A WC/WO star exploding within an expanding carbon-oxygen-neon nebula.

The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars1 emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars2,3, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion4. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients5-8. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.

Candidate Electromagnetic Counterpart to the Binary Black Hole Merger Gravitational-Wave Event S190521g.

We report the first plausible optical electromagnetic counterpart to a (candidate) binary black hole merger. Detected by the Zwicky Transient Facility, the electromagnetic flare is consistent with expectations for a kicked binary black hole merger in the accretion disk of an active galactic nucleus [B. McKernan, K. E. S. Ford, I. Bartos et al., Astrophys. J. Lett. 884, L50 (2019)AJLEEY2041-821310.3847/2041-8213/ab4886] and is unlikely [

Heparin-binding EGF-like growth factor (HB-EGF) antisense oligonucleotide protected against hyperlipidemia-associated atherosclerosis.

BACKGROUND AND AIMS: Heparin-binding EGF-like growth factor (HB-EGF) is a representative EGF family member that interacts with EGFR under diverse stress environment. Previously, we reported that the HB-EGF-targeting using antisense oligonucleotide (ASO) effectively suppressed an aortic aneurysm in the vessel wall and circulatory lipid levels. In this study, we further examined the effects of the HB-EGF ASO administration on the development of hyperlipidemia-associated atherosclerosis using an atherogenic mouse model. METHODS AND RESULTS: The male and female LDLR deficient mice under Western diet containing 21% fat and 0.2% cholesterol content were cotreated with control and HB-EGF ASOs for 12 weeks. We observed that the HB-EGF ASO administration effectively downregulated circulatory VLDL- and LDL-associated lipid levels in circulation; concordantly, the HB-EGF targeting effectively suppressed the development of atherosclerosis in the aorta. An EGFR blocker BIBX1382 administration suppressed the hepatic TG secretion rate, suggesting a positive role of the HB-EGF signaling for the hepatic VLDL production. We newly observed that there was a significant improvement of the insulin sensitivity by the HB-EGF ASO administration in a mouse model under the Western diet as demonstrated by the improvement of the glucose and insulin tolerances. CONCLUSION: The HB-EGF ASO administration effectively downregulated circulatory lipid levels by suppressing hepatic VLDL production rate, which leads to effective protection against atherosclerosis in the vascular wall.

Adipose differentiation-related protein regulates lipids and insulin in pancreatic islets.

The excess accumulation of lipids in islets is thought to contribute to the development of diabetes in obesity by impairing beta-cell function. However, lipids also serve a nutrient function in islets, and fatty acids acutely increase insulin secretion. A better understanding of lipid metabolism in islets will shed light on complex effects of lipids on beta-cells. Adipose differentiation-related protein (ADFP) is localized on the surface of lipid droplets in a wide range of cells and plays an important role in intracellular lipid metabolism. We found that ADFP was highly expressed in murine beta-cells. Moreover, islet ADFP was increased in mice on a high-fat diet (3.5-fold of control) and after fasting (2.5-fold of control), revealing dynamic changes in ADFP in response to metabolic cues. ADFP expression was also increased by addition of fatty acids in human islets. The downregulation of ADFP in MIN6 cells by antisense oligonucleotide (ASO) suppressed the accumulation of triglycerides upon fatty acid loading (56% of control) along with a reduction in the mRNA levels of lipogenic genes such as diacylglycerol O-acyltransferase-2 and fatty acid synthase. Fatty acid uptake, oxidation, and lipolysis were also reduced by downregulation of ADFP. Moreover, the reduction of ADFP impaired the ability of palmitate to increase insulin secretion. These findings demonstrate that ADFP is important in regulation of lipid metabolism and insulin secretion in beta-cells.

Nuclear hormone receptor-dependent regulation of hepatic transporters and their role in the adaptive response in cholestasis.

