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1.
Anal Chem ; 96(19): 7558-7565, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38696396

ABSTRACT

With a view to potentiometric sensing with minimal calibration requirements and high long-term stability, colloid-imprinted mesoporous (CIM) carbon was functionalized by the covalent attachment of a cobalt redox buffer and used as a new solid contact for ion-selective electrodes (ISEs). The CIM carbon surface was first modified by electroless grafting of a terpyridine ligand (Tpy-ph) using diazonium chemistry, followed by stepwise binding of Co(II) and an additional Tpy ligand to the grafted ligand, forming a bis(terpyridine) Co(II) complex, CIM-ph-Tpy-Co(II)-Tpy. Half a molar equivalent of ferrocenium tetrakis(3-chlorophenyl)borate was then used to partially oxidize the Co(II) complex. Electrodes prepared with this surface-attached CIM-ph-Tpy-Co(III/II)-Tpy redox buffer as a solid contact were tested as K+ sensors in combination with valinomycin as the ionophore and Dow 3140 silicone or plasticized poly(vinyl chloride) (PVC) as the matrixes for the ion-selective membrane (ISM). This solid contact is characterized by a redox capacitance of 3.26 F/g, ensuring a well-defined interfacial potential that underpins the transduction mechanism. By use of a redox couple as an internal reference element to control the phase boundary potential at the interface of the ISM and the CIM carbon solid contact, solid-contact ion-selective electrodes (SC-ISEs) with a standard deviation of E° as low as 0.3 mV for plasticized PVC ISMs and 3.5 mV for Dow 3140 silicone ISMs were obtained. Over 100 h, these SC-ISEs exhibit an emf drift of 20 µV/h for plasticized PVC ISMs and 62 µV/h for silicone ISMs. The differences in long-term stability and reproducibility between electrodes with ISMs comprising either a plasticized PVC or silicone matrix offer valuable insights into the effect of the polymeric matrix on sensor performance.

2.
EuroIntervention ; 20(5): e281-e288, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38436368

ABSTRACT

BACKGROUND: Data comparing transcatheter mitral valve implantation (TMVI) with surgical mitral valve replacement (SMVR) are lacking. AIMS: This study sought to compare the 30-day Valve Academic Research Consortium (VARC)-3 device success of TMVI with that of SMVR. METHODS: Matching protocol combined exact matching (sex, atrial fibrillation, previous surgical aortic valve replacement [SAVR] or coronary artery bypass grafting [CABG]), coarsened exact matching (age) and propensity score matching (body mass index, mitral valve pathology and concomitant tricuspid regurgitation). RESULTS: A total of 40 Tendyne TMVI and 80 SMVR patients with similar baseline characteristics were analysed (TMVI vs SMVR): age (78 years [interquartile range [{IQR} 75; 80] vs 78 years [IQR 73; 80]; p=0.8), female (60% vs 60%; p=1.0), atrial fibrillation (67.5% vs 63.7%; p=0.8), previous SAVR (12.5% vs 10.0%; p=0.8), previous CABG (20.0% vs 16.2%; p=0.8), body mass index (25.54 kg/m² vs 25.24 kg/m²; p=0.7) and valve pathology (mitral regurgitation: 70.0% vs 73.8%, mitral stenosis: 7.5% vs 3.8%, and mixed disease: 22.5% vs 22.5%; p=0.6). Most baseline characteristics not included in the matching model were balanced among the TMVI/SMVR cohorts: European System for Cardiac Operative Risk Evaluation (EuroSCORE) II (5.8% [IQR 2.9; 7.5] vs 4.2% [IQR 2.4; 6.8]; p=0.3) and Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score (5.2% [IQR 3.2; 8.6] vs 4.1% [IQR 3.3; 6.1]; p=0.076). Coronary artery disease (67.5% vs 32.5%; p<0.001) and previous percutaneous coronary intervention (47.5% vs 25.0%; p=0.023) differed among groups. Mitral VARC (MVARC) device success at 30 days was achieved in 82.5% of patients after TMVI and 57.5% of patients after SMVR (p=0.04). MVARC procedural success at 30 days was 75.0% after TMVI versus 52.5% after SMVR (p=0.07). Thirty-day mortality (2.5% vs 3.8%; p=0.47), technical success (97.5% vs 97.5%; p=1.0), major bleeding (17.5% vs 18.7%; p=0.087), stroke (5.0% vs 4.9%; p=1.0) and postoperative haemodialysis (7.5% vs 5.2%; p=0.4) were similar in both groups. CONCLUSIONS: Patients with intermediate surgical risk, according to STS-PROM and EuroSCORE II, demonstrated higher rates of MVARC device at 30 days after TMVI compared to 30 days after SMVR. Rates of survival and procedural success, neurological, renal and bleeding complications were similar. Transfusion count and length of stay were lower after TMVI. For elderly patients at intermediate risk, a TMVI eligibility assessment may be considered.


