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1.
Stomatologiia (Mosk) ; 103(2): 12-17, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38741529

RESUMO

OBJECTIVE: The aim of the sthudy is to sthudy the level of soluble Immune Checkpoint Molecules (B7.2, CTLA-4, Tim-3, Lag-3, PD-1) in the oral fluid during dental caries with the background of a lack and/or deficiency of 25-hydroxy-vitamin D in body. MATERIALS AND METHODS: During the research 3 groups of people were formed, each one of them included 17 people aged from 20 to 24 years. The first group included students with high-intensity caries (above 9 DMFt index) and 25-hydroxy-vitamin D levels in blood serum >30 ng/ml, the second included students with high caries intensity and 25-hydroxy-vitamin D levels <30 ng/ml. The control group consisted of students with an average DMFt index of 1.5 (from 0 to 3) and a level of 25(OH)D in the blood more than 30 ng/ml. To determine the content of B7.2 (CD86), CTLA-4, Tim-3, Lag-3, PD-1, the Human Vascular Inflammation Panel 1 multiplex analysis kit from Biolegend (USA) was used. RESULTS: The results of the research showed that during dental caries with a normal level of 25-hydroxy-vitamin D there are no significant changes in the content of Immune Checkpoint Molecules. With the background of deficiency and lack of 25-hydroxy-vitamin D there is a decrease in the amount of B7.2, LAG-3, Tim-3 and PD-1. These changes are being aggravated with an increase of the caries intensity. CONCLUSION: Vitamin D deficiency leads to a decrease in mucosal immunity of the oral cavity, the multiplication of pathogenic microorganisms, which in turn, releasing various metabolites, including cytokine-like substances, aggravate the pathological process and intensify carious lesions.


Assuntos
Cárie Dentária , Saliva , Deficiência de Vitamina D , Vitamina D , Humanos , Cárie Dentária/imunologia , Adulto Jovem , Vitamina D/sangue , Vitamina D/análogos & derivados , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/imunologia , Deficiência de Vitamina D/complicações , Masculino , Feminino , Saliva/química , Adulto , Proteínas de Checkpoint Imunológico/metabolismo , Proteínas de Checkpoint Imunológico/análise
2.
Acta Psychiatr Scand ; 136(5): 517-525, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28940401

RESUMO

OBJECTIVE: The posterior superior temporal sulcus (pSTS) plays a critical role in the 'social brain'. Its neurodevelopment and relationship with the social impairment in autism spectrum disorders (ASD) are not well understood. We explored the relationship between social cognition and the neurodevelopment of the pSTS in ASD. METHOD: We included 44 adults with high-functioning ASD and 36 controls. We assessed their performances on the 'Reading the mind in the eyes' test (for 34 of 44 subjects with ASD and 30 of 36 controls), their fixation time on the eyes with eye tracking (for 35 of 44 subjects with ASD and 30 of 36 controls) and the morphology of the caudal branches of the pSTS (length and depth), markers of the neurodevelopment, with structural MRI. RESULTS: The right anterior caudal ramus of the pSTS was significantly longer in patients with ASD compared with controls (52.6 mm vs. 38.3 mm; P = 1.4 × 10-3 ; Cohen's d = 0.76). Its length negatively correlated with fixation time on the eyes (P = 0.03) in the ASD group and with the 'Reading the mind in the eyes' test scores in both groups (P = 0.03). CONCLUSION: Our findings suggest that the neurodevelopment of the pSTS is related to the ASD social impairments.


Assuntos
Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/fisiopatologia , Percepção Social , Lobo Temporal/crescimento & desenvolvimento , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Temporal/diagnóstico por imagem , Adulto Jovem
3.
Khirurgiia (Mosk) ; (5): 17-25, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27271715

