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1.
Int J Oral Maxillofac Surg ; 50(9): 1267-1270, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33648817

RESUMO

The aim of this study was to determine the hydraulic pressures necessary to separate and lift the sinus membrane from the sinus floor in order to ensure a more controlled and safer hydraulic transcrestal sinus lifting surgery and prevent sinus membrane perforation. A flow-regulating hydrodynamic device with a pressure sensor was used in nine patients. The hydraulic pressure was found to increase steadily up to a mean peak of 25.0±13.0kPa, which is comparable to the medium suction power of ordinary vacuum cleaners. Subsequently, there was a short plateau followed by a sharp decrease in the hydraulic pressure.


Assuntos
Levantamento do Assoalho do Seio Maxilar , Implantação Dentária Endóssea , Humanos , Maxila/cirurgia , Seio Maxilar/cirurgia , Mucosa Nasal
2.
Rev Sci Instrum ; 88(8): 083511, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28863699

RESUMO

The ITER vacuum ultra-violet (VUV) core survey spectrometer has been designed as a 5-channel spectral system so that the high spectral resolving power of 200-500 could be achieved in the wavelength range of 2.4-160 nm. To verify the design of the ITER VUV core survey spectrometer, a two-channel prototype spectrometer was developed. As a subsequent step of the prototype test, the prototype VUV spectrometer has been operated at KSTAR since the 2012 experimental campaign. From impurity injection experiments in the years 2015 and 2016, strong emission lines, such as Kr xxv 15.8 nm, Kr xxvi 17.9 nm, Ne vii 46.5 nm, Ne vi 40.2 nm, and an array of largely unresolved tungsten lines (14-32 nm) could be measured successfully, showing the typical photon number of 1013-1015 photons/cm2 s.

3.
Rev Sci Instrum ; 87(11): 11D840, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910454

RESUMO

We have developed a compact fast neutron camera based on a stack of nuclear emulsion plates and a pinhole collimator. The camera was installed at J-port of Korea superconducting tokamak advanced research at National Fusion Research Institute, Republic of Korea. Fast neutron images agreed better with calculated ones based on Monte Carlo neutron simulation using the uniform distribution of Deuterium-Deuterium (DD) neutron source in a torus of 40 cm radius.

4.
Rev Sci Instrum ; 85(11): 11E120, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430299

RESUMO

Two types of DD neutron energy spectrometer (NES) are under development for deuterium plasma operation in KSTAR to understand behavior of beam ions in the plasma. One is based on the state-of-the-art nuclear emulsion technique. The other is based on a coincidence detection of a recoiled proton and a scattered neutron caused by an elastic scattering of an incident DD neutron, which is called an associated particle coincidence counting-NES. The prototype NES systems were installed at J-port in KSTAR in 2012. During the 2012 and 2013 experimental campaigns, multiple shots-integrated neutron spectra were preliminarily obtained by the nuclear emulsion-based NES system.

5.
Rev Sci Instrum ; 85(11): 11E403, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430310

RESUMO

To optimize the design of ITER vacuum ultraviolet (VUV) spectrometer, a prototype VUV spectrometer was developed. The sensitivity calibration curve of the spectrometer was calculated from the mirror reflectivity, the grating efficiency, and the detector efficiency. The calibration curve was consistent with the calibration points derived in the experiment using the calibrated hollow cathode lamp. For the application of the prototype ITER VUV spectrometer, the prototype spectrometer was installed at KSTAR, and various impurity emission lines could be measured. By analyzing about 100 shots, strong positive correlation between the O VI and the C IV emission intensities could be found.

