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1.
Sci Rep ; 14(1): 11378, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762557

RESUMO

We report a study of the entanglement between the quantized photon field and an atom arising in the photo-ionization process. Our approach is based on an ab initio solution of the time-dependent Schrödinger equation (TDSE) describing the quantum evolution of a bipartite system consisting of the atom and the quantized electromagnetic field. Using the solution of the TDSE, we calculate the reduced photon density matrix, which we subsequently use to compute entanglement entropy. We explain some properties of the entanglement entropy and propose an approximate formula for the entanglement entropy based on the analysis of the density matrix and its eigenvalues. We present the results of a comparative study of the entanglement in the photo-ionization process for various ionization regimes, including the tunneling and the multiphoton ionization regimes.

2.
Microbiome ; 12(1): 74, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622632

RESUMO

BACKGROUND: The equine gastrointestinal (GI) microbiome has been described in the context of various diseases. The observed changes, however, have not been linked to host function and therefore it remains unclear how specific changes in the microbiome alter cellular and molecular pathways within the GI tract. Further, non-invasive techniques to examine the host gene expression profile of the GI mucosa have been described in horses but not evaluated in response to interventions. Therefore, the objectives of our study were to (1) profile gene expression and metabolomic changes in an equine model of non-steroidal anti-inflammatory drug (NSAID)-induced intestinal inflammation and (2) apply computational data integration methods to examine host-microbiota interactions. METHODS: Twenty horses were randomly assigned to 1 of 2 groups (n = 10): control (placebo paste) or NSAID (phenylbutazone 4.4 mg/kg orally once daily for 9 days). Fecal samples were collected on days 0 and 10 and analyzed with respect to microbiota (16S rDNA gene sequencing), metabolomic (untargeted metabolites), and host exfoliated cell transcriptomic (exfoliome) changes. Data were analyzed and integrated using a variety of computational techniques, and underlying regulatory mechanisms were inferred from features that were commonly identified by all computational approaches. RESULTS: Phenylbutazone induced alterations in the microbiota, metabolome, and host transcriptome. Data integration identified correlation of specific bacterial genera with expression of several genes and metabolites that were linked to oxidative stress. Concomitant microbiota and metabolite changes resulted in the initiation of endoplasmic reticulum stress and unfolded protein response within the intestinal mucosa. CONCLUSIONS: Results of integrative analysis identified an important role for oxidative stress, and subsequent cell signaling responses, in a large animal model of GI inflammation. The computational approaches for combining non-invasive platforms for unbiased assessment of host GI responses (e.g., exfoliomics) with metabolomic and microbiota changes have broad application for the field of gastroenterology. Video Abstract.


Assuntos
Microbiota , Animais , Cavalos/genética , Mucosa Intestinal/metabolismo , Metaboloma , Fezes/microbiologia , Anti-Inflamatórios não Esteroides/metabolismo , Inflamação/metabolismo , Fenilbutazona/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
3.
Heliyon ; 10(7): e29258, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38623185

RESUMO

Introduction: Endemic human coronaviruses (eHCoVs) are found worldwide and usually result in mild to moderate upper respiratory tract infections. They can lead to more severe illnesses such as croup, bronchiolitis, and pneumonia in vulnerable populations. During the coronavirus disease 2019 (COVID-19) pandemic, information on HCoV prevalence and incidence and clinical impact of co-infections of HCoV with SARS-CoV-2 was lacking. Objectives: Thus, this study aimed to determine the prevalence and clinical significance of infections caused by eHCoVs during the COVID-19 pandemic in Bulgaria. Methods: From January 2021 to December 2022, nasopharyngeal swabs of patients with acute upper or lower respiratory tract infections were tested for 17 respiratory viruses using multiplex real-time polymerase chain reaction assays. The clinical data and laboratory parameters of patients infected with respiratory viruses were analysed. Results: Of the 1375 patients screened, 24 (1.7 %) were positive for HCoVs, and 197 (14.3 %) were positive for eight other seasonal respiratory viruses. Five (0.7 %) of 740 patients positive for SARS-CoV-2 were co-infected with eHCoVs. Co-infected patients had a mean C-reactive protein level of 198.5 ± 2.12 mg/mL and a mean oxygen saturation of 82 ± 2.8 mmHg, while those in patients co-infected with SARS-CoV-2 and other respiratory viruses were 61.8 mg/mL and 92.8 ± 4.6 mmHg, respectively (p < 0.05). Pneumonia was diagnosed in 63.3 % of patients with HCoV infection and 6 % of patients positive for other seasonal respiratory viruses (p < 0.05). Patients with SARS-CoV-2 mono-infection stayed in hospital for an average of 5.8 ± 3.7 days, whereas the average hospital stay of patients with eHCoV and SARS-CoV-2 co-infection was 9 ± 1.4 days (p < 0.05). Conclusion: These findings indicate the low prevalence of eHCoVs and low co-infection rate between eHCoVs and SARS-CoV-2 during the COVID-19 pandemic in Bulgaria. Despite their low incidence, such mixed infections can cause severe signs that require oxygen therapy and longer hospital stays, underlining the need for targeted testing of severe COVID-19 cases to identify potential co-infections.

