Theoretical and experimental study of high-pressure synthesized B20-type compounds Mn1−x_{1-x}(Co,Rh)x_xGe

The search and exploration of new materials not found in nature is one of modern trends in pure and applied chemistry. In the present work, we report on experimental and \textit{ab initio} density-functional study of the high-pressure-synthesized series of compounds Mn$_{1-x}$(Co,Rh)$_x$Ge. These high-pressure phases remain metastable at normal conditions, therewith they preserve their inherent noncentrosymmetric B20-type structure and chiral magnetism. Of particular interest in these two isovalent systems is the comparative analysis of the effect of $3d$ (Co) and $4d$ (Rh) substitution for Mn, since the $3d$ orbitals are characterized by higher localization and electron interaction than the $4d$ orbitals. The behavior of Mn$_{1-x}$(Co,Rh)$_x$Ge systems is traced as the concentration changes in the range $0 \leq x \leq 1$. We applied a sensitive experimental and theoretical technique which allowed to refine the shape of the temperature dependencies of magnetic susceptibility $\chi(T)$ and thereby provide a new and detailed magnetic phase diagram of Mn$_{1-x}$Co$_x$Ge. It is shown that both systems exhibit a helical magnetic ordering that very strongly depends on the composition $x$. However, the phase diagram of Mn$_{1-x}$Co$_x$Ge differs from that of Mn$_{1-x}$Rh$_x$Ge in that it is characterized by coexistence of two helices in particular regions of concentrations and temperatures.Comment: 12 pages, 11 figure

Stability of vacancy-free crystalline phases of titanium monoxide at high pressure and temperature

There has existed for a long time a paradigm that TiO phases at ambient conditions are stable only if structural vacancies are available. Using an evolutionary algorithm, we perform an ab initio search of possible zero-temperature polymorphs of TiO in wide pressure interval. We obtain the Gibbs energy of the competing phases taking into account entropy via quasiharmonic approximation and build the pressure–temperature diagram of the system. We reveal that two vacancy-free hexagonal phases are the most stable at relatively low temperatures in a wide range of pressures. The transition between these phases takes place at 28 GPa. Only above 1290 K at ambient pressure the phases with vacancies (B1-derived) become stable. In particular, the high-pressure hexagonal phase is shown to have unusual electronic properties, with a pronounced pseudo-gap in the electronic spectrum. The comparison of DFT–GGA and GW calculations demonstrates that the account for many-body corrections significantly changes the electronic spectrum near the Fermi energy. © 2020, EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature

COMBINED FEMORAL FIXATION TECNIQUE IN HAMSTRING TENDON ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION: ASESSMENT OF TUNNEL WIDENING

Purpose – to assess the influence of combined femoral fixation technique during arthroscopic ACL reconstruction on the femoral tunnel widening at long term follow-up.Material and methods. 99 patients with primary hamstring tendon (HT) ACL reconstruction performed in 2007-2008 were analyzed. In the study group (42 patients) on the femoral side a combined cortical suspension (Endobutton CL, Smith & Nephew) and transverse (Rigid Fix, Depuy Mitek) fixation of graft was used. In control group, isolated cortical suspension fixation (Endobutton CL, Smith & Nephew) was used. On the tibial side for graft fixation a biodegradable screw (Biointrafix, DePuy Mitek) was used in all cases. Tunnel widening was calculated in percentage against primary tunnel diameter created during the surgery. MRI data were exported to eFilm (Merge Healthcare software), measurement of femoral tunnel diameters was performed on T1 sequences in coronal and sagittal planes on three different levels.Results. The mean age at the last follow up in the study group was 38.9±1.4, in control group – 38,6±1,08. The median time from surgery to follow up was 9 years and 4 months in the study group and 8 years 7 months in the controls. The incidence of graft failure in the study group was reported as 14.3%, while in the control group as 17,5%. The median femoral tunnel widening was larger in the control group at the joint aperture and midsection levels both in coronal and sagittal plane, although there was no statistically significant differences (p>0,05).Conclusion. The combination of cortical suspension and transverse HT femoral graft fixation technique is likely to reduce tunnel enlargement at the long term follow-up. However further research and larger sample groups are required

Stabilization of acromioclavicular joint using DogBone dynamic system (Arthrex): a literature review and long-term follow-up