6.
Plant Dis ; 98(10): 1434, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30703952

RESUMO

In South Korea, the culture, production, and consumption of blueberry (Vaccinium corymbosum) have increased rapidly over the past 10 years. In June and July 2012, blueberry plants with leaf spots (~10% of disease incidence) were sampled from a blueberry orchard in Jinju, South Korea. Leaf symptoms included small (1 to 5 mm in diameter) brown spots that were circular to irregular in shape. The spots expanded and fused into irregularly shaped, large lesions with distinct dark, brownish-red borders. The leaves with severe infection dropped early. A fungus was recovered consistently from sections of surface-disinfested (1% NaOCl) symptomatic leaf tissue after transfer onto water agar and sub-culture on PDA at 25°C. Fungal colonies were dark olive and produced loose, aerial hyphae on the culture surfaces. Conidia, which had 3 to 6 transverse septa, 1 to 2 longitudinal septa, and sometimes also a few oblique septa, were pale brown to golden brown, ellipsoid to ovoid, obclavate to obpyriform, and 16 to 42 × 7 to 16 µm (n = 50). Conidiophores were pale to mid-brown, solitary or fasciculate, and 28 to 116 × 3 to 5 µm (n = 50). The species was placed in the Alternaria alternata group (1). To confirm the identity of the fungus, the complete internal transcribed spacer (ITS) rDNA region of a representative isolate, AAVC-01, was amplified using ITS1 and ITS4 primers (2). The DNA products were cloned into the pGEM-T Easy vector (Promega, Madison, WI) and the resulting pOR13 plasmid was sequenced using universal primers. The resulting 570-bp sequence was deposited in GenBank (Accession No. KJ636460). Comparison of ITS rDNA sequences with other Alternaria spp. using ClustalX showed ≥99% similarity with the sequences of A. alternata causing blight on Jatropha curcas (JQ660842) from Mexico and Cajannus cajan (JQ074093) from India, citrus black rot (AF404664) from South Africa, and other Alternaria species, including A. tenuissima (WAC13639) (3), A. lini (Y17071), and A. longipes (AF267137). Two base substitutions, C to T at positions 345 and 426, were found in the 570-bp amplicon. Phylogenetic analysis revealed that the present Alternaria sp. infecting blueberry grouped separately from A. tenuissima and A. alternata reported from other hosts. A representative isolate of the pathogen was used to inoculate V. corymbosum Northland leaves for pathogenicity testing. A conidial suspension (2 × 104 conidia/ml) from a single spore culture and 0.025% Tween was spot inoculated onto 30 leaves, ranging from recently emerged to oldest, of 2-year-old V. corymbosum Northland plants. Ten leaves were treated with sterilized distilled water and 0.025% Tween as a control. The plants were kept in a moist chamber with >90% relative humidity at 25°C for 48 h and then moved to a greenhouse. After 15 days, leaf spot symptoms similar to those observed in the field developed on the inoculated leaves, whereas the control plants remained asymptomatic. The causal fungus was re-isolated from the lesions of the inoculated plants to fulfill Koch's postulates. To our knowledge, this is the first report of Alternaria sp. on V. corymbosum in South Korea. References: (1) E. G. Simmons. Page 1797 in: Alternaria: An Identification Manual. CBS Fungal Biodiversity Centre, Utrecht, The Netherlands, 2007. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990. (3) M. P. You et al. Plant Dis. 98:423, 2014.

7.
Rev Sci Instrum ; 83(10): 10D303, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23126830

RESUMO

The neutron activation system (NAS) measures neutron fluence at the first wall and the total neutron flux from the ITER plasma, providing evaluation of the fusion power for all operational phases. The pneumatic transfer system (PTS) is one of the key components of the NAS for the proper operation of the system, playing a role of transferring encapsulated samples between the capsule loading machine, irradiation stations, counting stations, and disposal bin. For the validation and the optimization of the design, a prototype of the PTS was developed and capsule transfer tests were performed with the developed system.

8.
Rev Sci Instrum ; 81(10): 10E508, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21034036

RESUMO

A vacuum ultraviolet (VUV) spectrometer of a five-channel spectral system is designed for ITER main plasma impurity measurement. To develop and verify the system design, a two-channel prototype system is fabricated with No. 3 (14.4-31.8 nm) and No. 4 (29.0-60.0 nm) among the five channels. The optical system consists of a collimating mirror to collect the light from source to slit, two holographic diffraction gratings with toroidal geometry, and two different electronic detectors. For the test of the prototype system, a hollow cathode lamp is used as a light source. To find the appropriate detector for ITER VUV system, two kinds of detectors of the back-illuminated charge-coupled device and the microchannel plate electron multiplier are tested, and their performance has been investigated.

9.
Rev Sci Instrum ; 79(10): 10E505, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044490

RESUMO

A neutron activation system utilizing an encapsulated metal sample technique will be implemented to evaluate total fusion power from ITER plasma. The positions of seven irradiation ends for each poloidal section are determined to optimize the measurements from asymmetric, elongated plasma with minimum uncertainty. To determine the exact location of the irradiation end, some physical and technical aspects for each location are investigated. Monte Carlo neutronic calculations are performed to assess the physical characteristics and optimize the design of each irradiation end.

