KI and TEDA influences towards the retention of radiotoxic CH3I by activated carbons

Activated carbons (AC) are widely used within the ventilation networks of nuclear facilities to trap volatile iodine species. In this paper, the performances of various commercial activated carbons towards the trapping of γ-labelled methyl iodide were evaluated in semi-pilot scale under different R.H. according to normalized procedures. A combination between the retention performances and the physico-chemical properties as deduced from several techniques was performed to gain insights about the AC influencing parameters on γ-CH₃I capture. Different trends were obtained depending on the impregnant nature and the studied conditions. A high sensitivity of KI/AC towards water vapor was outlined. At R.H. = 40%. The enhancement of water uptake by KI/AC as deduced from water adsorption experiments, leads to decrease the available microporosity for CH₃I physisorption, inducing therefore the reduction of performances as a function of KI content at these conditions. At R.H. = 90%, the adsorption mechanism was found to be governed by isotopic exchange reaction since 90% of the microporosity was occupied by water molecules. Therefore, a slight increase of DF was obtained in these conditions. This sensitivity was found to be of a lesser extent for TEDA/AC displaying the highest retention performances whatever the studied condition.

No difference in HIV-1 integrase inhibitor resistance between CSF and blood compartments

BACKGROUND

Little is known about HIV-1 integrase inhibitor resistance in the CNS.

OBJECTIVES

This study aimed to evaluate integrase inhibitor resistance in CSF, as a marker of the CNS, and compare it with the resistance in plasma.

METHODS

HIV integrase was sequenced both in plasma and CSF for 59 HIV-1 patients. The clinical and biological data were collected from clinical routine care.

RESULTS

Among the 59 HIV-1 patients, 32 (54.2%) were under antiretroviral (ARV) treatment. The median (IQR) HIV-1 RNA in the plasma of viraemic patients was 5.32 (3.85-5.80) and 3.59 (2.16-4.50) log10 copies/mL versus 4.79 (3.56-5.25) and 3.80 (2.68-4.33) log10 copies/mL in the CSF of ARV-naive and ARV-treated patients, respectively. The patients were mainly infected with non-B subtypes (72.2%) with the most prevalent recombinant form being CRF02_AG (42.4%). The HIV-1 integrase sequences from CSF presented resistance mutations for 9/27 (33.3%) and 8/32 (25.0%) for ARV-naive (L74I, n = 3; L74I/M, n = 1; T97A, n = 1; E157Q, n = 4) and ARV-treated (L74I, n = 6; L74M, n = 1; T97A, n = 1; N155H, n = 1) patients, respectively. Integrase inhibitor resistance mutations in CSF were similar to those in plasma, except for 1/59 patients.

CONCLUSIONS

This work shows similar integrase inhibitor resistance profiles in the CNS and plasma in a population of HIV-1 viraemic patients.

Differential association between inflammatory cytokines and multiorgan dysfunction in COVID-19 patients with obesity

To investigate the mechanisms underlying the SARS-CoV-2 infection severity observed in patients with obesity, we performed a prospective study of 51 patients evaluating the impact of multiple immune parameters during 2 weeks after admission, on vital organs' functions according to body mass index (BMI) categories. High-dimensional flow cytometric characterization of immune cell subsets was performed at admission, 30 systemic cytokines/chemokines levels were sequentially measured, thirteen endothelial markers were determined at admission and at the zenith of the cytokines. Computed tomography scans on admission were quantified for lung damage and hepatic steatosis (n = 23). Abnormal BMI (> 25) observed in 72.6% of patients, was associated with a higher rate of intensive care unit hospitalization (p = 0.044). SARS-CoV-2 RNAaemia, peripheral immune cell subsets and cytokines/chemokines were similar among BMI groups. A significant association between inflammatory cytokines and liver, renal, and endothelial dysfunctions was observed only in patients with obesity (BMI > 30). In contrast, early signs of lung damage (ground-glass opacity) correlated with Th1/M1/inflammatory cytokines only in normal weight patients. Later lesions of pulmonary consolidation correlated with BMI but were independent of cytokine levels. Our study reveals distinct physiopathological mechanisms associated with SARS-CoV-2 infection in patients with obesity that may have important clinical implications.

