The kidney of a teleost, Spinachia spinachia II. Histochemical identification of sialic acid-containing glycoprotein and fine structure of mucus secreting cells

Kidney cells of the marine stickleback Spinachia have been studied with histochemical methods for the demonstration of glycoconjugates. The fine structure of epithelial cells is described. Mucus threads in the nephronic tubule of sexually mature males consist of neutral glycoprotein which corresponds with the secretory granules in proximal tubule segment II cells. Large lysosome-like inclusions, which also react with PAS, are present in many P II cells. All cells of the collecting duct epithelium differentiate into mucous cells in male Spinachia. The nature of their secretory products, which are well preserved by freeze-drying, is discussed. Sialylated glycoprotein is present in mucus granules and sulphated glycoprotein can be demonstrated at the apex of collecting duct cells. Collecting duct cell mucus can be digested with testicular hyaluronidase indicating that proteoglycans may be involved in the structure of macromolecules. The observations are compared with studies of mucus production in the urinary apparatus of several other vertebrates.     

Genome‐wide SNP analysis reveals an increase in adaptive genetic variation through selective breeding of coral

Marine heat waves are increasing in magnitude, duration, and frequency as a result of climate change and are the principal global driver of mortality in reef‐building corals. Resilience‐based genetic management may increase coral heat tolerance, but it is unclear how temperature responses are regulated at the genome level and thus how corals may adapt to warming naturally or through selective breeding. Here we combine phenotypic, pedigree, and genomic marker data from colonies sourced from a warm reef on the Great Barrier Reef reproductively crossed with conspecific colonies from a cooler reef to produce combinations of warm purebreds and warm‐cool hybrid larvae and juveniles. Interpopulation breeding created significantly greater genetic diversity across the coral genome compared to breeding between populations and maintained diversity in key regions associated with heat tolerance and fitness. High‐density genome‐wide scans of single nucleotide polymorphisms (SNPs) identified alleles significantly associated with larval families reared at 27.5°C (87–2,224 loci), including loci putatively associated with proteins involved in responses to heat stress (cell membrane formation, metabolism, and immune responses). Underlying genetics of these families explained 43% of PCoA multilocus variation in survival, growth, and bleaching responses at 27.5°C and 31°C at the juvenile stage. Genetic marker contribution to total variation in fitness traits (narrow‐sense heritability) was high for survival but not for growth and bleaching in juveniles, with heritability of these traits being higher at 31°C relative to 27.5°C. While based on only a limited number of crosses, the mechanistic understanding presented here demonstrates that allele frequencies are affected by one generation of selective breeding, key information for the assessments of genetic intervention feasibility and modelling of reef futures.     

Pattern and pace of morphological change due to variable human impact: the case of Japanese macaques

Primates - Human impact influences morphological variation in animals, as documented in many captive and domestic animal populations. However, there are different levels of human impact, and their...     

PA28α overexpressing female mice maintain exploratory behavior and capacity to prevent protein aggregation in hippocampus as they age

With age, protein damage accumulates and increases the risk of age‐related diseases. The proteasome activator PA28αβ is involved in protein damage clearance during early embryogenesis and has demonstrated protective effects against proteinopathy. We have recently discovered that adult female mice overexpressing PA28α (PA28αOE) have enhanced learning and memory, and protein extracts from their hippocampi prevent aggregation more efficiently than wild type. In this study, we investigated the effect of overexpressing PA28α on aging using C57BL/6N×BALB/c F2 hybrid mice. We found that the hippocampal anti‐aggregation effect was maintained in young adult (7 months) to middle‐aged (15 months) and old (22 months) PA28αOE females. While the PA28αOE influence on learning and memory gradually decreased with aging, old PA28αOE females did not display the typical drop in explorative behavior—a behavioral hallmark of aging—but were as explorative as young mice. PA28αOE lowered PA28‐dependent proteasome capacity in both heart and hippocampus, and there was no indication of lower protein damage load in PA28αOE. The life span of PA28αOE was also similar to wild type. In both wild type and PA28αOE, PA28‐dependent proteasome capacity increased with aging in the heart, while 26S and 20S proteasome capacities were unchanged in the timepoints analyzed. Thus, PA28αOE females exhibit improved hippocampal ability to prevent aggregation throughout life and enhanced cognitive capabilities with different behavioral outcomes dependent on age; improved memory at early age and a youth‐like exploration at old age. The cognitive effects of PA28αβ combined with its anti‐aggregation molecular effect highlight the therapeutical potential of PA28αβ in combating proteinopathies.     

