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1.
Phys Rev Lett ; 118(24): 242002, 2017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-28665642

RESUMO

We report the first beam-target double-polarization asymmetries in the γ+n(p)→π^{-}+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several γnN^{*} resonance photocouplings.

2.
J Nucl Cardiol ; 24(3): 862-871, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27225517

RESUMO

BACKGROUND: Radioligands of 18-kDa translocator protein (TSPO) expressed on activated macrophages are a potential approach for imaging of inflammation in atherosclerosis. We evaluated a novel TSPO-targeted tracer 18F-FEMPA for the detection of atherosclerotic plaque inflammation in mice. METHODS AND RESULTS: The distribution kinetics of 18F-FEMPA was evaluated by in vivo PET/CT imaging. 18F-FEMPA uptake was compared in atherosclerotic (LDLR-/-ApoB100/100, n = 10) and healthy mice (C57BL/6 N, n = 7) ex vivo at twenty minutes post-injection. Biodistribution was analyzed from harvested tissue samples, and aortas were sectioned for autoradiography. Aortas of LDLR-/-ApoB100/100 mice showed large, macrophage-rich atherosclerotic plaques. In vivo, 18F-FEMPA showed rapid blood clearance but no difference in aortic uptake between atherosclerotic and healthy mice. In the mice studied ex vivo at 20 minutes post-injection, quantification of radioactivity in the whole aorta showed 1.3-fold higher 18F-FEMPA accumulation in atherosclerotic than healthy mice (P = .028). Autoradiography showed higher tracer uptake in plaque areas with high macrophage content as compared with areas of no macrophages (count densities 190 ± 54 vs 40 ± 13 PSL/mm2, P < .001), but the uptake in the plaques was not higher than in the normal vessel wall (230 ± 78 PSL/mm2). In vitro blocking showed specific accumulation in mouse and human atherosclerotic plaques. Immunohistochemistry confirmed co-localization of TSPO and macrophages. CONCLUSIONS: 18F-FEMPA shows rapid blood clearance and uptake in the mouse aorta. Uptake in atherosclerotic plaques correlated with the amount of macrophages, but did not exceed that in the normal vessel wall.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/metabolismo , Hidrocarbonetos Fluorados/farmacocinética , Piridinas/farmacocinética , Receptores de GABA/metabolismo , Animais , Biomarcadores/metabolismo , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Especificidade de Órgãos , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
3.
Am J Physiol Endocrinol Metab ; 305(5): E611-9, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23839525

RESUMO

Accelerated fetal myocardial growth with altered cardiac function is a well-documented complication of human diabetic pregnancy, but its pathophysiology is still largely unknown. Our aim was to explore the mechanisms of fetal cardiac remodeling and cardiovascular hemodynamics in a rat model of maternal pregestational streptozotocin-induced hyperglycemia. The hyperglycemic group comprised 107 fetuses (10 dams) and the control group 219 fetuses (20 dams). Fetal cardiac function was assessed serially by Doppler ultrasonography. Fetal cardiac to thoracic area ratio, newborn heart weight, myocardial cell proliferative and apoptotic activities, and cardiac gene expression patterns were determined. Maternal hyperglycemia was associated with increased cardiac size, proliferative, apoptotic and mitotic activities, upregulation of genes encoding A- and B-type natriuretic peptides, myosin heavy chain types 2 and 3, uncoupling proteins 2 and 3, and the angiogenetic tumor necrosis factor receptor superfamily member 12A. The genes encoding Kv channel-interacting protein 2, a regulator of electrical cardiac phenotype, and the insulin-regulated glucose transporter 4 were downregulated. The heart rate was lower in fetuses of hyperglycemic dams. At 13-14 gestational days, 98% of fetuses of hyperglycemic dams had holosystolic atrioventricular valve regurgitation and decreased outflow mean velocity, indicating diminished cardiac output. Maternal hyperglycemia may lead to accelerated fetal myocardial growth by cardiomyocyte hyperplasia. In fetuses of hyperglycemic dams, expression of key genes that control and regulate cardiomyocyte electrophysiological properties, contractility, and metabolism are altered and may lead to major functional and clinical implications on the fetal heart.


