Mutations at the asp locus of Drosophila lead to multiple free centrosomes in syncytial embryos, but restrict centrosome duplication in larval neuroblasts

Mutations at abnormal spindle result in abnormally long and wavy microtubules in the meiotic spindles of males. Some of these spindles have a single pole and take the form of unopposed hemi-spindles. Unfertilised eggs produced by homozygous asp females may have either no nuclei, or a small number of large nuclei, consistent with there also being an effect upon female meiosis. Such eggs also display free centrosomes and independent arrays of microtubules. Embryos that have this phenotype are also present among the progeny of fertilised homozygous asp females, together with embryos that undergo varying degrees of aberrant morphogenesis, developing a variety of abnormal cuticle patterns. This latter category shows asynchronous mitoses prior to cellularisation, and has abnormal arrays of spindle microtubules. Such embryos can develop large areas that are either devoid of or have a reduced number of nuclei, in which there are centrosomes that have dissociated from the mitotic spindles. Neuroblasts in the brains of homozygous asp larvae display a high mitotic index, and have condensed chromosomes aligned as if blocked at metaphase. Immunostaining reveals that many cells contain a single centrosome connected to the metaphase chromosomes by microtubules in a hemi-spindle-like structure

AT1 Receptor Gene Polymorphisms in relation to Postprandial Lipemia

Background. Recent data suggest that the renin-angiotensin system may be involved in triglyceride (TG) metabolism. We explored the effect of the common A1166C and C573T polymorphisms of the angiotensin II type 1 receptor (AT1R) gene on postprandial lipemia. Methods. Eighty-two subjects measured daytime capillary TG, and postprandial lipemia was estimated as incremental area under the TG curve. The C573T and A1166C polymorphisms of the AT1R gene were determined. Results. Postprandial lipemia was significantly higher in homozygous carriers of the 1166-C allele (9.39 ± 8.36 mM*h/L) compared to homozygous carriers of the 1166-A allele (2.02 ± 6.20 mM*h/L) (P < 0.05). Postprandial lipemia was similar for the different C573T polymorphisms. Conclusion. The 1166-C allele of the AT1R gene seems to be associated with increased postprandial lipemia. These data confirm the earlier described relationships between the renin-angiotensin axis and triglyceride metabolism

Transactivation of HER2 by vasoactive intestinal peptide in experimental prostate cancer. Antagonistic action of an analog of growth-hormone-releasing hormone

Receptors for vasoactive intestinal peptide (VIP) and the human epidermal growth factor family of tyrosine kinase receptors (HER) are potent promoters of cell proliferation, survival, migration, adhesion and differentiation in prostate cancer cell lines. In this study, we analyzed the cross-talk between both classes of receptors through the regulation of HER2 transactivation and expression by VIP. Three growth-hormone-releasing hormone analogs endowed with antagonistic activity for VIP receptors (JV-1-51, -52, and -53) abrogated the autocrine/paracrine stimuli of VIP on androgen-independent PC3 cells in the absence or the presence of 10% fetal bovine serum. Semiquantitative and real-time quantitative RT-PCR together with Western blotting showed increased expression levels of both mRNA and proteins for HER2 and HER3 in PC3 and androgen-dependent LNCaP prostate cancer cells as compared to non-neoplastic RWPE-1 cells. VIP (100 nM) stimulated the expression levels of both HER2 and HER3 in PC3 cells in a time-dependent manner. Whereas these effects were relatively slow, VIP rapidly (0.5 min) increased HER2 tyrosine phosphorylation. This pattern of HER transactivation was blocked by H89, a protein kinase A (PKA) inhibitor, as well as by the specific VIP antagonist JV-1-53, indicating the involvement of VIP receptors and PKA activity in phosphorylated HER2 formation. These findings support the merit of further studies on the potential usefulness of VIP receptor antagonists and both HER2 antibodies and tyrosine kinase inhibitors for prostate cancer therapy.Ministerio de Educación y CienciaComunidad de MadridFundación para la Investigación en Urologí

