Spin-orbit coupled molecular quantum magnetism realized in inorganic solid

Molecular quantum magnetism involving an isolated spin state is of particular interest due to the characteristic quantum phenomena underlying spin qubits or molecular spintronics for quantum information devices, as demonstrated in magnetic metal-organic molecular systems, the so-called molecular magnets. Here we report the molecular quantum magnetism realized in an inorganic solid Ba3Yb2Zn5O11 with spin-orbit coupled pseudospin-1/2 Yb3+ ions. The magnetization represents the magnetic quantum values of an isolated Yb-4 tetrahedron with a total (pseudo) spin 0, 1 and 2. Inelastic neutron scattering results reveal that a large Dzyaloshinsky-Moriya interaction originating from strong spin-orbit coupling of Yb 4f is a key ingredient to explain magnetic excitations of the molecular magnet states. The Dzyaloshinsky-Moriya interaction allows a non-adiabatic quantum transition between avoided crossing energy levels, and also results in unexpected magnetic behaviours in conventional molecular magnets.1141Ysciescopu

Phase II study of weekly paclitaxel and capecitabine in patients with metastatic or recurrent esophageal squamous cell carcinoma

<p>Abstract</p> <p>Background</p> <p>This phase II study assessed the response rate and toxicity profile of weekly paclitaxel and capecitabine in patients with metastatic or recurrent squamous cell carcinoma of the esophagus (SCCE)</p> <p>Methods</p> <p>Patients with histologically confirmed SCCE were treated with paclitaxel 80 mg/m²intravenously on days 1 and 8 plus capecitabine 900 mg/m²orally twice a day on days 1-14. Treatment cycles were repeated every 3 weeks until disease progression or unacceptable toxicity.</p> <p>Results</p> <p>Between 2006 and 2009, 32 patients were enrolled. Twelve patients were chemotherapy-naïve. Twenty patients had received prior chemotherapy including platinum-based regimens. Patients received a median of 5 cycles of treatment (range, 1-12). The response rate was 75% (95%CI; 50.5~99.5%) in the first-line and 45% (95%CI; 26.9~73.1%) in the second-line. With a median follow-up of 20.7 months, median progression-free survival was 5.2 months (95% CI, 4.0 to 6.4) for all patients and median overall survival (OS) was 11.7 months (95% CI, 5.5 to 18.0) for all patients. The median OS was 14.3 months (95% CI, 10.6 to 18.0) for patients receiving therapy as 1^stline and 8.4 months (95% CI, 6.6 to 10.1) for those receiving as 2^nd-line therapy. Grade 3/4 neutropenia was observed in 53.3% of the patients, which was the most common cause of dose reduction. G3 non-hematologic toxicity included stomatitis (9.4%), asthenia (6.3%), and hand-foot skin reaction (3.1%).</p> <p>Conclusions</p> <p>Weekly paclitaxel and capecitabine is a highly active and well-tolerated regimen in patients with metastatic or recurrent SCCE in the first-line as well as second-line setting.</p

Brain structural changes after multi‐strategic metamemory training in older adults with subjective memory complaints: A randomized controlled trial

BACKGROUND: Metamemory is the process of monitoring and controlling one's memory. Improving metamemory may reduce the memory problem in old age. We hypothesized that metamemory training (MMT) would improve cognition in older adults with subjective memory complaints and change the brain region related to metacognition. METHOD: We recruited and randomized older adults to the multi-strategic memory training of 10 weekly 90-min sessions, based on the metamemory concept or usual care. Cognitive tests including the Elderly Verbal Learning Test, Simple Rey Figure Test, Digit Span, Spatial Span, Categorical Fluency, and the Boston Naming Test were done in 201 participants, together with magnetic resonance imaging (MRI) in 49 participants before and after training. RESULTS: A total of 112 in the training group and 89 in the control group participated. The training group had a significant increase in long-term delayed free recall, categorical fluency, and the Boston Naming test. In MRI, the mean diffusivity of the bundles of axon tracts passing from the frontal lobe to the posterior end of the lateral sulcus decreased in the training group. CONCLUSION: These results indicate that the MMT program has a positive impact on enhancing older people' cognitive performance. Improved white matter integrity in the anterior and posterior cerebrum and increased cortical thickness of prefrontal regions, which related to metacognition, possibly suggest that the effects of the MMT would be induced via the enhancement of cognitive control