1. Hepatobiliary transport systems are essential for the uptake and excretion of a variety of organic anions including bile acids and bilirubin. Perturbation of this vital liver function can result in pathological conditions such as cholestasis, where the formation of bile at the canaliculus is impaired resulting in the intrahepatic accumulation of toxic bile constituents. 2. Members of the nuclear hormone receptor superfamily are important mediators of the adaptive response during cholestasis controlling the expression of transporters and other proteins with the aim to limit tissue damage. Bile acids are the endogenous ligands for these nuclear hormone receptors and therefore directly participate in the control of their own transport and metabolism. 3. Adaptive events include repression of bile acid uptake and de novo bile acid synthesis as well as a concomitant induction of alternative efflux routes and bile acid detoxification. Importantly, the adaptation also extends to other organs such as intestine and kidney to facilitate elimination of bile acids from the body. 4. This review provides an overview of the transcriptional regulation of bile acid transporting proteins and metabolizing enzymes mediated by nuclear hormone receptors. Furthermore, the complex networks between nuclear hormone receptors and regulated genes are illustrated and implications of targeting these receptors for the treatment of cholestasis are discussed.

Checklists for general practitioner diagnosis of depression in adults with intellectual disability.

BACKGROUND: In Australia, diagnosis and management of depression in adults with intellectual disability (ID) often occurs within the primary care setting. Few tools are available to assist general practitioners (GPs) in the diagnostic process. The study aim was to assess properties of carer and GP checklists developed to address this problem. METHOD: Participants were 49 adults with ID and their paid carers (support workers), and GPs for 27 adults. Data from carer and GP checklists were gathered, in addition to carer completed Developmental Behaviour Checklist-Adults (DBC-A). Adults with ID also received a comprehensive psychiatric assessment. RESULTS: Both checklists demonstrated good internal consistency (KRS-20 = 0.90). A factor analysis of the carer checklist indicated a single factor on which three section totals had loadings of greater than 0.722 (depressed mood, loss of interest, and social interaction and communication). This factor was interpreted to be depression. The GP checklist data were insufficient for factor analysis, but section totals were moderately correlated with most corresponding carer checklist section totals. Carer section totals related to depression also correlated highly with the DBC-A Depression sub-scale, demonstrating good concurrent validity. Contrasting results were obtained for the GP checklist. Most (n = 42) of the participants were diagnosed with a psychiatric disorder, precluding the testing of checklist specificity and sensitivity. CONCLUSION: The carer checklist shows promise as a means of gathering information needed by a GP in the diagnosis of depression in adults with ID. Further research into its underlying properties and clinical uses of a combined depression checklist is warranted.

mRNA and protein expression of dog liver cytochromes P450 in relation to the metabolism of human CYP2C substrates.

1. Interpretation of novel drug exposure and toxicology data from the dog is tempered by our limited molecular and functional knowledge of dog cytochromes P450 (CYPs). The aim was to study the mRNA and protein expression of hepatic dog CYPs in relation to the metabolism of substrates of human CYP, particularly those of the CYP2C subfamily. 2. The rate of 7-hydroxylation of S-warfarin (CYP2C9 in humans) by dog liver microsomes (mean +/- SD from 12 (six male and six female) dogs = 10.8 +/- 1.9 fmol mg(-1) protein min(-1)) was 1.5-2 orders of magnitude lower than that in humans. 3. The rate of 4'-hydroxylation of S-mephenytoin, catalysed in humans by CYP2C19, was also low in dog liver (4.6 +/-1.5 pmol mg(-1) protein min(-1)) compared with human liver. In contrast, the rate of 4'-hydroxylation of the R-enantiomer of mephenytoin by dog liver was much higher. The kinetics of this reaction (range of K(m) or K(0.5) 15-22 micro M, V(max) 35-59 pmol mg(-1) protein min(-1), n = 4 livers) were consistent with the involvement of a single enzyme. 4. In contrast to our findings for S-mephenytoin, dog liver microsomes 5'-hydroxylated omeprazole (also catalysed by CYP2C19 in humans) at considerably higher rates (range of K(m) 42-64 micro M, V(max) 22-46 pmol mg(-1) protein min(-1), n = 4 livers). 5. For all the substrates except omeprazole, a sex difference in their metabolism was observed in the dog (dextromethorphan N-demethylation: female range = 0.7-0.9, male = 0.4-0.8 nmol mg(-1) protein min(-1) (p < 0.02); S-warfarin 7-hydroxylation: female = 9-15.5, male = 8-12 fmol mg(-1) protein min(-1) (p < 0.02); R-mephenytoin 4'-hydroxylation: female = 16-35, male = 11.5-19 pmol mg(-1) protein min(-1) (p < 0.01); omeprazole 5'-hydroxylation: female = 15-20, male 13-22 pmol mg(-1) protein min(-1) (p < 0.2)). 6. All dog livers expressed mRNA and CYP3A12, CYP2B11, CYP2C21 proteins, with no sex differences being found. Expression of CYP2C41 mRNA was undetectable in the livers of six of 11 dogs. 7. Correlation analysis suggested that CYP2B11 catalyses the N-demethylation of dextromethorphan (mediated in humans by CYP3A) and the 4'-hydroxylation of mephenytoin (mediated in humans by CYP2C19) in the dog, and that this enzyme and CYP3A12 contribute to S-warfarin 7-hydroxylation (mediated in humans by CYP2C9). 8. In conclusion, we have identified a distinct pattern of hepatic expression of the CYP2C41 gene in the Alderley Park beagle dog. Furthermore, marked differences in the metabolism of human CYP2C substrates were observed in this dog strain compared with humans with respect to rate of reaction, stereoselectivity and CYP enzyme selectivity.