Objectives The purpose of the study was to evaluate long-term follow-ups of stabilized acromioclavicular joint (ACJ) dislocations using button dynamic system applied via arthroscopic technique or mini-open. Material and methods The review included follow-ups of 40 patients (39 males, 1 female) who underwent 40 ACJ stabilization procedures with Arthrex DogBone button between 2014 and 2017 using arthroscopy (n = 28) or mini-open technique (n = 12). The mean age of the patients was 34 years (range, 15 to 59 years). Patient reported outcomes were evaluated with UCLA shoulder rating scale, American Shoulder and Elbow Surgeons (ASES) shoulder score and the Constant Shoulder Score (CSS). Coraco-Clavicular Distance (ССD) was measured on preand postoperative anteroposterior views. Postoperative AP view was used to measure Clavicular Tunnel Distance (CTD). Arthroscopy patients had available preoperative radiographs (n = 21), postoperative radiographs (n = 26) and patient reported outcomes (n = 18). Mini open group had available preoperative radiographs (n = 2), postoperative radiographs (n=8) and patient reported outcomes (n = 8). Results One hundred percent of Arthroscopy/Mini open (26/26) cases were rated as excellent and good on UCLA shoulder rating scale at a long-term follow-up. One hundred percent of Arthroscopy patients (18/18) were rated as excellent and good; 75 % (6/8) of Mini-open cases evaluated as excellent and 25 % (2/8) as good on ASES shoulder score. Sixty seven percent of Arthroscopy (12/18) patients were rated as excellent and 33 % (6/18) as good; 62 % (5/8) of Mini open cases evaluated as excellent and 38 % (3/8) as good. Neither fair nor poor results were observed in both groups. No statistically significant differences were detected in median scores between Arthroscopy and Miniopen groups (p > 0.05). Preoperative radiographs showed Tossy grade IV dislocation (n = 3) and Tossy grade III (n = 20). Distal clavicle fracture was diagnosed in 2 cases. Median preoperative CCD radiologically measured 15.5 mm in both groups (n = 23). Median postoperative CCD and CTD radiologically measured 6.12 mm and 28.9 mm in both groups (n = 35), correspondingly. Decrease in postoperative CCD was significantly different (p = 0.0003). No statistically significant differences in postoperative CCD were detected between Arthroscopy and Miniopen groups (p > 0.05). Statistically significant differences in preoperative CCD were observed in both groups (n = 15) using weight-bearing/no weight-bearing AP views (P = 0.0009). Conclusion Stabilization of dislocated ACJ with dynamic systems is the method of choice providing excellent and good outcomes rated by UCLA rating scale, ASES shoulder score and CSS at long-term follow-up. One-stage surgical treatment is an advantage of dynamic systems with no need of construct removal. Standard and weighted stress radiographs of the involved side indicate to ACJ injury in comparison with contralateral side. Further research is needed for a longer term follow-up with the bone reduction maintained with dynamic system

Magnetic, electronic, and transport properties of the high-pressure-synthesized chiral magnets Mn1-xRhxGe

We report on the structural, magnetic, and transport properties of a set of high-pressure-synthesized compounds Mn1-xRhxGe (0≤x≤1) with chiral magnetic ordering. The magnetic and transport properties depend substantially on the concentration of rhodium (x) and the pressure. The saturation magnetic moment corresponds to a known high-spin value for pristine MnGe (x=0) and decreases almost linearly with increasing concentration x. In addition, x-ray magnetic circular dichroism spectra taken at 10 K and 2 T indicate magnetic polarization of the Rh 4d electron states and Ge 4p states, which decreases with x, too. In rhodium-rich compounds (x≥0.5), the temperature of the magnetic ordering increases significantly with pressure, whereas in manganese-rich compounds (x<0.5) the temperature decreases. Three different tendencies are also found for several structural and transport properties. In the intermediate range (0.3≤x≤0.7), samples are semiconducting in the paramagnetic phase, but they become metallic in the magnetically ordered state. We carried out ab initio density-functional calculations of Mn1-xRhxGe at various concentrations x and traced the evolution of the electronic and magnetic properties. The calculation results are in good agreement with the measured magnetic moments and qualitatively explain the observed trends in transport properties. © 2018 American Physical Society