Chronic allergen challenge induces bronchial mast cell accumulation in BALB/c but not C57BL/6 mice and is independent of IL-9

As genetically engineered mutant mice deficient in single genes are usually generated on a C57BL/6 background, to study mast cell trafficking in mutant mice, we initially investigated whether mast cells accumulated in bronchi in C57BL/6 mice challenged with OVA allergen acutely or chronically for 1 to 3 months. The total number of bronchial mast cells were quantitated using toluidine blue staining in airways of different sizes, i.e. , small (<90 µm), medium (90–155 µm), or large (>150 µm) airways. Non-OVA challenged and acute OVA challenged mice (C57BL/6 and BALB/c) had no detectable bronchial mast cells. Chronic OVA challenge in BALB/c mice for 1 or 3 months induced a significant increase in the number of bronchial mast cells in small-, medium-, and large-sized airways but minimal change in the number of bronchial mast cells in C57BL/6 mice. Both BALB/c and C57BL/6 mice developed significant lung eosinophilia following acute or chronic OVA challenge. Studies of IL-9-deficient mice on a BALB/c background demonstrated a significant increase in the number of bronchial mast cells in IL-9-deficient mice suggesting that IL-9 was not required for the bronchial accumulation of mast cells. Overall, these studies demonstrate that the chronic OVA challenge protocol we have utilized in BALB/c mice provides a model to study the mechanism of bronchial mast cell accumulation and that bronchial mast cell accumulation in chronic OVA challenged mice is independent of IL-9 in this model

Oncoprotein HCCR-1 expression in breast cancer is well correlated with known breast cancer prognostic factors including the HER2 overexpression, p53 mutation, and ER/PR status

<p>Abstract</p> <p>Background</p> <p>Oncoprotein HCCR-1 functions as a negative regulator of the p53 and contributes breast tumorigenesis. The serum HCCR-1 assay is useful in diagnosing breast cancer and mice transgenic for HCCR developed breast cancers. But it is unknown how <it>HCCR-1 </it>contributes to human breast tumorigenesis.</p> <p>Methods</p> <p>Oncogene HCCR-1 expression levels were determined in normal breast tissues, breast cancer tissues and cancer cell lines. We examined whether HCCR-1 protein expression in breast cancer is related to different biological characteristics, including ER, PR, p53 genotype, and HER2 status in 104 primary breast cancer tissues using immunohistochemical analyses.</p> <p>Results</p> <p>HCCR-1 was upregulated in breast cancer cells and tissues compared with normal breast tissues. In this study, overexpression of HCCR-1 was well correlated with known breast cancer prognostic markers including the presence of steroid receptors (ER and PR), p53 mutation and high HER2 overexpression. HCCR-1 was not detected in the ER-negative, PR-negative, p53 negative and low HER2 breast cancer tissues. These data indicate that the level of HCCR-1 in breast cancer tissues is relatively well correlated with known breast cancer factors, including the HER2 overexpression, p53 mutation, and ER/PR status.</p> <p>Conclusion</p> <p>Determination of HCCR-1 levels as options for HER2 testing is promising although it needs further evaluation.</p

Suppression of Lung Tumorigenesis by Leucine Zipper/EF Hand–Containing Transmembrane-1

Leucine zipper/EF hand-containing transmembrane-1 (LETM1) encodes for the human homologue of yeast Mdm38p, which is a mitochondria-shaping protein of unclear function. However, a previous study demonstrated that LETM1 served as an anchor protein for complex formation between mitochondria and ribosome, and regulated mitochondrial biogenesis.Therefore, we examine the possibility that LETM1 may function to regulate mitochondria and lung tumor growth. In this study, we addressed this question by studying in the effect of adenovirus-mediated LETM1 in the lung cancer cell and lung cancer model mice. To investigate the effects of adenovirus-LETM1 in vitro, we infected with adenovirus-LETM1 in A549 cells. Additionally, in vivo effects of LETM1 were evaluated on K-ras(LA1) mice, human non-small cell lung cancer model mice, by delivering the LETM1 via aerosol through nose-only inhalation system. The effects of LETM1 on lung cancer growth and AMPK related signals were evaluated. Adenovirus-mediated overexpression of LETM1 could induce destruction of mitochondria of lung cancer cells through depleting ATP and AMPK activation. Furthermore, adenoviral-LETM1 also altered Akt signaling and inhibited the cell cycle while facilitating apoptosis. Theses results demonstrated that adenovirus-LETM1 suppressed lung cancer cell growth in vitro and in vivo.Adenovirus-mediated LETM1 may provide a useful target for designing lung tumor prevention and treatment

