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1.
Emerg Infect Dis ; 29(12): 2587-2589, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37987598

RESUMO

We diagnosed Mycobacterium tuberculosis in captive lemurs and a fossa in Antananarivo, Madagascar. We noted clinical signs in the animals and found characteristic lesions during necropsy. The source of infection remains unknown. Our results illustrate the potential for reverse zoonotic infections and intraspecies transmission of tuberculosis in captive wildlife.


Assuntos
Lemur , Mycobacterium tuberculosis , Tuberculose , Animais , Madagáscar/epidemiologia , Tuberculose/veterinária , Animais Selvagens , Animais de Zoológico
2.
Rev Sci Instrum ; 92(4): 043556, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243487

RESUMO

An incoherent Thomson scattering diagnostic will be installed in the JT-60SA tokamak to measure electron temperature and electron density profiles. The target radial spatial resolution is 25 mm with 46 spatial channels. The accuracy in electron temperature and density is a few percent at ne = 7.5 × 1019 m-3, which is the expected value in the plasma core. This paper presents the designs of collection optics, fibers with their alignment system, and polychromators. The collection optics overcomes unique issues for superconducting fusion devices, i.e., limited design space, high-temperature measurements, and harsh radiation condition. When in several years the more performing plasma will generate intense nuclear radiation, the lens materials of the optics can be replaced by radiation resistant glasses without major changes in the lens holder. It will prevent transmission degradation and keep stable measurement accuracy.

3.
Rev Sci Instrum ; 87(9): 093502, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27782603

RESUMO

This paper evaluates the accuracy of electron temperature measurements and relative transmissivities of double-pass Thomson scattering diagnostics. The electron temperature (Te) is obtained from the ratio of signals from a double-pass scattering system, then relative transmissivities are calculated from the measured Te and intensity of the signals. How accurate the values are depends on the electron temperature (Te) and scattering angle (θ), and therefore the accuracy of the values was evaluated experimentally using the Large Helical Device (LHD) and the Tokyo spherical tokamak-2 (TST-2). Analyzing the data from the TST-2 indicates that a high Te and a large scattering angle (θ) yield accurate values. Indeed, the errors for scattering angle θ = 135° are approximately half of those for θ = 115°. The method of determining the Te in a wide Te range spanning over two orders of magnitude (0.01-1.5 keV) was validated using the experimental results of the LHD and TST-2. A simple method to provide relative transmissivities, which include inputs from collection optics, vacuum window, optical fibers, and polychromators, is also presented. The relative errors were less than approximately 10%. Numerical simulations also indicate that the Te measurements are valid under harsh radiation conditions. This method to obtain Te can be considered for the design of Thomson scattering systems where there is high-performance plasma that generates harsh radiation environments.

4.
Biochim Biophys Acta ; 1487(2-3): 255-67, 2000 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-11018477

RESUMO

Male WBN/Kob rats derived from the Wistar strain spontaneously develop chronic pancreatitis as late as 3 months old. To assess the degree of disease severity, we compared the lipolytic enzyme levels in pancreas of 2-, 4-, and 6-month-old WBN/Kob rats fed isocaloric no fat (NF) and high fat (HF, 57% of total calories) diets and its pathology. Diet treatment did not significantly affect lipase and group Ib phospholipase A(2) (PLA(2)) levels in the pancreas at all ages. Development of chronic pancreatitis at the age of 4 and 6 months was consistent with the tendency of decreasing group Ib PLA(2) specific content determined by enzyme immunoassay and lipase activity, and the decreased number of group Ib PLA(2)-positive acinar cells. Pancreatic lipase and group Ib PLA(2) levels of 4-month-old WBN/Kob rats were significantly lower than those of control Wistar rats at age 4 months irrespective of diet. This allowed us to adopt 4-month-old WBN/Kob rats as a model of pancreatic insufficiency, which could be a useful tool to examine the role of gastrointestinal enzymes in lipid digestion. Ca(2+)-independent PLA(2) activity of brush border membrane-associated phospholipase B/lipase (PLB/LIP) in ileal mucosa increased significantly in 4-month-old WBN/Kob rats while its content and transcript levels remained constant, suggesting its activation at the enzyme level. In WBN/Kob rats fed the HF diet at age 4 months, PLA(2) activity catalyzed by PLB/LIP in the proximal ileal mucosa was four times the total PLA(2) activity in the intestinal lumen. These results indicate that PLB/LIP compensates for the depletion of pancreatic lipolytic enzymes in WBN/Kob rats with pancreas insufficiency.


