[Efficacy of dupilumab in real practice in the treatment of severe forms of asthma and atopic dermatitis (comparative retrospective study)]

BACKGROUND

Dupilumab, a fully human monoclonal antibody directed against the common α-subunit of interleukin (IL)-4 receptors and blocking signaling from both IL-4 and IL-13, may be recommended for the treatment of moderate to severe atopic dermatitis (AD) and bronchial asthma (BA).

AIM

To perform a comparative assessment of the effectiveness of maintenance therapy with dupilumab in patients with severe BA as the main indication for genetically engineered biological drugs and in patients with severe asthma with concomitant severe AD as the indication for targeted therapy.

MATERIALS AND METHODS

A 6-month retrospective comparative study was performed at the specialized reference center for allergology and immunology. The study included 115 adult patients of both sexes treated with dupilumab for uncontrolled severe asthma as the main indication for targeted therapy (BA group; n=65) or for a combination of severe uncontrolled asthma and severe AD (BAAD; n=50). Dupilumab was administered subcutaneously for 6 months. The first dose was 600 mg once and then 300 mg Q2W. Evaluation of the effectiveness of dupilumab therapy at 6 months of treatment in both groups included achieving asthma control (ACT, ACQ5), improving pulmonary function test, reducing the risk of exacerbations and the need for systemic glucocorticosteroids (SGCS), improving quality of life (AQLQ), change of biomarkers (FeNO, eosinophil count) and the course of comorbid diseases, including improvement in the AD (SCORAD, EASI) and rhinosinusitis polyposa (SNOT-22).

RESULTS AND CONCLUSION

During dupilumab therapy, in a significant proportion of patients, regardless of the presence or absence of other T2-associated diseases (e.g., AD or rhinosinusitis polyposa), an improvement in asthma was demonstrated as early as in the first 6 months of treatment with dupilumab in all recommended domains for assessing the response to targeted therapy: improving asthma control and respiratory function, reducing the frequency of moderate and severe exacerbations associated with the use of SGCS and/or hospitalization, a positive effect on the quality of life and the comorbid diseases, as well as a cumulative reduction in the need for SGCS.

Peculiarities of radioactive soil contamination in places of underground nuclear tests in the Semipalatinsk test site

The article highlights the results of a radioecological survey of the surface areas of combat boreholes at the Sary-Uzen site located on the territory of the Semipalatinsk Test Site (STS), where underground nuclear tests in these boreholes were conducted earlier. The surface areas of boreholes were examined the levels of radioactive contamination of the soil were determined. A total of 2 main groups were identified. The first group includes boreholes with radioactive contamination of the soil on the surface area. The second group includes boreholes with no radioactive contamination of the surface soil layer. The first group can be divided into boreholes with a deformation of the ground surface and without it. For each variety, depending on the specifics of the nuclear test, the characteristic features of radioactive contamination were determined. Based on the results of the survey, the ranges of specific activity values were established.

Changes in anticoagulant prescription in a general hospital in 2008-2018

Aim. To study the structure of anticoagulant prescription in a general hospital to identify trends and contributing factors.

Materials and methods. The study was conducted in an urban general hospital. According to retrospective retrieval from electronic health records, total 17,129 patients received anticoagulants from 2008 to 2018. Formal appropriateness of oral anticoagulants (OАС) prescriptions for 6,638 patients with atrial fibrillation (AF) was analyzed with CHA2-DS2-VASc score.

Results. Appearance of recommendations for the direct oral anticoagulants (DOAC) prescription in clinical guidelines for venous thromboembolism (VTE) and AF management contributed to steady increase in the DOAC taking and decrease in the proportion of warfarin prescription. From 2011 to 2018, the proportion of patients with DOACs prescription increased from 1.7% to 81.5%. The most common indications for anticoagulant were ischemic stroke prevention in AF and VTE with mean rate 75.3% and 23.2%, respectively for the 2011-2018 period. Steady increase in low-molecular-weight heparin (LMWH) prophylactic prescriptions was also shown (Chi-square for linear trend=1340, df=1, p<0.0001). Since 2014, the prescription of LMWH in prophylactic doses increased dramatically, probably related to implementation of computerized decision support system (CDSS) for VTE prevention in the hospital.