Antisense properties of 2'-O-dimethylaminooxyethyl (2'-O-DMAOE) oligonucleotides.

Antisense oligonucleotides with 2'-O-(2-[N,N-dimethyl)aminooxy]ethyl) or (2'-O-DMAOE) modification were synthesized and evaluated for nuclease resistance and pharmacology both in vitro and in vivo. This modification exhibits very high nuclease resistance and efficacy in various biological (ICAM-1, C-raf and PKC-alpha) targets.

Hepatic distribution of a phosphorothioate oligodeoxynucleotide within rodents following intravenous administration.

The pharmacokinetics of ISIS 1082, a 21-base heterosequence phosphorothioate oligodeoxynucleotide, were characterized within rodent whole liver, and cellular and subcellular compartments. Cross-species comparisons were performed using Sprague-Dawley rat and CD-1 mouse strains. Although whole liver oligonucleotide deposition and the proportion of drug found within parenchymal and nonparenchymal cells were similar between the two rodent species as a function of both time and dose, dramatic differences in subcellular pharmacokinetics were observed. Specifically, within murine hepatocyte nuclei, drug was observed at the 10 mg/kg dose, whereas in the rat nuclear-associated levels required the administration of 25 mg/kg. Under all experimental regimens, murine hepatic nuclear-associated drug concentrations were at least 2-fold higher than those found in rat liver cells. More detailed metabolic analysis was also performed using high performance liquid chromatography/electrospray-mass spectrometry (HPLC/ES-MS) and demonstrated that although the extent of metabolism was similar for rat and mouse, the pattern of n-1 metabolites varied as a function of both species and cell type. While rat and mouse hepatocytes and rat nonparenchymal cellular metabolites were predominantly products of 3'-exonuclease degradation, mouse nonparenchymal cells contained a majority of n-1 metabolites produced by 5'-exonucleolytic activity. Based upon these data, it would appear that subcellular oligonucleotide disposition and metabolism among rodent species are more divergent than whole organ pharmacokinetics might predict.

Comparative radiolabel and ATP analyses of adhesion of Pseudomonas aeruginosa and Staphylococcus epidermidis to hydrogel lenses.