10.
Amino Acids ; 35(2): 339-43, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18163181

RESUMO

Down syndrome (DS) is the most common human chromosomal abnormality caused by an extra copy of chromosome 21. The phenotype of DS is thought to result from overexpression of a gene or genes located on the triplicated chromosome or chromosome region. Several reports have shown that the neuropathology of DS comprises developmental abnormalities and Alzheimer-like lesions such as senile plaques. A key component of senile plaques is amyloid beta-peptide which is generated from the amyloid precursor protein (APP) by sequential action of beta-secretases (BACE1 and BACE2) and gamma-secretase. While BACE1 maps to chromosome 11, APP and BACE2 are located on chromosome 21. To challenge the gene dosage effect and gain insight into the expressional relation between beta-secretases and APP in DS brain, we evaluated protein expression levels of BACE1, BACE2 and APP in fetal and adult DS brain compared to controls. In fetal brain, protein expression levels of BACE2 and APP were comparable between DS and controls. BACE1 was increased, but did not reach statistical significance. In adult brain, BACE1 and BACE2 were comparable between DS and controls, but APP was significantly increased. We conclude that APP overexpression seems to be absent during the development of DS brain up to 18-19 weeks of gestational age. However, its overexpression in adult DS brain could lead to disturbance of normal function of APP contributing to neurodegeneration. Comparable expression of BACE1 and BACE2 speaks against the hypothesis that increased beta-secretase results in (or even underlies) increased production of amyloidogenic A beta fragments. Furthermore, current data indicate that the DS phenotype cannot be fully explained by simple gene dosage effect.


Assuntos
Secretases da Proteína Precursora do Amiloide/biossíntese , Precursor de Proteína beta-Amiloide/biossíntese , Ácido Aspártico Endopeptidases/biossíntese , Córtex Cerebral/metabolismo , Síndrome de Down/metabolismo , Secretases da Proteína Precursora do Amiloide/análise , Precursor de Proteína beta-Amiloide/análise , Ácido Aspártico Endopeptidases/análise , Western Blotting , Córtex Cerebral/química , Córtex Cerebral/patologia , Síndrome de Down/patologia , Feminino , Feto , Humanos , Pessoa de Meia-Idade
11.
Appl Opt ; 45(27): 7131-6, 2006 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-16946793

RESUMO

A novel design of a Stark-tuned far-infrared laser using a circular hollow dielectric waveguide is proposed, and its characteristics are studied. Supplementary electrodes are inserted inside the circular hollow dielectric tube to suppress charge accumulation while keeping field uniformity. In what is believed to be a new design, the mode property is found to be improved, and the angular dependency of the attenuation loss according to the beam polarization is estimated to be much smaller than that of the conventional rectangular hybrid waveguide design. In this new design, DeltaM=0 far-infrared (FIR) transition as well as DeltaM=+/-1 transition can be observed, and the power enhancement for the DeltaM=0 FIR transition is expected.

12.
Amino Acids ; 26(3): 255-61, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15221505

RESUMO

Down Syndrome (DS, trisomy 21) is the most common genetic cause of mental retardation. The completed sequencing of genes encoded on chromosome 21 provides excellent basic information, however the molecular mechanisms leading to the phenotype of DS remain to be elucidated. Although overexpression of chromosome 21 encoded genes has been documented information at the protein expression level is mandatory as it is the proteins that carry out function. We therefore decided to evaluated expression level of seven proteins whose genes are encoded on chromosome 21: DSCR4, DSCR5, DSCR6; KIR4.2, GIRK2, KCNE1 and KCNE2 in fetal cortex brain of DS and controls at the early second trimester of pregnancy by Western blotting. beta-actin and neuron specific enolase (NSE) were used to normalise cell loss and neuronal loss. DSCR5 (PIG-P), a component of glycosylphosphatidylinositol- N-acetylglucosaminyltransferase (GPI-GnT), was overexpressed about twofold, even when levels were normalised with NSE. DSCR6 was overexpressed in addition but when normalised versus NSE, levels were comparable to controls. DSCR4 was not detectable in fetal brain. Potassium channels KIR4.2 and GIRK2 were comparable between DS and controls, whereas KCNE1 and KCNE2 were not detectable. Quantification of these proteins encoded on chromosome 21 revealed that not all gene products of the DS critical region are overexpressed in DS brain early in life, indicating that the DS phenotype cannot be simply explained by the gene dosage effect hypothesis. Overexpression of PIG-P (DSCR5) may lead to or represent impaired glycosylphosphatidylinositol- N-acetylglucosaminyltransferase mediated posttranslational modifications and subsequent anchoring of proteins to the plasma membrane.