Conclusion. The study showed that in a general hospital anticoagulants were prescribed in 19% of hospitalized patient. Not only the new clinical recommendations based on the results of the recent studies on anticoagulants efficacy and safety (external factors), but also implementation standard operating protocols and CDSS, providing physicians current information about the relevant clinical recommendations (internal changes), could influence the appropriateness of anticoagulants prescription.

[Results of decision support system implementation for prescribing anticoagulants to patients with atrial fibrillation in hospital]

BACKGROUND

In 819% of patients with atrial fibrillation (AF) with anticoagulant therapy (ACT), hemorrhagic complications occur, including due to excess doses of AC. At the same time, ACT is necessary for patients with AF, since anticoagulants effectively reduces the risk of ischemic stroke. To make a decision on the appointment of ACT, it is necessary to correlate the risks of ischemic stroke and bleeding, this requires knowledge of current clinical using ACT recommendations and instructions. Among patients admitted to hospital, 30% receive ACT, so increasing adherence to clinical recommendations for prescribing AC to patients with AF by doctors of various profiles is an urgent task.

AIM

To analyze the adherence of physicians to recommendations for prescribing ACT before and after the introduction of decision support system (DSS) in patients with AF in a multi-specialty hospital.

MATERIALS AND METHODS

A single-center non-randomized study with historical control to assess adherence to recommendations based on the analysis of medical prescriptions and the structure of drug errors in patients with AF in a multi-specialty hospital in Moscow before and after the introduction of DSS. Compliance with the recommendations of physicians was evaluated in the sections indications /contraindications to AC and dosage regimen of AC. The presence of deviations from the clinical recommendations /instructions for medical use of AC was regarded as management of the patient with non-compliance with recommendations. Physicians adherence level to recommendations was calculated as the ratio of cases of compliance with recommendations to the total number of cases.

RESULTS

In the control and experimental groups, there was a significant increase in the proportion of POAC at discharge in comparison with admission to hospital: from 54.5 to 76.8% (p=0.0005) and from 63 to 85.7% (p=0.0002), respectively. However, only in the experimental group it was possible to significantly reduce the number of patients without a prescribed ACT (if there are indications) from 7.6 to 1% (p=0.04) in comparison with admission. During the study, it was possible to significantly increase physicians adherence level to the recommendations for the AC dosage regimen in patients with AF from 59% (44 discrepancies for 107 prescriptions) to 84.6% (16 discrepancies for 104 prescriptions); p0.005. Before the introduction of the DSS, the analysis of drug prescriptions revealed 56 drug errors (0.5 errors per patient), after the introduction of the DSS, the number of drug errors significantly decreased to 21 (0.2 errors per patient); p0.05. After the introduction of DSS, the number of sub-therapeutic doses of AC was reduced from 31 (27.7%) to 8 (7.6%); p0.05.

CONCLUSION

The level of adherence to the recommendations for prescribing ACT to patients with AF in the hospital is high. The use of DSS increases the level of adherence to the recommendations on the AC dosage regimen in patients with AF, as well as eliminates errors in calculating the risk of ischemic stroke and systemic thromboembolic complications, and contributes to reducing the frequency of prescribing sub-therapeutic doses of AC.

[Thrombectomy for acute iliofemoral thrombosis in prevention of pulmonary embolism]

BACKGROUND

Acute thrombosis in the system of the inferior vena cava is one of the most common vascular diseases and is of serious danger as a potential source of one of the most severe complications. In order to assess efficacy of open thrombectomy for embologenic iliofemoral venous thromboses we carried out comparison of the results of open thrombectomy and implantation of cava filters in a total of 119 patients presenting with iliofemoral thrombosis.

PATIENTS AND METHODS

Open thrombectomy was performed in a total of 59 patients. Of these, 12 patients with segmental thromboses underwent radical thrombectomy and 47 patients with disseminated forms of thrombosis were subjected to partial thrombectomy with plication of the femoral vein. In 5 patients, the operation was supplemented with applying an arteriovenous fistula. Efficacy of operations was assessed with the help of ultrasonographic duplex angioscanning and regression of clinical manifestations. In the remote period, the degree of manifestations of post-thrombotic disease was assessed by means of the Villalta scale.