Subject(s)
Atrial Fibrillation , Mitral Valve Insufficiency , Mitral Valve Stenosis , Surgeons , Aged , Humans , Female , Mitral Valve/surgery , Atrial Fibrillation/surgery , Mitral Valve Insufficiency/surgery
3.
Langmuir ; 40(3): 1785-1792, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38198594

ABSTRACT

The use of large surface area carbon materials as transducers in solid-contact ion-selective electrodes (ISEs) has become widespread. Desirable qualities of ISEs, such as a small long-term drift, have been associated with a high capacitance that arises from the formation of an electrical double layer at the interface of the large surface area carbon material and the ion-selective membrane. The capacitive properties of these ISEs have been observed using a variety of techniques, but the effects of the ions present in the ion-selective membrane on the measured value of the capacitance have not been studied in detail. Here, it is shown that changes in the size and concentration of the ions in the ion-selective membrane as well as the polarity of the polymeric matrix result in capacitances that can vary by up to several hundred percent. These data illustrate that the interpretation of comparatively small differences in capacitance for different types of solid contacts is not meaningful unless the composition of the ion-selective membrane is taken into account.

4.
Clin Chem Lab Med ; 62(3): 551-561, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-37870269

ABSTRACT

OBJECTIVES: Children with congenital heart disease (CHD) undergoing cardiac surgery on cardiopulmonary bypass (CPB) are at risk for systemic inflammation leading to endothelial dysfunction associated with increased morbidity. Bioactive adrenomedullin (bio-ADM) is a peptide regulating vascular tone and endothelial permeability. The aim of this study was to evaluate the dynamics of plasma bio-ADM in this patient cohort and its role in capillary leak. METHODS: Plasma samples from 73 pediatric CHD patients were collected for bio-ADM measurement at five different timepoints (TP) in the pre-, intra-, and post-operative period. The primary endpoint was a net increase in bio-ADM levels after surgery on CPB. Secondary endpoints included association of bio-ADM levels with clinical signs for endothelial dysfunction. RESULTS: Bio-ADM levels increased after surgery on CPB from pre-operative median of 12 pg/mL (IQR [interquartile range] 12.0-14.8 pg/mL) to a maximum post-operative median of 48.8 pg/mL (IQR 34.5-69.6 pg/mL, p<0.001). Bio-ADM concentrations correlated positively with post-operative volume balance, (r=0.341; p=0.005), increased demand for vasoactive medication (duration: r=0.415; p<0.001; quantity: TP3: r=0.415, p<0.001; TP4: r=0.414, p<0.001), and hydrocortisone treatment for vasoplegia (bio-ADM median [IQR]:129.1 [55.4-139.2] pg/mL vs. 37.9 [25.2-64.6] pg/mL; p=0.034). Patients who required pleural effusion drainage revealed higher bio-ADM levels compared to those who did not (median [IQR]: 66.4 [55.4-90.9] pg/mL vs. 40.2 [28.2-57.0] pg/mL; p<0.001). CONCLUSIONS: Bio-ADM is elevated in children after cardiac surgery and higher levels correlate with clinical signs of capillary leakage. The peptide should be considered as biomarker for endothelial dysfunction and as potential therapeutic target in this indication.


Subject(s)
Cardiac Surgical Procedures , Heart Defects, Congenital , Infant , Humans , Child , Adrenomedullin , Cardiopulmonary Bypass , Biomarkers , Heart Defects, Congenital/surgery
5.
Adv Mater ; 36(8): e2309778, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38105339

ABSTRACT

The ability to miniaturize ion-selective sensors that enable microsensor arrays and wearable sensor patches for ion detection in environmental or biological samples requires all-solid-state sensors with solid contacts for transduction of an ion activity into an electrical signal. Nanostructured carbon materials function as effective solid contacts for this purpose. They can also contribute to improved potential signal stability, reducing the need for frequent sensor calibration. In this Perspective, the structural features of various carbon-based solid contacts described in the literature and their respective abilities to reduce potential drift during long-term, continuous measurements are compared. These carbon materials include nanoporous carbons with various architectures, carbon nanotubes, carbon black, graphene, and graphite-based solid contacts. The effects of accessibility of ionophores, ionic sites, and other components of an ion-selective membrane to the internal or external carbon surfaces are discussed, because this impacts double-layer capacitance and potential drift. The effects of carbon composition on water-layer formation are also considered, which is another contributor to potential drift during long-term measurements. Recommendations regarding the selection of solid contacts and considerations for their characterization and testing in solid-contact ion-selective electrodes are provided.

