Structural optimization and biological evaluation of 2-substituted 5-hydroxyindole-3-carboxylates as potent inhibitors of human 5-lipoxygenase.

Pharmacological suppression of leukotriene biosynthesis by inhibitors of 5-lipoxygenase (5-LO) is a strategy to intervene with inflammatory and allergic disorders. We recently presented 2-amino-5-hydroxy-1H-indoles as efficient 5-LO inhibitors in cell-based and cell-free assays. Structural optimization led to novel benzo[g]indole-3-carboxylates exemplified by ethyl 2-(3-chlorobenzyl)-5- hydroxy-1H-benzo[g]indole-3-carboxylate (compound 11a), which inhibits 5-LO activity in human neutrophils and recombinant human 5-LO with IC50 values of 0.23 and 0.086 μM, respectively. Notably, 11a efficiently blocks 5-LO product formation in human whole blood assays (IC50 = 0.83-1.6 μM) and significantly prevented leukotriene B4 production in pleural exudates of carrageenan-treated rats, associated with reduced severity of pleurisy. Together, on the basis of their high potency against 5-LO and the marked efficacy in biological systems, these novel and straightforward benzo[g]indole-3-carboxylates may have potential as anti-inflammatory therapeutics

Yin Yang 1 is associated with cancer stem cell transcription factors (SOX2, OCT4, BMI1) and clinical implication.

The transcription factor Yin Yang 1 (YY1) is frequently overexpressed in cancerous tissues compared to normal tissues and has regulatory roles in cell proliferation, cell viability, epithelial-mesenchymal transition, metastasis and drug/immune resistance. YY1 shares many properties with cancer stem cells (CSCs) that drive tumorigenesis, metastasis and drug resistance and are regulated by overexpression of certain transcription factors, including SOX2, OCT4 (POU5F1), BMI1 and NANOG. Based on these similarities, it was expected that YY1 expression would be associated with SOX2, OCT4, BMI1, and NANOG's expressions and activities. Data mining from the proteomic tissue-based datasets from the Human Protein Atlas were used for protein expression patterns of YY1 and the four CSC markers in 17 types of cancer, including both solid and hematological malignancies. A close association was revealed between the frequency of expressions of YY1 and SOX2 as well as SOX2 and OCT4 in all cancers analyzed. Two types of dynamics were identified based on the nature of their association, namely, inverse or direct, between YY1 and SOX2. These two dynamics define distinctive patterns of BMI1 and OCT4 expressions. The relationship between YY1 and SOX2 expressions as well as the expressions of BMI1 and OCT4 resulted in the classification of four groups of cancers with distinct molecular signatures: (1) Prostate, lung, cervical, endometrial, ovarian and glioma cancers (YY1(lo)SOX2(hi)BMI1(hi)OCT4(hi)) (2) Skin, testis and breast cancers (YY1(hi)SOX2(lo)BMI1(hi)OCT4(hi)) (3) Liver, stomach, renal, pancreatic and urothelial cancers (YY1(lo)SOX2(lo)BMI1(hi)OCT4(hi)) and (4) Colorectal cancer, lymphoma and melanoma (YY1(hi)SOX2(hi)BMI1(lo)OCT4(hi)). A regulatory loop is proposed consisting of the cross-talk between the NF-kB/PI3K/AKT pathways and the downstream inter-regulation of target gene products YY1, OCT4, SOX2 and BMI1

Systematics of c-axis Phonons in the Thallium and Bismuth Based Cuprate Superconductors

We present grazing incidence reflectivity measurements in the far infrared region at temperatures above and below Tc for a series of thallium (Tl2Ba2CuO6, Tl2Ba2CaCu2O8) and bismuth (Bi2Sr2CuO6, Bi2Sr2CaCu2O8, and Bi(2-x)Pb(x)Sr2CaCu2O8) based cuprate superconductors. From the spectra, which are dominated by the c-axis phonons, longitudinal frequencies (LO) are directly obtained. The reflectivity curves are well fitted by a series of Lorentz oscillators. In this way the transverse (TO) phonon frequencies were accurately determined. On the basis of the comparative study of the Bi and Tl based cuprates with different number of CuO2 layers per unit cell, we suggest modifications of the assignment of the main oxygen modes. We compare the LO frequencies in Bi2Sr2CaCu2O8 and Tl2Ba2Ca2Cu3O10 obtained from intrinsic Josephson junction characteristics with our measurements, and explain the discrepancy in LO frequencies obtained by the two different methods.Comment: 8 pages Revtex, 6 eps figures, 3 tables, to appear in Phys. Rev.

Breaking tolerance in transgenic mice expressing the human TSH receptor A-subunit: thyroiditis, epitope spreading and adjuvant as a 'double edged sword'.

