Incidence and risk factors for mortality and end-stage renal disease in people with type 2 diabetes and diabetic kidney disease: a population-based cohort study in the UK

INTRODUCTION

We aimed to determine the incidence of, and risk factors for all-cause/cardiovascular disease (CVD) mortality, and end-stage renal disease (ESRD) among people with type 2 diabetes with/without diabetic kidney disease (DKD) in the UK general population.

RESEARCH DESIGN AND METHODS

We undertook a population-based cohort study using primary care UK electronic health records. We followed 8413 people with type 2 diabetes and DKD and a matched comparison cohort of people with type 2 diabetes without DKD. Risk factors for all-cause/CVD mortality (using both cohorts) and ESRD (DKD cohort only) were evaluated by estimating HRs with 95% CIs using Cox regression.

RESULTS

In the DKD cohort (mean age 66.7 years, 62.4% male), incidence rates per 1000 person-years were 50.3 (all-cause mortality), 8.0 (CVD mortality) and 6.9 (ESRD). HRs (95% CIs; DKD vs comparison cohort) were 1.49 (1.35 to 1.64) for all-cause mortality and 1.60 (1.24 to 2.05) for CVD mortality. In general, higher all-cause mortality risks were seen with older age, underweight (body mass index <20 kg/m²), reduced renal function, and cardiovascular/liver disease, and lower risks were seen with being female or overweight. In the DKD cohort, higher risks of ESRD were seen with reduced renal function at baseline, high material deprivation, cancer and non-insulin glucose-lowering drugs, and a lower risk was seen with overweight (≥25 kg/m²).

CONCLUSIONS

Annually, one death will occur among every 20 people with type 2 diabetes and DKD. The identified risk factors in this study will help identify people with type 2 diabetes at most risk of death and progression of kidney disease, and help to direct effective management strategies.

Rethomics: An R framework to analyse high-throughput behavioural data

The recent development of automatised methods to score various behaviours on a large number of animals provides biologists with an unprecedented set of tools to decipher these complex phenotypes. Analysing such data comes with several challenges that are largely shared across acquisition platform and paradigms. Here, we present rethomics, a set of R packages that unifies the analysis of behavioural datasets in an efficient and flexible manner. rethomics offers a computational solution to storing, manipulating and visualising large amounts of behavioural data. We propose it as a tool to bridge the gap between behavioural biology and data sciences, thus connecting computational and behavioural scientists. rethomics comes with a extensive documentation as well as a set of both practical and theoretical tutorials (available at https://rethomics.github.io).

Technology or ecology? New tools to assess cognitive judgement bias in mice

Cognitive judgement bias tests have become important new tools for the assessment of animal emotions. They allow for the inference of an animal's emotional state based on ambiguous cue interpretations. As mice are the predominantly used animal model for cognitive and behavioural neuroscience, research in this field would considerably benefit from the development of suitable judgement bias tests for this species. Against this background, we aimed to implement two different active choice cognitive judgement bias paradigms for mice in a methodological study. For this purpose, two experiments were conducted: in experiment I, an automated, vision-based touchscreen technique was applied, allowing for the direct translation of tasks from rodents to humans and vice versa. Experiment II comprised a task relying on more ecologically relevant cues in form of tunnels of different lengths. While the touchscreen task was characterized by automation-related advantages such as the possibility to present many trials per session and a high convenience for the experimenter, the tunnel task was learned faster by the mice. In both tests, however, the response to the trained and ambiguous conditions resulted in a graded curve, the basic requirement for proving task validity. Thus, both the translational touchscreen task as well as the ecologically more relevant tunnel task could successfully be implemented and provide new tools for the future assessment of cognitive judgement biases in mice.

Ethoscopes: An open platform for high-throughput ethomics

Here, we present the use of ethoscopes, which are machines for high-throughput analysis of behavior in Drosophila and other animals. Ethoscopes provide a software and hardware solution that is reproducible and easily scalable. They perform, in real-time, tracking and profiling of behavior by using a supervised machine learning algorithm, are able to deliver behaviorally triggered stimuli to flies in a feedback-loop mode, and are highly customizable and open source. Ethoscopes can be built easily by using 3D printing technology and rely on Raspberry Pi microcomputers and Arduino boards to provide affordable and flexible hardware. All software and construction specifications are available at http://lab.gilest.ro/ethoscope.