Different Impacts of Cardiovascular Risk Factors on Oxidative Stress

The objective of the study was to evaluate oxidative stress (OS) status in subjects with different cardiovascular risk factors. With this in mind, we have studied three models of high cardiovascular risk: hypertension (HT) with and without metabolic syndrome, familial hypercholesterolemia (FH) and familial combined hyperlipidemia (FCH) with and without insulin resistance. Oxidative stress markers (oxidized/reduced glutathione ratio, 8-oxo-deoxyguanosine and malondialdehide) together with the activity of antioxidant enzyme triad (superoxide dismutase, catalase, glutathione peroxidase) and activation of both pro-oxidant enzyme (NAPDH oxidase components) and AGTR1 genes, as well as antioxidant enzyme genes (CuZn-SOD, CAT, GPX1, GSR, GSS and TXN) were measured in mononuclear cells of controls (n = 20) and patients (n = 90) by assessing mRNA levels. Activity of some of these antioxidant enzymes was also tested. An increase in OS and pro-oxidant gene mRNA values was observed in patients compared to controls. The hypertensive group showed not only the highest OS values, but also the highest pro-oxidant activation compared to those observed in the other groups. In addition, in HT a significantly reduced antioxidant activity and mRNA induction of antioxidant genes were found when compared to controls and the other groups. In FH and FCH, the activation of pro-oxidant enzymes was also higher and antioxidant ones lower than in the control group, although it did not reach the values obtained in hypertensives. The thioredoxin system was more activated in patients as compared to controls, and the highest levels were in hypertensives. The increased oxidative status in the presence of cardiovascular risk factors is a consequence of both the activation of pro-oxidant mechanisms and the reduction of the antioxidant ones. The altered response of the main cytoplasmic antioxidant systems largely contributes to OS despite the apparent attempt of the thioredoxin system to control it

Comparison of Three-phase Active Rectifier Solutions for Avionic Applications: Impact of the Avionic Standard DO-160 F and Failure Modes

In aircraft applications, there has been an increasing trend related with the More Electric Aircraft (MEA), which results in rapid rise in the electrical power demand on-board. One of its goals lies in minimizing weight and volume of the electrical subsystem while maintaining good power quality and efficiency. The main purpose of this paper is to present and analyze an electrical design of a three-phase Boost rectifier, a three-phase Buck rectifier and a three-phase Vienna rectifier for output power level of 10 kW and compare them in terms of weight, volume, efficiency etc. Moreover, the design is obliged to comply with specific sections of DO-160 standard for avionic equipment with 230 VAC, 360-800 Hz grid conditions. Even though all proposed solutions satisfy the standard requirements, it will be shown that the Vienna rectifier has the lowest volume and not considering failure modes, the better solution overall. However, due to increased number of semiconductors and additional circuitry required for soft start-up, the Buck rectifier would prove to be the more robust solution failure-wise

High-throughput identification of genotype-specific cancer vulnerabilities in mixtures of barcoded tumor cell lines.

Hundreds of genetically characterized cell lines are available for the discovery of genotype-specific cancer vulnerabilities. However, screening large numbers of compounds against large numbers of cell lines is currently impractical, and such experiments are often difficult to control. Here we report a method called PRISM that allows pooled screening of mixtures of cancer cell lines by labeling each cell line with 24-nucleotide barcodes. PRISM revealed the expected patterns of cell killing seen in conventional (unpooled) assays. In a screen of 102 cell lines across 8,400 compounds, PRISM led to the identification of BRD-7880 as a potent and highly specific inhibitor of aurora kinases B and C. Cell line pools also efficiently formed tumors as xenografts, and PRISM recapitulated the expected pattern of erlotinib sensitivity in vivo

Parallel Chemical Genetic and Genome-Wide RNAi Screens Identify Cytokinesis Inhibitors and Targets

Cytokinesis involves temporally and spatially coordinated action of the cell cycle and cytoskeletal and membrane systems to achieve separation of daughter cells. To dissect cytokinesis mechanisms it would be useful to have a complete catalog of the proteins involved, and small molecule tools for specifically inhibiting them with tight temporal control. Finding active small molecules by cell-based screening entails the difficult step of identifying their targets. We performed parallel chemical genetic and genome-wide RNA interference screens in Drosophila cells, identifying 50 small molecule inhibitors of cytokinesis and 214 genes important for cytokinesis, including a new protein in the Aurora B pathway (Borr). By comparing small molecule and RNAi phenotypes, we identified a small molecule that inhibits the Aurora B kinase pathway. Our protein list provides a starting point for systematic dissection of cytokinesis, a direction that will be greatly facilitated by also having diverse small molecule inhibitors, which we have identified. Dissection of the Aurora B pathway, where we found a new gene and a specific small molecule inhibitor, should benefit particularly. Our study shows that parallel RNA interference and small molecule screening is a generally useful approach to identifying active small molecules and their target pathways

