The ICC Compression Questionnaire: A Comprehensive Tool to Evaluate Compression Materials or Devices Applied in Subjects with Lymphedema or Chronic Venous Disease

Background: Compression therapy is an important part of the treatment of patients with lymphedema or chronic venous disease. However, there is no validated questionnaire evaluating the effect of compression and its acceptance by the patient. Therefore, the aims of this study were to construct a questionnaire evaluating the effect of compression and its acceptance by the patient, that is, the Dutch ICC Compression Questionnaire (ICC-CQ), to investigate its reliability and validity, and to translate it into English. Methods and Results: Eleven experts in applying compression and 51 Dutch patients with experience of using compression were involved in the construction process. One part of the ICC-CQ has to be completed by the patient and evaluates seven domains. The other part has to be completed by the health care provider and comprises three domains. Reliability and validity of the final version was investigated in a new group of 79 Dutch-speaking patients with lymphedema or chronic venous disease, wearing compression garments (N = 52) or bandages (N = 27). Except for one domain, the Intraclass Correlation Coefficients for test-rest/interrater reliability ranged from 0.55 to 0.93. Cronbach's alpha for internal consistency ranged from 0.71 to 0.97. Eighty-nine percent of the patients fully understood the questionnaire indicating good face validity, and 87% found it complete indicating good content validity. Construct validity was considered good since 10 out of 11 hypotheses were accepted. Conclusion: The ICC-CQ is the first reliable and valid questionnaire evaluating different kinds of compression and the experience by patients with lymphedema or chronic venous disease

Paediatric lymphoedema : An audit of patients seen by the paediatric and primary lymphoedema group of vascular European Reference Network (VASCERN)

Little is known about the overall prevalence of lymphoedema in children and the types of paediatric lymphoedema seen by specialist centres. Therefore, this study was aimed to provide a profile of children with primary or secondary lymphoedema seen by the expert centres of the paediatric and primary lymphoedema working group (PPL-WG) of VASCERN and to compare the profile between the different countries.A retrospective review of all children (aged up to 18 years) seen for the first time by the expert centres over one year (2019) was carried out. Lymphoedema-, patient- and genetics-related data was collected and described for the whole group and compared between the different European countries/UK.In 2019, a total of 181 new children were seen by eight expert centres. For primary lymphoedema, the phenotype was based on the St George's classification of lymphatic anomalies. The percentages diagnosed according to each category were: 7.2% for syndromic lymphoedema, 2.8% for systemic/visceral involvement, 30.4% for congenital, 35.9% for late-onset lymphoedema and 19.3% for vascular/lymphatic malformations. 4.4% had secondary lymphoedema. Nearly 10% of all children had had at least one episode of cellulitis. The median delay from onset of symptoms to being seen by an expert centre was 2.4 years. In 44.4% of the children with primary lymphoedema a genetic test was performed, of which 35.8% resulted in a molecular diagnosis. Across the different centres, there was a wide variety in distribution of the different categories of paediatric lymphoedema diagnosed and the frequency of genetic testing.In conclusion, this paper has demonstrated that there is a large delay between the onset of paediatric lymphoedema and the first visit in the expert centres and that an episode of cellulitis is a relatively common complication. Diagnostic variation across the centres may reflect different referral criteria. Access to genetic testing was limited in some centres. It is recommended that these issues are addressed in the future work of the PPL-WG to improve the referral to the expert centres and the consistency in service provision for paediatric lymphoedema in Europe.Peer reviewe

Exercise is associated with younger methylome and transcriptome profiles in human skeletal muscle