Assuntos
Encéfalo/metabolismo , Cromossomos Humanos Par 21/genética , Síndrome de Down/genética , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Encéfalo/embriologia , Síndrome de Down/metabolismo , Feminino , Idade Gestacional , Hexosiltransferases , Humanos , Canais de Potássio/biossíntese , Canais de Potássio/genética , Gravidez , Proteínas da Gravidez/biossíntese , Proteínas da Gravidez/genética , RNA Longo não Codificante
13.
Amino Acids ; 25(1): 41-7, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12836057

RESUMO

Down syndrome (DS) is the most frequent genetic disorder with mental retardation and caused by trisomy 21. Although the molecular mechanisms of the various phenotypes of DS could be due to overexpression of gene(s) on chromosome 21, several groups have challenged this gene dosage effect hypothesis. The near completion of the sequencing of human chromosome 21 provides unprecedented opportunities to understand the molecular pathology of DS, however, functional information on gene products is limited so far. We therefore evaluated the levels of six proteins whose genes are encoded on chromosome 21 (trefoil factor 1, trefoil factor 2, trefoil factor 3, coxsackie virus and adenovirus receptor, carbonyl reductase 1 and interferon- alpha receptor) in fetal cerebral cortex from DS and controls at the early second trimester using Western blot analysis. None of the investigated proteins showed overexpression in DS compared to controls suggesting that these proteins are not involved in abnormal development of fetal DS brain and that DS phenotype can not be simply explained by the gene dosage effect hypothesis. We are systematically quantifying all proteins whose genes are encoded on chromosome 21 and these studies may provide a better understanding of genotype-phenotype correlation in DS.


Assuntos
Encéfalo/embriologia , Cromossomos Humanos Par 21/genética , Síndrome de Down/genética , Feto/fisiopatologia , Dosagem de Genes , Proteínas/genética , Encéfalo/fisiologia , Feminino , Idade Gestacional , Humanos , Gravidez , Proteínas/metabolismo , Fator Trefoil-2
14.
Amino Acids ; 24(1-2): 111-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12624742

RESUMO

Down syndrome (DS) is the most significant genetic disorder with mental retardation and is caused by trisomy 21. The phenotype of DS is thought to result from overexpression of a gene(s) located on the triplicated chromosome (region). An increasing body of evidence that challenge this "gene dosage effect" hypothesis, however, has been reported indicating that this hypothesis still remains to be elucidated. The availability of the complete sequence of genes on chromosome 21 could have an immediate impact on DS research, but no conclusions can be drawn from nucleic acid levels. This made us evaluate protein levels of six proteins, gene products, encoded on chromosome 21 (T-cell lymphoma invasion and metastasis inducing Tiam1 protein, holocarboxylase synthetase, human interferon-regulated resistance GTP-binding protein MxA, Pbx regulating protein 1, autoimmune regulator, and pericentrin) in fetal cortex from DS and controls at 18-19 weeks of gestational age using Western blot technique. None of the investigated proteins showed overexpression in DS compared to controls. Our present data showing unaltered expression of six proteins on chromosome 21 in fetal DS brain suggest that the existence of the trisomic state is not involved in abnormal development of fetal DS brain and that the gene dosage effect hypothesis is not sufficient to fully explain the DS phenotype. We are in the process of quantifying all gene products of chromosome 21 and our first results do not support the gene dosage hypothesis.


Assuntos
Encéfalo/metabolismo , Cromossomos Humanos Par 21 , Síndrome de Down/genética , Proteínas do Tecido Nervoso/genética , Western Blotting , Encéfalo/embriologia , Estudos de Casos e Controles , Feminino , Feto/metabolismo , Dosagem de Genes , Humanos
15.
Amino Acids ; 24(1-2): 119-25, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12624743

RESUMO

Down syndrome (DS) is the most common genetic cause of mental retardation. To explain the impact of extra chromosome 21 in the pathology of DS, gene dosage effect hypothesis has been proposed, but several investigators including our group have challenged this hypothesis. Although analysis of the sequence of chromosome 21 has been essentially completed, the molecular and biochemical mechanisms underlying the pathology are still unknown. We therefore investigated expression levels of six proteins encoded on chromosome 21 (HACS1, DYRK1A, alphaA-crystallin, FTCD, GARS-AIRS-GART, and CBS) in fetal cerebral cortex from DS and controls at 18-19 weeks of gestational age using Western blot analysis. Protein expression of HACS1 was significantly and remarkably decreased in DS, and the expression levels of five proteins were comparable between DS and controls suggesting that the gene dosage effect hypothesis is not sufficient to fully explain the DS phenotype. We are continuing to quantify proteins whose genes are encoded on chromosome 21 in order to provide a better understanding of the pathobiochemistry of DS at the protein level.