Эффективность и безопасность биоаналогичного лекарственного препарата Тигераза® (дорназа альфа) при длительной симптоматической терапии пациентов с муковисцидозом: результаты клинического исследования III фазы

The article discusses the results of a phase III clinical trial to compare the pharmacokinetics, efficacy and safety of the biosimilar medicinal product Tigerase® (dornase alpha) (Generium JSC, Russia) and the reference medicinal product Pulmozyme® (F.Hoffmann-La Roche Ltd, Switzerland) with the purpose of establishing their comparability for symptomatic treatment of patients with cystic fibrosis (CF).Methods. The study included 100 patients aged 18 years and older with a confirmed diagnosis of CF, who were divided into two groups by stratified randomization in a ratio of 1 : 1 based on the initial level of FEV1 (40–60% or &gt; 60–100% from due value). Tigerase® or Pulmozyme® were used in a dose of 2.5 mg daily, once a day in the form of inhalations using a jet nebulizer compressor for 24 weeks.Results and discussion: The analysis of the data regarding the primary efficacy endpoint – changes in FEV1 – showed that in both groups (FAS population (Full analyses set) and PP population (Per protocol)), similar changes in FEV1 were observed. The average value of changes in FEV1 after 24 weeks of treatment compared with the initial level in the FAS population was –1.3% ± 9.8 % (95% CI (–4.1; 1.6)) in Group I (Tigerase®) and –1.9% ± 10.0% (95% CI (–4.7; 1.0)) in Group II (Pulmozyme®). The point estimate for the intergroup difference in changes in FEV1 (Group I – Group II) was 0.6%. The calculated 95% CI for the difference in changes in FEV1 in the FAS population was (–3.3; 4.6%]. In both populations studied, the intergroup difference in changes in FEV1 did not exceed 6%. During long-term treatment of patients with CF, no statistically significant differences were found in terms of efficacy (changes in FEV1 and FVC; number of exacerbations of chronic pulmonary disease and the number of days before its development; change in body weight; quality of life) between medicinal products in both studied populations (FAS and PP).Conciusion. A safety analysis demonstrated the comparability of medicinal products in terms of the incidence of adverse events. The frequency of detection of antibodies to dornase alpha during the study was similar in the treatment groups; the formation of antibodies did not lead to a decrease in the efficacy and safety of therapy.В статье рассматриваются результаты сравнительного клинического исследования III фазы по изучению фармакокинетики, эффективности и безопасности биоаналогичного препарата Тигераза® (дорназа альфа) (АО «Генериум», Россия) и референтного препарата Пульмозим® (Ф.Хоффманн-Ля Рош Лтд., Швейцария) с целью установления их сопоставимости для симптоматической терапии пациентов с муковисцидозом (МВ).Материалы и методы. В исследование включены пациенты (n = 100) в возрасте 18 лет и старше с подтвержденным диагнозом МВ, которые методом стратифицированной рандомизации были распределены на 2 группы в соотношении 1 : 1 по исходному уровню объема форсированного выдоха за 1-ю секунду (ОФВ1) 40–60 или &gt; 60–100%долж. Указанные препараты применялись в дозе 2,5 мг ежедневно 1 раз в сутки в виде ингаляций с помощью джет-небулайзера-компрессора в течение 24 нед.Результаты. По результатам анализа данных первичной конечной точки эффективности, изменения ОФВ1 показано, что у пациентов обеих групп лечения в популяции полного набора данных для анализа (включая данные всех рандомизированных пациентов) (Full analyses set – FAS) и популяции в соответствии с протоколом (все рандомизированные пациенты, завершившие исследование без нарушений протокола) (Per protocol – PP) наблюдались схожие изменения показателей ОФВ1. Среднее значение изменения показателей ОФВ1 через 24 нед. терапии по сравнению с исходным уровнем в FAS-популяции составило –1,3 ± 9,8% (95%-ный доверительный интервал (ДИ) – (–4,1; 1,6)) в 1-й группе (Тигераза®) и –1,9 ± 10,0% (95%-ный ДИ – (–4,7; 1,0)) – во 2-й (Пульмозим®). Точечная оценка для межгрупповой разности изменения ОФВ1 (1-я – 2-я группы) составила 0,6%. Рассчитанный 95%-ный ДИ для разности изменения ОФВ1 в FAS-популяции составил –3,3; 4,6%. В обеих изучаемых популяциях межгрупповая разность по изменению ОФВ1 не превышала 6%. При длительной терапии пациентов с МВ статистически значимых отличий по показателям эффективности (изменение ОФВ1 и форсированной жизненной емкости легких; число обострений хронического бронхолегочного процесса и число дней до его развития; изменение массы тела; качество жизни пациентов) между указанными препаратами в обеих изучаемых популяциях (FAS и PP) не выявлено. По результатам анализа безопасности продемонстрирована сопоставимость исследуемого или референтного препаратов по частоте развития нежелательных явлений. Частота выявления антител к препарату дорназа альфа в ходе исследования в группах лечения была сходной; образование антител не приводило к снижению эффективности и безопасности терапии.Заключение. На основании результатов проведенного клинического исследования доказано, что препарат Тигераза® (АО «Генериум», Россия) является биологическим аналогом препарата Пульмозим® (Ф.Хоффманн-Ля Рош Лтд., Швейцария)