RESUMO

AIM: To analyze the role of ray functional computerized diagnostic technologies in assessment of the state of tracheal wall in cicatricial stenosis. MATERIAL AND METHODS: We examined 45 patients with cicatricial tracheal stenosis during August 2013 -- March 2015. Fibrobronchoscopy, multislice computerized tomography, magnetic resonance imaging and lungs function examination were performed. For the first time dynamic (functional) CT and MRI were included in research algorithm. These techniques have not been used for cicatricial stenosis and tracheomalacia in our country until this moment. Circular resection with anastomosis was made in 38 patients and stage reconstructions were preferred in 7 cases. Last ones had advanced tracheomalacia on the background of cicatrical stenosis that forced to abandon from tracheal resection. So time to treatment and incidence of complications and recurrences were reduced and the results were improved. CONCLUSION: Endoscopy remains the main method of diagnosis of tracheal stenosis despite its invasiveness. Data of cicatrical transformation of tracheal wall per se can be obtained non-invasively using dynamic CT and MRI. These techniques help to identify or exclude tracheomalacia. They potentially complement fibrobronchoscopy and may be preferable to assess perioperative intramural pathological changes of the trachea.


Assuntos
Anastomose Cirúrgica , Cicatriz/complicações , Procedimentos de Cirurgia Plástica , Complicações Pós-Operatórias , Traqueia/patologia , Estenose Traqueal/diagnóstico , Traqueomalácia/diagnóstico , Adulto , Algoritmos , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/métodos , Endoscopia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos , Federação Russa , Tempo para o Tratamento , Tomografia Computadorizada Espiral/métodos , Traqueia/cirurgia , Estenose Traqueal/etiologia , Estenose Traqueal/cirurgia , Traqueomalácia/etiologia , Traqueomalácia/cirurgia , Resultado do Tratamento
5.
Comput Math Methods Med ; 2015: 479014, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26543495

RESUMO

Amongst large a variety of oncological diseases, malignant gliomas represent one of the most severe types of tumors. They are also the most common type of the brain tumors and account for over half of the astrocytic tumors. According to different sources, the average life expectancy of patients with various glioblastomas varies between 10 and 12 months and that of patients with anaplastic astrocytic tumors between 20 and 24 months. Therefore, studies of the physiology of transformed glial cells are critical for the development of treatment methods. Modern medical approaches offer complex procedures, including the microsurgical tumor removal, radiotherapy, and chemotherapy, supplemented with photodynamic therapy and immunotherapy. The most radical of them is surgical resection, which allows removing the largest part of the tumor, reduces the intracranial hypertension, and minimizes the degree of neurological deficit. However, complete removal of the tumor remains impossible. The main limitations are insufficient visualization of glioma boundaries, due to its infiltrative growth, and the necessity to preserve healthy tissue. This review is devoted to the description of advantages and disadvantages of modern intraoperative diagnostics of human gliomas and highlights potential perspectives for development of their treatment.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirurgia , Glioma/diagnóstico , Glioma/cirurgia , Neoplasias Encefálicas/fisiopatologia , Movimento Celular , Biologia Computacional , Glioma/fisiopatologia , Ácido Glutâmico/metabolismo , Humanos , Biópsia Guiada por Imagem , Período Intraoperatório , Imageamento por Ressonância Magnética , Imagem Óptica , Cirurgia Assistida por Computador , Ultrassonografia
6.
Artigo em Russo | MEDLINE | ID: mdl-23113363

RESUMO

The objective of the present study was to develop a new technology for the balneotherapeutic treatment of the patients with urolithiasis by means of combined application of mineral water, mineral baths (1 therapeutic complex), sinusoidal modulated current (SMC-phoresis of nicotinamide), and preparations inhibiting urine concrement formation. The overall efficacy of this combined balneo-, physio-, radio-, and pharmacotherapy of the patients presenting with secondary calculous pyelonephritis amounted to 94% compared with 73.4% using balneotherapy alone (p1-2 < 0.05). Summation of positive effects of balneo-, physio-, radio-, and pharmacotherapies promoted normalization of the functional state of the kidneys and the upper urinary tracts which in its turn contributed to the improvement of the patient's quality of life.