6.
Biotechnol Prog ; 39(6): e3375, 2023.
Article in English | MEDLINE | ID: mdl-37531318

ABSTRACT

Increasing plasmid demand for both production of viral and gene therapies as well as nucleic acid based vaccines has highlighted bottlenecks in production. One bottleneck is traditional bead-based chromatography as a capture step. To meet the needs of fast-growing markets, new production solutions are needed. These solutions must enable efficient capture of a diverse range of plasmid types and excellent clearance of bacterial host impurities, such as endotoxin. Enhanced endotoxin clearance during chromatographic purification has previously been demonstrated with detergents such as Triton™ X-100. However, degradation products of Triton™ X-100 are known to have a negative environmental impact, and more sustainable, environmentally benign alternatives have been identified. This work establishes an efficient, intensified plasmid capture using convective anion exchange (AEX) chromatography. The feasibility of the intensified capture approach was assessed with different membrane and a monolith AEX supports. Various detergents from different physico-chemical classes were evaluated with different AEX technologies. Purification efficiency evaluated endotoxin and host cell protein (HCP) clearance, plasmid yield, potential interference of the detergents with analytical in-process control assays, and overall process compatibility. This comprehensive screening approach provides valuable insights to intensified plasmid production.


Subject(s)
Detergents , Endotoxins , Endotoxins/genetics , Chromatography, Ion Exchange/methods , Plasmids/genetics , Anions
7.
Anal Chem ; 95(33): 12419-12426, 2023 08 22.
Article in English | MEDLINE | ID: mdl-37552138

ABSTRACT

Solid-contact ion-selective electrodes (SC-ISEs) in direct long-term contact with physiological samples must be biocompatible and resistant to biofouling, but most wearable SC-ISEs proposed to date contain plasticized poly(vinyl chloride) (PVC) membranes, which have poor biocompatibility. Silicones are a promising alternative to plasticized PVC because of their excellent biocompatibility, but little work has been done to study the relationship between silicone composition and ISE performance. To address this, we prepared and tested K+ SC-ISEs with colloid-imprinted mesoporous (CIM) carbon as the solid contact and three different condensation-cured silicones: a custom silicone prepared in-house (Silicone 1), a commercial silicone (Dow 3140, Silicone 2), and a commercial fluorosilicone (Dow 730, Fluorosilicone 1). SC-ISEs prepared with each of these polymers and the ionophore valinomycin and added ionic sites exhibited Nernstian responses, excellent selectivities, and signal drifts as low as 3 µV/h in 1 mM KCl solution. All ISEs maintained Nernstian response slopes and had only very slightly worsened selectivities after 41 h exposure to porcine plasma (log KK,Na values of -4.56, -4.58, and -4.49, to -4.04, -4.00, and -3.90 for Silicone 1, Silicone 2, and Fluorosilicone 1, respectively), confirming that these sensors retain the high selectivity that makes them suitable for use in physiological samples. When immersed in porcine plasma, the SC-ISEs exhibited emf drifts that were still fairly low but notably larger than when measurements were performed in pure water. Interestingly, despite the very similar structures of these matrix polymers, SC-ISEs prepared with Silicone 2 showed lower drift in porcine blood plasma (-55 µV/h, over 41 h) compared to Silicone 1 (-495 µV/h) or Fluorosilicone 1 (-297 µV/h).


Subject(s)
Plasticizers , Silicones , Animals , Swine , Ion-Selective Electrodes , Water , Polymers , Ions/chemistry
8.
ACS Sens ; 8(4): 1774-1781, 2023 04 28.
Article in English | MEDLINE | ID: mdl-37043696