Exercise training prevents age-related decline in muscle function. Targeting epigenetic aging is a promising actionable mechanism and late-life exercise mitigates epigenetic aging in rodent muscle. Whether exercise training can decelerate, or reverse epigenetic aging in humans is unknown. Here, we performed a powerful meta-analysis of the methylome and transcriptome of an unprecedented number of human skeletal muscle samples (n = 3176). We show that: (1) individuals with higher baseline aerobic fitness have younger epigenetic and transcriptomic profiles, (2) exercise training leads to significant shifts of epigenetic and transcriptomic patterns toward a younger profile, and (3) muscle disuse "ages" the transcriptome. Higher fitness levels were associated with attenuated differential methylation and transcription during aging. Furthermore, both epigenetic and transcriptomic profiles shifted toward a younger state after exercise training interventions, while the transcriptome shifted toward an older state after forced muscle disuse. We demonstrate that exercise training targets many of the age-related transcripts and DNA methylation loci to maintain younger methylome and transcriptome profiles, specifically in genes related to muscle structure, metabolism, and mitochondrial function. Our comprehensive analysis will inform future studies aiming to identify the best combination of therapeutics and exercise regimes to optimize longevity

Meta-analysis of genome-wide DNA methylation and integrative omics of age in human skeletal muscle

International audienceBackground: Knowledge of age-related DNA methylation changes in skeletal muscle is limited, yet this tissue is severely affected by ageing in humans.Methods: We conducted a large-scale epigenome-wide association study meta-analysis of age in human skeletal muscle from 10 studies (total n = 908 muscle methylomes from men and women aged 18-89 years old). We explored the genomic context of age-related DNA methylation changes in chromatin states, CpG islands, and transcription factor binding sites and performed gene set enrichment analysis. We then integrated the DNA methylation data with known transcriptomic and proteomic age-related changes in skeletal muscle. Finally, we updated our recently developed muscle epigenetic clock (https://bioconductor.org/packages/release/bioc/html/MEAT.html).Results: We identified 6710 differentially methylated regions at a stringent false discovery rate <0.005, spanning 6367 unique genes, many of which related to skeletal muscle structure and development. We found a strong increase in DNA methylation at Polycomb target genes and bivalent chromatin domains and a concomitant decrease in DNA methylation at enhancers. Most differentially methylated genes were not altered at the mRNA or protein level, but they were nonetheless strongly enriched for genes showing age-related differential mRNA and protein expression. After adding a substantial number of samples from five datasets (+371), the updated version of the muscle clock (MEAT 2.0, total n = 1053 samples) performed similarly to the original version of the muscle clock (median of 4.4 vs. 4.6 years in age prediction error), suggesting that the original version of the muscle clock was very accurate.Conclusions: We provide here the most comprehensive picture of DNA methylation ageing in human skeletal muscle and reveal widespread alterations of genes involved in skeletal muscle structure, development, and differentiation. We have made our results available as an open-access, user-friendly, web-based tool called MetaMeth (https://sarah-voisin.shinyapps.io/MetaMeth/)

Genetic mechanisms of critical illness in COVID-19.

Host-mediated lung inflammation is present1, and drives mortality2, in the critical illness caused by coronavirus disease 2019 (COVID-19). Host genetic variants associated with critical illness may identify mechanistic targets for therapeutic development3. Here we report the results of the GenOMICC (Genetics Of Mortality In Critical Care) genome-wide association study in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units. We have identified and replicated the following new genome-wide significant associations: on chromosome 12q24.13 (rs10735079, P = 1.65 × 10-8) in a gene cluster that encodes antiviral restriction enzyme activators (OAS1, OAS2 and OAS3); on chromosome 19p13.2 (rs74956615, P = 2.3 × 10-8) near the gene that encodes tyrosine kinase 2 (TYK2); on chromosome 19p13.3 (rs2109069, P = 3.98 ×  10-12) within the gene that encodes dipeptidyl peptidase 9 (DPP9); and on chromosome 21q22.1 (rs2236757, P = 4.99 × 10-8) in the interferon receptor gene IFNAR2. We identified potential targets for repurposing of licensed medications: using Mendelian randomization, we found evidence that low expression of IFNAR2, or high expression of TYK2, are associated with life-threatening disease; and transcriptome-wide association in lung tissue revealed that high expression of the monocyte-macrophage chemotactic receptor CCR2 is associated with severe COVID-19. Our results identify robust genetic signals relating to key host antiviral defence mechanisms and mediators of inflammatory organ damage in COVID-19. Both mechanisms may be amenable to targeted treatment with existing drugs. However, large-scale randomized clinical trials will be essential before any change to clinical practice