Effects of water vapour and temperature on the retention of radiotoxic CH3I by silver faujasite zeolites

In this work, Ag/X and Ag/Y faujasite zeolites were evaluated as candidate sorbents for the retention of methyl iodide under conditions close to those expected in a severe nuclear accident. Different categories of tests were conducted from laboratory to semi-pilot scales. First, the effects of temperature and water vapour on the CH₃I retention/decomposition mechanism were investigated under lab-scale conditions. More specifically, the CH₃I adsorption capacities and the fate of its main decomposition products (oxygenated compounds and alkanes) were measured under dynamic conditions at different temperatures (35, 100 and 250 °C). Then, the decontamination factors of Ag/X and Ag/Y silver faujasites exchanged with different silver contents were monitored according to the time on stream using a very low CH₃I concentration (1 ppmv). Finally, a parametric study was conducted at semi-pilot scale using realistic [CH₃I]/[H₂O] molar ratio ≈ 10^-6 and temperatures in the range 20-90 °C. Those experiments were helpful in order to assess the effects of some important parameters relevant to the adsorbents or operating conditions.

Eryptosis and circulating blood cells microparticules in sickle cell diseases

Sickle cell disease(SCD)is a monogenic disease, in which the severity and symptoms vary widely.The sickle cell mutation is the origin of all functional and structural alterations of red blood cell(RBC)which induces the acceleration of eryptosis and formation of Circulating blood cells microparticules(MPs)which has the consequence of acute anemia and increasing the thrombotic risks in sickle cell patients. Eryptosis is the suicidal erythrocyte death characterized by erythrocyte membrane scrambling by phosphatidylserine(PS)externalization. MPs are an extracellular vesicules released following cellular activation, stress or apoptosis. These parameters are able to modulate many biological functions, and considered as biomarkers of preventive diagnostic of SCD. This present study aims to determine the cellular biomarkers to implementation new and innovative methods of the preventive diagnosis of SCDacute complications. We propose to study the mechanisms involved in the triggering of eryptosis and to quantify microparticles derived from platelets and erythrocytes of homozygous sickle cell patients.

Following clinical diagnosis, homozygous SCDpatients and healthy donors were sampled for hematological and cellular assays. The exploration of eryptosis and MPs was performed by a flow cytometry by determining the viability parameters of red blood cells.

The outcome of our study indicated that Eryptosis in sickle cell patients is triggered essentially by high Ca2 + entry and narrowing of red blood cells. However, the pathway of ceramides and ERO can also considered a stimulating factor of eryptosis. Eryptosis ensures healthy erythrocyte quantity in circulation whereas excessive eryptosis is the cause of acute anemia and may contribute to vaso-occlusive crisis in SCD patients.For MPs study,microparticles derived from platelets and erythrocytes clearly increased in SCD patients. This suggests that erythrocytes MPs may contribute to thrombotic risk andchronic hemolytic anemia.

Key messages

Potentiel biomarkers in the preventive diagnosis of sickle cell disease. Eryptosis and plasmatic microparticules as potentiel biomarkers.

On Line Measurement of Organic Iodine During a Severe Nuclear Accident

A severe nuclear accident may induce a dramatic dissemination of radioactive species into the environment. In that respect, improving the nuclear safety remains an important challenge to improve the society acceptability towards this energy. A solution may consist on implementing robust and reliable measurement systems operating near the Containment Venting Systems (CVS). These devices should be able to provide real time monitoring of the emitted fission products (FPs) in the course of a hypothetical accidental sequence. In the present study, a peculiar attention was devoted to iodine species (namely CH3I) measurement by complementary techniques (photoacoustic spectroscopy and gas chromatography). The most important results will be described here.