Assessing the contribution of bacteria to the heat tolerance of experimentally evolved coral photosymbionts

Coral reefs are extremely vulnerable to ocean warming, which triggers coral bleaching—the loss of endosymbiotic microalgae (Symbiodiniaceae) from coral tissues, often leading to death. To enhance coral climate resilience, the symbiont, Cladocopium proliferum was experimentally evolved for >10 years under elevated temperatures resulting in increased heat tolerance. Bacterial 16S rRNA gene metabarcoding showed the composition of intra- and extracellular bacterial communities of heat-evolved strains was significantly different from that of wild-type strains, suggesting bacteria responded to elevated temperatures, and may even play a role in C. proliferum thermal tolerance. To assess whether microbiome transplantation could enhance heat tolerance of the sensitive wild-type C. proliferum, we transplanted bacterial communities from heat-evolved to the wild-type strain and subjected it to acute heat stress. Microbiome transplantation resulted in the incorporation of only 30 low-abundance strains into the microbiome of wild-type cultures, while the relative abundance of 14 pre-existing strains doubled in inoculated versus uninoculated samples. Inoculation with either wild-type or heat-evolved bacterial communities boosted C. proliferum growth, although no difference in heat tolerance was observed between the two inoculation treatments. This study provides evidence that Symbiodiniaceae-associated bacterial communities respond to heat selection and may contribute to coral adaptation to climate change.     

METAL UPTAKE AND ALLOCATION IN TREES GROWN ON CONTAMINATED LAND: IMPLICATIONS FOR BIOMASS PRODUCTION

Phytostabilization aims to reduce environmental and health risks arising from contaminated soil. To be economically attractive, plants used for phytostabilization should produce valuable biomass. This study investigated the biomass production and metal allocation to foliage and wood of willow (Salix viminalis L.), poplar (Populus monviso), birch (Betula pendula), and oak (Quercus robur) on five different soils contaminated with trace elements (TE), with varying high concentrations of Cu, Zn, Cd, and Pb as well as an uncontaminated control soil. In the treatment soils, the biomass was reduced in all species except oak. There was a significant negative correlation between biomass and foliar Cd and Zn concentrations, reaching up to 15 mg Cd kg^?1 and 2000 mg Zn kg ^?1 in willow leaves. Lead was the only TE with higher wood than foliage concentrations. The highest Pb accumulation occurred in birch with up to 135 mg kg ^?1 in wood and 78 mg kg ^?1 in foliage. Birch could be suitable for phytostabilization of soils with high Cd and Zn but low Pb concentrations, while poplars and willows could be used to stabilise soils with high Cu and Pb and low Zn and Cd concentrations.     

Why People Do,or Do Not,Immediately Contact Emergency Medical Services following the Onset of Acute Stroke: Qualitative Interview Study

Objectives

To identify the reasons why individuals contact, or delay contacting, emergency medical services in response to stroke symptoms.

Design

Qualitative interview study with a purposive sample of stroke patients and witnesses, selected according to method of accessing medical care and the time taken to do so. Data were analysed using the Framework approach.

Setting

Area covered by three acute stroke units in the north east of England.

Participants

Nineteen stroke patients and 26 witnesses who had called for help following the onset of stroke symptoms.

Results

Factors influencing who called emergency medical services and when they called included stroke severity, how people made sense of symptoms and their level of motivation to seek help. Fear of the consequences of stroke, including future dependence or disruption to family life, previous negative experience of hospitals, or involving a friend or relations in the decision to access medical services, all resulted in delayed admission. Lack of knowledge of stroke symptoms was also an important determinant. Perceptions of the remit of medical services were a major cause of delays in admission, with many people believing the most appropriate action was to telephone their GP. Variations in the response of primary care teams to acute stroke symptoms were also evident.

Conclusions

The factors influencing help-seeking decisions are complex. There remains a need to improve recognition by patients, witnesses and health care staff of the need to treat stroke as a medical emergency by calling emergency medical services, as well as increasing knowledge of symptoms of stroke among patients and potential witnesses. Fear, denial and reticence to impose on others hinders the process of seeking help and will need addressing specifically with appropriate interventions. Variability in how primary care services respond to stroke needs further investigation to inform interventions to promote best practice.

Trial Registration

UK Clinical Research Network UKCRN 6590