Assuntos
Sistema Digestório/enzimologia , Insuficiência Pancreática Exócrina/enzimologia , Mucosa Intestinal/enzimologia , Lisofosfolipase/metabolismo , Fosfolipases A/metabolismo , Fatores Etários , Amilases/análise , Animais , Peso Corporal , Catálise , Dieta com Restrição de Gorduras , Gorduras na Dieta/administração & dosagem , Insuficiência Pancreática Exócrina/complicações , Fezes/enzimologia , Lipase/análise , Lipólise , Masculino , Pâncreas/enzimologia , Pancreatite/etiologia , Fosfolipases A/análise , Ratos , Ratos Wistar , Triglicerídeos/análise
5.
Biochim Biophys Acta ; 1170(2): 125-30, 1993 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-8399335

RESUMO

We purified a phospholipase A2 (PLA2) from human ileal mucosa to homogeneity. Its NH2-terminal amino acid sequence, amino acid composition, molecular weight, and elution behavior on reverse phase high-performance liquid chromatography were identical to those of human group II PLA2 purified from synovial fluid or spleen. The ileal PLA2 preferred anionic phosphatidylglycerol as substrate. On immunoblot analysis, human ileal mucosa gave more intense immunoreactivity with anti-human synovial fluid PLA2 antibody, at the same position as the purified enzyme, than the cecal mucosa. Northern blot analysis also showed that the level of group II PLA2 mRNA in the ileal mucosa was greater than that in the cecal mucosa. The enzyme was rather uniformly distributed over the colonic mucosa, from cecum to sigmoid colon. These results indicate that the ileal mucosa contains group II PLA2, and that its expression in the ileal mucosa was higher than that in the colonic mucosa.


Assuntos
Íleo/enzimologia , Mucosa Intestinal/enzimologia , Fosfolipases A/isolamento & purificação , Sequência de Aminoácidos , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão , Colo/enzimologia , Doença de Crohn/sangue , Doença de Crohn/enzimologia , Humanos , Dados de Sequência Molecular , Peso Molecular , Fosfatidilgliceróis/metabolismo , Fosfolipases A/química , Fosfolipases A2
6.
Biochim Biophys Acta ; 1316(3): 183-90, 1996 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-8781537

RESUMO

We measured calcium-dependent phospholipase A2 (PLA2) activity and immunoreactive group II PLA2 levels of 54 normal discs obtained from cadavers and 73 disc samples surgically obtained from patients with spinal disorders, including intervertebral disc herniations, spondylosis, and spondylolisthesis. Both cadaveric and surgical disc specimens contained about two-fold greater PLA2 activity than the ileal mucosa, one of the richest sources of group II PLA2. Discs of middle-aged cases had significantly higher activity than those of younger and elder cases. In cadaveric normal discs, calcium-dependent PLA2 activity was significantly higher in females than in males. Annulus fibrosus and nucleus pulposus contained the same PLA2 levels. In diseased disc, herniated fragments that had extruded or protruded out of the discs possessed lower activity than other parts of discs in the intervertebral space. Immunoreactive group II PLA2 levels of intervertebral discs closely correlated with PLA2 enzymatic activity. We purified a PLA2 from human intervertebral disc to homogeneity to further identify the isozymic nature of discal PLA2. Its NH2-terminal amino acid sequences and molecular weight were identical to those of human group II PLA2. Immunohistochemical analysis using a monoclonal anti-group II PLA2 antibody showed that in both annulus fibrosus and nucleus pulposus chondrocytes contained intense group II PLA2 immunoreactivity in their cytoplasm, and that the matrix contained no substantial immunoreactivity. These results suggest that group II PLA2 in chondrocytes has important physiological roles in discal ordinary metabolism, maintaining discal homeostasis.