Assuntos
Encéfalo/metabolismo , Cromossomos Humanos Par 21 , Síndrome de Down/genética , Dosagem de Genes , Proteínas do Tecido Nervoso/genética , Western Blotting , Encéfalo/embriologia , Estudos de Casos e Controles , Feminino , Humanos
16.
Amino Acids ; 24(1-2): 127-34, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12624744

RESUMO

Down syndrome (DS) is the most frequent genetic disorder with mental retardation and caused by trisomy 21. Although the gene dosage effect hypothesis has been proposed to explain the impact of extra chromosome 21 on the pathology of DS, a series of evidence that challenge this hypothesis has been reported. The availability of the complete sequences of genes on chromosome 21 serves now as starting point to find functional information of the gene products, but information on gene products is limited so far. We therefore evaluated expression levels of six proteins whose genes are encoded on chromosome 21 (synaptojanin-1, chromosome 21 open reading frame 2, oligomycin sensitivity confering protein, peptide 19, cystatin B and adenosine deaminase RNA-specific 2) in fetal cerebral cortex from DS and controls at 18-19 weeks of gestational age using Western blot analysis. Synaptojanin-1 and C21orf2 were increased in DS, but others were comparable between DS and controls, suggesting that the DS phenotype cannot be simply explained by gene dosage effects. We are systematically quantifying all proteins whose genes are encoded on chromosome 21 in order to provide a better understanding of the pathobiochemistry of DS at the protein level. These studies are of significance as they show for the first time protein levels that are carrying out specific function in human fetal brain with DS.


Assuntos
Encéfalo/metabolismo , Cromossomos Humanos Par 21 , Síndrome de Down/genética , Dosagem de Genes , Western Blotting , Encéfalo/embriologia , Estudos de Casos e Controles , Feminino , Humanos
17.
J Neural Transm Suppl ; (67): 95-103, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15068242

RESUMO

Down syndrome (trisomy of chromosome 21) (DS) is the most common genetic cause of mental retardation. In our study we employed immunoblotting to evaluate protein expression of reduced folate carrier (hRFC), encoded by a gene localised on chromosome 21, in fetal DS brain. We observed increased expression of hRFC-immunoreactive band with an apparent MW of approximately 150 kDa, whereas the other bands (MWs approximately 60 and 50 kDa), were comparable to control. In conclusion, we suggest that aberrant hRFC expression may well have a role in the already observed deterioration of folate metabolism in DS. Moreover, no alterations of expression level of p53 and Sp1, supposed to play a role in the regulation of hRFC, suggest that regulation of hRFC expression in fetal life by these proteins is highly unlikely, at least by changes in their protein level.


Assuntos
Córtex Cerebral/metabolismo , Síndrome de Down/metabolismo , Feto/metabolismo , Ácido Fólico/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Membrana Transportadoras/biossíntese , Encéfalo/metabolismo , Síndrome de Down/genética , Feminino , Humanos , Proteínas de Membrana Transportadoras/genética , Proteína Carregadora de Folato Reduzido , Análise de Regressão , Estatísticas não Paramétricas
18.
J Neural Transm Suppl ; (67): 193-205, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15068251

RESUMO

There is a series of about 12 transcription factors expressed on chromosome 21. These transcription factors (TFs) are major candidates for playing a pathogenetic role for the abnormal wiring of the brain in fetal Down Syndrome (DS) as approximately 5,000 TFs are developmentally involved in the complex architecture of the human brain. TF derangement in DS has been already reported and we decided to contribute to the problem by studying four TFs encoded on chromosome 21 in fetal DS brain. We used fetal cortex of 8 DS fetuses and 6 controls (females) from the 18-19th week of gestation. Brain homogenates were subject to immunoblotting using goat-anti-BACH1, rabbit anti-heme oxygenase 1 (HO1), rabbit anti-ERG, rabbit anti-RUNX1 and goat anti-SIM2 l. Antibodies against beta-actin were used to normalise cell loss and antibodies against neuron-specific enolase were used to compensate neuronal loss. BACH1 was significantly overexpressed in fetal DS (p < 0.008) as compared to controls whereas RUNX1 and ERG proteins were comparable between groups, and SIM2 l was not detectable in any specimen. BACH1 was even significantly increased in the DS panel when normalised versus the housekeeping protein beta-actin (p < 0.01) or the neuron specific enolase (p < 0.01). HO-1 was found comparable between groups. BACH1, a member of the family of BTB-basic leucine zipper transcription factors, regulates gene expression through the NF-E2 site. More specifically, BACH1 suppresses expression of HO1. Increased BACH1, however, did not lead to decreased HO1, which would have explained oxidative stress observed in fetal DS.