RESULTS

After radical thrombectomy, patency of the iliofemoral segment was preserved in all patients during the whole follow-up period. In the group of patients with partial thrombectomy, 5 (9.5%) patients developed rethrombosis above the placation site at terms from 8 to 12 months. Four-year patency of the iliofemoral segment in this group of patients amounted to 81.5%. In patients with implanted cava filters, neither femoral vein nor iliac segment were patent completely. During the first year, thrombosis of cava filter developed in 9 cases; after 2 years, occlusion of the cava filter was diagnosed in 7 patients. In clinical assessment of the remote results with the use of the Villalta scale in patients after open thrombectomy the symptoms of post-traumatic disease were absent or weakly pronounced. After implantation of the cava filter all patients demonstrated the clinical course of post-traumatic disease, corresponding to 10-15 points.

CONCLUSION

Open thrombectomy for iliofemoral embologenic thromboses performed at specialized departments is a radical method of preventing thromboembolic complications and promotes restoration or improvement of venous blood flow in the extremity.

Extraction of effective solid-liquid interfacial free energies for full 3D solid crystallites from equilibrium MD simulations

Molecular dynamics simulations of an embedded atom copper system in the isobaric-isenthalpic ensemble are used to study the effective solid-liquid interfacial free energy of quasi-spherical solid crystals within a liquid. This is within the larger context of molecular dynamics simulations of this system undergoing solidification, where single individually prepared crystallites of different sizes grow until they reach a thermodynamically stable final state. The resulting equilibrium shapes possess the full structural details expected for solids with weakly anisotropic surface free energies (in these cases, ∼5% radial flattening and rounded [111] octahedral faces). The simplifying assumption of sphericity and perfect isotropy leads to an effective interfacial free energy as appearing in the Gibbs-Thomson equation, which we determine to be ∼177 erg/cm², roughly independent of crystal size for radii in the 50-250 Å range. This quantity may be used in atomistically informed models of solidification kinetics for this system.

Effect of wetting on nucleation and growth of D2 in confinement

We have performed a computational study to determine how the wetting of liquid deuterium to the walls of the material influences nucleation. We present the development of a pair-wise interatomic potential that includes zero-point motion of molecular deuterium. Deuterium is used in this study because of its importance to inertial confinement fusion and the potential to generate a superfluid state if the solidification can be suppressed. Our simulations show that wetting dominates undercooling compared to the pore geometries. We observe a transition from heterogeneous nucleation at the confining wall to homogeneous nucleation at the bulk of the liquid (and intermediate cases) as the interaction with the confining wall changes from perfect wetting to non-wetting. When nucleation is heterogeneous, the temperature needed for solidification changes by 4 K with decreasing deuterium-wall interaction, but it remains independent (and equal to the one from bulk samples) when homogeneous nucleation dominates. We find that growth and quality of the resulting microstructure also depends on the magnitude of liquid deuterium-wall interaction strength.

[The effect of heterozygosity for marker loci on recombination fraction in adjacent chromosomal regions in maize]

Analysis of maize F2 plants revealed a decrease in the recombination fraction (rf) between the marker loci in case of heterozygosity of adjacent chromosomal regions. The relative decrease in rf was positively associated with the length of the heterozygous region. Heterozygosity had no effect on rf in other chromosomes. These results can be explained by defective pairing of heterozygous chromosomal regions in meiosis.

Diffraction and imaging study of imperfections of crystallized lysozyme with coherent X-rays

Phase-contrast X-ray diffraction imaging and high-angular-resolution diffraction combined with phase-contrast radiographic imaging were employed to characterize defects and perfection of a uniformly grown tetragonal lysozyme crystal in the symmetric Laue case. The full-width at half-maximum (FWHM) of a 4 4 0 rocking curve measured from the original crystal was approximately 16.7 arcsec and imperfections including line defects, inclusions and other microdefects were observed in the diffraction images of the crystal. The observed line defects carry distinct dislocation features running approximately along the <1 1 0> growth front and have been found to originate mostly in a central growth area and occasionally in outer growth regions. Inclusions of impurities or formations of foreign particles in the central growth region are resolved in the images with high sensitivity to defects. Slow dehydration led to the broadening of a fairly symmetric 4 4 0 rocking curve by a factor of approximately 2.6, which was primarily attributed to the dehydration-induced microscopic effects that are clearly shown in X-ray diffraction images. The details of the observed defects and the significant change in the revealed microstructures with drying provide insight into the nature of imperfections, nucleation and growth, and the properties of protein crystals.