ABSTRACT

Nanopore-driven sequestration of ionic liquids from a silicone membrane is presented, a phenomenon that has not been reported previously. Reference electrodes with ionic liquid doped polydimethylsiloxane (PDMS) reference membranes and colloid-imprinted mesoporous carbon (CIM) as solid contact are not functional unless special attention is paid to the porosity of the solid contact. In the fabrication of such reference electrodes, a solution of a hydroxyl-terminated silicone oligomer, ionic liquid, cross-linking reagent, and polymerization catalyst is deposited on top of the carbon layer, rapidly filling the pores of the CIM carbon. The catalyzed polymerization curing of the silicone quickly results in cross-linking of the hydroxyl-terminated polydimethylsiloxane oligomers, forming structures that are too large to penetrate the CIM carbon pores. Therefore, as solvent evaporation from the top of freshly prepared membranes drives the diffusional transport of solvent toward that membrane surface, the solvent molecules that leave the CIM carbon pores can only be replaced by the ionic liquid. This depletes the ionic liquid in the reference membrane that overlies the CIM carbon solid contact and increases the membrane resistance by up to 3 orders of magnitude, rendering the devices dysfunctional. This problem can be avoided by presaturating the CIM carbon with ionic liquid prior to the deposition of the solution that contains the silicone oligomers and ionic liquid. Alternatively, a high amount of ionic liquid can be added into the membrane solution to account for the size-selective sequestration of ionic liquid into the carbon pores. Either way, a wide variety of ionic liquids can be used to prepare PDMS-based reference electrodes with CIM carbon as a solid contact. A similar depletion of the K+ ionophore BME-44 from ion-selective silicone membranes was observed too, highlighting that the depletion of active ingredients from polymeric ion-selective and reference membranes due to interactions with high surface area solid contacts may be a more common phenomenon that so far has been overlooked.


Subject(s)
Ionic Liquids , Ionic Liquids/chemistry , Silicones , Solvents , Carbon/chemistry , Electrodes , Dimethylpolysiloxanes
9.
Langmuir ; 39(8): 2890-2910, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36757136

ABSTRACT

Over the past 25 years, the field of colloidal crystal templating of inverse opal or three-dimensionally ordered macroporous (3DOM) structures has made tremendous progress. The degree of structural control over multiple length scales, understanding of mechanical properties, and complexity of systems in which 3DOM materials are a component have increased substantially. In addition, we are now seeing applications of 3DOM materials that make use of multiple features of their architecture at the same time. This Feature Article focuses on the different properties of 3DOM materials that provide functionality, including a relatively large surface area, the interconnectedness of the pores and the resulting good accessibility of the internal surface, the nanostructured features of the walls, the structural hierarchy and periodicity, well-defined surface roughness, and relative mechanical robustness at low density. It provides representative examples that illustrate the properties of interest related to applications including energy storage and conversion systems, sensors, catalysts, sorbents, photonics, actuators, and biomedical materials or devices.

10.
ACS Appl Mater Interfaces ; 14(26): 29832-29843, 2022 Jul 06.
Article in English | MEDLINE | ID: mdl-35735752

ABSTRACT

In Li-excess transition metal-oxide cathode materials, anionic oxygen redox can offer high capacity and high voltages, although peroxo and superoxo species may cause oxygen loss, poor cycling performance, and capacity fading. Previous work showed that undesirable formation of peroxide and superoxide bonds was controlled to some extent by Mn substitution, and the present work uses density functional calculations to examine the reasons for this by studying the anionic redox mechanism in Li8MnO6. This material is obtained by substituting Mn for Sn in Li8SnO6 or for Zr in Li8ZrO6, and we also compare this to previous work on those materials. The calculations predict that Li8MnO6 is stable at room temperature (with a band gap of 3.19 eV as calculated by HSE06 and 1.82 eV as calculated with the less reliable PBE+U), and they elucidate the chemical and structural effects involved in the inhibition of oxygen release in this cathode. Throughout the whole delithiation process, only O2- ions are oxidized. The directional Mn-O bonds formed from unfilled 3d orbitals effectively inhibit the formation of O-O bonds, and the layered structure is maintained even after removing 3 Li per Li8MnO6 formula unit. The calculated average voltage for removal of 3 Li is 3.69 V by HSE06, and the corresponding capacity is 389 mAh/g. The high voltage of oxygen anionic redox and the high capacity result in a high energy density of 1436 Wh/kg. The Li-ion diffusion barrier for the dominant interlayer diffusion path along the c axis is 0.57 eV by PBE+U. These results help us to understand the oxygen redox mechanism in a new lithium-rich Li8MnO6 cathode material and contribute to the design of high-energy density lithium-ion battery cathode materials with favorable electrochemical properties based on anionic oxygen redox.