PURPOSE: A comparative assessment of the relative primary adhesion of cells of Pseudomonas aeruginosa, its lux transformant, and of slime and non-slime producing strains of Staphylococcus epidermidis to various hydrogel lenses was conducted. METHODS: Hydrogel lenses were placed in cell suspensions with bacteria with or without a tritiated leucine label. After 2 hours exposure, the lenses were rinsed vigorously and densities of cells on the lenses were determined via scintillation counting or ATP analyses. RESULTS: The radiolabel procedure indicated greater numbers than the ATP analyses of adhered cells per lens per common inoculum of all strains. All strains exhibited greater primary adhesion to the 38% water content contact lens, with the lux transformant of P. aeruginosa showing the greatest degree of adhesion. Primary adhesion by P. aeruginosa was typically at least ten-fold greater per lens than that observed with S. epidermidis. CONCLUSIONS: Both a radiolabel-cell procedure and bioluminescent ATP analyses demonstrated similar patterns of primary adhesion of bacteria to hydrogel lenses. Generally the adhesion increased inversely to the water content of the lenses but the chemical composition of the lenses, particularly surface properties, altered this pattern for lenses of similar water content. The magnitude of primary adhesion varied with the species and strain of bacterium.

Pharmacokinetic and toxicity profile of a phosphorothioate oligonucleotide following inhalation delivery to lung in mice.

Antisense oligonucleotides are currently being investigated for the treatment of a variety of diseases. Antisense drugs are being administered primarily by parenteral injection. To explore more convenient patient delivery methods, we have characterized the tissue kinetics and tolerability of an inhaled aerosol formulation of a phosphorothioate oligonucleotide in mice. Concentrations of oligonucleotide in bronchioalveolar lavage fluid, plasma, and tissue and immunohistochemical localization were used to assess deposition and pharmacokinetic parameters. Significant concentrations of oligonucleotide in lung, as well as systemic tissues, were measured following a pulmonary dose of 12 mg/kg. Doses as low as 1-3 mg/kg also produced significant concentrations of oligonucleotide (>50 microg oligonucleotide per gram of tissue), and these were maintained in the lung with a halflife of 20 hours or greater. Oligonucleotide was localized to bronchiolar epithelium and alveolar epithelium and endothelium. Toxicity was mild at the 12 mg/kg level and minimal to absent at doses of 3 mg/kg or below. Based on a favorable pharmacokinetic profile and a relative lack of toxicity, inhalation delivery appears to be a therapeutic option for antisense oligonucleotides.

Brief report: psychological symptoms in healthy female siblings of adolescents with and without chronic conditions.

OBJECTIVE: To examine the psychological impact of having a sibling with a chronic condition on healthy adolescent females and to explore the potential moderating role of birth order on this relationship. METHOD: We compared selected Brief Symptom Index subscales (anxiety, depression, interpersonal sensitivity, hostility) and global severity scores (GSI) in two groups of healthy, inner-city female adolescents matched for sibling age, gender, birth order, and age spacing: 34 sisters of males and females ages 13-19 years with chronic health conditions (ILLSIBS) and 34 sisters of males and females in the same age range without conditions (WELLSIBS). RESULTS: ILLSIBS generally had more symptoms than WELLSIBS. MANOVA yielded significant three-way interactions of sibling illness status, birth order, and gender for the anxiety, hostility, and GSI. A similar pattern was nonsignificant for the two other subscales. Among younger sisters in general and among older sisters of males only, ILLSIBS had higher scores; however, ILLSIBS who were older sisters of females did not differ significantly in symptom levels from the comparable group of WELLSIBS. CONCLUSIONS: Psychological symptoms in sisters of inner-city, male and female adolescents are related to sibling health status. However, the combination of sibling gender and birth order may modify this relationship and should be considered when evaluating psychological risk or designing interventions.

Phosphorothioate oligodeoxynucleotides distribute similarly in class A scavenger receptor knockout and wild-type mice.