Assuntos
Apoptose/fisiologia , Coração Fetal/patologia , Hiperglicemia/sangue , Hiperglicemia/patologia , Gravidez em Diabéticas/sangue , Animais , Feminino , Coração Fetal/diagnóstico por imagem , Frequência Cardíaca/fisiologia , Hiperplasia , Tamanho do Órgão/fisiologia , Gravidez , Gravidez em Diabéticas/diagnóstico por imagem , Gravidez em Diabéticas/patologia , RNA/química , RNA/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler
4.
Anim Microbiome ; 5(1): 66, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129884

RESUMO

The skin of animals is enveloped by a symbiotic microscopic ecosystem known as the microbiome. The host and microbiome exhibit a mutualistic relationship, collectively forming a single evolutionary unit sometimes referred to as a holobiont. Although the holobiome theory highlights the importance of the microbiome, little is known about how the skin microbiome contributes to protecting the host. Existing studies focus on humans or captive animals, but research in wild animals is in its infancy. Specifically, the protective role of the skin microbiome in hibernating animals remains almost entirely overlooked. This is surprising, considering the massive population declines in hibernating North American bats caused by the fungal pathogen Pseudogymnoascus destructans, which causes white-nose syndrome. Hibernation offers a unique setting in which to study the function of the microbiome because, during torpor, the host's immune system becomes suppressed, making it susceptible to infection. We conducted a systematic review of peer-reviewed literature on the protective role of the skin microbiome in non-human animals. We selected 230 publications that mentioned pathogen inhibition by microbes residing on the skin of the host animal. We found that the majority of studies were conducted in North America and focused on the bacterial microbiome of amphibians infected by the chytrid fungus. Despite mentioning pathogen inhibition by the skin microbiome, only 30.4% of studies experimentally tested the actual antimicrobial activity of symbionts. Additionally, only 7.8% of all publications studied defensive cutaneous symbionts during hibernation. With this review, we want to highlight the knowledge gap surrounding skin microbiome research in hibernating animals. For instance, research looking to mitigate the effects of white-nose syndrome in bats should focus on the antifungal microbiome of Palearctic bats, as they survive exposure to the Pseudogymnoascus destructans -pathogen during hibernation. We also recommend future studies prioritize lesser-known microbial symbionts, such as fungi, and investigate the effects of a combination of anti-pathogen microbes, as both areas of research show promise as probiotic treatments. By incorporating the protective skin microbiome into disease mitigation strategies, conservation efforts can be made more effective.

5.
Arterioscler Thromb Vasc Biol ; 31(5): 1011-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21372297

RESUMO

OBJECTIVE: Atherosclerotic plaques with large lipid cores and inflammation contain regions of hypoxia. We examined the uptake of 2-(2-nitro-1H-imidazol-1-yl)-N-(2,2,3,3,3-pentafluoropropyl) acetamide ([18F]EF5), a specific marker of hypoxia labeled for positron emission tomography, in mouse atherosclerotic plaques. METHODS AND RESULTS: Atherosclerotic mice of 2 different genetic backgrounds (low-density lipoprotein receptor-/- apolipoprotein B100/100 and insulin-like growth factor II/low-density lipoprotein receptor-/- apolipoprotein B100/100) were first fed a Western diet to induce development of plaques with variable phenotypes and then injected with [18F]EF5. C57BL/6N mice served as controls. Aortas were dissected for biodistribution studies, autoradiography, histology, and immunohistochemistry. Uptake of [18F]EF5 was significantly higher in the aortas of mice with large atherosclerotic plaques than in the C57BL/6N controls. Furthermore, autoradiography demonstrated, on average, 2.0-fold higher [18F]EF5 uptake in atherosclerotic plaques than in the adjacent normal vessel wall. Hypoxia in plaques was verified by using an EF5 adduct-specific antibody and pimonidazole. The blood clearance of [18F]EF5 was slow, with blood radioactivity remaining relatively high up to 180 minutes after injection. CONCLUSIONS: Large atherosclerotic plaques in mice contained hypoxic areas and showed uptake of [18F]EF5. Despite its slow blood clearance, the high uptake of [18F]EF5 in plaques suggested that plaque hypoxia is a potential target for identifying high-risk plaques noninvasively.