4.
Biomed Khim ; 70(1): 15-24, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38450677

RESUMO

Using the model of cyclophosphamide (CP)-induced immunosuppression in C57BL/6 mice, the hepatotropic effects of a conjugate of betulonic acid with 9-(4-methylpiperazin-1-ylmethyl)-2-(1,2,3-triazolyl) oreozelone (BABC) have been studied. In the liver of treated animals the expression of genes for cytochromes (CYP 1A1, CYP 1A2, CYP 3A44, CYP 2B10, CYP 2C29, CYP 17A1), PPARA, and cytokines (TNF-α, IL-1ß, IL-12α, IL-10) and the relative levels of NF-κB p65, GST-π, and NAT-1 proteins were determined. On day six after administration of the compound and CP to animals a significant (3.2-fold) increase in the expression of the CYP 2B10 as compared to the control group was observed. Treatment of mice with the compound and CP also caused a 2.4-fold increase in the mRNA level of the pro-inflammatory TNF-α gene as compared to the group of animals receiving CP. Administration of the studied compound to intact animals was accompanied by a 2.5-fold increase in the IL-1ß expression and a 1.8-fold decrease in the IL-10 expression as compared to the control group. An increase in the expression of pro-inflammatory cytokine genes in the liver of animals treated with the compound was accompanied by an increase in the content of NF-κB p65 (by 1.6 times), as well as an increase in the relative amount of NAT-1 protein (by 2.7 times) as compared to control animals.


Assuntos
Ácido Betulínico , Ácido Oleanólico , Fator de Necrose Tumoral alfa , Animais , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/genética , Interleucina-10 , NF-kappa B , Ciclofosfamida
5.
Biomed Khim ; 69(4): 219-227, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37705482

RESUMO

The immunomodulatory activity of a betulonic acid-based compound with furocoumarin (BABCF; 2-azido, 9-N-methylpiperazinomethyl oreozelone) has been investigated. Male C57BL/6 mice (aged 3 months) treated with the cytostatic agent cyclophosphamide (CP) and intact individuals served as experimental models. The expression of genes was studied in bone marrow (IL-12, IL-10, IL-1ß, TNF-α, TGF-ß, M-CSF, GM-CSF) or in the suspension of peritoneal cells (IL-12, IL-10; as the injection site). The surface markers of T-lymphocytes (CD3, CD4, and CD8) in fractions of venous blood mononuclear cells (MNCs) were determined by means of flow cytometry using antibodies. Histological and morphometric studies were performed to assess the impact of CP and BABCF on the thymus. BABCF caused a pronounced (about 3-fold) increase in relative expression of the GM-KSF gene. BABCF caused a local increase in the expression of IL-12 in the peritoneal cavity cells and restored the relative content of T-lymphocytes in the blood of CP-treated mice treated affecting mainly CD3⁺CD4⁺ lymphocytes. This substance reduced the tissue density of the thymic cortex and thymic medulla in CP-treated mice. Thus, results of this study suggest that BABCF exhibits a stimulating effect on the cellular link of immunity and promotes maintenance of the number of T-lymphocytes in the blood due to their migration from the central organs of the immune system.


Assuntos
Interleucina-10 , Fator de Necrose Tumoral alfa , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Anticorpos , Ciclofosfamida
6.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37325830

RESUMO

Modern warfare is characterized by common mine-explosive injuries. The last ones are accompanied by multiple injuries, large area of damage and severe clinical status of victims. OBJECTIVE: To demonstrate treatment of mine-explosive spinal injuries using modern minimally invasive endoscopic techniques. MATERIAL AND METHODS: The authors present 3 victims with various mine-explosive injuries. Endoscopic removal of fragments from the lumbar and cervical spine was successful in all cases. DISCUSSION: Most of victims with injuries of the spine and spinal cord do not require urgent surgery and can underwent surgical treatment after clinical stabilization. At the same time, minimally invasive techniques provide surgical treatment with minimal risk and earlier rehabilitation, as well as reduce the risk of infectious complications associated with foreign bodies. CONCLUSION: Careful selection of patients for spinal video endoscopy will ensure positive outcomes. Minimization of iatrogenic postoperative injuries is especially important in patients with combined trauma. However, well-experienced surgeons should perform these procedures at the stage of specialized medical care.


