Diabetic foot ulcers segmentation challenge report: Benchmark and analysis

Monitoring the healing progress of diabetic foot ulcers is a challenging process. Accurate segmentation of foot ulcers can help podiatrists to quantitatively measure the size of wound regions to assist prediction of healing status. The main challenge in this field is the lack of publicly available manual delineation, which can be time consuming and laborious. Recently, methods based on deep learning have shown excellent results in automatic segmentation of medical images, however, they require large-scale datasets for training, and there is limited consensus on which methods perform the best. The 2022 Diabetic Foot Ulcers segmentation challenge was held in conjunction with the 2022 International Conference on Medical Image Computing and Computer Assisted Intervention, which sought to address these issues and stimulate progress in this research domain. A training set of 2000 images exhibiting diabetic foot ulcers was released with corresponding segmentation ground truth masks. Of the 72 (approved) requests from 47 countries, 26 teams used this data to develop fully automated systems to predict the true segmentation masks on a test set of 2000 images, with the corresponding ground truth segmentation masks kept private. Predictions from participating teams were scored and ranked according to their average Dice similarity coefficient of the ground truth masks and prediction masks. The winning team achieved a Dice of 0.7287 for diabetic foot ulcer segmentation. This challenge has now entered a live leaderboard stage where it serves as a challenging benchmark for diabetic foot ulcer segmentation.

Associations between Chewing Difficulty, Subjective Cognitive Decline, and Related Functional Difficulties among Older People without Dementia: Focus on Body Mass Index

OBJECTIVE

This study aimed to determine whether chewing difficulty is associated with subjective cognitive decline (SCD) and related functional difficulties by body mass index.

DESIGN

A population-based cross-sectional study.

SETTING AND PARTICIPANTS

A nationwide sample of 54,004 individuals aged ≥65 years from the 2018 Korea Community Health Survey.

MEASUREMENTS

SCD and SCD-related functional difficulties were measured using the cognitive decline module of the Behavioral Risk Factor Surveillance System. Chewing difficulty was assessed based on a self-report questionnaire from an oral health-related behaviors interview survey. BMI was calculated from objective values by measuring height and weight through a physical meter.

RESULTS

Among the 54,004 individuals, the prevalence of SCD in underweight, overweight, and obesity group was 33.6% (n = 806), 30.3% (n = 9,691), and 28.7% (n=5,632) respectively. Chewing difficulty was associated with SCD and SCD-related functional difficulties. This association was more pronounced in underweight (BMI: <18.5 kg/m2) people [underweight: (odds ratio [OR] = 1.68, 95% confidence interval [CI] 1.48-1.92); normal weight: OR = 1.13, 95% CI 1.04-1.22; obese: OR = 1.15, 95% CI 1.05-1.27]. Similar trends were demonstrated for SCD-related functional difficulties (underweight: OR = 1.53, 95% CI 1.17-2.01; normal weight: OR = 1.36, 95% CI 1.15-1.63; obese: OR = 1.50, 95% CI 1.22-1.86).

CONCLUSIONS

Chewing difficulty was associated with SCD and SCD-related functional difficulties in older people. Our results suggest that underweight status may play roles in the associations between chewing difficulty and SCD and SCD-related functional difficulties.

Temporary work and depressive symptoms in South Korean workers

Background

In many countries, including South Korea, labour market changes have led to an increase in unstable, temporary jobs. There is evidence that workers in such jobs may experience poorer mental health than those in more stable employment.

Aims

To investigate the association between temporary employment and depressive symptoms in South Korean workers.

Methods

We analysed data from the 2010-2014 Korean Welfare Panel Study (KOWEPS). Employment type was categorized into workers paid per day of labour (day labourers), those on short-term contracts (fixed-term workers) and permanent workers. The association between employment type and depressive symptoms, measured using the Center for Epidemiological Studies Depression scale (CES-D 11), was examined using the generalized estimating equation model.

Results

A total of 3756 workers aged 20-59 were included in the 2010 baseline population. Day labourers had the highest mean CES-D 11 score, followed by fixed-term workers and permanent workers. With the day labourer group as reference, fixed-term workers (β: -1.5027, P < 0.001) and permanent workers (β: -2.1848, P < 0.001) showed statistically significant decreases in depression scores.

Conclusions

Compared with day labourers, fixed-term workers and permanent workers had progressively lower depression scores. The findings of this study suggest that mental health inequalities based on employment type exist in South Korea.

Telomere dysfunction alters the chemotherapeutic profile of transformed cells

Telomerase inhibition has been touted as a novel cancer-selective therapeutic goal based on the observation of high telomerase levels in most cancers and the importance of telomere maintenance in long-term cellular growth and survival. Here, the impact of telomere dysfunction on chemotherapeutic responses was assessed in normal and neoplastic cells derived from telomerase RNA null (mTERC(-/-)) mice. Telomere dysfunction, rather than telomerase per se, was found to be the principal determinant governing chemosensitivity specifically to agents that induced double-stranded DNA breaks (DSB). Enhanced chemosensitivity in telomere dysfunctional cells was linked to therapy-induced fragmentation and multichromosomal fusions, whereas telomerase reconstitution restored genomic integrity and chemoresistance. Loss of p53 function muted the cytotoxic effects of DSB-inducing agents in cells with telomere dysfunction. Together, these results point to the combined use of DSB-inducing agents and telomere maintenance inhibition as an effective anticancer therapeutic approach particularly in cells with intact p53-dependent checkpoint responses.

Isolation and characterization of beta-galactoside specific lectin from Korean mistletoe (Viscum album var. coloratum) with lactose-BSA-sepharose 4B and changes of lectin conformation

Lectins and its A- and B-chains from Korean mistletoe (Viscum album var. coloratum) were isolated by affinity chromatography on the Sepharose 4B modified by lactose-BSA conjugate synthesized by reductive amination of ligand (lactose) to epsilon-amino groups of lysine residues of spacer (BSA) after reduction by NaCNBH3. The lactose-BSA conjugate was coupled to Sepharose 4B activated by cyanogen bromide. The molecular weight determined by SDS-PAGE were a 31 kD of A-chain and a 35 kD of B-chain. Amino acid analysis and N-terminal sequencing were performed. The effects of pH, temperature and guanidine chloride on the conformation of the lectin were investigated by measuring its intrinsic fluorescence and compared with its hemagglutinating activities. Blue shift was detected on the acidic pH and there was a close relationship between activities and conformation of the lectin. Under denaturing conditions, the tryptophan emission profile of lectin showed typical denaturational red shift which also correspond to the conformations and activity of lectin.