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1.
Placenta ; 33(10): 885-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22877695

RESUMO

Galectin 4 (Gal4) is abundantly expressed in the epithelium of the gastrointestinal tract, and functional analysis has concentrated on its roles associated with polarized membrane trafficking. This study aimed to investigate the expression of Gal4 in placentation. The expression level of Gal4 was revealed to be lower in differentiated Rcho-1 cells (a model system of rat trophoblast differentiation) than in proliferative cells. In the rat placenta, immunohistochemical analysis showed that Gal4 is preferentially located in the maternal-fetal junctional zone. These results suggest that down-regulation of Gal4 may be involved in the promotion of trophoblast cell differentiation.


Assuntos
Galectina 4/biossíntese , Placentação/fisiologia , Animais , Diferenciação Celular/fisiologia , Regulação para Baixo , Feminino , Placenta/metabolismo , Gravidez , Ratos
2.
Phys Rev Lett ; 107(3): 035004, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21838370

RESUMO

A three-dimensional, nonlinear gyrokinetic simulation of plasma turbulence resolving scales from the ion to electron gyroradius with a realistic mass ratio is presented, where all damping is provided by resolved physical mechanisms. The resulting energy spectra are quantitatively consistent with a magnetic power spectrum scaling of k(-2.8) as observed in in situ spacecraft measurements of the "dissipation range" of solar wind turbulence. Despite the strongly nonlinear nature of the turbulence, the linear kinetic Alfvén wave mode quantitatively describes the polarization of the turbulent fluctuations. The collisional ion heating is measured at subion-Larmor radius scales, which provides evidence of the ion entropy cascade in an electromagnetic turbulence simulation.

3.
Phys Rev Lett ; 106(16): 165003, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21599375

RESUMO

The question of how nonlinear interactions redistribute the energy of fluctuations across available degrees of freedom is of fundamental importance in the study of turbulence and transport in magnetized weakly collisional plasmas, ranging from space settings to fusion devices. In this Letter, we present a theory for the dual cascade found in such plasmas, which predicts a range of new behavior that distinguishes this cascade from that of neutral fluid turbulence. These phenomena are explained in terms of the constrained nature of spectral transfer in nonlinear gyrokinetics. Accompanying this theory are the first observations of these phenomena, obtained via direct numerical simulations using the gyrokinetic code AstroGK. The basic mechanisms that are found provide a framework for understanding the turbulent energy transfer that couples scales both locally and nonlocally.

4.
Phys Rev Lett ; 103(1): 015003, 2009 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-19659155

RESUMO

Electrostatic turbulence in weakly collisional, magnetized plasma can be interpreted as a cascade of entropy in phase space, which is proposed as a universal mechanism for dissipation of energy in magnetized plasma turbulence. When the nonlinear decorrelation time at the scale of the thermal Larmor radius is shorter than the collision time, a broad spectrum of fluctuations at sub-Larmor scales is numerically found in velocity and position space, with theoretically predicted scalings. The results are important because they identify what is probably a universal Kolmogorov-like regime for kinetic turbulence; and because any physical process that produces fluctuations of the gyrophase-independent part of the distribution function may, via the entropy cascade, result in turbulent heating at a rate that increases with the fluctuation amplitude, but is independent of the collision frequency.

5.
Phys Rev Lett ; 100(6): 065004, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18352484

RESUMO

This Letter presents the first ab initio, fully electromagnetic, kinetic simulations of magnetized turbulence in a homogeneous, weakly collisional plasma at the scale of the ion Larmor radius (ion gyroscale). Magnetic- and electric-field energy spectra show a break at the ion gyroscale; the spectral slopes are consistent with scaling predictions for critically balanced turbulence of Alfvén waves above the ion gyroscale (spectral index -5/3) and of kinetic Alfvén waves below the ion gyroscale (spectral indices of -7/3 for magnetic and -1/3 for electric fluctuations). This behavior is also qualitatively consistent with in situ measurements of turbulence in the solar wind. Our findings support the hypothesis that the frequencies of turbulent fluctuations in the solar wind remain well below the ion cyclotron frequency both above and below the ion gyroscale.