Transgenic mice with the human thyrotropin-receptor (TSHR) A-subunit targeted to the thyroid are tolerant of the transgene. In transgenics that express low A-subunit levels (Lo-expressors), regulatory T cell (Treg) depletion using anti-CD25 before immunization with adenovirus encoding the A-subunit (A-sub-Ad) breaks tolerance, inducing extensive thyroid lymphocytic infiltration, thyroid damage and antibody spreading to other thyroid proteins. In contrast, no thyroiditis develops in Hi-expressor transgenics or wild-type mice. Our present goal was to determine if thyroiditis could be induced in Hi-expressor transgenics using a more potent immunization protocol: Treg depletion, priming with Complete Freund's Adjuvant (CFA) + A-subunit protein and further Treg depletions before two boosts with A-sub-Ad. As controls, anti-CD25 treated Hi- and Lo-expressors and wild-type mice were primed with CFA+ mouse thyroglobulin (Tg) or CFA alone before A-sub-Ad boosting. Thyroiditis developed after CFA+A-subunit protein or Tg and A-sub-Ad boosting in Lo-expressor transgenics but Hi- expressors (and wild-type mice) were resistant to thyroiditis induction. Importantly, in Lo-expressors, thyroiditis was associated with the development of antibodies to the mouse TSHR downstream of the A-subunit. Unexpectedly, we observed that the effect of bacterial products on the immune system is a "double-edged sword". On the one hand, priming with CFA (mycobacteria emulsified in oil) plus A-subunit protein broke tolerance to the A-subunit in Hi-expressor transgenics leading to high TSHR antibody levels. On the other hand, prior treatment with CFA in the absence of A-subunit protein inhibited responses to subsequent immunization with A-sub-Ad. Consequently, adjuvant activity arising in vivo after bacterial infections combined with a protein autoantigen can break self-tolerance but in the absence of the autoantigen, adjuvant activity can inhibit the induction of immunity to autoantigens (like the TSHR) displaying strong self-tolerance

Elucidating mysteries of phase-segregated membranes: Mobile-lipid recruitment facilitates pores' passage to the fluid phase

Phase segregation of multicomponent lipid bilayers leads to, under phase-coexistence conditions, domain formation, featuring delimitation by essentially one-dimensional borders. (Micro-)phase segregation of bilayers is proposed to influence the physiological behaviour of cell membranes and provides the driving force for lipid-raft formation. Experiments show a maximum in the electrical-conductivity of membranes at the phase-transition point, which has been conjectured to arise from border-nucleated transmembrane-conducting defects or pores. However, recent electroporation experiments on phase-segregated bilayers demonstrate electro-pore detection in the liquid disordered phase (Ld), wherein they diffuse over macroscopic periods without absorption into the liquid ordered phase (Lo). Here, we scrutinise transmembrane-pore formation via molecular dynamics simulations on a multicomponent phase-segregated bilayer. We find that pores created in Lo domains always migrate spontaneously to the Ld phase, via 'recruitment' of unsaturated lipids to the pore's rim to transport the pore to the fluid phase under a large stress-field driving force. Once in Ld domains, pores migrate towards their centre, never returning or pinning to Lo. These findings are explained by thermodynamics. By comparing the free-energy cost for creating pores in the bulk of Ld and Lo membranes, and in the phase-segregated system, we show that it is always more energetically tractable to create pores in Ld domains, independent of the pore size.Fil: López Martí, Jesús María. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: English, Niall J.. University College Dublin; IrlandaFil: del Popolo, Mario Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentin

Influence of the Azores high on sea level pressure and wind, and on precipitation, in the Eastern Tropical Pacific Ocean

ENGLISH: Intensification of the Azores high pressure cell in mid-year, with concomitant air flow from the Caribbean into the Pacific, is shown to be responsible for a secondary minimum of precipitation observed along the tropical Pacific coast of the Americas, and to have a measurable effect on wind and precipitation several hundred kilometers offshore. SPANISH: La intensificación de la célula de alta presión de las Azores a mediados del año, y la corriente de aire concomitante que entra al Pacífico procedente del Caribe, se demuestra que es la causante de un mínimo secundario de precipitación observado a lo largo de la costa tropical de las Américas en el Pacífico y que tiene un efecto mensurable sobre el viento y la precipitación varios cientos de kilómetros mar afuera. (PDF contains 23 pages.