Assuntos
Aorta/diagnóstico por imagem , Aterosclerose/diagnóstico por imagem , Etanidazol/análogos & derivados , Radioisótopos de Flúor , Hidrocarbonetos Fluorados , Hipóxia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Análise de Variância , Animais , Aorta/metabolismo , Aorta/patologia , Apolipoproteína B-100/deficiência , Apolipoproteína B-100/genética , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Autorradiografia , Modelos Animais de Doenças , Etanidazol/farmacocinética , Feminino , Radioisótopos de Flúor/farmacocinética , Genótipo , Hidrocarbonetos Fluorados/farmacocinética , Hipóxia/genética , Hipóxia/metabolismo , Hipóxia/patologia , Imuno-Histoquímica , Fator de Crescimento Insulin-Like II/deficiência , Fator de Crescimento Insulin-Like II/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nitroimidazóis , Fenótipo , Compostos Radiofarmacêuticos/farmacocinética , Receptores de LDL/deficiência , Receptores de LDL/genética , Distribuição Tecidual
6.
Minerva Gastroenterol Dietol ; 58(4): 347-54, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23207611

RESUMO

Chronic pancreatitis is a disease that involves the lymphocytic inflammation of the pancreatic gland, the destruction and fibrous transformation of the endocrine and ductal structures. An involvement of the immune system in the disease progression is assumed and possibly allows immune modulation as a novel treatment strategy. We used a new model of experimental chronic pancreatitis to examine the effect of immune modulation with the mTOR-inhibitor rapamycin on clinical, chemical and histological parameters of chronic pancreatitis. Pancreatitis was induced by injecting 8 mg/kg bodyweight DBTC intravenously in male Sprague Dawley rats. 24 and 72 hours later, 20 µg/kg bodyweight cerulein was injected intraperitoneally to simulate recurrent attacks of pancreatitis typical for the clinical course. 48 hours after the DBTC injection, rats were randomly allocated to placebo or sirolimus (1.5 mg/kg bw i.p.). The treatment was repeated every 24hours for 5 days. The rats were sacrificed 7, 14, 21 and 35 days after DBTC injection. Histologic examination revealed a reduced acute pancreatic damage in the treatment group in the first week and less chronic changes in the further course. ALT and amylase increased in Placebo animals over the observation period and was lower in sirolimus treated animals. Oral glucose tolerance test showed that all placebo animals were diabetic four weeks after DBTC while sirolimus treated animals were normoglycemic. An early, limited treatment with immunomodulatory and antifibrotic agents like sirolimus can positively influence the detrimental course of experimental chronic pancreatitis and may offer a treatment alternative in humans.


Assuntos
Imunomodulação , Imunossupressores/uso terapêutico , Pancreatite Crônica/tratamento farmacológico , Sirolimo/uso terapêutico , Animais , Modelos Animais de Doenças , Progressão da Doença , Teste de Tolerância a Glucose , Masculino , Pancreatite Crônica/induzido quimicamente , Pancreatite Crônica/patologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
7.
Eur J Nucl Med Mol Imaging ; 36(1): 73-80, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18712383