Assuntos
Traumatismos da Coluna Vertebral , Humanos , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Traumatismos da Coluna Vertebral/cirurgia , Endoscopia/efeitos adversos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia
7.
Artigo em Russo | MEDLINE | ID: mdl-36541319

RESUMO

The article considers possible risks according analysis of comprehension by workers of necessary competencies ensuring quality and safety of medical activities at performing their duties as well as assessment of factors affecting completeness of choice. It is proposed to apply corporate training as component targeted to improving quality and safety of medical activities by addressed training of necessary competencies within the framework of continuous medical education, supplementing existing self-education.


Assuntos
Pessoal de Saúde , Competência Profissional , Humanos , Competência Clínica , Currículo , Educação Médica Continuada
8.
Sci Rep ; 12(1): 19533, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376546

RESUMO

We describe an approach to the description of the time-development of the process of strong field ionization of atoms based on the calculation of the joint probability of occurrence of two events, event B being finding atom in the ionized state after the end of the laser pulse, event A being finding a particular value of a given physical observable at a moment of time inside the laser pulse duration. As an example of such an physical observable we consider lateral velocity component of the electron's velocity. Our approach allows us to study time-evolution of the lateral velocity distribution for the ionized electron during the interval of the laser pulse duration. We present results of such a study for the cases of target atomic systems with short range Yukawa and Coulomb interactions.

9.
Artigo em Russo | MEDLINE | ID: mdl-36282661

RESUMO

Currently, more and more attention is paid to the shortage of medical staff in rural and remote areas. In order to ensure the staffing of medical institutions with workers in rural areas, in the regions one-time compensations are paid as part of an event called "Zemsky Doctor". However, "Zemsky Doctor" has shown a fading effect over the years of implementation, including due to the unwillingness of medical students to participate in this program. The purpose of the work is to identify the attitude of students of medical universities to participation in the "Zemsky Doctor" program and develop measures to increase the attractiveness of the program. To achieve the goal of the study, we conducted a survey of 250 medical students from all over Russia, interviews with medical students, with medical staff, including former and current participants. The novelty of the work lies in the study of the attitude of current and potential participants in the program in order to develop proposals for its improvement. To improve the program, it is necessary to choose the term for concluding the contract, differentiate payments depending on the distance from the regional center, create an information site, defer the army for the duration of the contract.


Assuntos
Serviços de Saúde Rural , Estudantes de Medicina , Humanos , Recursos Humanos , População Rural , Inquéritos e Questionários , Escolha da Profissão
10.
Sci Rep ; 12(1): 17048, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36221023

RESUMO

We combine IR pump and XUV probe laser pulses to visualize the Kramers-Henneberger (KH) state of the potassium atom. We demonstrate that ionization of such an atom exhibits some molecular-like features such as low order interference maxima in photoelectron momentum spectra. The locations of these maxima allow to estimate spatial dimensions of the KH atom and can be used for accurate calibration of high intensity laser fields. At the same time, we show that an analogy between the KH atom and a homo-nuclear diatomic molecule cannot be extended too far. In particular, higher order interference maxima are very difficult to observe in the case of the KH state. We attribute this to a particular structure of the KH potential which does not confine electron motion to a well-defined potential well unlike in real diatomic molecules.

11.
Opt Express ; 30(16): 28686-28695, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36299058

RESUMO

The superposition of a fundamental laser pulse and its second harmonic can form an asymmetric laser field that is useful in many applications. The temporal characterization of the two-color laser field becomes necessary. However, the temporal characterization of the two-color laser pulse is a challenging task due to its broad bandwidth and a spectral gap between the two frequency components. Here we demonstrate the temporal characterization of the two-color laser field using multiple ionization yield measurements near the laser focus. This new approach enables the complete temporal characterization of the two-color laser field, including the relative phase between the two frequency components.