Assuntos
Disco Intervertebral/enzimologia , Fosfolipases A/metabolismo , Doenças da Coluna Vertebral/enzimologia , Adolescente , Adulto , Fatores Etários , Idoso , Sequência de Aminoácidos , Anticorpos Monoclonais , Criança , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fosfolipases A/imunologia , Fosfolipases A2
7.
Biochim Biophys Acta ; 1300(1): 1-4, 1996 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-8608155

RESUMO

From the Tn5-inserted mutant library of Vibrio cholerae O1, we found a mutant, NF404, which lost the production of both hemolysin and cholera toxin (CT) even though the Tn5-insertion site was out side from the structural genes for hemolysin and CT. Cloning and sequencing analysis of the homologous region from the wild-type strain, revealed that the sequence spanning the coding region of an ORF1 nominated as lypA, encoding a 39.5 kDa protein. Deduced amino acid sequence of the lypA gene had 37.6% identity to the lysophospholipase L2 (EC 3.1.1.5) of Escherichia coli. In the downstream of lypA, a second open reading frame (ORF2) encoding an unknown protein with molecular weight of 19.9 kDa was found. Assaying the lysophospholipase L2 activity in the cell extract of E.coli harboring lypA in an expression vector showed clear increase in the enzymatic activity.


Assuntos
Genes Bacterianos , Lisofosfolipase/genética , Vibrio cholerae/genética , Sequência de Aminoácidos , Sequência de Bases , Toxina da Cólera/biossíntese , Cromossomos Bacterianos , Proteínas Hemolisinas/biossíntese , Dados de Sequência Molecular , Fases de Leitura Aberta , Homologia de Sequência de Aminoácidos , Vibrio cholerae/enzimologia
8.
Biochim Biophys Acta ; 1352(2): 151-5, 1997 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-9199245

RESUMO

The complete open reading frame (ORF) of the c-kit cDNA was cloned from a cerebellar cDNA library of the Shiba goat (Capra hircus var Shiba) with the dominant black-eyed white phenotype. The analysis of the deduced amino acid sequence revealed the presence of a single amino acid insertion (alanine) in the kinase insert (KI) region. While the newly found alanine insertion is not correlated with the coat color phenotype of goats, it appears to be characteristic of the c-kit genes in goats and sheep. Although the biological significance of the insert remains to be investigated, its phylogenetically limited distribution will provide us with a useful and interesting tool to analyze the problems of evolution of sheep and goats in bovidae.


Assuntos
Alanina/análise , DNA Complementar/genética , Cabras/genética , Proteínas Proto-Oncogênicas c-kit/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Evolução Biológica , Clonagem Molecular , Dados de Sequência Molecular , Fenótipo , Alinhamento de Sequência , Ovinos
9.
Biochim Biophys Acta ; 1447(2-3): 199-207, 1999 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-10542316

RESUMO

Using a differential hybridization method, we have cloned a zinc finger transcription factor gene whose expression was enhanced by adipogenic hormones in preadipocyte 3T3-L1 cells. Cloning of this gene revealed that it encodes a mouse homologue of rat Zf9 and human CPBP/GBF, previously identified as a wound-induced transcription factor and GC-rich binding protein, respectively. The mRNA for this clone consisted of 0.9 kb coding region and 3.2 kb long 3' untranslated region. Northern blot analysis revealed that it was ubiquitously expressed, among adult tissues, in which abundant expression was observed in lung, ovary and thymus. The transcript was transiently induced by different stimuli such as serum, cAMP and 12-O-tetradecanoylphorbol 13-acetate. Nuclear run-on and RNA synthesis inhibitor chase experiments indicated that the transient induction of the mRNA was regulated both at transcriptional and post-transcriptional levels.