Added value of imaging of lymphatic system through near-infrared fluorescence imaging in the treatment of lymphoedema

status: publishe

The discovery of the lymphatic system in the seventeenth century. Part VI: the microscopic discovery of the subtle anatomy

The discovery of chyle and lymph vessels had furthered the dream of understanding the body's structure and functions. Initially it was thought that chyle was sucked from the intestines through the open mouths of chyle vessels, and that lymph vessels were side branches of arterial end branches. In the second half of the 17th century, microscopy became an adjuvant for research into the subtle anatomy of the lymphatic system. In the present paper, we will focus on its initial use for the study of the structure and function of chyle and lymph vessels, and lymph glands.status: publishe

The discovery of the lymphatic system in the seventeenth century. Part V: an ode to the nerves

The English anatomists Francis Glisson and Thomas Wharton introduced theories on the use of recently discovered lymphatic system in the1650s. Their main idea was that membranous tissues were supplied by nerves with a vital fluid produced within nutritive glands, to be carried to the brain and thence from the brain to all membranous tissues, including glands. They stated that the distribution of the vital fluid was based on the similarity between its ingredients and the needs of the recipient tissues, and not on the weight, size or location of pores encountered, as maintained by Descartes. Lymph, a mixture of waste from the consumed vital fluid and moisture transuded by arterial capillaries, was absorbed by the lymphatic vessels to be excreted via excretory glands, or to be diverted to the venous system by reductive glands. The theories of Glisson and Wharton were very soon rejected to be replaced by a mechanistic philosophy, a legacy of Descartes' theories.status: publishe

The discovery of lymphatic system in the seventeenth century. Part I: the early history

The early history of lymphatic anatomy from Hippocrates (ca. 460-377 B.C.) to Eustachius (1510-1574). The presence of lymphatic vessels and lymph nodes was reported by ancient anatomists without any accurate knowledge of their true functions. Lymph nodes were described as spongy structures, spread over the whole body for the support of vulnerable body parts. Digestion was explained as being the resorption of clear chyle from digested food by the open endings of chyle vessels. The first insights into the place of lymphatic components within nutrition emanated from the medical school of Alexandria (fourth century B.C.) where vivisection was a common practice. Herophilus and Erasistratus described mesenteric veins full of clear liquid, air or milk. For Galen of Pergamum, (104-210) mesenteric lymph nodes also had a nutritional function. He described three different types of mesenteric vessels, namely, the arterial vessels, for the transport of spirituous blood to the intestines; the venous side branches of the portal vein, for the transport of nutritive blood from the liver to the intestines; and small vessels, from the intestines to the mesenteric lymph nodes (serous lymph vessels?). According to Galen, chyle was transported via the above-mentioned mesenteric venous vessels from the intestines to the portal vein and liver, where it was transformed into nutritive blood. This doctrine would be obliterated in the seventeenth century by the discovery of systemic circulation and of the drainage of chyle through a thoracic duct to the subclavian veins.peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tacb20status: publishe

The discovery of the lymphatics in the seventeenth century. Part iii: the dethroning of the liver

Around 1650, the thoracic chyle duct and the serous lymph vessels were discovered nearly simultaneously in four different places on the European continent. The new theory was that all ingested fluid, digested food, and serous lymph liquid were drained towards the subclavian veins, and then to the heart where they was mixed with and transformed into blood, which had been the supposed function of the liver. None of the discoverers proposed a valuable alternative function for the liver. Bile formation and filtration of serum from the blood to carry it through lymph vessels to the chyle sac (cysterna chyli) were the only remaining possible liver functions. The liver was dethroned from its presumed function as blood-forming organ with an epitaph starting with the words 'Stay, Wayfarer, Enclosed in this tomb is he who entombed very many'.peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tacb20status: publishe