Surface relaxation in protein crystals

Surface x-ray diffraction measurements were performed on (111) growth faces of crystals of the cellular iron-storage protein, horse spleen ferritin. Crystal truncation rods (CTR) were measured. A fit of the measured profile of the CTR revealed a surface roughness of 48+/-4.5 A and a top layer spacing contraction of 3.9+/-1.5%. In addition to the peak from the CTR, the rocking curves of the crystals displayed unexpected extra peaks. Multiple scattering is demonstrated to account for them. Future applications of the method could allow the exploration of hydration effects on the growth of protein crystals.

View on biocrystallization from Jena, 2002

An introductory report of the ICCBM9 meeting in Jena, Germany, 2002, is given.

Phase sensitive x-ray diffraction imaging of defects in biological macromolecular crystals

Conventional x-ray diffraction topography is currently used to map defects in the bulk of protein crystals, but the lack of sufficient contrast is frequently a limiting factor. We experimentally demonstrate that this barrier can be circumvented using a method that combines phase sensitive and diffraction imaging principles. Details of defects revealed in tetragonal lysozyme and cubic ferritin crystals are presented and discussed. The approach enabling the detection of the phase changes of diffracted x rays should prove to be useful in the study of defect structures in a broad range of biological macromolecular crystals.

Laboratory multiple-crystal X-ray topography and reciprocal-space mapping of protein crystals: influence of impurities on crystal perfection

Double-axis multiple-crystal X-ray topography, rocking-curve measurements and triple-axis reciprocal-space mapping have been combined to characterize protein crystals using a laboratory source. Crystals of lysozyme and lysozyme crystals doped with acetylated lysozyme impurities were examined. It was shown that the incorporation of acetylated lysozyme into crystals of lysozyme induces mosaic domains that are responsible for the broadening and/or splitting of rocking curves and diffraction-space maps along the direction normal to the reciprocal-lattice vector, while the overall elastic lattice strain of the impurity-doped crystals does not appear to be appreciable in high angular resolution reciprocal-space maps. Multiple-crystal monochromatic X-ray topography, which is highly sensitive to lattice distortions, was used to reveal the spatial distribution of mosaic domains in crystals which correlates with the diffraction features in reciprocal space. Discussions of the influence of acetylated lysozyme on crystal perfection are given in terms of our observations.

Macromolecular impurities and disorder in protein crystals

The mechanisms by which macromolecular impurities degrade the diffraction properties of protein crystals have been investigated using X-ray topography, high-resolution diffraction line shape measurements, crystallographic data collection, chemical analysis, and two-photon excitation fluorescence microscopy. Hen egg-white lysozyme crystals grown from solutions containing a structurally unrelated protein (ovotransferrin) and a related protein (turkey egg-white lysozyme) can exhibit significantly broadened mosaicity due to formation of cracks and dislocations but have overall B factors and diffraction resolutions comparable to those of crystals grown from uncontaminated lysozyme. Direct fluorescence imaging of the three-dimensional impurity distribution shows that impurities incorporate with different densities in sectors formed by growth on different crystal faces, and that impurity densities in the crystal core and along boundaries between growth sectors can be much larger than in other parts of the crystal. These nonuniformities create stresses that drive formation of the defects responsible for the mosaic broadening. Our results provide a rationale for the use of seeding to obtain high-quality crystals from heavily contaminated solutions and have implications for the use of crystallization for protein purification. Proteins 1999;36:270-281.

Refined structure of orthorhombic lysozyme crystallized at high temperature: correlation between morphology and intermolecular contacts

The structure of orthorhombic hen egg-white lysozyme (HEWL) crystallized at 310 K has been refined at 1.7 A resolution. Large displacements of the side-chain atoms with respect to the tetragonal structure were observed in many places, in contrast to small displacements of the main-chain atoms. A chloride-ion binding site was observed at an interface of two molecules, but at a different position to the binding site in the tetragonal form. The analysis of intermolecular contacts in the crystal has shown the presence of three independent intermolecular contacts which are called macrobonds A, B and C. Arginine side chains are frequently involved in these macrobonds, suggesting that the high frequency of this residue in HEWL may be a possible reason for the multiple polymorphs of this protein. The crystal forms were determined using a light-reflecting device on a four-circle diffractometer. Correlations between crystal forms and the three-dimensional macrobond networks were interpreted in terms of their components in various crystallographic planes, making use of approximate strengths of hydrogen-bond and van der Waals interatomic forces.