It has been suggested that binding of phosphorothioate oligodeoxynucleotides (P=S ODNs) to macrophage scavenger receptors (SR-AI/II) is the primary mechanism of P=S ODN uptake into cells in vivo. To address the role of scavenger receptors in P=S ODN distribution in vivo, several pharmacokinetic and pharmacological parameters were compared in tissues from scavenger receptor knockout mice (SR-A-/-) and their wild-type counterparts after i.v. administration of 5- and 20-mg/kg doses of P=S ODN. With an antibody that recognizes P=S ODN, no differences in cellular distribution or staining intensity in livers, kidneys, lungs, or spleens taken from SR-A-/- versus wild-type mice could be detected at the histological level. There were no significant differences in P=S ODN concentrations in these organs as measured by capillary gel electrophoresis as well, although the concentration of P=S ODN in isolated Kupffer cells from livers of SR-A-/- mice was 25% lower than that in Kupffer cells from wild-type mice. Furthermore, a P=S ODN targeting murine A-raf reduced A-raf RNA levels to a similar extent in livers from SRA-/- (92.8%) and wild-type (88.3%) mice. Finally, in vitro P=S ODN uptake studies in peritoneal macrophages from SR-A-/- versus wild-type mice indicate that other high- and low-affinity uptake mechanisms predominate. Taken as a whole, our data suggest that, although there may be some contribution to P=S ODN uptake by the SR-AI/II receptor, this mechanism alone cannot account for the bulk of P=S ODN distribution into tissues and cells in vivo, including macrophages.

Metabolism of antisense oligonucleotides in rat liver homogenates.

Phosphorothioate antisense oligodeoxynucleotides are novel therapeutic agents designed to selectively and specifically inhibit production of various disease-related gene products. In vivo pharmacokinetic experiments indicate that these molecules are widely distributed in many species, with the majority of oligomers accumulating within liver and kidney. To better understand the metabolism of these agents, we studied the stability of several phosphorothioate oligodeoxynucleotides, their congeners, and second generation oligomer chemistries in rat liver homogenates. To examine metabolism, background nuclease activity was characterized in whole liver homogenates by using ISIS 1049, a 21-mer phosphodiester oligodeoxynucleotide. Nuclease activity could readily be detected in liver homogenates. Under optimized conditions, the predominant enzymatic activity was 3'-exonucleolytic and could be influenced by pH and ionic conditions. However, in addition to 3' exonucleases, 5' exo- and endonuclease activities were also observed. Our data indicate that metabolism of phosphorothioate oligodeoxynucleotides was more complex than that of phosphodiesters for many reasons, including phosphorothioate oligodeoxynucleotide inhibition of nucleases and the presence of R(p) and S(p) stereoisomers. The rate of phosphorothioate metabolism also appeared to be influenced by sequence, with pyrimidine-rich compounds being metabolized to a greater extent than purine-rich oligomers. Other factors affecting stability included oligomer chemistry and length. Concomitant experiments performed in rats dosed systemically with the same compounds mimic the activities seen in vitro and suggest that this liver homogenate system is a valuable model with which to study the mechanism of metabolism of antisense oligonucleotides.

Variations in mRNA content have no effect on the potency of antisense oligonucleotides.

A fundamental question with regard to antisense pharmacology is the extent to which RNA content or transcription rate or both affect the potency of antisense drugs. We have addressed this by controlling RNA content and transcription rate using either an exogenous gene expressed after transfection or an endogenous gene induced with a cytokine. We have demonstrated that in both A549 and HeLa cells, varying RNA copy numbers from <1 to >100 copies per cell has no effect on the potency of RNase H-active antisense drugs transfected into cells, nor did variation in transcription rate have an effect on potency. We demonstrate that this is because the number of oligonucleotide molecules per cell is vastly in excess of the RNA copy number. These data further suggest that a significant fraction of cell-associated antisense drug molecules may be unavailable to interact with the target RNA, an observation that is not surprising, as phosphorothioate oligonucleotides interact with many cellular proteins. We suggest that these data may extrapolate to in vivo results.

Secular trend in age at menarche in China: a case study of two rural counties in Anhui Province.

There is increasing evidence that age at menarche has decreased in Europe and the United States during the last century and in Japan over the last several decades. Data from a community-based survey conducted in two rural counties of Anhui Province in China indicate a similar, downward secular trend in age at menarche for Chinese women. The present study shows the mean age at menarche decreased by 2.8 years, from 16.5 to 13.7, over an approximate 40-year time interval. This rapid decrease in age at menarche may partly be due to better nutrition and living standards reflected by the improved socioeconomic standards experienced in China over the past few decades. To test this hypothesis, a number of determinants of age at menarche were assessed; year of birth, literacy status, county of residence, amount of physical labour, general health status, pesticide exposure before age at menarche, and drinking water source were all found to be associated with age at menarche.