RESUMO

PURPOSE: The ligand [(11)C]PK11195 binds with high affinity and selectivity to peripheral benzodiazepine receptor, expressed in high amounts in macrophages. In humans, [(11)C]PK11195 has been used successfully for the in vivo imaging of inflammatory processes of brain tissue. The purpose of this study was to explore the feasibility of [(11)C]PK11195 in imaging inflammation in the atherosclerotic plaques. METHODS: The presence of PK11195 binding sites in the atherosclerotic plaques was verified by examining the in vitro binding of [(3)H]PK11195 onto mouse aortic sections. Uptake of intravenously administered [(11)C]PK11195 was studied ex vivo in excised tissue samples and aortic sections of a LDLR/ApoB48 atherosclerotic mice. Accumulation of the tracer was compared between the atherosclerotic plaques and non-atherosclerotic arterial sites by autoradiography and histological analyses. RESULTS: The [(3)H]PK11195 was found to bind to both the atherosclerotic plaques and the healthy wall. The autoradiography analysis revealed that the uptake of [(11)C]PK11195 to inflamed regions in plaques was more prominent (p = 0.011) than to non-inflamed plaque regions, but overall it was not higher than the uptake to the healthy vessel wall. Also, the accumulation of (11)C radioactivity into the aorta of the atherosclerotic mice was not increased compared to the healthy control mice. CONCLUSIONS: Our results indicate that the uptake of [(11)C]PK11195 is higher in inflamed atherosclerotic plaques containing a large number of inflammatory cells than in the non-inflamed plaques. However, the tracer uptake to other structures of the artery wall was also prominent and may limit the use of [(11)C]PK11195 in clinical imaging of atherosclerotic plaques.


Assuntos
Aterosclerose/metabolismo , Aterosclerose/patologia , Inflamação/metabolismo , Inflamação/patologia , Isoquinolinas/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Autorradiografia , Biomarcadores/metabolismo , Radioisótopos de Carbono/química , Estudos de Viabilidade , Isoquinolinas/química , Isoquinolinas/farmacocinética , Masculino , Camundongos , Distribuição Tecidual
8.
Mol Biol Cell ; 17(1): 67-79, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16251361

RESUMO

The ErbB1 and ErbB2 receptors are oncogenes with therapeutic significance in human cancer, whereas the transforming potential of the related ErbB4 receptor has remained controversial. Here, we have addressed whether four alternatively spliced ErbB4 isoforms differ in regulating cellular responses relevant for tumor growth. We show that the two tumor necrosis factor-alpha converting enzyme (TACE)-cleavable ErbB4 isoforms (the juxtamembrane [JM]-a isoforms) were overexpressed in a subset of primary human breast cancers together with TACE. The overexpression of the JM-a cytoplasmic (CYT)-2 ErbB4 isoform promoted ErbB4 phosphorylation, survival of interleukin-3-dependent cells, and proliferation of breast cancer cells even in the absence of ligand stimulation, whereas activation of the other three ErbB4 isoforms required ligand stimulation. Ligand-independent cellular responses to ErbB4 JM-a CYT-2 overexpression were regulated by both tyrosine kinase activity and a two-step proteolytic generation of an intracellular receptor fragment involving first a TACE-like proteinase, followed by gamma-secretase activity. These data suggest a novel transforming mechanism for the ErbB4 receptor in human breast cancer that is 1) specific for a single receptor isoform and 2) depends on proteinase cleavage and kinase activity but not ligand activation of the receptor.


Assuntos
Receptores ErbB/química , Receptores ErbB/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Processamento de Proteína Pós-Traducional , Proteínas ADAM/metabolismo , Proteína ADAM17 , Adulto , Idoso , Idoso de 80 Anos ou mais , Secretases da Proteína Precursora do Amiloide , Ácido Aspártico Endopeptidases , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Proliferação de Células , Sobrevivência Celular , Dimerização , Endopeptidases/metabolismo , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Ligantes , Pessoa de Meia-Idade , Neoplasias/genética , Fosforilação , Fosfotirosina/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptor ErbB-4 , Transdução de Sinais , Solubilidade
9.
Biochim Biophys Acta ; 1761(7): 745-56, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16757211