6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(6 Pt 2): 066409, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15697516

RESUMO

A Suydam-unstable circular cylinder of plasma with periodic boundary conditions in the axial direction is studied within the approximation of linearized ideal magnetohydrodynamics (MHD). The normal mode equations are completely separable, so both the toroidal Fourier harmonic index n and the poloidal index m are good quantum numbers. The full spectrum of eigenvalues in the range 1< or = m < or = m(max) is analyzed quantitatively, using asymptotics for large m, numerics for all m, and graphics for qualitative understanding. The density of eigenvalues scales like m(2)(max) as m(max) -->infinity . Because finite-m corrections scale as 1/ m(2)(max) , their inclusion is essential in order to obtain the correct statistics for the distribution of eigenvalues. Near the largest growth rate, only a single radial eigenmode contributes to the spectrum, so the eigenvalues there depend only on m and n as in a two-dimensional system. However, unlike the generic separable two-dimensional system, the statistics of the ideal-MHD spectrum departs somewhat from the Poisson distribution, even for arbitrarily large m(max) . This departure from Poissonian statistics may be understood qualitatively from the nature of the distribution of rational numbers in the rotational transform profile.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 68(1 Pt 2): 016409, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12935260

RESUMO

Creation of angular momentum in a relativistic electron-positron plasma is explored. It is shown that a chain of angular momentum carrying vortices is a robust asymptotic state sustained by the generalized nonlinear Schrödinger equation characteristic to the system. The results may suggest a possible electromagnetic origin of angular momenta when it is applied to the MeV epoch of the early Universe.

8.
Clin Exp Immunol ; 132(1): 152-7, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12653850

RESUMO

In sarcoidosis, a T helper 1 (Th1) response is an essential event and the up-regulation of interleukin-12 (IL-12) has been detected in affected disease sites. In order to investigate the clinical usefulness of circulating IL-12, we measured the serum concentrations of IL-12 by ELISA and performed immunohistochemistry using specific MoAbs for IL-12 in the lungs and scalene lymph nodes of patients with sarcoidosis. The serum concentration of IL-12 p40 was detectable in all 45 patients with pulmonary sarcoidosis and 18 normal controls, whereas that of IL-12 p70 was undetectable. The serum concentrations of IL-12 p40 in pulmonary sarcoidosis were significantly higher than those of the normal controls, especially in cases with abnormal intrathoracic findings detected by chest roentogenogram. The serum concentrations of interferon-gamma (IFN-gamma) also increased compared with those of normal controls and there was a significant positive correlation between the serum concentrations of IL-12 p40 and IFN-gamma. Furthermore, serum angiotensin-converting enzyme (ACE) and lysozyme, which are known to be useful markers for disease activity in sarcoidosis, correlated well with the serum concentrations of IL-12 p40. The positive 67Ga scan group (for lung field) had significantly elevated serum IL-12 p40 levels compared with those of the negative group. No bioactivity of IL-12 p70 was detected in three sarcoid cases sera by using the IL-12 responsive cell line. Finally, the immunohistochemical approach revealed that IL-12 p40 was expressed in the epithelioid cells and macrophages of sarcoid lungs and lymph nodes. We concluded that the production of IL-12 p40 was far greater in the sera and we have demonstrated this to be a useful clinical marker for disease activity and the Th1 response in pulmonary sarcoidosis.


Assuntos
Isotipos de Imunoglobulinas/sangue , Interleucina-12/sangue , Sarcoidose Pulmonar/imunologia , Células Th1/imunologia , Análise de Variância , Biomarcadores/análise , Biomarcadores/sangue , Estudos de Casos e Controles , Linhagem Celular , Ensaio de Imunoadsorção Enzimática/métodos , Células Epitelioides/imunologia , Feminino , Humanos , Isotipos de Imunoglobulinas/análise , Imuno-Histoquímica/métodos , Interferon gama/biossíntese , Interferon gama/sangue , Interleucina-12/análise , Pulmão/diagnóstico por imagem , Pulmão/imunologia , Linfonodos/imunologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Muramidase/sangue , Peptidil Dipeptidase A/sangue , Cintilografia , Sarcoidose Pulmonar/diagnóstico por imagem
9.
Shokuhin Eiseigaku Zasshi ; 42(3): 210-4, 2001 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-11577396

