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1.
Bull Exp Biol Med ; 169(4): 535-538, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32910382

RESUMO

A novel chemiluminescent method was developed to evaluate ROS generation by platelets. This method allows measuring activities of NADPH oxidase (NOX2) and enzymes synthesizing secondary ROS (superoxide dismutase, catalase, etc.) in resting and ADP-activated platelets (inductor of platelet aggregation and ROS generation) using a small number of cells. The method was tested in the examination of patients with coronary heart disease. It was found that platelets from patients with coronary heart disease were characterized by NOX2 activation, while cell metabolism is tuned for a long-term intensive production of superoxide anion radical. The enzymes synthesizing secondary ROS were also activated, but cell metabolism could not maintain their enhanced activity for a long time.


Assuntos
Plaquetas/metabolismo , Catalase/metabolismo , Doença das Coronárias/metabolismo , NADPH Oxidase 2/metabolismo , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Acridinas/química , Difosfato de Adenosina/metabolismo , Difosfato de Adenosina/farmacologia , Bioensaio , Plaquetas/efeitos dos fármacos , Estudos de Casos e Controles , Doença das Coronárias/patologia , Expressão Gênica , Humanos , Medições Luminescentes/métodos , Luminol/química , Oxirredução , Agregação Plaquetária/efeitos dos fármacos
2.
Phys Rev Lett ; 115(6): 062501, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26296112

RESUMO

The atomic mass difference of (163)Ho and (163)Dy has been directly measured with the Penning-trap mass spectrometer SHIPTRAP applying the novel phase-imaging ion-cyclotron-resonance technique. Our measurement has solved the long-standing problem of large discrepancies in the Q value of the electron capture in (163)Ho determined by different techniques. Our measured mass difference shifts the current Q value of 2555(16) eV evaluated in the Atomic Mass Evaluation 2012 [G. Audi et al., Chin. Phys. C 36, 1157 (2012)] by more than 7σ to 2833(30(stat))(15(sys)) eV/c(2). With the new mass difference it will be possible, e.g., to reach in the first phase of the ECHo experiment a statistical sensitivity to the neutrino mass below 10 eV, which will reduce its present upper limit by more than an order of magnitude.

3.
Bull Exp Biol Med ; 159(4): 557-66, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26395628

RESUMO

We compared the structure and mechanical properties of scaffolds based on pure collagen, pure chitosan, and a mixture of these polymers. The role of the composition and structure of scaffolds in the maintenance of cell functions (proliferation, differentiation, and migration) was demonstrated in two experimental models: homogeneous tissue analogues (scaffold populated by fibroblasts) and complex skin equivalents (fibroblasts and keratinocytes). In contrast to collagen scaffolds, pure chitosan inhibited the growth of fibroblasts that did not form contacts with chitosan fibers, but formed specific cellular conglomerates, spheroids, and lose their ability to synthesize natural extracellular matrix. However, the use of chitosan as an additive stimulated proliferative activity of fibroblasts on collagen, which can be associated with improvement of mechanical properties of the collagen scaffolds. The effectiveness of chitosan as an additional cross-linking agent also manifested in its ability to improve significantly the resistance of collagen scaffolds to fibroblast contraction in comparison with glutaraldehyde treatment. Polymer scaffolds (without cells) accelerated complete healing of skin wounds in vivo irrespective of their composition healing, pure chitosan sponge being most effective. We concluded that the use of chitosan as the scaffold for skin equivalents populated with skin cells is impractical, whereas it can be an effective modifier of polymer scaffolds.