RESUMO

Secreted phospholipases A(2) (sPLA(2)) form a group of low-molecular weight enzymes that catalyze the hydrolysis of phospholipids. Some sPLA(2)s are likely to play a role in inflammation, cancer, and as antibacterial enzymes in innate immunity. We developed specific and sensitive time-resolved fluroimmunoassays (TR-FIA) for mouse group (G) IB, GIIA, GIID, GIIE, GIIF, GV and GX sPLA(2)s and measured their concentrations in mouse serum and tissues obtained from both Balb/c and C57BL/6J mice. We also analyzed the mRNA expression of the sPLA(2)s by quantitative real-time reverse transcriptase PCR (qPCR). In most tissues, the concentrations of sPLA(2) proteins corresponded to the expression of sPLA(2)s at the mRNA level. With a few exceptions, the sPLA(2) proteins were found in the gastrointestinal tract. The qPCR results showed that GIB sPLA(2) is synthesized widely in the gastrointestinal tract, including esophagus and colon, in addition to stomach and pancreas. Our results also suggest that the loss of GIIA sPLA(2) in the intestine of GIIA sPLA(2)-deficient C57BL/6J mice is not compensated by other sPLA(2)s under normal conditions. Outside the gastrointestinal tract, sPLA(2)s were expressed occasionally in a number of tissues. The TR-FIAs developed in the current study may serve as useful tools to measure the levels of sPLA(2) proteins in mouse serum and tissues in various experimental settings.


Assuntos
Fosfolipases A/biossíntese , Animais , Feminino , Imunoensaio , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Especificidade de Órgãos , Fosfolipases A/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/genética
10.
Biochim Biophys Acta ; 1733(2-3): 210-23, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15863368

RESUMO

Time-resolved fluoroimmunoassays (TR-FIA) were developed for all human secreted phospholipases A(2) (PLA(2)), viz. group (G) IB, GIIA, GIID, GIIE, GIIF, GIII, GV, GX and GXIIA PLA(2) and the GXIIB PLA(2)-like protein. Antibodies were raised in rabbits against recombinant human PLA(2) proteins and used in sandwich-type TR-FIAs as both catching and detecting antibodies, the latter after labeling with Europium. The antibodies were non-cross-reactive. The analytical sensitivities were 1 microg/L for the TR-FIA for GIB PLA(2), 1 microg/L (GIIA), 35 microg/L (GIID), 3 microg/L (GIIE), 4 microg/L (GIIF), 14 microg/L (GIII), 11 microg/L (GV), 2 microg/L (GX), 92 microg/L (GXIIA) and 242 microg/L (GXIIB). All secreted PLA(2)s were assayed by these TR-FIAs in serum samples from 34 patients (23 men and 11 women, mean age 53.2 years) treated in an intensive care unit for septic infections, and in control samples from 28 volunteer blood donors (14 men and 14 women, mean age 57.0 years). Five serum samples (3 in the sepsis group and 2 in the blood donor group) gave high TR-FIA signals that were reduced to background (blank) levels by the addition of non-immune rabbit IgG to the sera. This reactivity was assumed to be due to the presence of heterophilic antibodies in these subjects. In all other subjects, including septic patients and healthy blood donors, the TR-FIA signals for GIID, GIIE, GIIF, GIII, GV, GX and GXIIA PLA(2) and the GXIIB PLA(2)-like protein were at background (blank) levels. Four patients in the sepsis group had pancreatic involvement and elevated concentration of GIB PLA(2) in serum (median 19.0 microg/L, range 13.1-33.7 microg/L, n = 4) as compared to the healthy blood donors (median 1.8 microg/L, range 0.8-3.4 microg/L, n = 28, P < 0.0001). The concentration of GIIA PLA(2) in the sera of septic patients (median 315.7 microg/L, range 15.9-979.6 microg/L, n = 34) was highly elevated as compared to that of the blood donors (median 1.8 microg/L, range 0.8-5.8 microg/L, n = 28, P < 0.0001). Our current results confirmed elevated concentrations of GIB and GIIA PLA(2) in the sera of patients suffering from acute pancreatitis or septic infections, respectively, as compared to healthy subjects. However, in the same serum samples, the concentrations of the other secreted PLA(2)s, viz. GIID, GIIE, GIIF, GIII, GV, GX and GXIIA PLA(2) and the GXIIB PLA(2)-like protein were below the respective analytical sensitivities of the TR-FIAs. It is concluded that generalized bacterial infections do not lead to elevated serum levels of GIIE, GIIF, GIII, GV and GX PLA(2)s above the detection limits of the current TR-FIAs.


