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 stars^2,3, 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 transients^5-8. 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 [<O(0.01%))] due to intrinsic variability of this source. The lack of color evolution implies that it is not a supernova and instead is strongly suggestive of a constant temperature shock. Other false-positive events, such as microlensing or a tidal disruption event, are ruled out or constrained to be <O(0.1%). If the flare is associated with S190521g, we find plausible values of total mass M_{BBH}∼100  M_{⊙}, kick velocity v_{k}∼200  km s^{-1} at θ∼60° in a disk with aspect ratio H/a∼0.01 (i.e., disk height H at radius a) and gas density ρ∼10^{-10}  g cm^{-3}. The merger could have occurred at a disk migration trap (a∼700r_{g}; r_{g}≡GM_{SMBH}/c^{2}, where M_{SMBH} is the mass of the active galactic nucleus supermassive black hole). The combination of parameters implies a significant spin for at least one of the black holes in S190521g. The timing of our spectroscopy prevents useful constraints on broad-line asymmetry due to an off-center flare. We predict a repeat flare in this source due to a reencountering with the disk in ∼1.6  yr(M_{SMBH}/10^{8}  M_{⊙})(a/10^{3}r_{g})^{3/2}.

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.

The Effect of Y and Zr on the Oxidation of NiA1

The effect of Y and Zr on the oxidation behaviour of NiAl has been investigated using high resolution SIMS and analytical TEM. 18O tracer experiments in conjunction with SIMS showed that Y and Zr reduce the outward transport of cations during the growth of the AI2O3 scale. Complementary STEM-EDS measurements revealed segregation of Y and Zr at the metal/oxide interface as well as the grain boundaries in the AI2O3 scale. The amounts of segregation at both the interface and grain boundary were calculated to be less than one monolayer.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Comparison of methods for the reduction of acute pain produced by rubber ring castration or tail docking of week-old lambs

Behavioural and plasma cortisol changes were recorded for groups of eight Suffolk x Greyface lambs subjected to castration or tail docking using rubber rings with and without local anaesthetic treatment. Immediately after application of the rubber ring, local anaesthetic (2 x 0.2 ml 2% lignocaine) was administered either by needle and syringe or by high-pressure needleless injection into each side of the neck of the scrotum or tail at the site of the ring, or by high pressure needleless injection into the testes before ring application. In other groups, the innervation to the scrotum or tail was disabled by crushing with a powered bloodless castrator just proximal to the ring. Measurements were recorded in groups of control (handled) lambs, with and without local anaesthetic treatment. Application of local anaesthetic by high pressure needleless injection had little effect on either plasma cortisol values or behaviour of control lambs. For castration, application of the bloodless castrator and/or local anaesthetic at the ring site reduced the peak plasma cortisol concentration by 50% (P < or = 0.01), the incidence of active behavioural responses by 80 and 64% (P < or = 0.01) respectively, and the time spent in abnormal postures by 68 and 59% (P < or = 0.01) respectively. Both methods were effective in reducing pain for tail docking [active behavioural responses reduced by more than 80% (P < or = 0.01) and abnormal postures by 56% (P < or = 0.01)], although local anaesthetic was more effective, reducing the peak cortisol by 60% (P < or = 0.01) [crushing by 44% (P > 0.05)]. Injection of local anaesthetic into the testes was less effective than injection into the neck of the scrotum at the site of the ring [reduction in abnormal lying postures (P < or = 0.05), 45 vs 71%, respectively]. The rapid action, effectiveness, and ease of application of these experimental methods may provide the basis for commercially viable methods for reducing the acute pain produced by rubber ring castration and tail docking of lambs.

Reduction in pain suffered by lambs at castration

The acute pain produced by bloodless castrators was studied by comparing the behavioural and plasma cortisol changes in groups (n=8) of 3-week-old Dorset cross lambs after castration with a 22 cm (9") Burdizzo, a new power assisted castrator and by a combined method using a Burdizzo and elastrator ring. The time spent in abnormal postures (52-58 min) and the peak cortisol response (110-120 mmol l(-1)) were similar for the three methods, although the powered castrator produced a more sustained response. The Burdizzo method halved the incidence of active behaviours compared with the powered castrator and combined methods (16 versus 30, 32 counts). Intratesticular local anaesthetic administered 2 min before the Burdizzo castrator and combined method, or intramuscular injection of the non-steroidal anti-inflammatory drug diclofenac, 20 min before the application of a Burdizzo, significantly reduced the peak plasma cortisol response to 80 nmol l(-1). Diclofenac also significantly reduced the time spent trembling or in abnormal postures.