RESUMO

Method-performance studies were conducted for the notified revised analytical method of fenbutatin oxide (FBTO) and cyhexatin (CHT). FBTO and CHT spiked into rice, soybeans, spinach, orange, tea powder and tea extract at the level of 0.5 microgram/g for FBTO and 0.1 microgram/g for CHT were analyzed in replicate in 6 laboratories. Means recoveries of FBTO were 85.2-96.5% and those of CHT were 83.5-89.2% except from soybeans (46.5%). Repeatability relative standard deviation values of FBTO and CHT in each crop were in the ranges of 2.3-9.4% and 3.2-6.3%, respectively. Reproducibility relative standard deviations were 3.9-12.6% for FBTO and 8.3-12.9% for CHT. Detection limits were 0.015-0.05 microgram/g for FBTO and 0.005-0.02 microgram/g for CHT.


Assuntos
Análise de Alimentos/normas , Compostos Orgânicos de Estanho/análise , Compostos de Trialquitina/análise , Reprodutibilidade dos Testes
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(4 Pt 2): 046403, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11308952

RESUMO

It is shown that the interaction of large amplitude electromagnetic waves with a hot electron-positron (e-p) plasma (a principal constituent of the universe in the MeV epoch) leads to a bunching of mass, energy, and angular momentum in stable, long-lived structures. Electromagnetism in the MeV epoch, then, could provide a possible route for seeding the observed large-scale structure of the universe.

11.
Neuroreport ; 12(5): 1067-72, 2001 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-11303747

RESUMO

Brain-derived neurotrophic factor (BDNF) belongs to the neurotrophin family and has been shown to be a potent and effective trophic factor for motor neurons and other neurons of the peripheral and central nervous. Little is known, however, about the relationship between the efficacy and pharmacokinetics of s.c. administered BDNF. In this study, the efficacy of BDNF on motor neuron protection in sciatic or facial nerve axotomy models was examined and compared with the concommitant concentrations of BDNF in plasma. Delayed treatment (started at 1 week after surgery) of BDNF was also shown to retard choline acetyltransferase reduction in sciatic nerve axotomy models.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Fator Neurotrófico Derivado do Encéfalo/farmacocinética , Fármacos Neuroprotetores/farmacologia , Animais , Axotomia , Fator Neurotrófico Derivado do Encéfalo/administração & dosagem , Colina O-Acetiltransferase/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Traumatismos do Nervo Facial/tratamento farmacológico , Traumatismos do Nervo Facial/patologia , Injeções Subcutâneas , Masculino , Neurônios Motores/efeitos dos fármacos , Ratos , Ratos Wistar , Nervo Isquiático/lesões
12.
Toxicon ; 39(2-3): 303-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-10978748

RESUMO

Cyclochlorotin (= chloropeptide, CC) is a hepatotoxic mycotoxin of Penicillium islandicum Sopp. The effect of CC on actin polymerization was examined by the measurement of changes in fluorescence intensity using pyrene-labeled actin and high shear viscosity. In the presence of CC, the time course of actin polymerization was accelerated in a dose dependent manner (2.5 ng/ml-2.5 microg/ml), without affecting the final level of viscosity. CC exerted a strong stabilizing effect on actin, enabling it to maintain its filamentous form in the presence of members of actin-binding proteins, including those of the gelsolin family prepared from hepatocytes. Microscopic observation revealed that in cultured hepatocytes, 1.0 microg/ml of CC induced bleb formation and changes in the microfilament. These observations indicated that after contact of the hepatocyte with CC, the following events were probable. The toxin passed through the cell membrane by a transport system and immediately reacted with the actin-actin binding proteins underlying the lipid bilayer. Bleb formation and hepatotoxicity were thus induced.


Assuntos
Actinas/efeitos dos fármacos , Fígado/efeitos dos fármacos , Micotoxinas/farmacologia , Peptídeos Cíclicos/farmacologia , Actinas/metabolismo , Animais , Células Cultivadas , Fígado/metabolismo , Masculino , Ratos , Ratos Endogâmicos Lew , Viscosidade/efeitos dos fármacos
13.
J Immunol ; 166(1): 642-9, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11123348

