Artériopathie des membres inférieurs : le traitement

International audienceMedical management of peripheral arterial disease (PAD) patients is aimed at limb symptom relief and reducing systemic major adverse events risk. For the first purpose: exercise therapy is recommended in case of claudication; multidisciplinary evaluation for surgical options is mandatory in case of critical limb ischaemia. Reducing cardiac and stroke risk can be achieved through: statin prescription in most of the cases; antiplatelet agents in symptomatic PAD patients; cardio-vascular risk factors control

Role of SLV in SLI substrate recognition by the Neurospora VS ribozyme

Substrate recognition by the VS ribozyme involves a magnesium-dependent loop/loop interaction between the SLI substrate and the SLV hairpin from the catalytic domain. Recent NMR studies of SLV demonstrated that magnesium ions stabilize a U-turn loop structure and trigger a conformational change for the extruded loop residue U700, suggesting a role for U700 in SLI recognition. Here, we kinetically characterized VS ribozyme mutants to evaluate the contribution of U700 and other SLV loop residues to SLI recognition. To help interpret the kinetic data, we structurally characterized the SLV mutants by NMR spectroscopy and generated a three-dimensional model of the SLI/SLV complex by homology modeling with MC-Sym. We demonstrated that the mutation of U700 by A, C, or G does not significantly affect ribozyme activity, whereas deletion of U700 dramatically impairs this activity. The U700 backbone is likely important for SLI recognition, but does not appear to be required for either the structural integrity of the SLV loop or for direct interactions with SLI. Thus, deletion of U700 may affect other aspects of SLI recognition, such as magnesium ion binding and SLV loop dynamics. As part of our NMR studies, we developed a convenient assay based on detection of unusual 31P and 15N N7 chemical shifts to probe the formation of U-turn structures in RNAs. Our model of the SLI/SLV complex, which is compatible with biochemical data, leads us to propose novel interactions at the loop I/loop V interface

Prevalence of sleep-disordered breathing in an African general population: The Benin Society and Sleep (BeSAS) study

International audienceBackground: Data on the prevalence of sleep-disordered breathing (SDB) in the African general population are scarce, and a better understanding is urgently needed. Our study aimed to objectively determine the prevalence of, and factors associated with, SDB in a large sample in Benin, west Africa.Methods: In the Benin Society and Sleep (BeSAS) cross-sectional study, participants aged 25 years and older were recruited from both urban and rural areas. Rural participants were recruited from Tanve, a village located 200 km north of Cotonou, and urban participants were recruited from Cotonou. The participants underwent respiratory polygraphy at home using a type-3 device that measures airflow through a nasal pressure sensor, respiratory effort (thoracic movement), and pulse oximetry. Clinical and morphometric data were also collected. SDB severity categories were defined according to the apnoea-hypopnoea index (AHI), with mild-to-severe SDB (AHI ≥5/h), moderate-to-severe SDB (AHI ≥15/h), and severe SDB (AHI ≥30/h).Findings: The study was completed from April 4, 2018 to Jan 15, 2021. Of 2909 participants recruited in the BeSAS study, 2168 (74·5%) underwent respiratory polygraphy. For the 1810 participants with complete polygraphic data (mean age 46 years, SD 15; 1163 [64·2%] women), the prevalence of mild-to-severe SDB (AHI ≥5/h) was 43·2% (95% CI 40·9-45·5), of moderate-to-severe SDB (AHI ≥15/h) was 11·6% (10·2-13·1), and of severe SDB (AHI ≥30/h) was 2·7% (2·0-3·5). Factors independently associated with SDB were advanced age, male sex, large neck circumference, abdominal obesity, overweight or obesity, and snoring. After multivariable adjustment, severe SDB was independently associated with hypertension in women (odds ratio 3·99, 95% CI 1·04-15·33; ptrend=0·044), but not in men (odds ratio 0·67, 0·22-2·05; Ptrend=0·63).Interpretation: The BeSAS study provides the first large-scale objective evaluation of SDB prevalence and associated factors in Africa. The high prevalence of SDB identified should stimulate the development of public health policies to prevent and treat this condition in African countries

AIRS: ARIEL IR spectrometer status

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Second asymptomatic carotid surgery trial (ACST-2) : a randomised comparison of carotid artery stenting versus carotid endarterectomy

Background: Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either carotid artery stenting (CAS) or carotid endarterectomy (CEA) can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death. Comparison of their long-term protective effects requires large-scale randomised evidence. Methods: ACST-2 is an international multicentre randomised trial of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. Patients were eligible if they had severe unilateral or bilateral carotid artery stenosis and both doctor and patient agreed that a carotid procedure should be undertaken, but they were substantially uncertain which one to choose. Patients were randomly allocated to CAS or CEA and followed up at 1 month and then annually, for a mean 5 years. Procedural events were those within 30 days of the intervention. Intention-to-treat analyses are provided. Analyses including procedural hazards use tabular methods. Analyses and meta-analyses of non-procedural strokes use Kaplan-Meier and log-rank methods. The trial is registered with the ISRCTN registry, ISRCTN21144362. Findings: Between Jan 15, 2008, and Dec 31, 2020, 3625 patients in 130 centres were randomly allocated, 1811 to CAS and 1814 to CEA, with good compliance, good medical therapy and a mean 5 years of follow-up. Overall, 1% had disabling stroke or death procedurally (15 allocated to CAS and 18 to CEA) and 2% had non-disabling procedural stroke (48 allocated to CAS and 29 to CEA). Kaplan-Meier estimates of 5-year non-procedural stroke were 2·5% in each group for fatal or disabling stroke, and 5·3% with CAS versus 4·5% with CEA for any stroke (rate ratio [RR] 1·16, 95% CI 0·86-1·57; p=0·33). Combining RRs for any non-procedural stroke in all CAS versus CEA trials, the RR was similar in symptomatic and asymptomatic patients (overall RR 1·11, 95% CI 0·91-1·32; p=0·21). Interpretation: Serious complications are similarly uncommon after competent CAS and CEA, and the long-term effects of these two carotid artery procedures on fatal or disabling stroke are comparable