Effects of four analgesic treatments on the behavioural and cortisol responses of 3-week-old lambs to tail docking

The behavioural and cortisol responses of groups of seven or eight lambs were used to determine which of three methods of tail docking (rubber ring, Burdizzo and rubber ring combined, or heated docking iron) produced the least signs of pain in the first 3 h after use and which of four analgesic treatments (1.0 ml bupivacaine subcutaneously, 0.5 ml bupivacaine epidurally, a topical cold analgesic spray or diclofenac 1.5 mg kg-1) was most effective in reducing these signs. Amputation with a heated docking iron produced levels of behaviour and cortisol responses which did not differ markedly from those of handled controls. The rubber ring method produced the greatest increase in all parameters (total active behaviour 110 +/- 91 counts; 51 +/- 23 min spent in abnormal postures; peak cortisol 93 +/- 51 nmol l-1). Subcutaneous bupivacaine, administered immediately prior to application of the ring, appeared to be the analgesic treatment most effective at reducing these responses (23 +/- 15 counts; 24 +/- 22 min.; 44 +/- 20 nmol l-1).

Effect of antisense oligonucleotides on cytokine release from human keratinocytes in an in vitro model of skin

ISIS 1082, a phosphorothioate oligonucleotide 21 nucleotides in length targeted to the translation initiation codon of herpes simplex virus (HSV) type 1 and 2 virion capsid protein, has been shown to inhibit HSV-1 replication in vitro. The effects of ISIS 1082, its phosphodiester congener, ISIS 1049, and analogs consisting of 2' methoxy and 2' propoxy phosphodiesters and phosphorothioates on IL-1 alpha release and viability were evaluated in a three-dimensional in vitro skin model consisting of neonatal keratinocytes and fibroblasts. This in vitro system displays many of the functional and metabolic properties of a differentiated epidermis and can be induced to specifically release IL-1 alpha in response to a mixture of lipopolysaccharide and phorbol myristate acetate. Incubation of the skin model with 250 to 1000 microM concentrations of ISIS 1082 and its 2' methoxy and propoxy phosphorothioate analogs resulted in a concentration-dependent increase of cytokine release with minimal effects on cellular viability, as measured by the Neutral Red assay. This response was confirmed in primary keratinocytes, which were also shown to secrete IL-1 alpha into media supernatants after incubation with phosphorothioate oligomers. These data suggest that the IL-1 alpha released from keratinocytes in response to ISIS 1082 may contribute to the inflammatory and immune cell response seen in vivo.

Comparative hypolipidaemic and peroxisomal effects of ciprofibrate, clofibric acid, and their respective difluorocyclopropyl and 4-fluoro-substituted analogues in rat

1. We investigated the biological activity of the difluoro analogue (WIN 36117) of ciprofibrate, a potent peroxisome proliferator, and re-examined the relative activity of clofibric acid and its 4-fluoro analogue (fluorofibric acid) in the rat. 2. Twenty-four hours after a single dose, ciprofibrate and WIN 36117 produced dosage-related reductions in plasma cholesterol (16-42 and 9-34% respectively) and triglycerides (14-32 and 9-22% respectively). However, a single dose of clofibric acid or fluorofibric acid produced hypocholesterolaemia only (32-58 and 9-29% reductions respectively). 3. After treatment for 7 days reductions in cholesterol were similar at all dosages of ciprofibrate (45% reduction, mean across groups) whereas the effects of WIN 36117, clofibric acid and fluorofibric acid were still dosage related (reductions of 21-44, 37-43 and 2-28% respectively). Hypotriglyceridaemia was produced by all compounds (ciprofibrate 36-50%, WIN 36117 14-36%, clofibric acid 18-48%, fluorofibric acid 6-28%). 4. After treatment for 14 days all compounds produced dosage-related decreases in plasma fibrinogen (ciprofibrate 18-33%, WIN 36117 7-11%, clofibric acid 13-26%, fluorofibric acid 7-15%). 5. Peroxisomal beta-oxidation activity was increased by WIN 36117 (4.8-fold) and fluorofibric acid (4.2-fold) although these increases were less than those produced by ciprofibrate (13.6-fold) and clofibric acid (7.0-fold). WIN 36117 and fluorofibric acid also produced smaller increases in peroxisome numbers, liver weight, and carnitine acetyl transferase activity and smaller decreases in glutathione S-transferase and glutathione peroxidase activities. 6. Maximal increases in peroxisomal beta-oxidation activity produced in cultured rat hepatocytes by WIN 36117 and fluorofibric acid were 58 and 72% of those produced by ciprofibrate and clofibric acid respectively. 7. These results indicate the difluoro and 4-fluoro analogues of ciprofibrate and clofibric acid are hypolipidaemic agents and peroxisome proliferators but with reduced potencies relative to the parent molecules.

