The effects of portacaval shunt upon hepatic cholesterol synthesis and cyclic AMP in dogs and baboons

Hepatic cholesterol synthesis, hepatic cyclic AMP, and portal and peripheral insulin and glucagon levels were investigated in nine dogs and three baboons after complete portacaval shunt. Cholesterol synthesis as measured with acetate incorporation was reduced in both species. Hepatic cyclic AMP increased in dogs. Changes in portal and systemic insulin were inconsistent, but hyper-glucagonemia occurred regularly. Diminished hepatic cholesterol synthesis is apparently one factor, although probably not the only one, in the antilipidemic effect of portacaval shunt. This altered cholesterol metabolism may be due to a change in the hormonal environment of the liver caused by portal diversion

The effect of splanchnic viscera removal upon canine liver regeneration

The influence of portal blood factors on canine liver regeneration was studied with graded nonhepatic splanchnic evisceration, coupled with 44 and 72 per cent hepatectomies. In one type of experiment, the pancreas was retained while the rest of the intra-abdominal gastrointestinal tract was removed. In a second variety, total pancreatectomy was performed with preservation of the intra-abdominal organs. In a third kind of experiment, total nonhepatic splanchnic evisceration was performed. Liver regeneration after hepatectomy was decreased by all three kinds of viscera removed as judged by deoxyribonucleic acid synthesis, autoradiography and mitotic index. Pancreatectomy and nonpancreatic splanchnic evisceration caused almost equal decreases in the regenerative response. Total nonhepatic splanchnic evisceration essentially halted regeneration during the first three postoperative days and intraportal infusions of insulin or glucagon, or both together, did not reverse this effect. The decrease in liver membrane bound adenyl cyclase activity and biphasic change in liver cyclic 3',5'-adenosine monophosphate concentrations normally seen partial hepatectomy was disrupted after the various eviscerations. Adenyl cyclase activity and cyclic monophosphate concentrations tended to be higher than normal in the eviscerated dogs. These observations provide more support for our previously proposed hypothesis that control of liver regeneration is by multiple factors. Pancreatic hormones are important modifiers of this response but by no means exercise exclusive control. Other substances of gastrointestinal origin, presumably including hormones and nutrient supply apparently play important specific roles. The volume of portal flow is a secondary and nonspecific, but possibly significant, factor

The dual dust chemistries of planetary nebulae with [WCL] central stars

The rather rare class of central stars of planetary nebulae that show very low-excitation Wolf–Rayet spectra has been a subject of great interest, particularly in the infrared, since its discovery in the late 1960s. Further peculiarities have been found with the advent of infrared spectroscopy from ISO. Notably, these objects simultaneously betray the presence of regions of carbon-rich and oxygen-rich dust chemistry. We compare and contrast complete ISO spectra between 2 and 200 μm of a sample of six [WC8] to [WC11] central stars, finding many similarities. Among this sample, one star provides strong evidence of quasi-periodic light variations, suggestive of a dust cloud orbiting in a plane from which we view the system

Altered expression of glutamate signaling, growth factor, and glia genes in the locus coeruleus of patients with major depression.

Several studies have proposed that brain glutamate signaling abnormalities and glial pathology have a role in the etiology of major depressive disorder (MDD). These conclusions were primarily drawn from post-mortem studies in which forebrain brain regions were examined. The locus coeruleus (LC) is the primary source of extensive noradrenergic innervation of the forebrain and as such exerts a powerful regulatory role over cognitive and affective functions, which are dysregulated in MDD. Furthermore, altered noradrenergic neurotransmission is associated with depressive symptoms and is thought to have a role in the pathophysiology of MDD. In the present study we used laser-capture microdissection (LCM) to selectively harvest LC tissue from post-mortem brains of MDD patients, patients with bipolar disorder (BPD) and from psychiatrically normal subjects. Using microarray technology we examined global patterns of gene expression. Differential mRNA expression of select candidate genes was then interrogated using quantitative real-time PCR (qPCR) and in situ hybridization (ISH). Our findings reveal multiple signaling pathway alterations in the LC of MDD but not BPD subjects. These include glutamate signaling genes, SLC1A2, SLC1A3 and GLUL, growth factor genes FGFR3 and TrkB, and several genes exclusively expressed in astroglia. Our data extend previous findings of altered glutamate, astroglial and growth factor functions in MDD for the first time to the brainstem. These findings indicate that such alterations: (1) are unique to MDD and distinguishable from BPD, and (2) affect multiple brain regions, suggesting a whole-brain dysregulation of such functions

Violation of the London Law and Onsager-Feynman quantization in multicomponent superconductors

Non-classical response to rotation is a hallmark of quantum ordered states such as superconductors and superfluids. The rotational responses of all currently known single-component "super" states of matter (superconductors, superfluids and supersolids) are largely described by two fundamental principles and fall into two categories according to whether the systems are composed of charged or neutral particles: the London law relating the angular velocity to a subsequently established magnetic field and the Onsager-Feynman quantization of superfluid velocity. These laws are theoretically shown to be violated in a two-component superconductor such as the projected liquid metallic states of hydrogen and deuterium at high pressures. The rotational responses of liquid metallic hydrogen or deuterium identify them as a new class of dissipationless states; they also directly point to a particular experimental route for verification of their existence.Comment: Nature Physics in print. This is an early version of the paper. The final version will be posted 6 months after its publication Nature Physics, according to the journal polic