12.
Ter Arkh ; 94(8): 1028-1035, 2022 Oct 12.
Artigo em Russo | MEDLINE | ID: mdl-36286985

RESUMO

The Advisory Board chaired by the chief specialist in infectious diseases of the Ministry of Health of Russian Federation, Professor V.P. Chulanov was held on June 18, 2022 in Saint Petersburg. Aim. The main purpose of the Board was following discussion: the analysis of the real-world data of levilimab as an anticipatory therapy for COVID-19 in hospitalized patients; the review of the experience and perspectives of levilimab as an anticipatory anti-inflammatory option for outpatient patients who meet defined clinical and laboratory criteria. Results. The analyzed data on clinical efficacy and safety formed the basis of recommendations proposed by experts for the use of levilimab in the inpatient and outpatient medical care for COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anti-Inflamatórios , Receptores de Interleucina-6
13.
J Control Release ; 349: 475-485, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35839934

RESUMO

Bismuth-based compounds are considered to be the best candidates for computed tomography (CT) imaging of gastrointestinal (GI) tract due to high X-ray absorption. Here, we report the introduction of polymer-coated bismuth oxychloride (BiOCl) nanosheets for highly efficient CT imaging in healthy mice and animal with colitis. We demonstrate simple, low cost and fast aqueous synthesis protocol which provides gram-quantity yield of chemically stable BiOCl nanosheets. The developed contrast gives 2.55-fold better CT enhancement compared to conventional contrast with negligible in vivo toxicity. As a major finding we report a regioselective CT imaging of GI tract by using nanoparticles coated with differentially charged polymers. Coating of nanoparticles with a positively charged polymer leads to their fast accumulation in small intestine, while the coating with negatively charged polymers stimulates prolonged stomach retention. We propose that this effect may be explained by a pH-controlled aggregation of nanoparticles in stomach. This feature may become the basis for advancement in clinical diagnosis of entire GI tract.


Assuntos
Bismuto , Polímeros , Animais , Bismuto/química , Trato Gastrointestinal/diagnóstico por imagem , Camundongos , Raios X
14.
Dokl Biochem Biophys ; 503(1): 47-51, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35538277

RESUMO

The data available to date indicate that the activation of nicotinic acetylcholine receptors (nAChR) of α7 type can reduce heart damage resulting from ischemia and subsequent reperfusion. We have studied two new synthetic D-analogs of 6-bromohypaphorine, which are selective agonists of α7 nAChR, in a rat model of myocardial ischemia. Acute myocardial infarction in animals was induced by occlusion of the left coronary artery with its subsequent reperfusion under mechanical lung ventilation. It was found that one of the analogs was more active, and treatment with it at the onset of reperfusion statistically reduced infarct size. This analog also prevented changes in the concentration of potassium and sodium ions in the blood, occurring during occlusion/reperfusion injury. The data obtained indicate that hypaphorine analogs are promising for the development of drugs that reduce the adverse effects of myocardial infarction.


Assuntos
Traumatismos Cardíacos , Infarto do Miocárdio , Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , Receptores Nicotínicos , Animais , Infarto do Miocárdio/tratamento farmacológico , Isquemia Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Ratos , Reperfusão , Triptofano/análogos & derivados
15.
Sud Med Ekspert ; 65(2): 59-64, 2022.
Artigo em Russo | MEDLINE | ID: mdl-35416020

RESUMO

The formation of non-traumatic intramuscular hemorrhages does not depend on the cause of death. They usually occur in the muscles attached to the rib cage, which are or may be involved in the inhalation process (84.6%). More often, non-respiratory muscles are damaged (66%), less often auxiliary respiratory muscles (15.5%), extremely rarely - the main respiratory muscles (3.3%). In hypothermia, the majority of hemorrhages are formed in the iliopsoas muscles (13.9%). The main reason for the appearance of hemorrhages is muscle overstrain in the agonal period due to increased respiratory activity and seizures. The motor activity of the upper extremities during drowning, prolonged static muscle tension during hypothermia may matter. A microscopic picture usually indicates the formation of hemorrhages shortly before death, and occasionally signs of anxiety are noted.


Assuntos
Afogamento , Hipotermia , Afogamento/diagnóstico , Patologia Legal , Hemorragia/etiologia , Humanos , Hipotermia/etiologia , Músculo Esquelético
16.
Sci Rep ; 11(1): 21457, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728673

RESUMO

We study propagation effects due to the finite speed of light in ionization of extended molecular systems. We present a general quantitative theory of these effects and show under which conditions such effects should appear. The finite speed of light propagation effects are encoded in the non-dipole terms of the time-dependent Shrödinger equation and display themselves in the photoelectron momentum distribution projected on the molecular axis. Our numerical modeling for the [Formula: see text] molecular ion and the [Formula: see text] dimer shows that the finite light propagation time from one atomic center to another can be accurately determined in a table top laser experiment which is much more readily accessible than the ground breaking synchrotron measurement by Grundmann et al. (Science 370:339, 2020).

