A New Sail-Backed Styracosternan (Dinosauria: Ornithopoda) from the Early Cretaceous of Morella,Spain

A new styracosternan ornithopod genus and species is here described based on a partial postcranial skeleton and an associated dentary tooth of a single specimen from the Arcillas de Morella Formation (Early Cretaceous, late Barremian) at the Morella locality, (Castellón, Spain). Morelladon beltrani gen. et sp. nov. is diagnosed by eight autapomorphic features. The set of autapomorphies includes: very elongated and vertical neural spines of the dorsal vertebrae, midline keel on ventral surface of the second to fourth sacral vertebrae restricted to the anterior half of the centrum, a posterodorsally inclined medial ridge on the postacetabular process of the ilium that meets its dorsal margin and distal end of the straight ischial shaft laterally expanded, among others. Phylogenetic analyses reveal that the new Iberian form is more closely related to its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, known from Western Europe, than to other Early Cretaceous Iberian styracosternans (Delapparentia turolensis and Proa valdearinnoensis). The recognition of Morelladon beltrani gen. et sp. nov. indicates that the Iberian Peninsula was home to a highly diverse medium to large bodied styracosternan assemblage during the Early Cretaceous.     

Past,present, and future research in bipolar lichen‐forming fungi and their photobionts

Compared to other organisms, such as vascular plants or mosses, lichen‐forming fungi have a high number of species occurring in both northern and southern hemispheres but are largely absent from intermediate, tropical latitudes. For instance, ca. 160 Antarctic species also occur in polar areas or mountainous temperate regions of the northern hemisphere. Early interpretations of this particular distribution pattern were made in terms of vicariance or long‐distance dispersal. However, it was not until the emergence of phylogenetics and the possibility of dating past diversification and colonization events that these initial hypotheses started to be evaluated. The premise of a relatively recent colonization of the southern hemisphere by boreal lichens through long‐distance dispersal has gained support in recent studies based on either the comparison of genetic affinities (i.e., tree topology) or more robust, statistical migratory models. Still, the scarcity of such studies and a concern that taxonomic concepts for bipolar lichens are often too broad preclude the generation of sound explanations on the mechanisms and origin of such fascinating disjunct distributions. This review provides an up‐to‐date overview of bipolar distributions in lichen‐forming fungi and their photobionts. Evidence provided by recent, molecular‐based studies as well as data on the type of lichen reproduction, dispersal ability, photobiont identity and availability, and habitat preferences are brought together to discuss how and when these distributions originated and their genetic footprints. Ideas for future prospects and research are also discussed.     

PINK1 and BECN1 relocalize at mitochondria-associated membranes during mitophagy and promote ER-mitochondria tethering and autophagosome formation

Mitophagy is a highly specialized process to remove dysfunctional or superfluous mitochondria through the macroautophagy/autophagy pathway, aimed at protecting cells from the damage of disordered mitochondrial metabolism and apoptosis induction. PINK1, a neuroprotective protein mutated in autosomal recessive Parkinson disease, has been implicated in the activation of mitophagy by selectively accumulating on depolarized mitochondria, and promoting PARK2/Parkin translocation to them. While these steps have been characterized in depth, less is known about the process and site of autophagosome formation upon mitophagic stimuli. A previous study reported that, in starvation-induced autophagy, the proautophagic protein BECN1/Beclin1 (which we previously showed to interact with PINK1) relocalizes at specific regions of contact between the endoplasmic reticulum (ER) and mitochondria called mitochondria-associated membranes (MAM), from which the autophagosome originates. Here we show that, following mitophagic stimuli, autophagosomes also form at MAM; moreover, endogenous PINK1 and BECN1 were both found to relocalize at MAM, where they promoted the enhancement of ER-mitochondria contact sites and the formation of omegasomes, that represent autophagosome precursors. PARK2 was also enhanced at MAM following mitophagy induction. However, PINK1 silencing impaired BECN1 enrichment at MAM independently of PARK2, suggesting a novel role for PINK1 in regulating mitophagy. MAM have been recently implicated in many key cellular events. In this light, the observed prevalent localization of PINK1 at MAM may well explain other neuroprotective activities of this protein, such as modulation of mitochondrial calcium levels, mitochondrial dynamics, and apoptosis.     

Neuroprotective role of quercetin in locomotor activities and cholinergic neurotransmission in rats experimentally demyelinated with ethidium bromide

Aim

The purpose of this study was to investigate whether the flavonoid quercetin can prevent alterations in the behavioral tests and of cholinergic neurotransmission in rats submitted to the ethidium bromide (EB) experimental demyelination model during events of demyelination and remyelination.

Main methods

Wistar rats were randomly distributed into four groups (20 animals per group): Control (pontine saline injection and treatment with ethanol), Querc (pontine saline injection and treatment with quercetin), EB (pontine 0.1% EB injection and treatment with ethanol), and EB + Querc (pontine 0.1% EB injection and treatment with quercetin). The groups Querc and Querc + EB were treated once daily with quercetin (50 mg/kg) diluted in 25% ethanol solution (1 ml/kg) and the animals of the control and EB groups were treated once daily with 25% ethanol solution (1 ml/kg). Two stages were observed: phase of demyelination (peak on day 7) and phase of remyelination (peak on day 21 post-injection). Behavioral tests (beam walking, foot fault and inclined plane test), acetylcholinesterase (AChE) activity and lipid peroxidation in pons, cerebellum, hippocampus, hypothalamus, striatum and cerebral cortex were measured.