Pharmacokinetic properties of several novel oligonucleotide analogs in mice

Biophysical and pharmacokinetic properties of five analogs of ISIS 3082, a 20-mer phosphorothioate oligodeoxynucleotide that inhibits the expression of mouse intercellular adhesion molecule 1, were evaluated. Compared to the parent compound, ISIS 3082, the 2'-propoxy modified phosphodiester, ISIS 9044 and the 2'-propoxy phosphorothioate, ISIS 9045, had greater affinity for complementary RNA and were more lipophilic. A chimeric oligonucleotide comprised of 2'-propoxy diester wings and a phosphorothioate deoxy center (ISIS 9046) had equal affinity. It was also more lipophilic than ISIS 3082, but less so than the other 2'-propoxy modified analogs. The two analogs with 5'-lipophilic conjugates, ISIS 9047 (5'-octadecylamine) and ISIS 8005 (5'-(2'-O-hexylamino-carbonyl-oxycholesterol) were more lipophilic than ISIS 3082 (3- and 7-fold, respectively) but had similar affinity for complementary RNA. Binding of ISIS 3082 to bovine serum albumin was salt-dependent and, at physiological concentration (320 mOsmol), the dissociation constant (Kd) was 140 microM. Similarly, the 2'-propoxy phosphodiester, ISIS 9044, displayed salt-dependent bovine serum albumin binding, but not binding was measurable at physiological salt conditions. In contrast, the more lipophilic phosphorothioate analogs displayed much higher affinity to bovine serum albumin at 320 mOsmol than ISIS 3082. After bolus injection to mice, the initial volumes of distribution of the more lipophilic phosphorothioate analogs, ISIS 9045, ISIS 9047 and ISIS 8005, were less and the initial clearance from plasma was slower than ISIS 3082. The pharmacokinetics of the other analogs was similar to ISIS 3082. Distribution of ISIS 3082 into peripheral tissues was similar to that reported for other phosphorothioates with liver and kidney accumulating the highest fraction of the dose. The only modification to markedly influence distribution was the very lipophilic cholesterol conjugate (ISIS 8005), which increased substantially the fraction of the dose accumulated by the liver. Little intact drug was found in urine or feces for any analog, and the patterns of metabolites suggested that for all analogs the principal metabolic pathway was due to 3'-exonuclease activity. The metabolism of ISIS 3082 was similar to that reported for other phosphorothioates. After 2 hr, most of the radioactivity in plasma represented metabolites but, in tissues, intact ISIS 3082 was present for much longer periods of time and metabolites accumulated more slowly. The 24-hr exposure to ISIS 3082 of liver and kidney was 20.7 and 67.9 microM/hr, respectively. The rates of metabolism in plasma, liver and kidney of the two 5'-conjugates, ISIS 9047 and ISIS 8005, were similar to ISIS 3082, as was the pattern of metabolism. The rate of metabolism of ISIS 9044 (2'-propoxy phosphodiester oligonucleotide) was much more rapid in liver and plasma, but surprisingly much slower in the kidney. ISIS 9045 (full 2-propoxy phosphorothioate) was much more stable than ISIS in all tissues, the enhanced stability of ISIS 9045 resulted in increased exposure of liver and kidney to the drug, whereas the exposure of the liver to the two more lipophilic analogs, ISIS 9047 and ISIS 8005, was greater because a higher fraction of the dose was distributed to the liver. The exposure of the kidney to ISIS 9044 was also greater than that to ISIS 3082 due to the surprising stability of the drug in the kidney.

