fair agreement with perturbative QCD model calculations that identify orbital motion of quarks and gluons within the proton as the origin of the spin effects. Results for the pT dependence at fixed xF are not consistent with these same perturbative QCD-based calculations.

CAG repeat lengths > or =335 attenuate the phenotype in the R6/2 Huntington's disease transgenic mouse

With spontaneous elongation of the CAG repeat in the R6/2 transgene to > or =335, resulting in a transgene protein too large for passive entry into nuclei via the nuclear pore, we observed an abrupt increase in lifespan to >20 weeks, compared to the 12 weeks common in R6/2 mice with 150 repeats. In the > or =335 CAG mice, large ubiquitinated aggregates of mutant protein were common in neuronal dendrites and perikaryal cytoplasm, but intranuclear aggregates were small and infrequent. Message and protein for the > or =335 CAG transgene were reduced to one-third that in 150 CAG R6/2 mice. Neurological and neurochemical abnormalities were delayed in onset and less severe than in 150 CAG R6/2 mice. These findings suggest that polyQ length and pathogenicity in Huntington's disease may not be linearly related, and pathogenicity may be less severe with extreme repeats. Both diminished mutant protein and reduced nuclear entry may contribute to phenotype attenuation.