Assuntos
Quitosana/química , Alicerces Teciduais/química , Animais , Proliferação de Células , Forma Celular , Células Cultivadas , Meios de Cultura/química , Módulo de Elasticidade , Fibroblastos/fisiologia , Humanos , Queratinócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Engenharia Tecidual , Cicatrização
4.
Ter Arkh ; 86(9): 97-101, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25518513

RESUMO

AIM: To estimate the value of the dosing Valsalva-Weber test (VWT) in the diagnosis of autonomic disorders in patients with vasovagal syncope (VVS). SUBJECTS AND METHODS: The dosing VWT using a specialized Task Force Monitor unit ("CNSystem", Austria) with synchronous noninvasive ECG and blood pressure (BP) monitoring was carried out in 30 patients (mean age 32 ± 14 years) with VVS and 12 healthy individuals (31 ± 7 years). The analysis of the test results encompassed the visual assessment of BP change curves and heart rate in different test phases and the calculation of pressure indices, Valsalva coefficient, arterial baroreflex sensitivity, and other parameters (a total of 26). RESULTS: The abnormally changed form of the mean BP curve, which was characterized by that BP by the end of Phase II test failed to achieve the baseline level, was recorded in 10 (33%) patients with VVS and in none of the healthy individuals (p = 0.04). An individual analysis of the gender- and age-adjusted Valsalva coefficient revealed its reduction in 9 (30%) patients while this indicator was within the normal range in all the healthy individuals (p = 0.04). CONCLUSION: During the dosing VWT, the signs of sympathetic insufficiency (impaired adrenergic regulation of BP) are found in 33% of the patients with VVS and those of parasympathetic insufficiency (impaired vagus regulation of cardiochronotropic function) are in 30%.


Assuntos
Doenças do Sistema Nervoso Autônomo , Síncope Vasovagal , Manobra de Valsalva , Adulto , Sistema Nervoso Autônomo/fisiopatologia , Doenças do Sistema Nervoso Autônomo/complicações , Doenças do Sistema Nervoso Autônomo/diagnóstico , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Exame Físico/métodos , Síncope Vasovagal/etiologia , Síncope Vasovagal/fisiopatologia
5.
Phys Rev Lett ; 110(8): 082501, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23473137

RESUMO

A novel approach based on the projection of the Penning-trap ion motion onto a position-sensitive detector opens the door to very accurate mass measurements on the ppb level even for short-lived nuclides with half-lives well below a second. In addition to the accuracy boost, the new method provides a superior resolving power by which low-lying isomeric states with excitation energy on the 10-keV level can be easily separated from the ground state. A measurement of the mass difference of ^{130}Xe and ^{129}Xe has demonstrated the great potential of the new approach.

6.
Bull Exp Biol Med ; 156(1): 161-4, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24319716

RESUMO

For modulation of antitumor cytotoxic activity of mononuclear cells in vitro, autologous dendritic cells loaded with tumor lysate antigens were cultured with peripheral blood mononuclear cells from patients with epithelial ovarian cancer in the presence or absence of IL-12 and IL-18. The efficiency of modulation was evaluated by cytotoxic activity of mononuclear cells against autologous tumor cells, by the production of IFN-γ, IL-4, and by the count of perforin-containing lymphocytes. It was demonstrated that dendritic cells stimulated cytotoxic immune response in mononuclear cell culture. Maximum induction of cytotoxic activity of mononuclear cells was attained in case of dendritic cells combination with IL-12 and IL-18 (increased death of autologous tumor cells, accumulation of perforin-positive lymphocytes, enhanced production of IFN-γ).


Assuntos
Antígenos de Neoplasias/fisiologia , Citotoxicidade Imunológica , Células Dendríticas/imunologia , Leucócitos Mononucleares/imunologia , Neoplasias Epiteliais e Glandulares/imunologia , Neoplasias Ovarianas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/metabolismo , Antígeno B7-2/metabolismo , Carcinoma Epitelial do Ovário , Células Cultivadas , Técnicas de Cocultura , Endocitose , Feminino , Humanos , Imunoglobulinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , Perforina/metabolismo , Antígeno CD83
7.
Vestn Ross Akad Med Nauk ; (5): 58-62, 2012.
Artigo em Russo | MEDLINE | ID: mdl-22856170

