Protein kinase D1 inhibition interferes with mitosis progression

Protein kinase D1 (PKD1) plays a vital role in signal transduction, cell proliferation, membrane trafficking, and cancer; however, the majority of the studies up to date had centered primarily on PKD1 functions in interphase, very little is known about its role during cell division. We previously demonstrated that during mitosis PKD1 is activated and associated with centrosomes, spindles, and midbodies. However, these observations did not address whether PKD1 was associated with mitosis regulation. Accordingly, we used rapidly acting PKD-specific inhibitors to examine the contribution of PKD1 the sequence of events in mitosis. We found that although PKD1 overexpression did not affect mitosis progression, suppression of its catalytic activity by two structurally unrelated inhibitors (kb NB 142-70 and CRT 0066101) induced a significant delay in metaphase to anaphase transition time. PKD1 inhibition during mitosis also produced the appearance of abnormal spindles, defects in chromosome alignment, and segregation as well as apoptosis. Thus, these observations indicate that PKD1 activity is associated with mitosis regulation.     

Rapid shifts in the thermal sensitivity of growth but not development rate causes temperature–size response variability during ontogeny in arthropods

Size at maturity in ectotherms commonly declines with warming. This near‐universal phenomenon, formalised as the temperature–size rule, has been observed in over 80% of tested species, from bacteria to fish. The proximate cause has been attributed to the greater temperature dependence of development rate than growth rate, causing individuals to develop earlier but mature smaller in the warm. However, few studies have examined the ontogenetic progression of the temperature–size response at high resolution. Using marine planktonic copepods, we experimentally determined the progression of the temperature–size response over ontogeny. Temperature–size responses were not generated gradually from egg to adult, contrary to the predictions of a naïve model in which development rate was assumed to be more temperature‐dependent than growth rate, and the difference in the temperature dependence of these two rates remained constant over ontogeny. Instead, the ontogenetic progression of the temperature–size response in experimental animals was highly episodic, indicating rapid changes in the extent to which growth and development rates are thermally decoupled. The strongest temperature–size responses occurred temporally mid‐way through ontogeny, corresponding with the point at which individuals reached between ~5 and 25% of their adult mass. Using the copepod Oithona nana, we show that the temperature‐dependence of growth rate varied substantially throughout ontogeny, whereas the temperature dependence of development rate remained constant. The temperature‐dependence of growth rate even exceeded that of development rate in some life stages, leading to a weakening of the temperature–size response. Our analyses of arthropod temperature–size responses from the literature, including crustaceans and insects, support these conclusions more broadly. Overall, our findings provide a better understanding of how the temperature–size rule is produced over ontogeny. Whereas we find support for the generality of developmental rate isomorphy in arthropods (shared temperature dependence of development rate across life stages), this concept appears not to apply to growth rates.     

Phylogeny of the Augochlora clade with the description of four new species (Hymenoptera,Apoidea)

The Augochlora clade includes four genera: Augochlora Smith, Augochlorella Sandhouse, Ceratalictus Moure, and Pereirapis Moure. This is one of the richest and most widespread groups of Augochlorini bees. There are about 150 species, which occur from Argentina to Canada. The species of Augochlora clade are considered solitary to facultatively social, except Ceratalictus for which nothing is known. Wood nesting behavior arose once in the clade, in Augochlora sensu strictu. The objective of this study is to describe four new species and to present a revised phylogenetic analysis of the Augochlora clade for the placement of these species. The morphological matrix comprised 77 characters and 42 terminals, and resulted in two most parsimonious trees. The monophyly of the Augochlora clade is corroborated. Ceratalictus and Pereirapis are considered as sister groups and Ceratalictus inflexus sp. nov. came as sister to other species of Ceratalictus. Augochlora and Augochlorella are monophyletic and sister groups. Both extant subgenera of Augochlora were corroborated as monophyletic. Augochlorella comis is considered as sister group to the rest of Augochlorella species. All Augochlorella new species described belong to the Augochlorella ephyra group. Augochlorella kelliae sp. nov. is phylogenetically related to Augochlorella una. Augochlorella procliva sp. nov. and Augochlorella mavricera sp. nov. constitute a clade with Augochlorella acarinata. Including the new species, Augochlorella has 19 species and Ceratalictus 11 species. A revised key for species of Augochlorella and Ceratalictus is also presented in the Supplementary Information.     

Expresión sexual y regulación de la sexualidad en residencias de personas mayores

Objectives

The study had three objectives: (a) To determine how staff perceives the frequency of different sexual expressions in long-term care facilities for older people; (2) to quantify policies aimed at guaranteeing residents’ sexual rights in such institutions, and (3) to determine factors influencing the presence of these kind of policies.