Bayesian photometric redshifts of blended sources

Photometric redshifts are necessary for enabling large-scale multicolour galaxy surveys to interpret their data and constrain cosmological parameters. While the increased depth of future surveys such as the Large Synoptic Survey Telescope (LSST) will produce higher precision constraints, it will also increase the fraction of sources that are blended. In this paper, we present a Bayesian photometric redshift (BPZ) method for blended sources with an arbitrary number of intrinsic components. This method generalizes existing template-based BPZ methods, and produces joint posterior distributions for the component redshifts that allow uncertainties to be propagated in a principled way. Using Bayesian model comparison, we infer the probability that a source is blended and the number of components that it contains. We extend our formalism to the case where sources are blended in some bands and resolved in others. Applying this to the combination of LSST- and Euclid-like surveys, we find that the addition of resolved photometry results in a significant improvement in the reduction of outliers over the fully blended case. We make available blendz, a Python implementation of our method

Explaining unexplained pain to fibromyalgia patients: finding a narrative that is acceptable to patients and provides a rationale for evidence based interventions

As the cause of fibromyalgia is controversial, communicating with patients can be challenging, particularly if the patient adopts the narrative ‘I am damaged and so I need a more powerful pain killer’. Research shows that providing patients with alternative narratives can be helpful, but it remains unclear what particular narratives are most acceptable to patients and at the same time provide a rationale for evidence based psychological and exercise interventions. This article described the development of a new narrative and the written comments made about the narrative by fibromyalgia patients. The narrative derives from a complexity theory model and provides an alternative to biogenic and psychogenic models. The model was presented to 15 patients whose comments about comprehensibility led to the final format of the narrative. In the final form, the body is presented as ‘a very, very clever computer’ where fibromyalgia is caused by a software rather than a hardware problem. The software problem is caused by the body adapting when people have to ‘keep going’ despite ‘stop signals’, such as pain and fatigue. The narrative provides a rationale for engaging in psychological and exercise interventions as a way of correcting the body’s software. This way of explaining fibromyalgia was evaluated by a further 25 patients attending a 7-week ‘body reprogramming’ intervention, where the therapy was presented as correcting the body’s software, and included both exercise and psychological components. Attendance at the course was 85%. Thematic analysis of written patient feedback collected after each session showed that patients found the model believable and informative, it provided hope and was empowering. Patients also indicated that they had started to implement lifestyle change with perceived benefit. Fibromyalgia patients appear to respond positively to a technology-derived narrative based on the analogy of the body as a computer

GROWTH-STIMULATING FACTOR IN REGENERATING CANINE LIVER

Extracts from dog livers which had been regenerating for 24, 48, and 72 h after hepatectomy were infused for 6 h into the left portal vein of animals which had fresh portacaval shunts (Eck fistula) and which were killed 2 and 3 days later. The brief exposure to the 48-h and especially the 72-h regenerating liver extracts induced a delayed proliferative response predominantly in the left liver lobes, with a slight spillover effect to the right liver lobes but none to the kidney. The response reached its peak 3 days later. In the left but not the right liver lobes, both the 48-h and the 72-h regenerating liver extract reversed the atrophy ordinarily caused by Eck fistula in 3 days and partly prevented the ultrastructural hepatocyte deterioration characteristic of Eck fistula. The active liver extracts apparently contained a growth-control factor or factors which is (are) not insulin or glucagon. © 1979

Evidence of potential establishment of pink salmon Oncorhynchus gorbuscha in Scotland.

In spring 2022, pink salmon Oncorhynchus gorbuscha smolts were recorded in the UK. Fish were caught in the Rivers Thurso and Oykel in Scotland between 13 and 17 March. To the authors' knowledge, this is the first observation of O. gorbuscha smolts in Europe outside the Scandinavian and Kola peninsulas, including other tributaries of the White and Barents Seas. It also provides evidence of successful spawning in 2021 and completion of the freshwater phase of the life cycle, and indicates the possibility for potential establishment of an O. gorbuscha population in Great Britain

Models of Star-Planet Magnetic Interaction

Magnetic interactions between a planet and its environment are known to lead to phenomena such as aurorae and shocks in the solar system. The large number of close-in exoplanets that were discovered triggered a renewed interest in magnetic interactions in star-planet systems. Multiple other magnetic effects were then unveiled, such as planet inflation or heating, planet migration, planetary material escape, and even modification of the host star properties. We review here the recent efforts in modelling and understanding magnetic interactions between stars and planets in the context of compact systems. We first provide simple estimates of the effects of magnetic interactions and then detail analytical and numerical models for different representative scenarii. We finally lay out a series of future developments that are needed today to better understand and constrain these fascinating interactions.Comment: 23 pages, 10 figures, accepted as a chapter in the Handbook of Exoplanet