RECONSTRUCTION OF SOFT TISSUE OF HAND USING ISLAND AND PERFORATOR FLAPS

Objective: to determine the capabilities and perspectives of island and perforator flaps for soft tissue reconstruction of the hand. Material and methods. Results of treatment of 41 patients with defects of the soft tissue of the hand, treated at the in the period from 2010 to 2013 and operated using the island flaps and perforator flaps (DAP flap). Results and conclusion. In all cases the authors have received positive functional and cosmetic results, which were evaluated using a questionnaire DASH, the average score was 12.3. Digital artery perforator flaps allow close defect covering tissue any surface fingers. The use of perforator flaps allows reconstructing soft tissue defect with the skin of the same anatomical region as identical morphologically lost. The second important advantage is that the DAP flap is not included in the magisterial arteries, allows its use as a recipient for subsequent microsurgical reconstructions

CRUCIATE LIGAMENT RECONSTRUCTION

Purpose: To evaluate long-term results of meniscal repair during arthroscopic ACL reconstruction.Materials and methods: 45 patients who underwent meniscal repair during arthroscopic ACL reconstruction between 2007 and 2013 by the same surgeon were included in the study. In total, fifty meniscus were repaired (26 medial and 24 lateral). Procedures included use of one up to four Fast-Fix implants (Smith &amp; Nephew). In five cases both medial and lateral meniscus were repaired. Cincinnati, IKDC and Lysholm scales were used for long-term outcome analysis.Results: 19 male and 26 female patients were included in the study aging from 15 to 59 years (mean age 33,2±1,5). Median time from injury to surgical procedure was zero months (ranging zero to one). Mean time from surgery to scale analysis was 55,9±3 months (ranged 20-102). Median Cincinnati score was 97 (ranged 90-100), with excellent results in 93% of cases (43 patients) and good results in 7% (3 patients). Median IKDC score was 90,8 (ranged 86,2-95,4), with excellent outcomes in 51% of cases (23 patients), good in 33% (15 patients) and satisfactory in 16% (7 patients). Median Lysholm score was 95 (ranged 90-100), with excellent outcomes in 76% of cases (34 patients) and good in 24% (11 patients). Authors identified no statistical differences when comparing survey results in age, sex and time from trauma to surgery.Conclusions: Results of the present study match the data from orthopedic literature that prove meniscal repair as a safe and efficient procedure with good and excellent outcomes. All-inside meniscal repair can be used irrespectively of patients' age and is efficient even in case of delayed procedures

Infection after Arthroscopic Cuff Tear Repair (Case Report)

Septic shoulder arthritis following arthroscopic surgery is a rare complication, according to the literature it arises from 0.006% to 2,1% of cases. We report on a case of 58 y.o. Patient, admitted to our setting 10 days after arthroscopic intervention on the right shoulder joint in another hospital. Based on clinical, laboratory and instrumental assessment septic shoulder arthritis was diagnosed. Arthroscopic lavage and debridement surgery with bioabsorbable antibacterial agent implantation was performed. Long term follow-up in 6 months showed good results with full range of motion, absence of pain and elimination of infection