Assuntos
Adipócitos/fisiologia , Proteínas Proto-Oncogênicas , Transativadores/genética , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Humanos , Fator 6 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like , Camundongos , Dados de Sequência Molecular , Ratos , Homologia de Sequência , Dedos de Zinco
10.
Biochim Biophys Acta ; 1007(1): 124-6, 1989 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-2909239

RESUMO

The content of mRNA for a pancreatic-type phospholipase A2 present in rat gastric mucosa was much greater than that in pancreas. In lung the mRNA for this pancreatic-type phospholipase A2 was also detected, but less than in pancreas. Nucleotide sequence analysis showed that these pancreatic-type phospholipase A2 cDNAs derived from rat gastric mucosa and lung were completely identical to that from rat pancreas (Ohara et al. (1986) J. Biochem. 99, 733-739). This demonstrates that the pancreatic-type phospholipase A2 present in gastric mucosa and lung does not originate from pancreas.


Assuntos
Mucosa Gástrica/análise , Pulmão/análise , Fosfolipases A/análise , Fosfolipases/análise , RNA Mensageiro/análise , Animais , Sequência de Bases , Northern Blotting , Clonagem Molecular , DNA , Sondas de DNA , Dados de Sequência Molecular , Fosfolipases A/genética , Fosfolipases A/fisiologia , Fosfolipases A2 , Ratos
11.
Biochim Biophys Acta ; 1226(2): 201-5, 1994 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-8204668

RESUMO

Enzyme activity, protein contents, and mRNA contents of group II phospholipase A2 (PLA2) in hepatocellular carcinoma (HCC) surgically obtained from 8 patients were compared with those in either its neighboring liver tissues or control liver tissues. The PLA2 specific activity towards the mixed micelles of 1-palmitoyl-2-oleoyl-phosphatidylglycerol and cholate was significantly greater in the tumor tissues (6.62 +/- 1.46 nmol/min/mg) than those in the surrounding liver tissues (1.33 +/- 0.22 nmol/min/mg) and controls (0.43 +/- 0.04 nmol/min/mg). The results of immunoblot analysis using a specific anti-human group II PLA2 antibody and of Northern blot analysis using a human group II PLA2 cDNA as a probe demonstrated that group II PLA2 was responsible for the increased enzyme activity. The contents of immunoreactive group II PLA2 in the tumor tissues (8.81 +/- 1.24 ng/mg) were significantly higher than those in the surrounding liver tissues (1.74 +/- 0.27 ng/mg); those in the control tissues were below the analytical range of the method used. The group II PLA2 mRNA was also significantly increased in the tumor tissues, compared with that in the surrounding liver tissues, whereas it was not detectable in the controls. This indicates that group II PLA2 in HCC is induced at the pretranslational level.


Assuntos
Carcinoma Hepatocelular/enzimologia , Neoplasias Hepáticas/enzimologia , Fosfolipases A/genética , Expressão Gênica , Humanos , Fígado/enzimologia , Fosfolipases A2 , RNA Mensageiro/análise
12.
Biochim Biophys Acta ; 1345(1): 99-108, 1997 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-9084507

RESUMO

The proliferation of mesangial cells plays a central role in the progression of glomerulonephritis. We studied the role of group II phospholipase A2 in interleukin-1-stimulated proliferation of mesangial cells. Cultured rat mesangial cells secreted 5.3 units group II phospholipase A2/24 h per 10(5) cells in response to stimulation of 200 U/ml of interleukin-1. Northern hybridization analysis showed that mRNA for group II phospholipase A2 was induced by exogenously added group II phospholipase A2 (15 U/ml) as well as interleukin-1. The pretreatment of quiescent mesangial cells with interleukin-1 augmented [3H]thymidine incorporation caused by platelet derived growth factor. Exogenous group II phospholipase A2 (5-36 U/ml) purified homogeneously from rat spleen also increased [3H]thymidine incorporation by platelet derived growth factor-stimulated mesangial cells in a dose dependent manner (36 U/ml phospholipase A2; 1.9-fold). The stimulatory effect of interleukin-1 on DNA synthesis of mesangial cells was specifically blunted by immunoglobulin raised against group II phospholipase A2. Group II phospholipase A2 (16 U/ml) amplified a platelet derived growth factor-stimulated increase in the mesangial cell number by 1.5-fold. Among the products of the phospholipase A2-catalyzed reaction, lysophospholipids including lysophosphatidylcholine, lysophosphatidylethanolamine and lysophosphatidic acid, but not fatty acids, mimicked the stimulatory effect of interleukin-1 and phospholipase A2. These results suggest that group II phospholipase A2 acts as a signaling molecule that mediates interleukin-1-induced growth of rat mesangial cells through yielding lysophospholipids.