ResBoost: characterizing and predicting catalytic residues in enzymes

Abstract Background Identifying the catalytic residues in enzymes can aid in understanding the molecular basis of an enzyme's function and has significant implications for designing new drugs, identifying genetic disorders, and engineering proteins with novel functions. Since experimentally determining catalytic sites is expensive, better computational methods for identifying catalytic residues are needed. Results We propose ResBoost, a new computational method to learn characteristics of catalytic residues. The method effectively selects and combines rules of thumb into a simple, easily interpretable logical expression that can be used for prediction. We formally define the rules of thumb that are often used to narrow the list of candidate residues, including residue evolutionary conservation, 3D clustering, solvent accessibility, and hydrophilicity. ResBoost builds on two methods from machine learning, the AdaBoost algorithm and Alternating Decision Trees, and provides precise control over the inherent trade-off between sensitivity and specificity. We evaluated ResBoost using cross-validation on a dataset of 100 enzymes from the hand-curated Catalytic Site Atlas (CSA). Conclusion ResBoost achieved 85% sensitivity for a 9.8% false positive rate and 73% sensitivity for a 5.7% false positive rate. ResBoost reduces the number of false positives by up to 56% compared to the use of evolutionary conservation scoring alone. We also illustrate the ability of ResBoost to identify recently validated catalytic residues not listed in the CSA

Pattern recognition receptors as potential therapeutic targets in inflammatory rheumatic disease

The pattern recognition receptors of the innate immune system are part of the first line of defence against pathogens. However, they also have the ability to respond to danger signals that are frequently elevated during tissue damage and at sites of inflammation. Inadvertent activation of pattern recognition receptors has been proposed to contribute to the pathogenesis of many conditions including inflammatory rheumatic diseases. Prolonged inflammation most often results in pain and damage to tissues. In particular, the Toll-like receptors and nucleotide-binding oligomerisation domain-like receptors that form inflammasomes have been postulated as key contributors to the inflammation observed in rheumatoid arthritis, osteoarthritis, gout and systemic lupus erythematosus. As such, there is increasing interest in targeting these receptors for therapeutic treatment in the clinic. Here the role of pattern recognition receptors in the pathogenesis of these diseases is discussed, with an update on the development of interventions to modulate the activity of these potential therapeutic targets

Transgene Silencing and Transgene-Derived siRNA Production in Tobacco Plants Homozygous for an Introduced AtMYB90 Construct

Transgenic tobacco (Nicotiana tabacum) lines were engineered to ectopically over-express AtMYB90 (PAP2), an R2–R3 Myb gene associated with regulation of anthocyanin production in Arabidopsis thaliana. Independently transformed transgenic lines, Myb27 and Myb237, accumulated large quantities of anthocyanin, generating a dark purple phenotype in nearly all tissues. After self-fertilization, some progeny of the Myb27 line displayed an unexpected pigmentation pattern, with most leaves displaying large sectors of dramatically reduced anthocyanin production. The green-sectored 27Hmo plants were all found to be homozygous for the transgene and, despite a doubled transgene dosage, to have reduced levels of AtMYB90 mRNA. The observed reduction in anthocyanin pigmentation and AtMYB90 mRNA was phenotypically identical to the patterns seen in leaves systemically silenced for the AtMYB90 transgene, and was associated with the presence of AtMYB90-derived siRNA homologous to both strands of a portion of the AtMYB90 transcribed region. Activation of transgene silencing in the Myb27 line was triggered when the 35S::AtMYB90 transgene dosage was doubled, in both Myb27 homozygotes, and in plants containing one copy of each of the independently segregating Myb27 and Myb237 transgene loci. Mapping of sequenced siRNA molecules to the Myb27 TDNA (including flanking tobacco sequences) indicated that the 3′ half of the AtMYB90 transcript is the primary target for siRNA associated silencing in both homozygous Myb27 plants and in systemically silenced tissues. The transgene within the Myb27 line was found to consist of a single, fully intact, copy of the AtMYB90 construct. Silencing appears to initiate in response to elevated levels of transgene mRNA (or an aberrant product thereof) present within a subset of leaf cells, followed by spread of the resulting small RNA to adjacent leaf tissues and subsequent amplification of siRNA production