Assuntos
Balneologia/métodos , Cálculos Renais/reabilitação , Pielonefrite/reabilitação , Recuperação de Função Fisiológica , Adulto , Doença Crônica , Feminino , Humanos , Rim/fisiopatologia , Cálculos Renais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pielonefrite/fisiopatologia
7.
Klin Lab Diagn ; (10): 27-9, 2009 Oct.
Artigo em Russo | MEDLINE | ID: mdl-20000111

RESUMO

A simple and highly sensitive high-performance liquid chromatography assay is proposed to test salivary diamines (putrescine and cadaverine). Derivation was carried out with the orthophthalic aldehyde 2-mercaptoethanol. A rapid purification procedure for derivatives on the cartridges packed with 10 mg of hypercrosslinked polystyrene (Purosep-200) was first developed. Separation was made on a Chromolith (Merck), 100 x 4.6 mm in size, with monolithic reverse-phase silica gel (RP-18e) in the isocratic mode with ultraviolet (UV) detection at 230 nm. The eluent contained 55% acetonitrile and 45% 0.01 M phosphate buffer pH 6.8, added by 1% of isopropanol; flow rate was 1400 pl/min; pressure was 28 bars. Complete separation of diamine derivatives lasted at least 5 min. The sensitivity of the assay with UV detection (230 nm) was about 0.1 ngfor diamines and about 0.5 ng for the internal standard (IS) at a signal/noise ratio of 3.0, which enabled diamines to be determined in I pl (0.001 ml) of saliva. The simplicity, reproducibility, and high sensitivity of the assay along with the feasibility of its application on standard chromatographic equipment (an isocratic pump and an UV detector) make it suitable for routine clinical application.


Assuntos
Cadaverina/análise , Putrescina/análise , Saliva/química , Cromatografia Líquida de Alta Pressão , Humanos
8.
Appl Opt ; 40(9): 1532-47, 2001 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-18357146

RESUMO

The transverse wave condition is not applicable to the refracted electromagnetic wave within the context of geometrical optics when absorption is involved. Either the TM or the TE wave condition can be assumed for the wave to locally satisfy the electromagnetic boundary condition in a ray-tracing calculation. The assumed wave mode affects both the reflection and the refraction coefficients. As a result, nonunique solutions for these coefficients are inevitable. In this study the appropriate solutions for the Fresnel reflection-refraction coefficients are identified in light-scattering calculations based on the ray-tracing technique. In particular, a 3 x 2 refraction or transmission matrix is derived to account for the inhomogeneity of the refracted wave in an absorbing medium. An asymptotic solution that completely includes the effect of medium absorption on Fresnel coefficients is obtained for the scattering properties of a general polyhedral particle. Numerical results are presented for hexagonal plates and columns with both preferred and random orientations.

9.
Klin Khir ; (2): 25-8, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10857283

RESUMO

There were examined 72 patients with phlegmon, abscess and infected wound of the upper and lower extremities soft tissues. The efficacy of dalargin application for improvement of processes of the purulent wound clearance and reparation was shown using rheologic, biochemical, cytological and planimetric methods of control of the wound process course.


Assuntos
Abscesso/terapia , Infecção dos Ferimentos/terapia , Humanos , Imunoeletroforese/métodos , Sistema Linfático/fisiologia , Sucção/métodos , Fatores de Tempo , Cicatrização
10.
Appl Opt ; 39(6): 1026-31, 2000 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-18337981

RESUMO

General equations are derived for computing the amplitude matrix for a nonspherical particle in an arbitrary orientation and for arbitrary illumination and scattering directions with respect to the laboratory reference frame, provided that the scattering problem can be solved with respect to the particle reference frame. These equations are used along with the T-matrix method to provide benchmark results for homogeneous, dielectric, rotationally symmetric particles. The computer code is publicly available on the World-Wide Web at http://www.giss.nasa.gov/~crmim.

