345 research outputs found
Mineral and bone metabolism in patients with idiopathic scoliosis depending on the magnitude of the deformity
Objective: Analysis of the results of the study of mineral metabolism and bone formation markers in patients with idiopathic scoliosis, depending on the magnitude of the deformity.Material and methods: Based on the retrospective single‑center study in 30 patients diagnosed with scoliosis the preoperative parameters of calcium metabolism (total and ionized calcium, parathyroid hormone, 24‑hour urine calcium), phosphorus, bone formation markers (alkaline phosphatase, osteocalcin, P1NP in the blood), deoxypyridinoline in morning urine, blood levels of 25(OH)D have been analyzed. The patients were divided into 3 groups: with a deformity of 25–40 ° (group 1), 40–60 ° (group 2) and 60–80 ° (group 3) (n = 30). The mean age in all groups was 18.5 ± 4.7.Results: In patients with idiopathic scoliosis, alkaline phosphatase and P1NP significantly exceeded normal values in the first group, which indicated a more high‑turnover type of bone remodeling with a deficient level of 25(OH)D. A higher excretion of deoxypyridinoline and a decrease in phosphorus in blood in patients with a deformity of 60–80 ° suggest a violation of the ratio of the processes of synthesis and resorption in bone tissue.Conclusion: The study of mineral metabolism and all the main markers of bone formation made it possible to obtain a more complete picture of the state of metabolic processes in bone tissue, to obtain reliable data on the effect of some of them on the nature of bone remodeling and the magnitude of spinal deformity
Radiomorphological Parameters of the Foot Bones During the Talus Fracture Treatment Using the Ilizarov Apparatus
Background: Talus fractures are one of the most dangerous injuries leading to serious consequences. Quite a lot of treatment methods have been proposed, but the use of the Ilizarov apparatus is relatively rare. Objective: To justify the use of the Ilizarov apparatus in the talus fracture treatment by studying radiomorphological parameters of the foot bones at different stages of follow-up. Methods: We used radiography and multislice computed tomography (MSCT) in 25 patients treated for talus injuries by the Ilizarov apparatus to study radiographic and radiomorphological features of the foot bones at different stages of follow-up. We analyzed normal parameters of the foot bones forming the ankle joint in 15 patients. Results and discussion: Dynamics of talus radiomorphology during its fracture or fracture-dislocation are characterized by a gradual increase in the bone density at the union site. The local density of the talus at the fracture site gradually increased and exceeded 500 HU in 6 months. The organotypic adjustment at the union site did not end by this time, given the architecture of the talus and the biomechanics of the foot. We observed a decrease in the total densities of the talus and calcaneus during fixation by the Ilizarov apparatus and their gradual return to normal values after removal of the apparatus. Conclusions: Talus fracture treatment by transosseous osteosynthesis using the Ilizarov apparatus makes it possible to get immediate good results, especially using a configuration with hinges allowing for early mobilization of the ankle joint and loading in the early stages of treatment
СОВРЕМЕННЫЕ МЕТОДЫ ИЗУЧЕНИЯ ДИСТРАКЦИОННОГО РЕГЕНЕРАТА С ПРИМЕНЕНИЕМ ЛУЧЕВОЙ ДИАГНОСТИКИ
The review presents the results of diagnostic imaging techniques for evaluation of distractional regenerate bone starting from classical polypositional radiography to modern imaging modalities such as magnetic resonance imaging and computed tomography. There are described the modifications of the known techniques for evaluation of regeneration bone with quantitative and qualitative analysis, the opinions of different authors about possibilities and problems of imaging practices. There are presented the problems and goals for more effective evaluation of new bone at different stages of limb lengthening with the focus on a wider application of modern imaging modalities at medical institutions. The review is based on dissertation work of K. A. Diachkov «Diagnostic imaging for detection of the rules of distractional regenerate bone formation and bone quality during limb lengthening». Literature review was performed using database of PubMed, Medline, Embase 12 Russian journals on traumatology and orthopaedics, diagnostic imaging 2007–2016. All articles on evaluation of distractional bone regeneration were reviewed.