Assuntos
Fosfolipases A/sangue , Sepse/sangue , Adulto , Idoso , Especificidade de Anticorpos , Feminino , Fluorimunoensaio , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/sangue , Fosfolipases A/normas , Proteínas Recombinantes/sangue , Reprodutibilidade dos Testes
11.
APMIS ; 114(2): 127-30, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16519749

RESUMO

Group IIA phospholipase A2 (PLA2-IIA) is an enzyme which has important roles in inflammation and infection. Recently, a novel human secretory PLA2 called group XIIA PLA2 (PLA2-XIIA) has been identified. Both PLA2-IIA and PLA2-XIIA are bactericidal against Gram-positive bacteria like many other secretory PLA2s. However, PLA2-XIIA is the only known PLA2 displaying significant bactericidal activity against the Gram-negative bacterium Escherichia coli. We examined the antibacterial properties of recombinant human PLA2-IIA and PLA2-XIIA against Helicobacter pylori, a Gram-negative bacterium, in vitro. PLA2-IIA was not bactericidal against H. pylori, whereas PLA2-XIIA effectively killed H. pylori at a concentration of 50 microg/ml but was not bactericidal at concentrations of 0.5 microg/ml and 5 microg/ml.


Assuntos
Antibacterianos/farmacologia , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/crescimento & desenvolvimento , Fosfolipases A/farmacologia , Gastropatias/tratamento farmacológico , Gastropatias/microbiologia , Contagem de Colônia Microbiana , Fosfolipases A2 do Grupo II , Humanos , Fosfolipases A2 , Proteínas Recombinantes/farmacologia
12.
Eur J Nucl Med Mol Imaging ; 33(12): 1461-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16845513

RESUMO

PURPOSE: [(18)F]FDG has been used as an inflammation marker and shown to accumulate in inflammatory atherosclerotic plaques. The aim of this study was to investigate the uptake and location of [(18)F]FDG in atherosclerotic plaque compartments. METHODS: The biodistribution of intravenously administered [(18)F]FDG was analysed in atherosclerotic LDLR/ApoB48 mice (n=11) and control mice (n=9). Digital autoradiography was used to detect the ex vivo distribution in frozen aortic sections. In vitro binding of [(18)F]FDG in human atherosclerotic arteries was also examined. RESULTS: The uptake of [(18)F]FDG was significantly higher in the aorta of atherosclerotic mice as compared with the control mice. Autoradiography of excised arteries showed higher [(18)F]FDG uptake in the plaques than in the healthy vessel wall (mean ratio +/-SD 2.7+/-1.1). The uptake of [(18)F]FDG in the necrotic, calcified sites of the advanced atherosclerotic lesions was 6.2+/-3.2 times higher than that in the healthy vessel wall. The in vitro studies of human arterial sections showed marked binding of [(18)F]FDG to the calcifications but not to other structures of the artery wall. CONCLUSION: In agreement with previous studies, we observed [(18)F]FDG uptake in atherosclerotic plaques. However, prominent non-specific binding to calcified structures was found. This finding warrants further studies to clarify the significance of this non-specific binding in human plaques in vivo.