Assuntos
Córtex Cerebral/metabolismo , Síndrome de Down/metabolismo , Feto/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição de Zíper de Leucina Básica , Síndrome de Down/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Humanos , Estatísticas não Paramétricas , Fatores de Transcrição/genética
19.
J Neural Transm Suppl ; (67): 225-34, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15068254

RESUMO

Fatty acid binding proteins (FABPs) are thought to play a role in the binding, targeting and transport of long-chain fatty acids, and at least three types of FABPs are found in human brain; heart type (H)-FABP, brain type (B)-FABP and epidermal type (E)-FABP. Although all three FABPs could be involved in normal brain function in prenatal and postnatal life, a neurobiological role of FABPs in neurodegenerative diseases has not been reported yet. These made us evaluate the protein levels of FABPs in brains from patients with Down syndrome (DS) and Alzheimer's disease (AD) and fetal cerebral cortex with DS using two-dimensional (2-D) gel electrophoresis with subsequent matrix-assisted laser desorption ionization mass spectroscopy (MALDI-MS) identification and specific software for quantification of proteins. In adult brain, B-FABP was significantly increased in occipital cortex of DS, and H-FABP was significantly decreased in DS (frontal, occipital and parietal cortices) and AD (frontal, temporal, occipital and parietal cortices). In fetal brain, B-FABP and epidermal E-FABP levels were comparable in controls and DS. We conclude that aberrant expression of FABPs, especially H-FABP may alter membrane fluidity and signal transduction, and consequently could be involved in cellular dysfunction in neurodegenerative disorders.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Síndrome de Down/metabolismo , Ácidos Graxos/metabolismo , Miocárdio , Proteínas Supressoras de Tumor , Adulto , Idoso , Doença de Alzheimer/genética , Proteínas de Transporte/classificação , Proteínas de Transporte/genética , Síndrome de Down/genética , Proteína 3 Ligante de Ácido Graxo , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Humanos , Pessoa de Meia-Idade , Miocárdio/metabolismo , Estatísticas não Paramétricas
20.
Endocrine ; 15(1): 131-6, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11572319

RESUMO

In a previous study, we clearly demonstrated that an application of gonadotropin-releasing hormone (GnRH) to cultured rat pituitary cells increased the expression of GnRH receptor (GnRH-R) mRNA through transcriptional activation of GnRH-R gene rather than suppression of the turnover rate of GnRH-R mRNA. Along with GnRH, gonadal steroids seem to be an important regulator for GnRH-R expression in the pituitary gland. Recent in vivo studies reported that an application of gonadal steroids to gonadectomized animals modulated GnRH-R mRNA expression in the pituitary gland. However, it has not been clearly understood whether steroids may act directly at the pituitary or indirectly via modulation of hypothalamic GnRH release. Therefore, we assessed the effects of estrogen and progesterone on GnRH-R mRNA expression in primary cultured female rat pituitary cells. Neither estradiol nor progesterone modulates the basal expression of GnRH-R mRNA in primary cultured pituitary cells. When cultured pituitary cells were exposed to different doses of estradiol in combination with GnRH (0.2 nM), the GnRH-stimulated increment of GnRH-R mRNA expression was not significantly changed by estradiol at any given doses. However, when different doses of progesterone were added to primary cultured pituitary cells in combination with GnRH (0.2 nM), GnRH-induced increases in GnRH-R mRNA levels were reduced in a dose-related manner, showing a significant reduction at 100 nM progesterone. Furthermore, the addition of estradiol reinforced the suppressive effect of progesterone on the homologous upregulation of GnRH-R mRNA expression. Collectively, our results clearly demonstrated that progesterone directly attenuates the homologous upregulation of GnRH-R mRNA expression at the pituitary level, and that estradiol potentiates the effect of progesterone.


Assuntos
Estradiol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Adeno-Hipófise/metabolismo , Progesterona/farmacologia , Receptores LHRH/genética , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Estradiol/administração & dosagem , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/farmacologia , Progesterona/administração & dosagem , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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