The PDZ Protein Canoe/AF-6 Links Ras-MAPK, Notch and Wingless/Wnt Signaling Pathways by Directly Interacting with Ras, Notch and Dishevelled

Over the past few years, it has become increasingly apparent that signal transduction pathways are not merely linear cascades; they are organized into complex signaling networks that require high levels of regulation to generate precise and unique cell responses. However, the underlying regulatory mechanisms by which signaling pathways cross-communicate remain poorly understood. Here we show that the Ras-binding protein Canoe (Cno)/AF-6, a PDZ protein normally associated with cellular junctions, is a key modulator of Wingless (Wg)/Wnt, Ras-Mitogen Activated Protein Kinase (MAPK) and Notch (N) signaling pathways cross-communication. Our data show a repressive effect of Cno/AF-6 on these three signaling pathways through physical interactions with Ras, N and the cytoplasmic protein Dishevelled (Dsh), a key Wg effector. We propose a model in which Cno, through those interactions, actively coordinates, at the membrane level, Ras-MAPK, N and Wg signaling pathways during progenitor specification

Fecal carriage of extended-spectrum beta-lactamase-producing Enterobacterales in healthy Spanish schoolchildren

Background: Extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-E) are a serious threat among emerging antibiotic resistant bacteria. Particularly, the number of cases of ESBL-E infections reported in children has been increasing in recent years, and approved antibiotic treatments for this age group are limited. However, information regarding the prevalence of colonization in European children, risk factors associated with colonization, and the characteristics of the colonizing strains is scarce. The aims of this study were to determine the prevalence of ESBL-E colonization in fecal samples of apparently healthy schoolchildren, to identify lifestyle routines associated with colonization, and to characterize clonal relationships and mechanisms of resistance in ESBL-E isolates. Methods: A cohort of 887 healthy children (3-13 years old) from seven primary and secondary schools in the Madrid metropolitan area was recruited between April-June 2018, and sociodemographic information and daily habits were collected. Fecal samples were screened for ESBL-E carriage in selective medium. ESBL-E isolates were further characterized by assessing molecular epidemiology (PFGE and MLST), ESBL gene carriage, and antibiotic resistance profile. This information was analyzed in conjunction with the metadata of the participants in order to identify external factors associated with ESBL-E carriage. Results: Twenty four ESBL-E, all but one Escherichia coli, were detected in 23 children (prevalence: 2.6%; 95% CI: 1.6-3.6%). Of these, seven contained the blaCTX-M-14 allele, five the blaCTX-M-15, five the blaSHV-12, three the blaCTX-M-27, three the blaCTX-M-32, and one the blaCTX-M-9. Significant clonal diversity was observed among the isolates that grouped into 22 distinct clusters (at <85% similarity of PFGE profile). ESBL-producing E. coli isolates belonged to 12 different STs, with ST10 (25%) and ST131 (17%) being the most frequent. Apart from ß-lactams, resistance to trimethoprim/sulfamethoxazole (46%), ciprofloxacin (33%), levofloxacin (33%), tobramycin (21%), and gentamicin (8%) were the most frequently detected. Conclusion: The prevalence of ESBL-E in the studied cohort of children was lower than the average colonization rate previously detected in Europe for both children and adults. E. coli was the main ESBL-producing species detected and CTX-M were the most frequently identified ESBLs. High ST diversity suggests polyclonal dissemination. Compared to other STs, ST131 isolates were associated with resistance to various antimicrobials.ML-S was supported by the Sara Borrell Program of the Instituto de Salud Carlos III (ISCIII) (CD17CIII/00017). ZM was supported by the Río Hortega Program of the ISCIII. AÁ was supported by the Garantía Juvenil Program of the Comunidad Autónoma de Madrid. SS was supported by the Miguel Servet program of ISCIII (CPII18CIII/00005). This study was funded by the ISCIII, Ministry of Economy and Competitiveness (Spain), under projects PI16CIII/00024, PI18CIII/00030, MPY380/18, and MPY516/19.S