Crystal growth and crystallography

Selected topics that may be of interest for both crystal-structure and crystal-growth communities are overviewed. The growth of protein crystals, along with that of some other compounds, is one of the topics, and recent insights into related phenomena are considered as examples of applications of general principles. The relationship between crystal growth shape and structure is reviewed and an attempt to introduce semiquantitative characterization of binding for proteins is made. The concept of kinks for complex structures is briefly discussed. Even at sufficiently low supersaturations, the fluctuation of steps may not be sufficient to implement the Gibbs-Thomson law if the kink density is low enough. Subsurface ordering of liquids and growth of rough interfaces from melts is discussed. Crystals growing in microgravity from solution should be more perfect if they preferentially trap stress-inducing impurities, thus creating an impurity-depleted zone around themselves. Evidently, such a zone is developed only around the crystals growing in the absence of convection. Under terrestrial conditions, the self-purified depleted zone is destroyed by convection, the crystal traps more impurity and grows stressed. The stress relief causes mosaicity. In systems containing stress-inducing but poorly trapped impurities, the crystals grown in the absence of convection should be worse than those of their terrestrial counterparts.

Terrestrial and space-grown HAP and OCP crystals: effect of growth conditions on perfection and morphology

This paper reports comparative characterizations of calcium phosphate crystals grown on earth and in space. At the CaCl2 and KH2PO4 + K2HPO4 solution concentrations and the pH used, only hydroxyapatite (HAP) crystals grow under terrestrial condition while both HAP and octacalcium phosphate (OCP) crystals grew during the space experiment. The space-grown OCP crystals reach 3 mm in size, the space-grown HAP crystals reach sizes up to 100 times larger than the earth-grown crystallites. It was found also that the space-grown crystallites are more perfect than the terrestrial ones, being more stable under electron beam during HRTEM examination. Spherolites of hydroxyapatite consist of small and thin HAP crystals with different orientations. Space-grown OCP crystals containing almost pure OCP phase show strong striations along the c direction due to thickness variations. Terrestrial OCP crystals grown at lowest supersaturation on earth may be almost as large as the space-grown ones, possess a regular habit and are homogeneous in thickness. However, they always contain substantial regions of HAP structure. Also, in these crystals electron irradiation induces phase transformation from crystalline to amorphous (disordered) state during transmission electron microscopy observations. In the space-grown crystals, such transformation needs longer radiation time. We believe that the differences described above come from much lower supersaturation and different pH for crystals nucleating and growing in space compared to those formed on earth.

Calcium phosphate crystallization under terrestrial and microgravity conditions

Calcium phosphate crystalline powders grown under terrestrial and space (EURECA 1992-1993 flight) conditions in the Solution Growth Facility are analyzed and compared by optical and electron microscopy (scanning and transmission), electron and X-ray microdiffraction and microanalyses. On earth, only small, micrometer size scale, spherolites of hydroxyapatite (HAP) grow. In space, the HAP spherolites reach hundreds of micrometer. Also, octacalcium phosphate (OCP) spherolites up to 3 mm have been obtained. Computer modelling of diffusion in a real chamber has been performed. It suggests high spatial supersaturation gradients at zero gravity which may provide much higher local supersaturations on earth, where convection takes place. The analyses suggest that the dramatic difference between the terrestrial and space samples should come from much lower supersaturation in space.

Crystallization of calcium phosphate in microgravity

Dilute solutions of CaCl2 and KH2PO4 + K2HPO4 were diffusing from either side into a mixing chamber with KCl solution. The microgravity experiment yielded aggregates of large crystals of OCP (Ca8H2(PO4)3,5H2O) and spherolites of smaller, but still visible crystals of HAP (Ca5OH(PO4)3), the stable final phase. Ground-based experiments yielded submicroscopic HAP crystals. Results of calculations of diffusion and crystal growth on the basis of previous knowledge agree well with observations.