RESUMO

Molecular factors of pathogenesis of the eosinophilic blood reaction under pulmonary tuberculosis are analyzed in the article. It has been established that the key cytokine providing the development of hemic eosinophilia in patients with pulmonary tuberculosis is IL-5. IL-5 plasma concentration turned out to be increased only in patients with eosinophilia. Increase of eotaxin was determined in patients with tuberculosis despite of the presense of eosinophilia. One-directional nature of the defined changes in eotaxin concentration might be explained by dual properties of this chemokine: on the one hand, eotaxin mediates long-term presence of eosinophils in blood; on the other hand, it initiates the process of adhesion of eosinophilic leucocytes to vascular endothelium with their further migration to the focus of granulomatous inflammation. The established increase in number of IL-5R-positive eosinophils presents one more mechanism which explains the basis of long-term presence of eosinophils in peripheral blood in patients with pulmonary tuberculosis.


Assuntos
Quimiocina CCL11/metabolismo , Eosinofilia , Eosinófilos/metabolismo , Interleucina-5/metabolismo , Tuberculose Pulmonar , Adulto , Fenômenos Fisiológicos Celulares , Eosinofilia/sangue , Eosinofilia/etiologia , Feminino , Humanos , Inflamação/sangue , Inflamação/etiologia , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Tempo , Tuberculoma/sangue , Tuberculoma/etiologia , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/fisiopatologia
8.
Phys Rev Lett ; 84(18): 4043-6, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10990606

RESUMO

The E815 (NuTeV) neutrino experiment has performed a search for a 33. 9 MeV/c(2) weakly interacting neutral particle produced in pion decay. Such a particle may be responsible for an anomaly in the timing distribution of neutrino interactions in the KARMEN experiment. E815 has searched for this particle's decays in an instrumented decay region; no evidence for this particle was found. The search is sensitive to pion branching ratios as low as 10(-13).

9.
Surg Neurol ; 53(5): 493-7; discussion 497, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10874150

RESUMO

BACKGROUND: Hemifacial spasm is usually caused by compression of the facial nerve by ipsilateral blood vessels. Compression of the facial nerve root exit zone by a contralateral tortuous vertebral artery is very rare. METHODS: This 68-year-old woman presented with left-sided hemifacial spasm and was found to have compression of the left facial nerve by the tortuous vertebrobasilar artery, as revealed by magnetic resonance imaging and magnetic resonance angiography. Retromastoid craniectomy demonstrated compression of the left facial nerve root exit zone by the distal portion of the right vertebral artery. The vertebrobasilar junction and both vertebral arteries were moved laterally from the facial nerve and a muscle implant was interposed between the brainstem and the right vertebral artery. RESULTS: The patient has remained free of hemifacial spasm for a follow-up period of 27 months. CONCLUSIONS: Compression of the facial nerve by the contralateral tortuous vertebral artery may produce hemifacial spasm. A transposed large vessel can be secured by a sling technique or by interposing a soft implant between the brainstem and the vertebral artery.


Assuntos
Espasmo Hemifacial/etiologia , Artéria Vertebral/patologia , Artéria Vertebral/cirurgia , Idoso , Feminino , Humanos , Procedimentos Neurocirúrgicos/métodos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/métodos
10.
Vestn Ross Akad Med Nauk ; (3): 45-7, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7516222

RESUMO

A procedure has been developed for partial X-ray endovascular occlusion of the spleen in children. Splenic occlusion has been performed in 74 patients with various blood diseases and portal hypertension for 4 years. Indications for partial "disconnecting" of the splenic parenchyma have been identified depending on a specific disease. Its low traumatism, prevention of septic complications by using selective intestinal flora decontamination and choosing antibiotics at an individual level allow splenic occlusion to be made in young children. In patients with portal hypertension, partial splenic occlusion leads to decompression in the portal vein system and improves blood ejection along the natural vascular anastomoses.