Assuntos
Mesângio Glomerular/efeitos dos fármacos , Substâncias de Crescimento/análise , Interleucina-1/farmacologia , Fosfolipases A/análise , Animais , Contagem de Células , Divisão Celular , Células Cultivadas/efeitos dos fármacos , DNA/biossíntese , Mesângio Glomerular/enzimologia , Fosfolipases A2 do Grupo II , Lisofosfolipídeos/análise , Fosfolipases A/genética , Fosfolipases A/farmacologia , Fosfolipases A2 , Fator de Crescimento Derivado de Plaquetas/farmacologia , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley
13.
Int J Dev Biol ; 42(8): 1143-51, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9879712

RESUMO

With the aim of identifying the gene(s) located downstream from SRY, we transfected an ES cell line with XX karyotype, TMA-18, with a Sry DNA construct and established cell lines, TS18-1 and TS18-2, where the transfected Sry was expressed in the functional linear mRNA form. Among the five potential SRY-target genes examined, i.e., MIS, SF1, P450arom, Sox9 and WT1, only the expression of WT1 was induced de novo by the unscheduled expression of Sry in the transfected cell lines. No clear indication of Sry-induced enhancement of Sox9 expression was obtained in the present series of experiments. Function of a yet unidentified gene(s) located on the Y chromosome might be needed for the up-regulation of Sox 9 expression which takes place during the development of male gonads. Quantitative RT-PCR analysis of the patterns of WT1 expression in developing fetal gonads revealed that although both male and female fetal gonads express WT1, male gonads invariably expressed WT1 mRNA at higher levels than female ones after the Sry expression. Immunohistochemical analysis of the male fetal gonads between 10.5 and 13.5 dpc demonstrated the presence of strong WT1 immunoreactivity in Sertoli cells of the primordial testes. Suggestions were made in the past indicating that both SF1 and WT1 proteins might be active in a common pathway upstream from Sry. Our results showed that WT1 is located downstream, rather than upstream from Sry and behaves independently from SF1. Analysis using an appropriate in vitro system will be essential to understand the molecular mechanisms of SRY action within cells.


Assuntos
Proteínas de Ligação a DNA/genética , Embrião de Mamíferos/citologia , Expressão Gênica , Proteínas Nucleares , Células-Tronco/metabolismo , Fatores de Transcrição/genética , Transfecção , Animais , Western Blotting , Linhagem Celular , Proteínas de Ligação a DNA/análise , Feminino , Gônadas/embriologia , Gônadas/metabolismo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos ICR , RNA Mensageiro/metabolismo , Proteína da Região Y Determinante do Sexo , Fatores de Transcrição/análise , Proteínas WT1
14.
FEBS Lett ; 449(2-3): 273-6, 1999 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-10338147

RESUMO

The expression of the cellular protooncogene c-ski was examined in the rat uterus. In situ hybridization revealed that c-ski mRNA was expressed in the uterus of the adult rat on the day of estrous and localized mainly in the luminal and glandular epithelia. To test the possibility that the expression of c-ski mRNA is induced by estrogen, rats were ovariectomized and estradiol-17beta (E2) was injected. The expression of c-ski mRNA was upregulated 3 h after E2 treatment, reaching the highest level at 6 h and this persisted until 24 h; the E2-induced expression of c-ski mRNA was restricted to the luminal and glandular epithelia. These results suggest that the c-ski gene plays a role in uterine epithelial cell proliferation and mediates the proliferative action of E2.