Quantitation of phosphorothioate oligonucleotides in human plasma

Methods are presented for the extraction of phosphorothioate oligonucleotides from human plasma to permit quantitation by capillary gel electrophoresis. Extraction of the phosphorothioate oligonucleotides from plasma was accomplished using two solid-phase extraction columns, a strong anion-exchange column to remove plasma proteins and lipids, followed by a reverse-phase column to remove salts. A second desalting step, achieved by dialysis utilizing a membrane with a molecular weight cutoff of 2500 Da floating on distilled water, was required to remove residual ionic material from the extracted sample. This method should be generally applicable to the analysis and quantitation of phosphorothioate oligonucleotides.

Enhanced activity of an antisense oligonucleotide targeting murine protein kinase C-alpha by the incorporation of 2'-O-propyl modifications

We have previously described the characterization of a 20mer phosphorothioate oligodeoxynucleotide (ISIS 4189) which inhibits murine protein kinase C-alpha (PKC-alpha) gene expression, both in vitro and in vivo. In an effort to increase the antisense activity of this oligonucleotide, 2'-O-propyl modifications have been incorporated into the 5'- and 3'-ends of the oligonucleotide, with the eight central bases left as phosphorothioate oligodeoxynucleotides. Hybridization analysis demonstrated that these modifications increased affinity by approximately 8 and 6 degrees C per oligonucleotide for the phosphodiester (ISIS 7815) and phosphorothioate (ISIS 7817) respectively when hybridized to an RNA complement. In addition, 2'-O-propyl incorporation greatly enhanced the nuclease resistance of the oligonucleotides to snake venom phosphodiesterase or intracellular nucleases in vivo. The increase in affinity and nuclease stability of ISIS 7817 resulted in a 5-fold increase in the ability of the oligonucleotide to inhibit PKC-alpha gene expression in murine C127 cells, as compared with the parent phosphorothioate oligodeoxynucleotide. Thus an RNase H-dependent phosphorothioate oligodeoxynucleotide can be modified as a 2'-O-propyl 'chimeric' oligonucleotide to provide a significant increase in antisense activity in cell culture.

In vitro pharmacokinetics of phosphorothioate antisense oligonucleotides

ISIS 2105 (Afovirsen), a 20-mer phosphorothioate oligonucleotide that inhibits the production of a gene product essential to the growth of human papillomavirus, is in phase II clinical trials for the treatment of genital warts induced by human papillomavirus-6 and human papillomavirus-11. The uptake, subcellular distribution and metabolism of ISIS 2105 and three other similar length phosphorothioates have been studied in a variety of cell lines. Our experiments indicated that ISIS 2105 and other phosphorothioates are internalized and distributed in a time-, temperature-, concentration-, sequence- and cell line-dependent manner. Cell association was also influenced by the tissue culture medium. Several different analytical techniques revealed that phosphorothioates were more rapidly degraded in vitro than previously reported. These data suggest that phosphorothioate oligonucleotide uptake and stability observed in tissue culture can vary as a function of cellular assay conditions and analytical methods used. Comparison of these results with those obtained in vivo suggests that the pharmacokinetic behavior of this class of compounds cannot necessarily be predicted from in vitro studies.

The relative hypolipidaemic activity and hepatic effects of ciprofibrate enantiomers in the rat

The aim of this study was to establish whether the individual enantiomers of racemic ciprofibrate, a potent hypolipidaemic agent and peroxisome proliferator, differ significantly in either pharmacological potency or toxic potential. After a single oral dose to male Fischer F344 rats at dosages below 10 mg/kg, S(-) ciprofibrate produced slightly, but statistically significantly, greater reductions in plasma concentrations of cholesterol than R(+) ciprofibrate. Similarly, at low concentrations in F344 rat hepatocyte cultures, S(-) ciprofibrate produced slightly, but statistically significantly, greater inductions of peroxisomal beta-oxidation activity than R(+) ciprofibrate. However, after seven daily doses, the differences in pharmacological effects of the two enantiomers were no longer apparent. Furthermore, in contrast to its effects in vitro, R(+) ciprofibrate produced slightly, but statistically significantly, greater inductions of peroxisomal beta-oxidation activity in vivo than S(-) ciprofibrate. These observations may be possibly explained on the basis that following multiple dosing, plasma concentrations of R(+) ciprofibrate 24 hr post-dose were greater than those of its optical antipode. Thus the slightly greater potency of the S(-) enantiomer after a single dose may have been overcome by the greater plasma concentrations of the less potent enantiomer. Both enantiomers produced similar reductions in plasma concentrations of thyroxine. The data indicate that at low dosages S(-) ciprofibrate is a slightly more potent hypolipidaemic agent after a single dose in rats and a slightly more potent peroxisome proliferator at low concentrations in vitro. However, following multiple dosing, both enantiomers produced changes in plasma concentrations of lipids, hepatic enzyme activities and plasma concentrations of thyroxine which were of comparable magnitude to those produced by the racemate. Since these early changes have been linked mechanistically to the chronic toxicity of the racemate in the rat, it could be predicted that the individual enantiomers of ciprofibrate under conditions employed in chronic safety studies, would produce the same spectrum of rodent toxicity as the racemate.