Assuntos
Artérias/metabolismo , Artérias/patologia , Aterosclerose/metabolismo , Calcinose/metabolismo , Estenose das Carótidas/metabolismo , Fluordesoxiglucose F18/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Apolipoproteína B-48/deficiência , Aterosclerose/complicações , Aterosclerose/patologia , Autorradiografia , Calcinose/complicações , Estenose das Carótidas/complicações , Estenose das Carótidas/patologia , Artéria Femoral/metabolismo , Artéria Femoral/patologia , Fluordesoxiglucose F18/farmacocinética , Humanos , Inflamação/complicações , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Camundongos Knockout , Receptores de LDL/deficiência , Distribuição Tecidual
13.
Cancer Res ; 57(16): 3360-4, 1997 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9269996

RESUMO

Human bladder carcinomas often express high levels of the epidermal growth factor (EGF) receptor. In three human bladder carcinoma cell lines (OBR, T24, and 647V), we show that two EGF receptor ligands, namely EGF and transforming growth factor alpha, enhanced the apoptosis due to serum starvation on cells cultured as monolayers. Conversely, EGF and transforming growth factor alpha prevented apoptosis when the same serum-starved cells were cultured as three-dimensional spheroids. Both stimulation and inhibition of apoptosis by EGF were associated with p21 WAF1/CIP1 overexpression. In 647V spheroids, EGF protection against radiation-induced apoptosis was negated by genistein and tyrphostin AG1478, suggesting that blockade of the EGF signal transduction in patients with bladder cancer may improve the radiotherapy efficacy.


Assuntos
Apoptose/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Proteínas de Neoplasias/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Fator de Crescimento Transformador alfa/farmacologia , Tirfostinas , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Apoptose/efeitos da radiação , Meios de Cultura Livres de Soro , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Genisteína , Humanos , Isoflavonas/farmacologia , Nitrilas/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinazolinas/farmacologia , Fatores de Tempo , Células Tumorais Cultivadas , Regulação para Cima
14.
FASEB J ; 17(12): 1609-21, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12958167

RESUMO

Recruitment of vascular smooth muscle cells (SMC) by endothelial cells (EC) is essential for angiogenesis. Endothelial-derived heparin binding EGF-like growth factor (HB-EGF) was shown to mediate this process by signaling via ErbB1 and ErbB2 receptors in SMCs. 1) Analysis of ErbB-ligands demonstrated that primary ECs expressed only HB-EGF and neuregulin-1. 2) Primary SMCs expressed ErbB1 and ErbB2, but not ErbB3 or ErbB4. 3) Consistent with their known receptor specificities, recombinant HB-EGF, but not neuregulin-1, stimulated tyrosine phosphorylation of ErbB1 and ErbB2 and migration in SMCs. 4) Neutralization of HB-EGF or inhibition of ErbB1 or ErbB2 blocked 70-90% of the potential of ECs to stimulate SMC migration. Moreover, 5) angiopoietin-1, an EC effector with a role in recruitment of SMC-like cells to vascular structures in vivo, enhanced EC-stimulated SMC migration by a mechanism involving up-regulation of endothelial HB-EGF. Finally, 6) immunohistochemical analysis of developing human tissues demonstrated that HB-EGF was expressed in vivo in ECs associated with SMCs or pericytes but not in ECs of the hyaloid vessels not associated with SMCs. These results suggest an important role for HB-EGF and ErbB receptors in the recruitment of SMCs by ECs and elaborate on the mechanism by which angiopoietins exert their vascular effects.


Assuntos
Indutores da Angiogênese/farmacologia , Movimento Celular , Endotélio Vascular/fisiologia , Fator de Crescimento Epidérmico/fisiologia , Glicoproteínas de Membrana/farmacologia , Músculo Liso Vascular/fisiologia , Angiopoietina-1 , Células Cultivadas , Endotélio Vascular/metabolismo , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Receptores ErbB/fisiologia , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Músculo Liso Vascular/efeitos dos fármacos , Comunicação Parácrina , Fosforilação , RNA Mensageiro/biossíntese , Receptor ErbB-2/metabolismo , Receptor ErbB-2/fisiologia
15.
J Histochem Cytochem ; 48(11): 1469-78, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11036090