11.
ACS Omega ; 7(3): 2591-2603, 2022 Jan 25.
Article in English | MEDLINE | ID: mdl-35097257

ABSTRACT

Colchicine, the main active alkaloid from Colchicum autumnale L., is a potent tubulin binder and represents an interesting lead structure for the development of potential anticancer chemotherapeutics. We report on the synthesis and investigation of potentially reactive colchicinoids and their surprising biological activities. In particular, the previously undescribed colchicinoid PT-100, a B-ring contracted 6-exo-methylene colchicinoid, exhibits extraordinarily high antiproliferative and apoptosis-inducing effects on various types of cancer cell lines like acute lymphoblastic leukemia (Nalm6), acute myeloid leukemia (HL-60), Burkitt-like lymphoma (BJAB), human melanoma (MelHO), and human breast adenocarcinoma (MCF7) cells at low nanomolar concentrations. Apoptosis induction proved to be especially high in multidrug-resistant Nalm6-derived cancer cell lines, while healthy human leukocytes and hepatocytes were not affected by the concentration range studied. Furthermore, caspase-independent initiation of apoptosis via an intrinsic pathway was observed. PT-100 also shows strong synergistic effects in combination with vincristine on BJAB and Nalm6 cells. Cocrystallization of PT-100 with tubulin dimers revealed its (noncovalent) binding to the colchicine-binding site of ß-tubulin at the interface to the α-subunit. A pronounced effect of PT-100 on the cytoskeleton morphology was shown by fluorescence microscopy. While the reactivity of PT-100 as a weak Michael acceptor toward thiols was chemically proven, it remains unclear whether this contributes to the remarkable biological properties of this unusual colchicinoid.

12.
J Neurol ; 269(7): 3625-3635, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35099587

ABSTRACT

BACKGROUND: Prognosis of herpetic encephalitis remains severe, with a high proportion of deaths and sequelae. Its treatment is based on acyclovir, but the precise and most effective modalities of this treatment are not established. The objective of this study was to determine them. METHODS: For this, we carried out a descriptive, retrospective, monocentric study, using the current coding database at Marseille University Hospitals. Cohort was intended to be exhaustive for the disease, from January 2000 to June 2019, including patients hospitalized in intensive care and conventional hospitalization sector. Patients (n = 76) included were at least 16 years of age and had a clinical presentation, cerebral Magnetic Resonance Imaging, and/or electroencephalogram abnormalities consistent with herpetic encephalitis confirmed by a positive HSV-PCR in the CSF. Clinical data and treatment, including the doses actually administered to the patient, were compared according to patient's outcome. RESULTS: The mortality rate was 12%, whereas 49% had complete recovery and 39% sequelae impeding independence. Poor outcome was statistically associated with persistence of confusion, aphasia, and impaired consciousness lasting more than 5 days, superinfection, status epilepticus, and length of stay in intensive care unit. A statistical decision tree, constructed using the Classification And Regression Tree model, to prioritize treatment management, showed two main factors that influence the outcome: the patient's weight, and the average daily acyclovir dose actually administered. CONCLUSION: These results suggest to modify acyclovir management in herpetic encephalitis, for low-weight patients (< 79 kg) with a minimum dosage of 2550 mg/day (850 mg/ 8 h), when possible.


Subject(s)
Encephalitis, Herpes Simplex , Acyclovir/therapeutic use , Antiviral Agents/therapeutic use , Body Weight , Disease Progression , Encephalitis, Herpes Simplex/diagnostic imaging , Encephalitis, Herpes Simplex/drug therapy , Humans , Retrospective Studies
13.
Nat Mater ; 20(11): 1456-1458, 2021 11.
Article in English | MEDLINE | ID: mdl-34697425
14.
Medicine (Baltimore) ; 100(31): e26511, 2021 Aug 06.
Article in English | MEDLINE | ID: mdl-34397794

ABSTRACT

ABSTRACT: Pain sensitization leading to polyalgia can be observed during infectious diseases. The blood pressure cuff-evoked pain threshold (BPCEPT) has been used in previous studies as a screening tool for fibromyalgia.We aimed to use the BPCEPT as a screening test for detecting pain sensitization in patients suffering from infectious diseases. We also investigated whether specific factors were associated with pain sensitization.We performed a prospective comparative study including all patients of our infectious diseases center in a 1-year period. We created a positive control group of patients suffering from fibromyalgia and a negative control group of "apparently healthy" patients consulting for vaccination.The blood pressure (BP) cuff was inflated until the patient signaled that they experienced pain, and this pressure value was noted.A total of 2355 patients were included. The positive control group had significantly lower values of the BPCEPT than all other groups. Among hospitalized patients with infectious diseases, a low BPCEPT was significantly associated with high temperature (P < .0001), older age (P = .002), being a woman (P = .004), high serum glutamic-oxaloacetic transaminase (P = .007), and high C reactive protein levels (P = .02). Moreover, in multivariate analysis, respiratory infection, meningitis, urinary tract infection, febrile neutropenia, and Q fever were independently associated with a low BPCEPT. A significant negative dynamic correlation between the BPCEPT and temperature was also observed (P < .001).We demonstrated for the first time in a large sample of patients that the BPCEPT method can be used to detect pain susceptibility. We observed a significant dynamic correlation between pain sensitization and temperature. Additionally, pain sensitization was associated with some diseases, suggesting that they trigger pain sensitivity.