In vitro human embryonic stem cell hematopoiesis mimics MYB-independent yolk sac hematopoiesis

Although hematopoietic precursor activity can be generated in vitro from human embryonic stem cells, there is no solid evidence for the appearance of multipotent, self-renewing and transplantable hematopoietic stem cells. This could be due to short half-life of hematopoietic stem cells in culture or, alternatively, human embryonic stem cellinitiated hematopoiesis may be hematopoietic stem cell-independent, similar to yolk sac hematopoiesis, generating multipotent progenitors with limited expansion capacity. Since a MYB was reported to be an excellent marker for hematopoietic stem cell-dependent hematopoiesis, we generated a MYB-eGFP reporter human embryonic stem cell line to study formation of hematopoietic progenitor cells in vitro. We found CD34(+) hemogenic endothelial cells rounding up and developing into CD43(+) hematopoietic cells without expression of MYB-eGFP. MYB-eGFP+ cells appeared relatively late in embryoid body cultures as CD34(+) CD43(+) CD45(-/lo) cells. These MYB-eGFP(+) cells were CD33 positive, proliferated in IL-3 containing media and hematopoietic differentiation was restricted to the granulocytic lineage. In agreement with data obtained on murine Myb(-/-) embryonic stem cells, bright eGFP expression was observed in a subpopulation of cells, during directed myeloid differentiation, which again belonged to the granulocytic lineage. In contrast, CD14(+) macrophage cells were consistently eGFP-and were derived from eGFPprecursors only. In summary, no evidence was obtained for in vitro generation of MYB+ hematopoietic stem cells during embryoid body cultures. The observed MYB expression appeared late in culture and was confined to the granulocytic lineage

Identification of a lineage of multipotent hematopoietic progenitors

All multipotent hematopoietic progenitors in C57BL-Thy-1.1 bone marrow are divided among three subpopulations of Thy-1.1^(lo) Sca-1^+ Lin^(-/lo) c-kit^+ cells: long-term reconstituting Mac-1^-CD4^-c-kit^+ cells and transiently reconstituting Mac-1^(lo)CD4^-or Mac-1^(lo) CD4^(lo) cells. This study shows that the same populations, with similar functional activities, exist in mice whose hematopoietic systems were reconstituted by hematopoietic stem cells after lethal irradiation. We demonstrate that these populations form a lineage of multipotent progenitors from long-term self-renewing stem cells to the most mature multipotent progenitor population. In reconstituted mice, Mac-1- CD4^-c-kit^+ cells gave rise to Mac-1^(lo)CD4^- cells, which gave rise to Mac-1^(lo)CD4^(lo) cells. Mac-1^- CD4^-c-kit^+ cells had long-term self-renewal potential, with each cell being capable of giving rise to more than 10^4 functionally similar Mac-1^-CD4^-c-kit^+ cells. At least half of Mac-1^(lo)CD4^- cells had transient self-renewal potential, detected in the spleen 7 days after reconstitution. Mac-1^(lo)CD4^(lo) cells did not have detectable self-renewal potential. The identification of a lineage of multipotent progenitors provides an important tool for identifying genes that regulate self-renewal and lineage commitment

Circuit-Aware Design of Energy-Efficient Massive MIMO Systems

Densification is a key to greater throughput in cellular networks. The full potential of coordinated multipoint (CoMP) can be realized by massive multiple-input multiple-output (MIMO) systems, where each base station (BS) has very many antennas. However, the improved throughput comes at the price of more infrastructure; hardware cost and circuit power consumption scale linearly/affinely with the number of antennas. In this paper, we show that one can make the circuit power increase with only the square root of the number of antennas by circuit-aware system design. To this end, we derive achievable user rates for a system model with hardware imperfections and show how the level of imperfections can be gradually increased while maintaining high throughput. The connection between this scaling law and the circuit power consumption is established for different circuits at the BS.Comment: Published at International Symposium on Communications, Control, and Signal Processing (ISCCSP 2014), 4 pages, 3 figures. This version corrects an error related to Lemma

Checkpoint-Dependent Regulation of Origin Firing and Replication Fork Movement in Response to DNA Damage in Fission Yeast

To elucidate the checkpoint mechanism responsible for slowing passage through S phase when fission yeast cells are treated with the DNA-damaging agent methyl methanesulfonate (MMS), we carried out two-dimensional gel analyses of replication intermediates in cells synchronized by cdc10 block (in G1) followed by release into synchronous S phase. The results indicated that under these conditions early-firing centromeric origins were partially delayed but late-firing telomeric origins were not delayed. Replication intermediates persisted in MMS-treated cells, suggesting that replication fork movement was inhibited. These effects were dependent on the Cds1 checkpoint kinase and were abolished in cells overexpressing the Cdc25 phosphatase, suggesting a role for the Cdc2 cyclin-dependent kinase. We conclude that both partial inhibition of the firing of a subset of origins and inhibition of replication fork movement contribute to the slowing of S phase in MMS-treated fission yeast cells