В представленном обзоре представлены данные о применении методов лучевой диагностики для изучения дистракционного регенерата, начиная с классической полипозиционной рентгенографии и заканчивая самыми современными методами визуализации, в том числе магнитно-резонансной и компьютерной томографии. Приведены данные о различных модификациях известных методик, проанализированы способы оценки регенерата при изучении его качественных и количественных показателей, рекомендации и мнения авторов о возможности и проблемах использованных методик. Указано на нерешенные вопросы и задачи для более эффективного исследования новообразованной кости в различные периоды удлинения конечности, на необходимость более широкого внедрения современной аппаратуры в лечебных учреждениях. Материал, использованный для подготовки обзора, взят из диссертации К. А. Дьячкова «Лучевая диагностика в выявлении закономерностей формирования дистракционного регенерата и качества кости при удлинении конечности», защищенной 15 февраля 2017 г. по специальности 14.01.13 «Лучевая диагностика, лучевая терапия» в диссертационном совете Д208.041.04 на базе ГБОУ ВО МГМСУ им. А. И. Евдокимова Минздрава России, научный консультант — заслуженный деятель науки Российской Федерации, доктор медицинских наук, профессор, член-корреспондент РАН Васильев Александр Юрьевич. Обзор литературы проведен на основании анализа данных базы РubMed, Medline, Embase 12 русскоязычных журналов по травматологии и ортопедии, лучевой диагностике. Рассматривались статьи за 2007–2016 гг. Анализировались все статьи, где рассматривались вопросы изучения дистракционного регенерата методами лучевой диагностики
Biochemical blood parameters in determining the elastic properties of the vascular wall in hypertensive patients with abdominal obesity
The article describes approaches that use parameters of biochemical laboratory markers as the basis for the indirect determination of the value of a functional parameter 'pulse wave velocity*, which characterizes the stiffness of the vessel wall. Using a mathematical model of an artificial neural network makes it possible to assess the degree of deviation of the resulting stiffness of the vessel wall from the standard value. An increase in this value is determined by the defeat of the vascular wall as a target organ that helps to clarify the stage of hypertension and optimize antihypertensive therapy in hypertensive patients with abdominal obesity.В статье описаны подходы, позволяющие использовать параметры биохимических лаб раторных маркеров в качестве основы для оценки величины функционального параметра «скорость распространения пульсовой волны», характеризующего жесткость сосудистой стенки. Использование математической модели искусственной нейронной сети дает возможность оценить степень отклонения полученного показателя жесткости сосудистой стенки от нормативного значения. При повышении этого значения определяется поражение сосудистой стенки как органа-мишени, что позволяет уточнить стадию артериальной гипертонии и провести оптимизацию антигипертензивной терапии у больных артериальной гипертонией с абдоминальным ожирением
Studies of and production in and Pb collisions
The production of and mesons is studied in proton-proton and
proton-lead collisions collected with the LHCb detector. Proton-proton
collisions are studied at center-of-mass energies of and ,
and proton-lead collisions are studied at a center-of-mass energy per nucleon
of . The studies are performed in center-of-mass rapidity
regions (forward rapidity) and
(backward rapidity) defined relative to the proton beam direction. The
and production cross sections are measured differentially as a function
of transverse momentum for and , respectively. The differential cross sections are used to
calculate nuclear modification factors. The nuclear modification factors for
and mesons agree at both forward and backward rapidity, showing
no significant evidence of mass dependence. The differential cross sections of
mesons are also used to calculate cross section ratios,
which show evidence of a deviation from the world average. These studies offer
new constraints on mass-dependent nuclear effects in heavy-ion collisions, as
well as and meson fragmentation.Comment: All figures and tables, along with machine-readable versions and any
supplementary material and additional information, are available at
https://lhcbproject.web.cern.ch/Publications/p/LHCb-PAPER-2023-030.html (LHCb
public pages
Fraction of decays in prompt production measured in pPb collisions at TeV
The fraction of and decays in the prompt
yield, , is measured by
the LHCb detector in pPb collisions at TeV. The study
covers the forward () and backward () rapidity
regions, where is the rapidity in the nucleon-nucleon
center-of-mass system. Forward and backward rapidity samples correspond to
integrated luminosities of 13.6 0.3 nb and 20.8 0.5
nb, respectively. The result is presented as a function of the
transverse momentum in the range 1 GeV/.