Drosophila WASH is required for integrin-mediated cell adhesion, cell motility and lysosomal neutralization

The Wiskott-Aldrich syndrome protein and SCAR homolog (WASH; also known as Washout in flies) is a conserved actin-nucleation-promoting factor controlling Arp2/3 complex activity in endosomal sorting and recycling. Previous studies have identified WASH as an essential regulator in Drosophila development. Here, we show that homozygous wash mutant flies are viable and fertile. We demonstrate that Drosophila WASH has conserved functions in integrin receptor recycling and lysosome neutralization. WASH generates actin patches on endosomes and lysosomes, thereby mediating both aforementioned functions. Consistently, loss of WASH function results in cell spreading and cell migration defects of macrophages, and an increased lysosomal acidification that affects efficient phagocytic and autophagic clearance. WASH physically interacts with the vacuolar (V)-ATPase subunit Vha55 that is crucial to establish and maintain lysosome acidification. As a consequence, starved flies that lack WASH function show a dramatic increase in acidic autolysosomes, causing a reduced lifespan. Thus, our data highlight a conserved role for WASH in the endocytic sorting and recycling of membrane proteins, such as integrins and the V-ATPase, that increase the likelihood of survival under nutrient deprivation.

Identification of a novel interaction between integrin beta1 and 14-3-3beta

Integrins are cell surface receptors for extracellular matrix, which play important roles in a variety of biological processes. 14-3-3 proteins are a highly conserved family of cytoplasmic proteins that associate with several intracellular signaling molecules in regulation of various cellular functions. Here, we report identification of an interaction between the integrin beta1 cytoplasmic domain and 14-3-3beta by using the yeast two-hybrid screen. Like several other proteins, the integrin beta1 cytoplasmic domain associated with 14-3-3beta by a non-phosphoserine mechanism. The 14-3-3beta/integrin beta1 interaction was confirmed by in vitro binding assays as well as co-precipitation in vivo. Furthermore, we found that 14-3-3beta co-localized with integrin beta1 during the early stage of cell spreading on fibronectin, suggesting a potential role of the 14-3-3beta/integrin beta1 interaction in the regulation of cell adhesion. Using tetracycline-regulated expression system, we showed that overexpression of 14-3-3beta stimulated cell spreading and migration on fibronectin but not on poly-L-lysine. However, the induced expression of 14-3-3beta did not affect tyrosine phosphorylation of FAK or its substrates, p130(cas) and paxillin, suggesting that 14-3-3beta regulated integrin-mediated cell spreading and migration by FAK-independent mechanisms. Taken together, these results identify an interaction between integrin and 14-3-3 proteins and suggest a potentially novel cellular function for 14-3-3 proteins in the regulation of integrin-mediated cell adhesion and signaling events.

Charge interactions in sperm-egg recognition

A novel method using derivatized agarose beads for investigating the types of molecules, when isolated from all others, that can form stable adhesive bonds, was recently described by Roque et al. (1996). The findings from this study were extended to living sea urchin cell systems. Both the bead results and the experiments with sea urchin cells suggested that phosphorylated amino acids can form stable adhesive bonds with positively charged peptides (Roque et al., 1996). As these experiments only examined phosphorylated amino acids, the validity of the hypotheses developed in the earlier study was dependent on extending the experiments to additional phosphorylated molecules. In this study, effects of D-mannose, D-mannose-1-phosphate, D-fructose, D-fructose-1-phosphate, maltose and maltose-1-phosphate on embryo cell reaggregation and sperm-egg interaction using untreated, jelly coat-free and vitelline layer disrupted Strongylocentrotus purpuratus sea urchin eggs were examined. The phosphorylated sugars (50 mM), and not their non-phosphorylated counterparts, strongly inhibited fertilization of the 3 types of eggs. ATP, at concentrations as low as 0.8 mM also completely inhibited fertilization. The phosphorylated sugars had little or no effect on reaggregating sea urchin blastula cells. A likely explanation of these results is that sperm-egg interaction in the sea urchin involves positively and negatively charged receptors; the positively charged receptors are blocked by exogenously added phosphorylated molecules. These and earlier studies indicate that by extending results from bead modeling studies to living systems, interesting information can be obtained regarding bonding mechanisms that may modulate adhesive interactions.

Effect of life in industrialized societies on hearing in natives of Easter Island

In an effort to determine whether life in industrialized societies can have an effect on hearing, 90 natives from Easter Island over 45 years old were evaluated. They underwent complete clinical and audiological assessment and were divided into groups according to those having lived only on the island or those having lived in modern civilization. With all factors being equal, except exposure to modern civilization, our results showed that living in civilized societies has a significant negative effect on hearing; the severity is directly proportional to the years of exposure. The median hearing thresholds of natives always living on the island (men and women combined) was found to be similar to those of female citizens of the United States; there was no significant difference in hearing thresholds between men and women among these natives. These results suggest that there are no significant inherent racial differences nor significant inherent differences between males and females in the sensitivity of hearing. A relationship between aging and hearing was noted and interpreted as true or intrinsic presbycusis. There were no cases of otosclerosis, Meniere's disease, or exostoses of the external ear canal among natives who had always lived on the island. Pure natives were found not to be prone to otitis media in spite of having an extremely high incidence of severe upper respiratory tract allergies.