Subject(s)
Blood Pressure Determination , Body Temperature , Infections/complications , Pain/etiology , Age Factors , Aspartate Aminotransferases/blood , Blood Pressure Determination/adverse effects , C-Reactive Protein/metabolism , Disease Susceptibility/diagnosis , Disease Susceptibility/microbiology , Disease Susceptibility/physiopathology , Female , Fibromyalgia/complications , Humans , Infections/physiopathology , Male , Middle Aged , Pain/physiopathology , Pain Threshold , Pressure/adverse effects , Prospective Studies , Risk Factors , Sex Factors
15.
ACS Appl Mater Interfaces ; 13(27): 32126-32135, 2021 Jul 14.
Article in English | MEDLINE | ID: mdl-34213325

ABSTRACT

Metal-ceramic nanocomposites exhibit exceptional mechanical properties with a combination of high strength, toughness, and hardness that are not achievable in monolithic metals or ceramics, which make them valuable for applications in fields such as the aerospace and automotive industries. In this study, interpenetrating nanocomposites of three-dimensionally ordered macroporous (3DOM) tungsten-silicon oxycarbide (W-SiOC) were prepared, and their mechanical properties were investigated. In these nanocomposites, the crystalline tungsten and amorphous silicon oxycarbide phases both form continuous and interpenetrating networks, with some discrete free carbon nanodomains. The W-SiOC material inherits the periodic structure from its 3DOM W matrix, and this periodic structure can be maintained up to 1000 °C. In situ SEM micropillar compression tests demonstrated that the 3DOM W-SiOC material could sustain a maximum average stress of 1.1 GPa, a factor of 22 greater than that of the 3DOM W matrix, resulting in a specific strength of 640 MPa/(Mg/m3) at 30 °C. Deformation behavior of the developed 3DOM nanocomposite in a wide temperature range (30-575 °C) was investigated. The deformation mode of 3DOM W-SiOC exhibited a transition from fracture-dominated deformation at low temperatures to plastic deformation above 425 °C.

16.
Front Immunol ; 12: 625732, 2021.
Article in English | MEDLINE | ID: mdl-34194422

ABSTRACT

The etiological agent of COVID-19 SARS-CoV-2, is primarily a pulmonary-tropic coronavirus. Infection of alveolar pneumocytes by SARS-CoV-2 requires virus binding to the angiotensin I converting enzyme 2 (ACE2) monocarboxypeptidase. ACE2, present on the surface of many cell types, is known to be a regulator of blood pressure homeostasis through its ability to catalyze the proteolysis of Angiotensin II (Ang II) into Angiotensin-(1-7) [Ang-(1-7)]. We therefore hypothesized that SARS-CoV-2 could trigger variations of ACE2 expression and Ang II plasma concentration in SARS-CoV-2-infected patients. We report here, that circulating blood cells from COVID-19 patients express less ACE2 mRNA than cells from healthy volunteers. At the level of circulating cells, this ACE2 gene dysregulation mainly affects the monocytes, which also show a lower expression of membrane ACE2 protein. Moreover, soluble ACE2 (sACE2) plasma concentrations are lower in prolonged viral shedders than in healthy controls, while the concentration of sACE2 returns to normal levels in short viral shedders. In the plasma of prolonged viral shedders, we also found higher concentrations of Ang II and angiotensin I (Ang I). On the other hand, the plasma levels of Ang-(1-7) remains almost stable in prolonged viral shedders but seems insufficient to prevent the adverse effects of Ang II accumulation. Altogether, these data evidence that the SARS-CoV-2 may affect the expression of blood pressure regulators with possible harmful consequences on COVID-19 outcome.