17.
Sci Rep ; 11(1): 3956, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597606

RESUMO

We describe a procedure that allows us to solve the three-dimensional time-dependent Schrödinger equation for an atom interacting with a quantized one-mode electromagnetic field. Atom-field interaction is treated in an ab initio way prescribed by quantum electrodynamics. We use the procedure to calculate probability distributions of absorbed photons in the regime of tunneling ionization. We analyze evolution of the reduced photon density matrix describing the state of the field. We show that non-diagonal density matrix elements decay quickly, as a result of the decoherence process. A stochastic model, viewing ionization as a Markovian birth-death process, reproduces the main features of the calculated photon distributions.

18.
Drug Dev Ind Pharm ; 47(11): 1764-1774, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35322727

RESUMO

Branched oligohexamethyleneguanidine hydrochloride (branched OHMG-HC) possesses high biocidal activity. This study aimed at evaluating the pharmacokinetics of branched OHMG-HC and is mandatory for obtaining permission to conduct clinical studies. The thermal activation method was used to obtain radioactive-labeled drugs for the investigation of substance distribution in various tissues of experimental animals (rats and rabbits). Substance administration was carried out both orally (a dose was split into two equal volumes that were applied to buccal zones of the oral cavities of the animals) and intravenously to get a clear pharmacokinetic profile. In this research, the drug was applied in the concentration of 0.77 mg/kg with the addition of 0.037 mg/kg 3H-OHMG for rats, and 0.42 mg/kg with the addition of 0.015 mg/kg 3H-OHMG for Chinchilla rabbits. The selected samples of blood, organs, and urine underwent alkaline mineralization. A quantitative determination of 3H-OHMG was carried out using a liquid ß-, γ-counter according to the level of scintillation in the sample. Branched OHMG-HC displayed uniform distribution within all main organs and tissues upon oral administration. The highest concentrations were found in liver and kidney tissues, whereas the lowest in blood, cardiac muscle tissue, and brain. The closeness of the fabs values obtained from different animals (24.5% for rats and 29.0% for rabbits) demonstrated the absence of the species specificity in response to the pharmaceutical substance. The main parameters of excretion were established, and the half-life time was estimated to be 15 h.


Assuntos
Gengivite , Estomatite , Administração Oral , Animais , Fígado , Coelhos , Ratos , Distribuição Tecidual
19.
Ter Arkh ; 92(6): 33-36, 2020 Jul 09.
Artigo em Russo | MEDLINE | ID: mdl-33346490

RESUMO

AIM: Determine whether bone mineral density (BMD) assessed by dual-energy x-ray absorptiometry can be used as predictor of increased risk of death in hemodialysis patients. MATERIALS AND METHODS: A prospective study was performed of 516 patients with chronic kidney disease treated with hemodialysis (men 265, women 251, mean age 44.811.4 years) who were observed for 5.73.2 years. Before inclusion in the study, in all patients was analyzed bone mineral density using dual-energy X-ray absorptiometry in three standard departments: lumbar vertebrae, proximal femur and distal forearm. The probability analysis of the outcome was carried out using the KaplanMeier method and Cox. RESULTS: During follow-up period 111 (21.5%) patients died, 50.5% from cardiovascular events. Survival analysis by KaplanMeier method allowed to prove the increased risk of death from cardiovascular pathology in hemodailysis patients with low bone mineral density of all evaluated areas. Step-by-step multivariate Cox regression analysis showed that the T score of the femur, showing the difference of BMD of the patient with normal value of BMD for young adult, had the greatest prognostic significance. CONCLUSION: Reduced bone mineral density in patients receiving hemodialysis is associated with an increased risk of death from cardiovascular disease. Dual energy x-ray absorptiometry can be used for assessment of this risk.


Assuntos
Doenças Cardiovasculares , Osteoporose , Absorciometria de Fóton , Adulto , Densidade Óssea , Doenças Cardiovasculares/diagnóstico por imagem , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Osteoporose/diagnóstico por imagem , Estudos Prospectivos , Diálise Renal , Adulto Jovem
20.
Artigo em Russo | MEDLINE | ID: mdl-32526128

RESUMO

The article presents definition of concepts of exporting medical services in foreign and Russian practice. It includes overview of the elements of strategy of developing export of medical services (within the framework of the National project "Health Care"). The article considers the need to develop marketing strategy, information exchange system and conditions ensuring compliance of medical services with high standards of quality and safety of medical activities at the national level. The perspective direction development of the quality and safety system in Russia during implementation of the Federal project "Development of export of medical services" through improving the efficiency of medical organizations and their accreditation is determined.


Assuntos
Atenção à Saúde , Qualidade da Assistência à Saúde , Humanos , Federação Russa
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