RESUMO

Sarcoidosis is a systemic chronic granulomatous disease of unknown cause. Recent investigations revealed that the cytokine profile in inflamed lesions of sarcoidosis is Th1 dominant. To obtain better immunopathologic understanding of sarcoidosis, we examined the expression of IL-12 and IL-18 and their roles in IFN-gamma production in pulmonary sarcoidosis. Sarcoid cases had significantly elevated levels of IL-12 (p40 and p70) and IL-18 in bronchoalveolar lavage (BAL) fluids compared with healthy subjects. IL-12 p70 and IL-18 were immunohistochemically expressed in the epithelioid cells and giant cells of sarcoid granulomas. Significant induction of IFN-gamma, IL-12 p70, and IL-18 was observed from sarcoid BAL fluid cells with LPS stimulation, whereas LPS tended to induce only IL-12 p70 in BAL fluid cells from healthy subjects. Sarcoid cases had significantly greater IFN-gamma induction with LPS stimulation than healthy subjects did. IL-18 mRNA expression was observed in freshly isolated sarcoid BAL fluid cells as well as in LPS-stimulated sarcoid BAL fluid cells, but IFN-gamma and IL-12 mRNA expression was observed only in LPS-stimulated BAL fluid cells. Treatment with anti-IL-12- and anti-IL-18-neutralizing Abs significantly inhibited IFN-gamma production from LPS-stimulated BAL fluid cells of sarcoid cases. Coadministration of rIL-12 or rIL-18 induced greater IFN-gamma production in sarcoid BAL fluid cells than in normal BAL fluid cells. We concluded that bioactive IL-12 and IL-18 were produced in sarcoid BAL fluid cells and synergistically induced IFN-gamma production, indicating important cytokines in the Th1 response of sarcoidosis.


Assuntos
Adjuvantes Imunológicos/fisiologia , Interferon gama/biossíntese , Interleucina-12/biossíntese , Interleucina-18/biossíntese , Sarcoidose Pulmonar/imunologia , Regulação para Cima/imunologia , Adulto , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Células Cultivadas , Feminino , Humanos , Soros Imunes/farmacologia , Indutores de Interferon/farmacologia , Interferon gama/antagonistas & inibidores , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-12/fisiologia , Interleucina-18/genética , Interleucina-18/imunologia , Interleucina-18/fisiologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , Proteínas Recombinantes/farmacologia , Sarcoidose Pulmonar/metabolismo , Regulação para Cima/genética
14.
Shokuhin Eiseigaku Zasshi ; 42(4): 269-72, 2001 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-11817144

RESUMO

Method-performance studies were conducted for the notified revised analytical method of inabenfide in unpolished rice. Six laboratories analyzed unpolished rice spiked with 0.05 microgram/g of inabenfide in replicate. Mean recovery from rice was 85.0%. Repeatability relative standard deviation value was 4.2% and reproducibility relative standard deviation value was 8.1%. The detection limits were 0.002-0.01 microgram/g.


Assuntos
Ácidos Isonicotínicos/análise , Oryza/química , Reguladores de Crescimento de Plantas/análise , Reprodutibilidade dos Testes
15.
Shokuhin Eiseigaku Zasshi ; 42(4): 273-7, 2001 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-11817145

RESUMO

Method-performance studies were conducted for the notified revised analytical method of chinomethionat in agricultural products by interlaboratory study. Six laboratories analyzed unpolished rice, cabbage, squash, lettuce and orange spiked with 0.1 microgram/g of chinomethionat in replicate. Mean values of recovery from the 5 crops ranged from 90.2 to 100.5%. Repeatability relative standard deviations ranged from 4.4 to 7.7% and reproducibility relative standard deviations ranged from 10.9 to 17.1%. The detection limits were 0.003-0.012 microgram/g.


Assuntos
Fungicidas Industriais/análise , Quinoxalinas/análise , Brassica/química , Cucurbita/química , Análise de Alimentos/métodos , Frutas/química , Lactuca/química , Oryza/química , Reprodutibilidade dos Testes
16.
Shokuhin Eiseigaku Zasshi ; 42(4): 278-82, 2001 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-11817146

RESUMO

Method-performance studies were conducted for the notified revised analytical method of clofentezine. Clofentezine spiked in azuki beans, apple, orange, banana, grape, tea powder and tea extract at the level of 0.2 microgram/g (2 micrograms/g for tea) was analyzed in replicate in 6 laboratories. Mean values of recovery from 7 crops ranged from 78.4 to 85.2%. Repeatability relative standard deviation values ranged from 2.2 to 4.6% and reproducibility standard deviation values ranged from 4.8 to 10.3%. The detection limits were 0.005-0.01 microgram/g. These results show the notified analytical method has good performance.