The fraction at forward rapidity is compatible with the LHCb
measurement performed in collisions at TeV, whereas the
result at backward rapidity is 2.4 larger than in the forward region
for GeV/. The increase of at low at backward rapidity is compatible with the suppression of the
(2S) contribution to the prompt yield. The lack of in-medium
dissociation of states observed in this study sets an upper limit of
180 MeV on the free energy available in these pPb collisions to dissociate or
inhibit charmonium state formation.Comment: All figures and tables, along with machine-readable versions and any
supplementary material and additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-028.html (LHCb
public pages
Observation of Cabibbo-suppressed two-body hadronic decays and precision mass measurement of the baryon
The first observation of the singly Cabibbo-suppressed
and decays
is reported, using proton-proton collision data at a centre-of-mass energy of
, corresponding to an integrated luminosity of , collected with the LHCb detector between 2016 and 2018. The
branching fraction ratios are measured to be
,
. In addition, using the
decay channel, the baryon
mass is measured to be , improving the
precision of the previous world average by a factor of four.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-011.html (LHCb
public pages
Enhanced production of baryons in high-multiplicity collisions at TeV
The production rate of baryons relative to mesons
in collisions at a center-of-mass energy TeV is measured
by the LHCb experiment. The ratio of to production
cross-sections shows a significant dependence on both the transverse momentum
and the measured charged-particle multiplicity. At low multiplicity, the ratio
measured at LHCb is consistent with the value measured in
collisions, and increases by a factor of with increasing multiplicity.
At relatively low transverse momentum, the ratio of to
cross-sections is higher than what is measured in
collisions, but converges with the ratio as the momentum
increases. These results imply that the evolution of heavy quarks into
final-state hadrons is influenced by the density of the hadronic environment
produced in the collision. Comparisons with a statistical hadronization model
and implications for the mechanisms enforcing quark confinement are discussed.Comment: All figures and tables, along with machine-readable versions and any
supplementary material and additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-027.html (LHCb
public pages
Measurement of lepton universality parameters in and decays
A simultaneous analysis of the and decays is performed to test muon-electron universality in
two ranges of the square of the dilepton invariant mass, . The measurement
uses a sample of beauty meson decays produced in proton-proton collisions
collected with the LHCb detector between 2011 and 2018, corresponding to an
integrated luminosity of . A sequence of multivariate
selections and strict particle identification requirements produce a higher
signal purity and a better statistical sensitivity per unit luminosity than
previous LHCb lepton universality tests using the same decay modes. Residual
backgrounds due to misidentified hadronic decays are studied using data and
included in the fit model. Each of the four lepton universality measurements
reported is either the first in the given interval or supersedes previous
LHCb measurements. The results are compatible with the predictions of the
Standard Model.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-045.html (LHCb
public pages
A measurement of
Using a dataset corresponding to of integrated
luminosity collected with the LHCb detector between 2011 and 2018 in
proton-proton collisions, the decay-time distributions of the decay modes
and
are studied. The decay-width difference between the light and heavy mass
eigenstates of the meson is measured to be , where the first uncertainty is
statistical and the second systematic.Comment: All figures and tables, along with machine-readable versions and any
supplementary material and additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2023-025.htm
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