11.
Appl Opt ; 39(21): 3727-37, 2000 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-18349948

RESUMO

We have examined the Maxwell-Garnett, inverted Maxwell-Garnett, and Bruggeman rules for evaluation of the mean permittivity involving partially empty cells at particle surface in conjunction with the finite-difference time-domain (FDTD) computation. Sensitivity studies show that the inverted Maxwell-Garnett rule is the most effective in reducing the staircasing effect. The discontinuity of permittivity at the interface of free space and the particle medium can be minimized by use of an effective permittivity at the cell edges determined by the average of the permittivity values associated with adjacent cells. The efficiency of the FDTD computational program is further improved by use of a perfectly matched layer absorbing boundary condition and the appropriate coding technique. The accuracy of the FDTD method is assessed on the basis of a comparison of the FDTD and the Mie calculations for ice spheres. This program is then applied to light scattering by convex and concave aerosol particles. Comparisons of the scattering phase function for these types of aerosol with those for spheres and spheroids show substantial differences in backscattering directions. Finally, we illustrate that the FDTD method is robust and flexible in computing the scattering properties of particles with complex morphological configurations.

12.
Appl Opt ; 39(27): 5052-7, 2000 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-18350104

RESUMO

We use the current advanced version of the T-matrix method to compute the optical cross sections, the asymmetry parameter of the phase function, and the scattering matrix elements of ice spheroids with aspect ratios up to 20 and surface-equivalent-sphere size parameters up to 12. We demonstrate that platelike and needlelike particles with moderate size parameters possess unique scattering properties: their asymmetry parameters and phase functions are similar to those of surface-equivalent spheres, whereas all other elements of the scattering matrix are typical of particles much smaller than the wavelength (Rayleigh scatterers). This result may have important implications for optical particle sizing and remote sensing of the terrestrial and planetary atmospheres.

13.
Appl Opt ; 38(9): 1626-9, 1999 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-18305781

RESUMO

It has been hypothesized that the frequent lack of halos in observations of cirrus and contrails and laboratory measurements is caused by small ice crystal sizes that put the particles outside the geometrical optics domain of size parameters. We test this hypothesis by exploiting a strong similarity of ray tracing phase functions for finite hexagonal and circular ice cylinders and using T-matrix computations of electromagnetic scattering by circular cylinders with size parameters up to 180 in the visible. We conclude that well-defined halos should be observable for ice crystal size parameters of the order of 100 and larger and discuss remote-sensing implications of this result.

14.
Appl Opt ; 38(36): 7325-41, 1999 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-18324281

RESUMO

We outline the methodology of interpreting channels 1 and 2 Advanced Very High Resolution Radiometer (AVHRR) radiance data over the oceans and describe a detailed analysis of the sensitivity of monthly averages of retrieved aerosol parameters to the assumptions made in different retrieval algorithms. The analysis is based on using real AVHRR data and exploiting accurate numerical techniques for computing single and multiple scattering and spectral absorption of light in the vertically inhomogeneous atmosphere-ocean system. We show that two-channel algorithms can be expected to provide significantly more accurate and less biased retrievals of the aerosol optical thickness than one-channel algorithms and that imperfect cloud screening and calibration uncertainties are by far the largest sources of errors in the retrieved aerosol parameters. Both underestimating and overestimating aerosol absorption as well as the potentially strong variability of the real part of the aerosol refractive index may lead to regional and/or seasonal biases in optical-thickness retrievals. The Angström exponent appears to be the aerosol size characteristic that is least sensitive to the choice of aerosol model and should be retrieved along with optical thickness as the second aerosol parameter.

15.
Appl Opt ; 36(18): 4305-13, 1997 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-18253460

RESUMO

We show that the use of a matrix inversion scheme based on a special lower triangular-upper triangular factorization rather than on the standard Gaussian elimination significantly improves the numerical stability of T-matrix computations for nonabsorbing and weakly absorbing nonspherical particles. As a result, the maximum convergent size parameter for particles with small or zero absorption can increase by a factor of several and can exceed 100. We describe an improved scheme for evaluating Clebsch-Gordon coefficients with large quantum numbers, which allowed us to extend the analytical orientational averaging method developed by Mishchenko [J. Opt. Soc. Am. A 8, 871 (1991)] to larger size parameters. Comparisons of T-matrix and geometrical optics computations for large, randomly oriented spheroids and finite circular cylinders show that the applicability range of the ray-tracing approximation depends on the imaginary part of the refractive index and is different for different elements of the scattering matrix.