Assuntos
Clorobenzenos/análise , Inseticidas/análise , Fabaceae/química , Frutas/química , Malus/química , Musa/química , Reprodutibilidade dos Testes , Chá/química , Vitis/química
17.
Am J Respir Crit Care Med ; 162(5): 1979-82, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11069843

RESUMO

Interleukin-18 (IL-18) has recently been identified as an interferon-gamma (IFN-gamma)-inducing factor, and it plays an important role in T helper 1 (Th1) response. We measured the serum levels of IL-18 and IFN- gamma in 37 patients with pulmonary sarcoidosis and 25 healthy control subjects. We also measured the levels of IL-18 and IFN-gamma in 10-fold concentrated bronchoalveolar lavage (BAL) fluids of 19 patients with pulmonary sarcoidosis and 9 healthy control subjects (all lifelong nonsmokers). The levels of serum IL-18 and IFN-gamma were significantly increased in patients with sarcoidosis. The levels of BAL fluid IL-18 were significantly elevated in patients with sarcoidosis, however, the IFN-gamma levels of the patients and control subjects were all below sensitivity. Serum IL-18 levels significantly correlated with serum IFN-gamma levels and lysozyme activity. The patients positive for gallium-67 ((67)Ga) scan had significantly elevated serum IL-18 levels as compared with those of the negative patients. BAL fluid IL-18 levels significantly correlated with serum IL-18 levels in patients with sarcoidosis, and there was a significant correlation between IL-18 levels and lymphocyte proportions in sarcoid BAL fluids. In patients with sarcoidosis, IL-18 seems to induce IFN-gamma production and IL-18 levels in sera may reflect disease activity of sarcoidosis.


Assuntos
Interleucina-18/análise , Sarcoidose Pulmonar/metabolismo , Adulto , Líquido da Lavagem Broncoalveolar/química , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interferon gama/análise , Interferon gama/sangue , Interleucina-18/sangue , Masculino , Pessoa de Meia-Idade
18.
Brain Res ; 884(1--2): 59-67, 2000 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-11082487

RESUMO

PURPOSE: To determine if brain-derived neurotrophic factor (BDNF) has a neuroprotective effect against N-methyl-D-aspartate (NMDA)-induced cell death in retina. METHODS: NMDA was injected into the vitreous of rat eyes. NMDA-induced neuronal death was measured by morphometric analyses on cell counts of ganglion cell layer cells and thickness of retinal layers. Also, we conducted additional experiment using retrograde labeling with a fluorescent tracer (Fluoro-Gold) for exact counting of retinal ganglion cells (RGCs). In addition, intravitreal glutamate levels were measured with the use of a high-performance liquid chromatography (HPLC) system. RESULTS: Morphometric analysis of retinal damage in NMDA-injected eyes showed that BDNF could protect inner retinal cells from glutamate receptor-mediated neuronal death. Also, counts of RGCs labeled with a fluorescent tracer showed that BDNF could protect RGCs from glutamate receptor-mediated neuronal death. Furthermore, measurements of intravitreal glutamate levels indicated an increase in this excitatory amino acid in the vitreous after NMDA injection. CONCLUSIONS: Exogenous BDNF can protect inner retinal cells (possible RGCs and amacrine cells) from NMDA-induced neuronal death. However, increased intravitreal glutamate levels in response to NMDA-mediated neurotoxicity may augment retinal degeneration.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Morte Celular/efeitos dos fármacos , N-Metilaspartato/toxicidade , Degeneração Neural/tratamento farmacológico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Retina/efeitos dos fármacos , Estilbamidinas , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Contagem de Células/estatística & dados numéricos , Morte Celular/fisiologia , Corantes Fluorescentes , Ácido Glutâmico/metabolismo , Masculino , Degeneração Neural/induzido quimicamente , Degeneração Neural/patologia , Neurônios/metabolismo , Neurônios/patologia , Neurotoxinas/metabolismo , Neurotoxinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/metabolismo , Retina/patologia , Retina/fisiopatologia , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Corpo Vítreo/metabolismo
19.
Sarcoidosis Vasc Diffuse Lung Dis ; 17(2): 151-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10957763