PIP: This study examined determinants of the mean age at menarche (MAM) in 2 rural counties (Zongyang and Huaining) of Anhui province, China. Data were obtained from a 1993 household community survey among about 12,727 Han women. Years of age were adjusted to account for the Chinese lunar calendar. Analysis pertains to 5-year birth cohorts during 1949-78 compared to all cohorts born before 1949. MAM declined from 16.5 years to 13.7 years over a 40-year period. The trend was linear. Year of birth and level of education were strongly related to a decrease in MAM. MAM was also significantly associated with county, physical labor, general health status, exposure to pesticides before age at menarche, and water source. Year of birth explained most of the difference in MAM. There were no significant interactions between birth year and literacy, water source, or pesticide exposure, or between county and amount of physical labor. Women from Zongyang county had a later MAM than women from Huaining. Illiterate women had a higher MAM than literate women. The decline in MAM is attributed to improved nutritional status and living standards since World War II. 788 women reported a MAM that was older than 19 years. Subtracting these women only resulted in a decrease in MAM to 15.9 years for the pre-1949 cohort. Findings suggest a similar MAM for Anhui province as for China as a whole.

Oligonucleotide Therapeutics--IBC Sixth International Conference. 3-5 May 1999, La Jolla, CA, USA.

A wide array of strategies was presented for exploiting antisense oligonucleotides (AS ONs). Vitravene (ISIS Pharmaceuticals Inc), a first-generation phosphorothioate (PS) oligodeoxynucelotide (ODN) has been approved for use in the US and European markets for the treatment of CMV retinitis. A number of pharmaceutical companies introduced numerous compounds in both phase I and pivotal phase II clinical trials, for treatment of a wide range of diseases, including cancer, inflammation and viral agents. Advances in AS ON delivery were also described, including topical and oral routes of administration. New chemical modifications incorporated into second-generation oligonucleotides demonstrated superior potency and duration of action in a number of preclinical models. Finally, in response to the explosion in new genomic sequence information generated by the Human Genome Project, a number of companies are combining bioinformatics with high-throughput screening (HTS) to rapidly discover new drug targets. As a result, there was much excitement exhibited by researchers attending this meeting and a strong feeling that this new drug paradigm is delivering on its initial promise.

In vivo distribution and metabolism of a phosphorothioate oligonucleotide within rat liver after intravenous administration.

In the rat, the liver represents a major site of phosphorothioate oligodeoxynucleotide deposition after i.v. administration. For this reason, we examined the intracellular fate of ISIS 1082, a 21-base heterosequence phosphorothioate oligodeoxynucleotide, isolated from parenchymal and nonparenchymal cell types after systemic dosing using established perfusion and separation techniques followed by CGE. Isolated cells were further fractionated into nuclear, cytosolic and membrane constituents to assess the intracellular localization, distribution and metabolic profiles as a function of time and dose. After a 10-mg/kg i.v. bolus, intracellular drug levels where maximal after 8 hr and diminished significantly thereafter, suggesting an active efflux mechanism or metabolism. Nonparenchymal (i.e., Kupffer and endothelial) cells contained approximately 80% of the total organ cellular dose, and this was equivalently distributed between the two cell types, while the remaining 20% was associated with hepatocytes. Nonparenchymal cells contained abundant nuclear, cytosolic and membrane drug levels over a wide dose range. In contrast, at doses of less than 25 mg/kg, hepatocytes contained significantly less drug with no detectable nuclear-association. Doses at or above 25 mg/kg appeared to saturate nonparenchymal cell types, whereas hepatocytes continued to accumulate drug in all cellular compartments, including the nucleus. Our results suggest that although pharmacokinetic parameters vary as a function of hepatic cell type, significant intracellular delivery can be readily achieved in the liver after systemic administration.