Assuntos
Embolização Terapêutica , Doenças Hematológicas/complicações , Hipertensão Portal/complicações , Esplenopatias/terapia , Adolescente , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Constrição , Embolização Terapêutica/métodos , Endoscopia , Humanos , Lactente , Sistema Porta/diagnóstico por imagem , Radiografia , Esplenopatias/diagnóstico por imagem , Esplenopatias/etiologia
11.
Vestn Ross Akad Med Nauk ; (4): 11-2, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7516757

RESUMO

Transcatheter arterial chemotherapy has been perfected in the treatment of 66 patients with various severe malignant tumors. A total of 75 arterial cytostatic injections were made, out of them 57 were given in primary tumors and 18 in tumor metastases. The children's age ranged from 1 to 14 years. High arterial therapeutic doses in combination with extracorporeal blood purification by hemosorption in the treatment of hepatic metastases yielded 100% efficiency. Prolonged arterial chemotherapy for pulmonary metastases provided an excellent therapeutic effect. Thus, 75 arterial injections of cytostatics gave rise to 32% of complete remissions, 48% of partial remissions. There was no benefit in 20% of cases. Adverse reactions were absent.


Assuntos
Antineoplásicos/administração & dosagem , Infusões Intra-Arteriais , Neoplasias/tratamento farmacológico , Adolescente , Neoplasias Ósseas/tratamento farmacológico , Criança , Pré-Escolar , Humanos , Lactente , Neoplasias Renais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico
12.
Gematol Transfuziol ; 39(3): 36-9, 1994.
Artigo em Russo | MEDLINE | ID: mdl-8076793

RESUMO

Hemodynamics in the portal system was assessed at digital subtraction angiography in 57 children aged 9 months-15 years suffering from extrahepatic portal hypertension. Natural splenorenal anastomoses were found in 31 patients. 13 patients developed arteriovenous shunting into gastroesophageal plexus through the conglomerate of pathological vessels in the upper splenic pole. Partial occlusion of the spleen was performed in 12 patients aged 3-12 to block arteriovenous anastomoses and to reduce the blood flow from the spleen to the portal system. In various postocclusion periods blood effusion into gastric veins through arteriovenous shunts and retrograde flow via splenic vein and natural splenorenal anastomoses to the lower vena cava inferior were absent or drastically diminished. Septic complications were absent. Partial splenic occlusion in children with extrahepatic portal hypertension is considered valid.


Assuntos
Embolização Terapêutica , Hipertensão Portal/terapia , Baço/irrigação sanguínea , Adolescente , Criança , Pré-Escolar , Humanos , Lactente
13.
Phys Rev Lett ; 99(19): 192001, 2007 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-18233069

RESUMO

We present a new measurement of the difference between the nucleon strange and antistrange quark distributions from dimuon events recorded by the NuTeV experiment at Fermilab. This analysis is the first to use a complete next to leading order QCD description of charm production from neutrino scattering. Dimuon events in neutrino deep inelastic scattering allow direct and independent study of the strange and antistrange content of the nucleon. We find a positive strange asymmetry with a significance of 1.6sigma. We also report a new measurement of the charm mass.

14.
Artigo em Russo | MEDLINE | ID: mdl-8122464

RESUMO

Clinical and dynamic parameters of invalidity were studied in 105 schizophrenics with the disease duration more than 3 years. Of all the invalids registered in one of the Moscow dispensaries subjects with long-term invalidity account for 85%, and for 34% of the total number of registered schizophrenics. By social and occupational adaptation the patients may be divided into 2 groups: patients with stable disability (group 1) and patients with incomplete disability (group 2), these groups entering 49 and 56 schizophrenics, respectively. Occupational readaptation of the latter depended on endogenic-processual, social and personality factors. Parameters of invalidity were followed-up with the disease course. A differential approach to social-rehabilitation policy basing on real work capacity of the patients is validated.