Assuntos
Proteínas de Ligação a DNA/genética , Endométrio/metabolismo , Estradiol/metabolismo , Regulação da Expressão Gênica , Proteínas Proto-Oncogênicas/genética , Animais , Divisão Celular , Proteínas de Ligação a DNA/metabolismo , Endométrio/citologia , Células Epiteliais/metabolismo , Estradiol/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Ovariectomia , Proteínas Proto-Oncogênicas/metabolismo , Proto-Oncogenes , Ratos , Ratos Wistar , Útero/metabolismo
15.
FEBS Lett ; 370(1-2): 141-5, 1995 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-7649292

RESUMO

Group II phospholipase A2 (PLA2) is a mediator of inflammation in various disease including glomerulonephritis. We recently found that urinary excretion of PLA2 was increased in patients with mesangial proliferative glomerulonephritis and that interleukin-1 (IL-1) enhanced platelet derived growth factor-stimulated mesangial cell proliferation through the action of group II PLA2 secreted in response to IL-1 stimuli. Here we report signal transducing mechanism through group II PLA2 in mesangial cells. Group II PLA2 (1-15 U/ml) rapidly activated mitogen-activated protein (MAP) kinase. IL-1 beta activated MAP kinase in two phases and the slow activation in the late phase, proceeding in parallel with increased group II PLA2 secretion elicited by IL-1 treatment, was inhibited by the specific antibody raised against group II PLA2. This suggests that the late phase activation of IL-1-induced MAP kinase was mediated, at least in part, by secreted group II PLA2.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Mesângio Glomerular/enzimologia , Fosfolipases A/metabolismo , Animais , Anticorpos/farmacologia , Células Cultivadas , Citosol/enzimologia , Ativação Enzimática , Humanos , Interleucina-1/farmacologia , Cinética , Fosfolipases A/imunologia , Fosfolipases A2 , Ratos , Proteínas Recombinantes/farmacologia , Fatores de Tempo
16.
FEBS Lett ; 304(1): 69-72, 1992 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-1618301

RESUMO

Previously, we reported the presence of group II-like phospholipase A2 activity in the soluble fraction of rat gingiva. In the present study, we found that treatment of rat gingival cells with human recombinant interleukin-1 beta resulted in dose-dependent stimulation of intracellular and extracellular phospholipase A2 activity. Antisera against group II phospholipase A2 totally blocked the interleukin-1 beta-induced phospholipase A2 activity, but antisera against group I phospholipase A2 did not. Moreover, immunoblot analysis showed that the induced phospholipase A2 was group II phospholipase A2. These findings suggest that the induced enzyme belongs to the group II phospholipase A2 family of proinflammatory enzymes.


Assuntos
Gengiva/enzimologia , Interleucina-1/fisiologia , Fosfolipases A/biossíntese , Animais , Células Cultivadas , Indução Enzimática , Fibroblastos/enzimologia , Gengiva/citologia , Immunoblotting , Cinética , Masculino , Fosfolipases A2 , Ratos , Ratos Endogâmicos
17.
Neuroscience ; 71(1): 221-30, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8834404

RESUMO

We replaced the mouse neurotrophin-3 gene with the Escherichia coli-derived lacZ gene by means of homologous recombination. The mice with this mutation were useful models for studying the distribution of neurotrophin-3 expression in vivo, because visualization by 5-bromo-4-chloro-3-indoyl-beta-D-galactopyranoside (X-Gal) staining was simple and rapid compared with in situ hybridization or immunohistochemistry. Whole-mount staining of mutant embryos at embryonic day 10 revealed that lacZ, a reporter for the neurotrophin-3 gene, was expressed in the mesencephalon, mandibular arch and somites. In the embryos at days 13-17, lacZ was markedly expressed in the peripheral target tissues of sensory and sympathetic neurons. We also found that spinal motor neurons and sensory neurons in trigeminal and dorsal root ganglia express lacZ. Some of these X-Gal staining regions overlapped with the sites expressing trkC, a high-affinity receptor for neurotrophin-3. The distribution of X-Gal staining in heterozygotes and homozygotes was similar to that of neurotrophin-3 messenger RNA detected by in situ hybridization. However, there was less lacZ expression in the dorsal root ganglia of homozygotes than neurotrophin-3 expression in wild-type mice. These results suggest that the neurotrophin-3 produced in the dorsal root ganglia also plays a role in the survival of some of the neurotrophin-3-positive neurons and that the local mode of neurotrophic activity is widely distributed.