Relationship between genome size and maturity group in soybean

Previous studies have reported a correlation between genome size and relative maturity among plant species. The objective of this study was to determine whether such a relationship exists in soybean. Twenty cultivars, representing maturity groups ranging from 000 to IX, were analyzed using flow cytometric procedures. A 15% difference in genome size was observed ranging from 'BSR 201' at 2.88 pg to 'Maple Presto' at 2.51 pg. A highly significant correlation (r = 0.55) was observed between maturity and the genome size of the 20 cultivars.

Lack of peroxisome proliferation in marmoset liver following treatment with ciprofibrate for 3 years

The effect of treatment of marmosets with ciprofibrate for 3 years on activities of hepatic enzymes, hepatic histomorphology, and ultrastructure were investigated. Male and female marmosets were dosed with ciprofibrate (2, 10, and 20 mg/kg) by oral gavage once daily for 3 years. No effect on liver weight (adjusted for body weight) or liver morphology was observed. The activities of catalase, glutathione peroxidase, alpha-glycerophosphate dehydrogenase, benzphetamine N-demethylase, and ethoxyresorufin O-deethylase were unaffected by treatment with ciprofibrate. Activity of glutathione transferase was increased in the low dosage group but unaffected in the mid and high dosage groups. Modest increases in activities of peroxisomal beta-oxidation (2.5-fold, maximal), carnitine acetyl transferase (1.7-fold, maximal), and carnitine palmitoyl transferase (2-fold, maximal) were observed. Cytochemical staining and quantitative image analysis failed to indicate any effect on peroxisomal number, size, or volume density. Similarly, there was no increase in lipofuscin deposition. This study provides data on the effects of a potent peroxisome proliferator on primate liver following a dosing period much greater than that used in previously published studies and is further evidence that the marmoset is relatively insensitive to the well-documented effects that ciprofibrate and other peroxisome proliferators have on rat liver.

Tritium labeling of antisense oligonucleotides by exchange with tritiated water

We describe a simple, efficient, procedure for labeling oligonucleotides to high specific activity (< 1 x 10(8) cpm/mumol) by hydrogen exchange with tritiated water at the C8 positions of purines in the presence of beta-mercaptoethanol, an effective radical scavenger. Approximately 90% of the starting material is recovered as intact, labeled oligonucleotide. The radiolabeled compounds are stable in biological systems; greater than 90% of the specific activity is retained after 72 hr incubation at 37 degrees C in serum-containing media. Data obtained from in vitro cellular uptake experiments using oligonucleotides labeled by this method are similar to those obtained using 35S or 14C-labeled compounds. Because this protocol is solely dependent upon the existence of purine residues, it should be useful for radiolabeling modified as well as unmodified phosphodiester oligonucleotides.

Protein kinase C beta expression in melanoma cells and melanocytes: differential expression correlates with biological responses to 12-O-tetradecanoylphorbol 13-acetate

Normal human melanocytes require 12-O-tetradecanoylphorbol 13-acetate (TPA) for prolonged growth in vitro. In contrast, the growth of human malignant melanoma cells is often inhibited by TPA. In this study, we have confirmed and extended these observations. Since protein kinase C (PKC) is an important mediator of the effects of TPA, we have investigated the nature of this differential growth response by examining PKC expression and activity in primary cultures of human neonatal melanocytes and metastatic melanoma cell strains. PKC, when measured by immunoreactivity or a functional assay, was found to be more abundant in melanoma cells than in melanocytes. When specific isotypes were examined by Northern analysis, PKC-alpha and -epsilon were expressed in both melanocytes and melanoma. PKC-beta was expressed in melanocytes, but was undetectable by Northern analysis in 10 out of 11 melanoma cell strains. Southern analysis revealed that no gross deletions or rearrangements of the PKC-beta gene had occurred. These data suggest that down-regulation of the PKC-beta gene occurs frequently during the process of transformation of melanocytes. Furthermore, differential expression of PKC isotypes may explain the different effects of TPA on melanocyte and melanoma cell growth.