Assuntos
Avaliação da Deficiência , Esquizofrenia/diagnóstico , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reabilitação Vocacional , Esquizofrenia/classificação , Esquizofrenia/reabilitação , Ajustamento Social , Fatores de Tempo , U.R.S.S.
15.
Phys Rev Lett ; 87(25): 251802, 2001 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-11736561

RESUMO

We report on the extraction of R = sigma(L)/sigma(T) from CCFR nu(mu)-Fe and nu(mu)-Fe differential cross sections. The CCFR differential cross sections do not show the deviations from the QCD expectations that are seen in the CDHSW data at very low and very high x. R as measured in nu(mu) scattering is in agreement with R as measured in muon and electron scattering. All data on R for Q(2)>1 GeV(2) are in agreement with a NNLO QCD calculation which uses NNLO parton distribution functions and includes target mass effects. We report on the first measurements of R in the low x and Q(2)<1 GeV(2) region (where an anomalous large rise in R for nuclear targets has been observed by the HERMES Collaboration).

16.
Phys Rev Lett ; 86(13): 2742-5, 2001 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-11290028

RESUMO

We report on the extraction of the structure functions F2 and DeltaxF(3) = xF(nu)(3)-xF(nu;)(3) from CCFR nu(mu)-Fe and nu;(mu)-Fe differential cross sections. The extraction is performed in a physics model-independent (PMI) way. This first measurement of DeltaxF(3), which is useful in testing models of heavy charm production, is higher than current theoretical predictions. The ratio of the F2 (PMI) values measured in nu(mu) and mu scattering is in agreement (within 5%) with the predictions of next-to-leading-order parton distribution functions using massive charm production schemes, thus resolving the long-standing discrepancy between the two sets of data.

17.
Phys Rev Lett ; 86(24): 5430-3, 2001 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-11415268

RESUMO

A new structure function analysis of CCFR deep inelastic nu-N and nu-N scattering data is presented for previously unexplored kinematic regions down to Bjorken x = 0.0045 and Q(2) = 0.3 GeV(2). Comparisons to charged lepton scattering data from NMC and E665 experiments are made and the behavior of the structure function F(2)(nu)2 is studied in the limit Q(2)-->0.

18.
Phys Rev Lett ; 87(4): 041801, 2001 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-11461608

RESUMO

A search for long-lived neutral particles ( N0's) with masses above 2.2 GeV/c(2) that decay into at least one muon has been performed using an instrumented decay channel at the NuTeV experiment at Fermilab. Data were examined for particles decaying into the final states mumu, mu(e), and mu(pi). Three mumu events were observed over an expected standard model background of 0.069+/-0.010 events; no events were observed in the other modes.

19.
Phys Rev Lett ; 87(7): 071803, 2001 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-11497881

RESUMO

The NuTeV experiment at Fermilab has used a sign-selected neutrino beam to perform a search for the lepton number violating process nu(mu)e(-)-->mu(-)nu(e), and to measure the cross section of the standard model inverse muon decay process nu(mu)e(-)-->mu(-)nu(e). NuTeV measures the inverse muon decay asymptotic cross-section slope sigma/E to be (13.8 +/- 1.2 +/- 1.4) x 10(-42) cm(2)/GeV. The experiment also observes no evidence for lepton number violation and places one of the most restrictive limits on the cross-section ratio sigma(nu(mu)e(-)-->mu(-)nu(e))/sigma(nu(mu)e(-)-->mu(-)nu(e)) < or = 1.7% at 90% C.L. for V-A couplings and < or = 0.6% for scalar couplings.

20.
Phys Rev Lett ; 89(1): 011804, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12097033

RESUMO

Limits on nu(mu)-->nu(e) and nu(mu)-->nu(e) oscillations are extracted using the NuTeV detector with sign-selected nu(mu) and nu(mu) beams. In nu(mu) mode, for the case of sin(2)2alpha = 1, Delta(m)(2)>2.6 eV(2) is excluded, and for Delta(m)(2)>>1000 eV(2), sin(2)2alpha>1.1 x 10(-3). The NuTeV data exclude the high Delta(m)(2) end of nu(mu)-->nu(e) oscillation parameters favored by the LSND experiment without the need to assume that the oscillation parameters for nu and nu are the same. We present the most stringent experimental limits for nu(mu)(nu(mu))-->nu(e)(nu(e)) oscillations in the large Delta(m)(2) region.

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