Assuntos
Expressão Gênica/fisiologia , Genes Reporter/fisiologia , Óperon Lac/fisiologia , Fatores de Crescimento Neural/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Química Encefálica/genética , Química Encefálica/fisiologia , Feminino , Galactosídeos , Gânglios Espinais/citologia , Gânglios Espinais/embriologia , Gânglios Espinais/metabolismo , Genes Reporter/genética , Imuno-Histoquímica , Indóis , Óperon Lac/genética , Camundongos , Camundongos Mutantes Neurológicos , Dados de Sequência Molecular , Fatores de Crescimento Neural/fisiologia , Neurotrofina 3 , Nervos Periféricos/citologia , Nervos Periféricos/embriologia , Nervos Periféricos/metabolismo , Gravidez , Ratos , beta-Galactosidase/genética
18.
Placenta ; 25(10): 810-9, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15451196

RESUMO

Matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) play key roles during the placentation of highly invasive haemochorial type. Our knowledge is yet scanty, however, regarding the roles played by MMPs and TIMPs in the placentation of non-invasive synepitheliochorial type. In the present study, expression patterns of MT1-MMP, MMP-2 and TIMP-2 mRNAs as well as the encoded proteins in the endometrium and the placenta were examined on Days 35, 75, and 100 of pregnancy, representing roughly the 1st, 2nd and 3rd trimesters of caprine gestation, by means of quantitative RT-PCR analysis, in situ hybridization, immunoblotting, gelatin zymography and immunohistochemistry. In the endometrium and the intercotyledonal trophoblast, the expression levels of the 3 genes remained relatively uniform throughout the period of gestation examined. Curiously, however, in the placentomes, the relative expression levels of MT1-MMP mRNA increased linearly from Day 35 to Day 100, while those of MMP-2 and TIMP-2 were clearly down-regulated in Day 100 placentae. The expression levels of MT1-MMP and TIMP-2 proteins in placentomes were well correlated with those of the respective mRNAs. In the case of MMP-2, the total amount of MMP-2 protein (the combined values of the latent, the intermediate and the active forms) decreased slightly, while the levels of the active form increased markedly from Day 35 to Day 100. Immunohistochemical analysis of the placentome revealed that MT1-MMP and TIMP-2 proteins were co-localized in the binucleate trophoblast cells; expression of these 2 proteins was not detected in the uninuclear principal trophoblast cells. MMP-2 expression was detected both in the binucleate and in the uninuclear principal cells of the trophoblast and in the endometrial stromal cells of the uterine septum, regardless of the stages of gestation examined. The co-localization of MT1-MMP, MMP-2 and TIMP-2 in binucleate trophoblast cells, the cotyledonal trophoblast cells and the subsyncytial stromal cells is likely to reflect the functional coordination of the 3 proteins in these cells during trophoblastic invasion and the placental tissue remodeling in the placentome.