Subject(s)
Angiotensin II/blood , Angiotensin I/blood , Angiotensin-Converting Enzyme 2/blood , COVID-19/blood , Peptide Fragments/blood , Adult , Angiotensin-Converting Enzyme 2/genetics , COVID-19/virology , Female , Gene Expression Profiling , HLA-DR Antigens , Humans , Lipopolysaccharide Receptors , Male , Middle Aged , Monocytes/immunology , Monocytes/metabolism , Pilot Projects , Prospective Studies , RNA, Messenger , Virus Shedding
17.
ACS Appl Mater Interfaces ; 12(44): 49971-49981, 2020 Nov 04.
Article in English | MEDLINE | ID: mdl-33079519

ABSTRACT

Metal-organic framework (MOF) materials have shown promise in many applications, ranging from gas storage to absorption and catalysis. Because of the high porosity and low density of many MOFs, densification methods such as pelletization and extrusion are needed for practical use and for commercialization of MOF materials. Therefore, it is important to elucidate the mechanical properties of MOFs and to develop methods of further enhancing their mechanical strength. Here, we demonstrate the influence of phase purity and the presence of a pore-reinforcing component on elastic modulus and yield stress of NU-1000 MOFs through nanoindentation methods and finite element simulation. Three types of NU-1000 single crystals were compared: phase-pure NU-1000 prepared with biphenyl-4-carboxylic acid as a modulator (NU-1000-bip), NU-1000 prepared with benzoic acid as a modulator (NU-1000-ben), which results in an additional, denser impurity phase of NU-901, and NU-1000-bip whose mesopores were infiltrated with silica (SiOx(OH)y@NU-1000) by nanocasting methods. By maintaining phase purity and minimizing defects, the elastic modulus could be enhanced by nearly an order of magnitude: phase-pure NU-1000-bip crystals exhibited an elastic modulus of 21 GPa, whereas the value for NU-1000-ben crystals was only 3 GPa. The introduction of silica into the mesopores of NU-1000-bip did not strongly affect the measured elastic modulus (19 GPa) but significantly increased the load at failure from 2000 µN to 3000-4000 µN.

18.
Eur Geriatr Med ; 11(4): 623-633, 2020 08.
Article in English | MEDLINE | ID: mdl-32681458

ABSTRACT

INTRODUCTION: Hip and knee arthroplasties are the most common planned orthopedic surgical procedures in older persons. It would be useful to identify frailties before surgery to improve the outcome of older patients. PURPOSE: The objective of this work was to identify the criteria of a simplified comprehensive geriatric assessment (mini-CGA) that were associated with unplanned hospital readmission and postoperative complications within 3 months after the planned hip and/or knee arthroplasty in patients ≥ 65 years. METHODS: This prospective study was carried out in the orthopedic department of Marseille University Hospital from January to May 2019. A mini-CGA was performed preoperatively. RESULTS: One hundred four patients were included in the study. The rate of early readmission within 3 months after surgery was 12.5% and the rate of postoperative complications was 40.4%. In multivariate analysis, dependence in the activities of daily living (ADL ≤ 5) was the only factor associated with unplanned readmission (aOR = 9.9, 95% CI 1.9-50.8), and living alone was the only factor associated with postoperative complications (aOR = 3.2, 95% CI 1.2-8.8). CONCLUSIONS: We found that the ADL score was associated with the risk of unplanned readmission in older patients undergoing planned arthroplasty, and that living alone was associated with postoperative complications. A preoperative mini-CGA appears essential to limit postoperative morbidity.


Subject(s)
Arthroplasty, Replacement, Hip , Arthroplasty, Replacement, Knee , Activities of Daily Living , Aged , Aged, 80 and over , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Knee/adverse effects , Geriatric Assessment , Humans , Prospective Studies
19.
Travel Med Infect Dis ; 36: 101791, 2020.
Article in English | MEDLINE | ID: mdl-32593867