Palmitic Acid-Induced NAD+ Depletion is Associated with the Reduced Function of SIRT1 and Increased Expression of BACE1 in Hippocampal Neurons

Increased levels of circulating fatty acids, such as palmitic acid (PA), are associated with the development of obesity, insulin resistance, type-2 diabetes and metabolic syndrome. Furthermore, these diseases are linked to an increased risk of cancer, cardiovascular diseases, mild cognitive impairment and even Alzheimer’s disease (AD). However, the precise actions of elevated PA levels on neurons and their association with neuronal metabolic disruption that leads to the expression of pathological markers of AD, such as the overproduction and accumulation of the amyloid-β peptide, represent an area of intense investigation. A possible molecular mechanism involved in the effects of PA may be through dysfunction of the NAD⁺ sensor enzyme, SIRT1. Therefore, the aim of the present study was to analyze the relationship between the effects of PA metabolism on the function of SIRT1 and the upregulation of BACE1 in cultured hippocampal neurons. PA reduced the total amount of NAD⁺ in neurons that caused an increase in p65 K310 acetylation due to inhibition of SIRT1 activity and low protein content. Furthermore, BACE1 protein and its activity were increased, and BACE1 was relocated in neurites after PA exposure.

     

Manipulation of oxidative stress responses as a strategy to generate stress-tolerant crops. From damage to signaling to tolerance

Plants exposed to hostile environmental conditions such as drought or extreme temperatures usually undergo oxidative stress, which has long been assumed to significantly contribute to the damage suffered by the organism. Reactive oxygen species (ROS) overproduced under stress conditions were proposed to destroy membrane lipids and to inactivate proteins and photosystems, ultimately leading to cell death. Accordingly, considerable effort has been devoted, over the years, to improve stress tolerance by strengthening antioxidant and dissipative mechanisms. Although the notion that ROS cause indiscriminate damage in vivo has been progressively replaced by the alternate concept that they act as signaling molecules directing critical plant developmental and environmental responses including cell death, the induction of genes encoding antioxidant activities is commonplace under many environmental stresses, suggesting that their manipulation still offers promise. The features and consequences of ROS effects depend on the balance between various interacting pathways including ROS synthesis and scavenging, energy dissipation, conjugative reactions, and eventually reductive repair. They represent many possibilities for genetic manipulation. We report, herein, a comprehensive survey of transgenic plants in which components of the ROS-associated pathways were overexpressed, and of the stress phenotypes displayed by the corresponding transformants. Genetic engineering of different stages of ROS metabolism such as synthesis, scavenging, and reductive repair revealed a strong correlation between down-regulation of ROS levels and increased stress tolerance in plants grown under controlled conditions. Field assays are scarce, and are eagerly required to assess the possible application of this strategy to agriculture.     

Daily rhythms of leukocytes populations,biochemical and enzymatic blood parameters in a carnivorous freshwater catfish (Lophiosilurus alexandri)

The aim of this study was to investigate the daily rhythms of hematological, biochemical and enzymatic parameters of the blood of a nocturnal model of fish (Lophiosilurus alexandri) bred in the laboratory (F1). Thirty-six juveniles were stocked in six tanks of a recirculation aquaculture system for 20 days. The fish were exposed to a light:dark cycle of 12:12 h and were fed 1% of biomass twice a day with commercial diet. The daily rhythms of hematological, biochemical and enzymatic parameters were then measured at six sampling times “zeitgeber time = ZT” at four-hour intervals under light:dark 12:12 h (lights on = ZT0, at 8.00 a.m). No differences were observed to alkaline phosphatase, glucose, cortisol, aspartate aminotransferase, superoxide dismutase, total protein and hematocrit (p > 0.05). However, white blood cell count, Lymphocytes (LYN), Neutrophils (NEU), Eosinophil and Neutrophils to Lymphocytes ratio were significant different between sample times (p < 0.05). Also, a significant difference in alanine transaminase was observed, with a peak of production at nighttime. In contrast, glutathione peroxidase peaked at 8:00. Uric acid, magnesium and Calcium (Ca⁺⁺) showed statistically significant differences (p < 0.05). A significant difference was observed (p < 0.05), with a peak of albumin at 08:00 and triglycerides at 12:00, while cholesterol was low (p < 0.05) at 08:00 and higher from 12:00 to 04:00. Cosinor analysis revealed also rhythmicity to SOD, UA, Mg and Ca⁺⁺, ALB and CHO (p < 0.05). In conclusion, the time of day must be considered a key factor when using blood parameters as biomarkers for disease, health and welfare in the L. alexandri aquaculture.