Assuntos
Cabras , Metaloproteinase 2 da Matriz/genética , Metaloendopeptidases/genética , Placenta/enzimologia , Prenhez/fisiologia , Inibidor Tecidual de Metaloproteinase-2/genética , Animais , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Idade Gestacional , Hibridização In Situ , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/metabolismo , Placenta/anatomia & histologia , Placentação/fisiologia , Gravidez , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Trofoblastos/citologia , Trofoblastos/enzimologia
19.
Placenta ; 17(8): 583-90, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8916206

RESUMO

The outgrowth of the mouse blastocyst in culture represents an in vitro model of trophoblastic invasion. In the present study we analysed trophoblast spreading by time lapse video microscopy. Trophoblast spreading consists of (1) the migration and (2) the giant cell transformation of trophoblast cells, (3) the proliferation of ectoplacental cone (EPC) cells and (4) the subsequent transformation of EPC cells into the secondary giant cells. During migration, ruffling of the trophoblast cell membrane is followed by the formation of lamellipodia. The mean surface areas of the spreading trophoblast, measured in more than 100 cultured blastocysts, increased linearly from 48 to 96 h of culture, while the linear migratory speed at the periphery of the outgrowth declined as the time of culture advanced. The EPC cells increased in size approximately eightfold during the giant cell transformation. The apparent nuclear:cytoplasmic ratios, i.e., ratios between the size of nucleus and that of the cytoplasm, measured as the surface areas on the photomicrographs, of EPC cells increased between 40-46 h of culture, but a sharp decline in the ratio occurred between 50 and 51 h of culture, reflecting either the sudden and tremendous increase in the cellular volume and/or spreading of the cytoplasm. The rates of trophoblast spreading varied considerably among the blastocysts of different genetic constitution examined (ICR, C57BL/6, C3H/He and (B6 x C3)F1. It was fastest in blastocysts obtained from matings of males and females of (B6 x C3)F1, and slowest in the C57BL/6 embryos. The differences in the rate of outgrowth observed may not simply be ascribed to difference in the developmental speed of the early embryos, because the rate of outgrowth reached a plateau at about 96-120 h and no "catch-up' was observed by leaving the blastocysts in culture longer. Our results strongly suggest the possible presence of genetic regulatory mechanisms underlying trophoblast outgrowth; further analysis of the phenomenon may provide clues to understand the molecular mechanisms of trophoblastic invasion during the early phase of implantation, hopefully leading to improved success rates of in vitro fertilization-embryo transfer.


Assuntos
Trofoblastos/fisiologia , Animais , Blastocisto/fisiologia , Núcleo Celular/ultraestrutura , Meios de Cultura , Citoplasma/ultraestrutura , Feminino , Células Gigantes/fisiologia , Células Gigantes/ultraestrutura , Cinética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Gravidez , Especificidade da Espécie , Trofoblastos/ultraestrutura , Gravação em Vídeo
20.
Placenta ; 19(1): 41-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9481784

RESUMO

Membrane type matrix metalloproteinases (MT-MMPs) possess a C-terminal transmembrane domain and are expressed on the cell membrane. It was suspected, therefore, that MT1-MMP might play an important role in the trophoblastic invasion during implantation. The patterns of expression and localization of membrane type matrix metalloproteinase-1 (MT1-MMP) were examined immunocytochemically in cultured mouse blastocysts and excised extoplacental cones (EPCs). MT1-MMP immuno-reactivity was present in the giant trophoblast cells located at the periphery of the spreading trophoblast of cultured blastocysts and the outgrowths of cultured EPCs, but not in the densely packed trophoblast cells in both the blastocysts and the EPCs. It appears likely that MT1-MMP expressed on the edge of the invading trophoblast facilitates the trophoblastic invasion by cleaving proMMP-2, a known substrate of MT1-MMP, in the decidua. Immunohistochemical examination of early conceptuses confirmed that the trophoblast cells actively invading the endometrium in vivo express MT1-MMP strongly. It is suggested, furthermore, that the expression of MT1-MMP might be downregulated by cell-cell contact in mouse trophoblast cells, as in the mouse mammary epithelial cell line HC11.


Assuntos
Blastocisto/enzimologia , Colagenases/genética , Expressão Gênica , Placenta/enzimologia , Trofoblastos/enzimologia , Animais , Comunicação Celular , Células Cultivadas , Colagenases/análise , Feminino , Masculino , Metaloproteinase 1 da Matriz , Camundongos , Camundongos Endogâmicos ICR , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , DNA Polimerase Dirigida por RNA
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