16.
Opt Lett ; 21(9): 623-5, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19876104

RESUMO

Rigorous numerical solutions of Maxwell's equations are used to show, for what is believed to be the first time, that simple scattering systems composed of two interacting wavelength-sized spheres exhibit a coherent backscattering effect analogous to that observed previously for optically thick discrete random media comprising large numbers of scatterers.

17.
Appl Opt ; 35(21): 4291-6, 1996 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21102838

RESUMO

We ascertain the usefulness of simple ice particle geometries for modeling the intensity distribution of light scattering by atmospheric ice particles. To this end, similarities and differences in light scattering by axis-equivalent, regular and distorted hexagonal cylindric, ellipsoidal, and circular cylindric ice particles are reported. All the results pertain to particles with sizes much larger than a wavelength and are based on a geometrical optics approximation. At a nonabsorbing wavelength of 0.55 µm, ellipsoids (circular cylinders) have a much (slightly) larger asymmetry parameter g than regular hexagonal cylinders. However, our computations show that only random distortion of the crystal shape leads to a closer agreement with g values as small as 0.7 as derived from some remote-sensing data analysis. This may suggest that scattering by regular particle shapes is not necessarily representative of real atmospheric ice crystals at nonabsorbing wavelengths. On the other hand, if real ice particles happen to be hexagonal, they may be approximated by circular cylinders at absorbing wavelengths.

18.
Appl Opt ; 35(24): 4927-40, 1996 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-21102919

RESUMO

We use the T-matrix method, as described by Mishchenko [Appl. Opt. 32, 4652 (1993)], to compute rigorously light scattering by finite circular cylinders in random orientation. First we discuss numerical aspects of T -matrix computations specific for finite cylinders and present results of benchmark computations for a simple cylinder model. Then we report results of extensive computations for polydisperse, randomly oriented cylinders with a refractive index of 1.53 + 0.008i, diameter-to-length ratios of 1/2, 1/1.4, 1, 1.4, and 2, and effective size parameters ranging from 0 to 25. These computations parallel our recent study of light scattering by polydisperse, randomly oriented spheroids and are used to compare scattering properties of the two classes of simple convex particles. Despite the significant difference in shape between the two particle types (entirely smooth surface for spheroids and sharp rectangular edges for cylinders), the comparison shows rather small differences in the integral photometric characteristics (total optical cross sections, single-scattering albedo, and asymmetry parameter of the phase function) and the phase function. The general patterns of the other elements of the scattering matrix for cylinders and aspect-ratio-equivalent spheroids are also qualitatively similar, although noticeable quantitative differences can be found in some particular cases. In general, cylinders demonstrate much less shape dependence of the elements of the scattering matrix than do spheroids. Our computations show that, like spheroids and bispheres, cylinders with surface-equivalent radii smaller than a wavelength can strongly depolarize backscattered light, thus suggesting that backscattering depolarization for nonspherical particles cannot be universally explained by using only geometric-optics considerations.

19.
Opt Lett ; 20(12): 1356-8, 1995 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19862013

RESUMO

We derive theoretically and validate numerically general relationships for the elements of the backscattering matrix and for the linear, delta(L), and circular, delta(C), backscattering depolarization ratios for nonspherical particles in random orientation. For the practically important case of randomly oriented particles with a plane of symmetry or particles and their mirror particles occurring in equal numbers and in random orientation, delta(C) = 2delta(L)/(1 - delta(L)). Extensive T-matrix computations for randomly oriented spheroids demonstrate that, although both delta(L) and delta(C) are indicators of particle nonsphericity, they cannot be considered a universal measure of the departure of particle shape from that of a sphere and have no simple dependence on particle size and refractive index.

20.
Opt Lett ; 20(19): 1934-6, 1995 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19862208

RESUMO

We report, for the f irst time to our knowledge, comparisons of light-scattering computations for large, randomly oriented, moderately absorbing spheroids based on the geometric-optics approximation and the exact T-matrix method. We show that in most cases the geometric-optics approximation is (much) more accurate for spheroids than for surface-equivalent spheres and can be used in phase function computations (but not in polarization computations) for nonspherical particles with size parameters as small as 60. Differences in the single-scattering albedo between geometric-optics and T-matrix results are surprisingly small, even for small size parameters.

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