RESUMO

BACKGROUND AND AIM OF THE WORK: Active sarcoidosis is considered to be a Th1 dominant condition. We examined whether Th1 cytokines are highly expressed at inflammed lesions of Japanese patients with sarcoidosis. METHODS: To investigate the mRNA expression of Th1 cytokines and IL-12 in sarcoid BAL cells, we used semiquantitative reverse transcription--polymerase chain reaction method. RESULTS: The mRNA expressions of Th1 cytokines (IFN-gamma and IL-2) in active sarcoid BAL cells were significantly elevated as compared with those in healthy volunteers. The proportion of positive IL-4 mRNA expression in sarcoid BAL cells was not significantly higher than that in healthy volunteers. Further, there was no significant difference in IFN-gamma mRNA levels between the groups positive and negative for IL-4 mRNA expression. Although the proportion of positive expression of IL-12 mRNA in active sarcoid BAL cells was not significantly higher than that in healthy volunteers, the group positive for IL-12 mRNA expression had significantly elevated levels of IFN-gamma mRNA than did the negative group. CONCLUSIONS: These results may indicate that IL-12 induces IFN-gamma expression and subsequent Th1 dominant condition in Japanese patients with sarcoidosis.


Assuntos
Regulação da Expressão Gênica , Interferon gama/biossíntese , Interleucina-12/farmacologia , Sarcoidose Pulmonar/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Lavagem Broncoalveolar , Técnicas de Cultura de Células , Feminino , Humanos , Interferon gama/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoidose Pulmonar/genética
20.
Invest Ophthalmol Vis Sci ; 40(9): 2130-40, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10440270

RESUMO

PURPOSE: To investigate the neuroprotective effects of brain-derived neurotrophic factor (BDNF) against potassium cyanide (KCN)-induced retinal damage. METHODS: Rats were injected intravitreally with iodinated BDNF. Two days later, eyeballs were dissected into various parts, and the level of radioactivity in each part was measured. Retinal damage was induced by incubating rat eyeballs with 5 mM KCN. BDNF was injected intravitreally 2 days before KCN treatment, and subsequent morphometric analysis was carried out to evaluate the retinal cell damage. To elucidate the mechanisms of BDNF's neuroprotective effects, the intravitreal concentrations of amino acids and the expression of calretinin were investigated. RESULTS: Intravitreally injected BDNF was distributed evenly throughout the eyes, and the incorporation of iodinated BDNF into the retina was three times higher than in other ocular tissues. Immunohistochemical analysis demonstrated that exogenous BDNF diffused throughout the retina and was especially concentrated in the inner (INL) and outer nuclear layer. Morphometric analysis showed that the number of INL cells of the posterior area, 880 microm from the optic nerve head, was 190 +/- 4 with KCN treatment and 284 +/- 9 in control animals. Cell death appeared to be necrotic. When eyes injected with either phosphate-buffered saline (PBS) or BDNF were subjected to treatment with KCN, the number of INL cells was 186 +/- 5 in the PBS-treated controls and 253 +/- 8 in eyes treated with BDNF. Also, BDNF increased the number of calretinin-positive cells in the INL and reduced the KCN-induced elevation of intravitreal glutamate levels. CONCLUSIONS: BDNF injected intravitreally reaches the retina and attenuates the INL cell death caused by KCN-induced metabolic insult. The neuroprotective effects of BDNF are partly ascribed to the upregulation of a calcium-binding protein and the attenuation of glutamate release into the vitreous body.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Morte Celular/efeitos dos fármacos , Hipóxia/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Retina/efeitos dos fármacos , Doenças Retinianas/prevenção & controle , Animais , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Calbindina 2 , Sobrevivência Celular , Proteínas do Olho/metabolismo , Técnica Indireta de Fluorescência para Anticorpo , Ácido Glutâmico/metabolismo , Hipóxia/induzido quimicamente , Hipóxia/metabolismo , Hipóxia/patologia , Marcação In Situ das Extremidades Cortadas , Masculino , Fármacos Neuroprotetores/metabolismo , Cianeto de Potássio , Coelhos , Ratos , Ratos Wistar , Retina/metabolismo , Retina/patologia , Doenças Retinianas/induzido quimicamente , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Proteína G de Ligação ao Cálcio S100/metabolismo
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