Comparison of calmodulin gene expression in human neonatal melanocytes and metastatic melanoma cell lines

The qualitative and quantitative expression of three calmodulin genes (CAM I, CAM II and CAM III) was characterized in human neonatal melanocytes and metastatic melanoma cell lines in the absence and presence of serum, other growth modulators, and/or 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Results indicated that the qualitative expression in melanocytes was the same as that of melanomas, that is, CAM I gene expressed two transcripts, 4.4 kb and 2.1 kb, whereas CAM II and CAM III expressed one transcript each, 1.95 kb and 2.37 kb, respectively. Differential quantitative expression was seen particularly with CAM I. The average levels of both CAM I transcripts in melanomas were less than one-half those of melanocytes. Serum and other growth modulators (including Ca++, isobutyl methyl xanthine, bovine pituitary extract, and insulin) enhanced CAM I and CAM II gene expression in melanocytes; in contrast, the net effect of serum in melanomas was to decrease expression of CAM I and CAM III. This effect was most prominent in melanoma C81-46C. TPA markedly inhibited expression of all three CaM genes in melanocytes; however, in melanomas the net effect of TPA was to increase their expression. CAM I in melanoma C81-46C was the most sensitive to TPA stimulation.

Differences in basic fibroblast growth factor RNA and protein levels in human primary melanocytes and metastatic melanoma cells

Cultivation of human melanocytes requires several growth factors for cell proliferation. For example, basic fibroblast growth factor (bFGF) is an essential growth agent for melanocyte proliferation in vitro and has been proposed to be an autocrine growth factor in human melanoma cells. Studies using either anti-bFGF antibodies or antisense oligonucleotides partially inhibited the proliferation of human melanoma cells. However, one group was unable to detect bFGF RNA transcripts in human melanoma cells using a human complementary DNA probe. These contradictory results prompted us to investigate the bFGF gene expression in human primary melanocytes and metastatic melanoma cells using Southern, Northern, and Western blot analyses. No gross rearrangements in the bFGF gene were detected in the genomic DNA. Although high levels of bFGF RNA transcripts were detected in melanocytes, no bFGF protein was detected using Western blot analysis. In contrast, melanoma cells expressed much lower levels of bFGF RNA transcripts, and cells from three of four cell strains synthesized the multiple isoforms of bFGF protein. In one of the melanoma cell strains, no bFGF protein was detected using Western blot analysis. Although three of four melanoma cell strains expressed bFGF protein, this molecule does not appear to function as an autocrine growth factor, and expression of the bFGF protein was not a consistent alteration in all melanoma cell strains.

Metabolism of aldrin to dieldrin by rat skin following topical application

Metabolism of the pesticide aldrin to dieldrin in the rat was studied following topical and ip administration of 0.1-10 mg aldrin/kg body weight. When aldrin was applied topically to the dorsal skin at a dose of 10 mg/kg body weight, absorption was less efficient than after ip administration; lower blood levels of aldrin and dieldrin were seen and peak dieldrin levels were delayed. After ip administration of 1 or 10 mg aldrin/kg body weight, dieldrin was found at similar concentrations in the dorsal and ventral skin 7 hr later, whereas 7 hr after topical administration of 10 mg aldrin/kg, the dieldrin concentration in the skin at the dorsal site of application was four times higher than that at a ventral skin site. Similar differences in dieldrin concentrations between dorsal and ventral skin persisted throughout the 7-hr period following topical application. The results indicate that topically applied aldrin is metabolized to dieldrin in the skin during absorption, but the overall proportion of metabolism that takes place in the skin is small compared with the contribution of the liver. Dieldrin was not detected in the ventral skin remote from the application site 1 hr after topical application of aldrin, whereas a dieldrin concentration of 2.2 nmol/g was detected in the skin of the application site at this time; more than 99% of this dieldrin was probably formed locally by dermal metabolism of percutaneously absorbed aldrin. The efficiency of conversion of applied aldrin to dieldrin decreased with increasing aldrin dose in the range 0.1 to 10 mg/kg.