Key findings

The quercetin promoted earlier locomotor recovery, suggesting that there was demyelination prevention or further remyelination velocity as well as it was able to prevent the inhibition of AChE activity and the increase of lipidic peroxidation, suggesting that this compound can protect cholinergic neurotransmission.

Significance

These results may contribute to a better understanding of the neuroprotective role of quercetin and the importance of an antioxidant diet in humans to provide benefits in neurodegenerative diseases such as MS.     

Mitochondrial DNA haplogroups and risk of new-onset diabetes among tacrolimus-treated renal transplanted patients

Background and aims

Tacrolimus (Tac) is an immunosuppressive drug widely used to avoid organ rejection. New-onset diabetes after transplantation (NODAT) is a major complication among transplanted patients who receive Tac. The increased risk for NODAT could be partly mediated by the effect of Tac on mitochondria from pancreatic beta-cells. Common and rare mitochondrial DNA variants have been linked to the risk of diabetes. Our aim was to determine whether mtDNA polymorphisms/haplogroups were associated with NODAT in Tac-treated kidney transplanted.

Methods

Seven polymorphisms that define the common European haplogroups were determined in 115 NODAT and 197 no-NODAT patients.

Results

Haplogroup H was significantly more frequent in the NODAT group (50% vs. 35%; p = 0.01, OR = 1.82). There was no difference between patients without and with (n = 106) D2M prior to the transplant.

Conclusions

Mitochondrial haplogroup H was associated with the risk for NODAT among Tac-treated transplanted patients. The reported differences between the mtDNA variants could explain the increased NODAT-risk among H-patients.     

Circadian Locomotor Activity Under Artificial Light in the Freshwater Crab Pseudothelphusa americana

Long-term recordings of locomotor activity were obtained from intact freshwater crabs, Pseudothelphusa americana in constant darkness (DD), constant light (LL) and different light-dark (LD) protocols. Bimodal rhythms were typically observed in this crab when subjected to DD or LD, with bouts of activity anticipating lights-on and lights-off, respectively. Freerunning circadian rhythms were expressed in both DD and LL for longer than 30 days. In DD, we observed that some animals presented different period lengths for each activity component. During LL, activity was primarily unimodal, however spontaneous splitting of the rhythms were observed in some animals. When activity was recorded under artificial long days, the morning bouts maintained their phase relationship but the evening bouts changed their phase relationship with the Zeitgeber. Our results indicate that, bimodal locomotor activity rhythm in the crab Pseudothelphusa americana is variable among organisms. The characteristics of phase relationship with LD and responses to LL for morning and evening bouts, suggest that, locomotor activity could be driven by multiple oscillators, and that coupling between these oscillators may be regulated by light.     

Effect of propranolol on glycerol induced acute renal failure in rats

The effect produced by propranolol, administered for a prolonged period of time and in large doses, on renal function in rats has been studied, as well as the modifications induced by this treatment in an experimental model of acute renal failure, and the effects of a single dose of propranolol given 1 hour before provoking failure. Propranolol, administered chronically, causes sodium and water retention and increases creatinine clearance. Acute renal failure induced by glycerol in rats treated for 7 days with propranolol is less severe than the one produced in untreated animals. In this ARF model, a single dose of propranolol does not seem to have a protective effect.     

Effectiveness of Partial Sedation to Reduce Stress in Captured Mule Deer

Information garnered from the capture and handling of free-ranging animals helps advance understanding of wildlife ecology and can aid in decisions on wildlife management. Unfortunately, animals may experience increased levels of stress, injuries, and death resulting from captures (e.g., exertional myopathy, trauma). Partial sedation is a technique proposed to alleviate stress in animals during capture, yet efficacy of partial sedation for reducing stress and promoting survival post-capture remains unclear. We evaluated the effects of partial sedation on physiological, biochemical, and behavioral indicators of acute stress and probability of survival post-capture for mule deer (Odocoileus hemionus) that were captured via helicopter net-gunning in the eastern Greater Yellowstone Ecosystem, Wyoming, USA. We administered 10–30 mg of midazolam and 15 mg of azaperone intramuscularly (IM) to 32 mule deer in 2016 and 53 mule deer in 2017, and maintained a control group (captured but not sedated) of 38 mule deer in 2016 and 54 mule deer in 2017. To evaluate indicators of acute stress, we measured heart rate, blood-oxygen saturation, body temperature, respiration rate, and levels of serum cortisol. We recorded number of kicks and vocalizations of deer during handling and evaluated behavior during release. We also measured levels of fecal glucocorticoids as an indicator of baseline stress. Midazolam and azaperone did not reduce physiological, biochemical, or behavioral indicators of acute stress or influence probability of survival post-capture. Mule deer that were administered midazolam and azaperone, however, were more likely to hesitate, stumble or fall, and walk during release compared with individuals in the control group, which were more likely to trot, stot, or run without stumbling or falling. Our findings suggest that midazolam (10–30 mg IM) and azaperone (15 mg IM) may not yield physiological or demographic benefits for captured mule deer as previously assumed and may pose adverse effects that can complicate safety for captured animals, including drug-induced lethargy. Although we failed to find efficacy of midazolam and azaperone as a method for reducing stress in captured mule deer, the efficacy of midazolam and azaperone or other combinations of partial sedatives in reducing stress may depend on the dose of tranquilizer, study animal, capture setting, and how stress is defined. © 2020 The Wildlife Society.