ABSTRACT

BACKGROUND: In our institute in Marseille, France, we initiated early and massive screening for coronavirus disease 2019 (COVID-19). Hospitalization and early treatment with hydroxychloroquine and azithromycin (HCQ-AZ) was proposed for the positive cases. METHODS: We retrospectively report the clinical management of 3,737 screened patients, including 3,119 (83.5%) treated with HCQ-AZ (200 mg of oral HCQ, three times daily for ten days and 500 mg of oral AZ on day 1 followed by 250 mg daily for the next four days, respectively) for at least three days and 618 (16.5%) patients treated with other regimen ("others"). Outcomes were death, transfer to the intensive care unit (ICU), ≥10 days of hospitalization and viral shedding. RESULTS: The patients' mean age was 45 (sd 17) years, 45% were male, and the case fatality rate was 0.9%. We performed 2,065 low-dose computed tomography (CT) scans highlighting lung lesions in 592 of the 991 (59.7%) patients with minimal clinical symptoms (NEWS score = 0). A discrepancy between spontaneous dyspnoea, hypoxemia and lung lesions was observed. Clinical factors (age, comorbidities, NEWS-2 score), biological factors (lymphocytopenia; eosinopenia; decrease in blood zinc; and increase in D-dimers, lactate dehydrogenase, creatinine phosphokinase, troponin and C-reactive protein) and moderate and severe lesions detected in low-dose CT scans were associated with poor clinical outcome. Treatment with HCQ-AZ was associated with a decreased risk of transfer to ICU or death (Hazard ratio (HR) 0.18 0.11-0.27), decreased risk of hospitalization ≥10 days (odds ratios 95% CI 0.38 0.27-0.54) and shorter duration of viral shedding (time to negative PCR: HR 1.29 1.17-1.42). QTc prolongation (>60 ms) was observed in 25 patients (0.67%) leading to the cessation of treatment in 12 cases including 3 cases with QTc> 500 ms. No cases of torsade de pointe or sudden death were observed. CONCLUSION: Although this is a retrospective analysis, results suggest that early diagnosis, early isolation and early treatment of COVID-19 patients, with at least 3 days of HCQ-AZ lead to a significantly better clinical outcome and a faster viral load reduction than other treatments.


Subject(s)
Antiviral Agents/therapeutic use , Azithromycin/therapeutic use , Betacoronavirus , Coronavirus Infections/drug therapy , Hydroxychloroquine/therapeutic use , Pneumonia, Viral/drug therapy , Adult , COVID-19 , Coronavirus Infections/mortality , Coronavirus Infections/virology , Female , France/epidemiology , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/mortality , Pneumonia, Viral/virology , Retrospective Studies , SARS-CoV-2 , Treatment Outcome , COVID-19 Drug Treatment
20.
Travel Med Infect Dis ; 35: 101738, 2020.
Article in English | MEDLINE | ID: mdl-32387409

ABSTRACT

BACKGROUND: In France, the combination hydroxychloroquine (HCQ) and azithromycin (AZ) is used in the treatment of COVID-19. METHODS: We retrospectively report on 1061 SARS-CoV-2 positive tested patients treated for at least three days with the following regimen: HCQ (200 mg three times daily for ten days) + AZ (500 mg on day 1 followed by 250 mg daily for the next four days). Outcomes were death, clinical worsening (transfer to ICU, and >10 day hospitalization) and viral shedding persistence (>10 days). RESULTS: A total of 1061 patients were included in this analysis (46.4% male, mean age 43.6 years - range 14-95 years). Good clinical outcome and virological cure were obtained in 973 patients within 10 days (91.7%). Prolonged viral carriage was observed in 47 patients (4.4%) and was associated to a higher viral load at diagnosis (p < .001) but viral culture was negative at day 10. All but one, were PCR-cleared at day 15. A poor clinical outcome (PClinO) was observed for 46 patients (4.3%) and 8 died (0.75%) (74-95 years old). All deaths resulted from respiratory failure and not from cardiac toxicity. Five patients are still hospitalized (98.7% of patients cured so far). PClinO was associated with older age (OR 1.11), severity of illness at admission (OR 10.05) and low HCQ serum concentration. PClinO was independently associated with the use of selective beta-blocking agents and angiotensin II receptor blockers (p < .05). A total of 2.3% of patients reported mild adverse events (gastrointestinal or skin symptoms, headache, insomnia and transient blurred vision). CONCLUSION: Administration of the HCQ+AZ combination before COVID-19 complications occur is safe and associated with a very low fatality rate in patients.


Subject(s)
Antiviral Agents/therapeutic use , Azithromycin/therapeutic use , Betacoronavirus/genetics , Coronavirus Infections/drug therapy , Hydroxychloroquine/therapeutic use , Pneumonia, Viral/drug therapy , Adolescent , Adult , Aged , Aged, 80 and over , Antiviral Agents/administration & dosage , Antiviral Agents/adverse effects , Azithromycin/administration & dosage , Azithromycin/adverse effects , COVID-19 , Coronavirus Infections/mortality , Coronavirus Infections/virology , Drug Therapy, Combination , Female , Follow-Up Studies , France , Humans , Hydroxychloroquine/administration & dosage , Hydroxychloroquine/adverse effects , Male , Middle Aged , Pandemics , Pneumonia, Viral/mortality , Pneumonia, Viral/virology , Polymerase Chain Reaction , Retrospective Studies , SARS-CoV-2 , Time Factors , Treatment Outcome , Viral Load , Young Adult , COVID-19 Drug Treatment
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