RESUMO

Group II phospholipase A2 (PLA2) is an acute-phase protein and an important component of the host defense against bacteria. In this study we investigated the distribution of PLA2 protein by immunohistochemistry and the distribution of mRNA of PLA2 by Northern blotting and in situ hybridization in rat tissues. PLA2 protein was localized in the Paneth cells of the intestinal mucosa, chondrocytes and the matrix of cartilage, and megakaryocytes in the spleen. By Northern blotting, mRNA of PLA2 was found in the gastrointestinal tract, lung, heart, and spleen. By in situ hybridization, PLA2 mRNA was localized in the Paneth cells of the small intestinal mucosa but in no other cell types. Our results show specific distribution of PLA2 in a limited number of cell types in rat tissues. The reagents developed in this study (the anti-rat PLA2 antibody and probes for Northern blotting and in situ hybridization of mRNA of rat PLA2) will provide useful tools for future studies concerning the role of PLA2 in various experimental disease models.


Assuntos
Fosfolipases A/metabolismo , RNA Mensageiro/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos , Sequência de Bases , Northern Blotting , Reações Cruzadas , Fosfolipases A2 do Grupo II , Imuno-Histoquímica , Hibridização In Situ , Dados de Sequência Molecular , Especificidade de Órgãos , Celulas de Paneth/enzimologia , Fosfolipases A/imunologia , Fosfolipases A2 , Ratos , Proteínas Recombinantes/metabolismo
16.
J Histochem Cytochem ; 45(8): 1109-19, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9267471

RESUMO

Group II phospholipase A2 (PLA2) has been proposed to play an important role in inflammation and defense against bacterial infection. We investigated tissues of transgenic mice expressing the human group II PLA2 gene by immunohistochemistry using rabbit anti-human group II PLA2 antibodies, and by in situ hybridization by probing with human group II PLA2 mRNA anti-sense (test) and sense (control) riboprobes. By immunohistochemistry, human group II PLA2 was found in various mouse tissues and cell types including hepatocytes, proximal tubule cells of the kidney, epithelial cells of the renal pelvis, urinary bladder and ureter, granulosa cells of Graafian follicles, aortic intima and media, cartilage, epiphyseal bone, bronchial epithelial cells, and connective tissue cells in the dermis. By in situ hybridization, group II PLA2 mRNA was localized in hepatocytes, epidermal cells, dermal cells, connective tissue fibroblasts, epithelial and smooth muscle cells of the urinary bladder, and cells of Bowman's capsule. These results show that human group II PLA2 is expressed in large amounts in hepatocytes and many extrahepatic tissues of the transgenic mice. These animals provide a useful new tool for studies on the metabolism, in vivo effects, and physiological and pathological roles of phospholipase A2.


Assuntos
Fosfolipases A/metabolismo , Animais , Aorta/metabolismo , Feminino , Genitália Feminina/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Sistema Musculoesquelético/metabolismo , Fosfolipases A2 , RNA Mensageiro/análise , Pele/metabolismo , Distribuição Tecidual , Sistema Urinário/metabolismo
17.
APMIS ; 100(4): 335-40, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1316130

RESUMO

Immunohistochemical characteristics of a mucinous islet-cell carcinoma of the pancreas are described. The tumour presented with jaundice in a 59-year-old male. It consisted of polygonal atypical cells forming a reticular pattern, and invaded the common bile duct. In DNA flow cytometry, the tumour cells showed a clear-cut aneuploid peak. Intercellular mucin was abundant. A panel of antisera and monoclonal markers was applied in the immunohistochemical analysis. In addition to general epithelial and endocrine markers, the tumour cells showed a focal positive immunoreaction with anti-glucagon, anti-insulin, anti-vasoactive intestinal polypeptide, anti-pancreatic secretory trypsin inhibitor and anti-phospholipase A2 antigen. At the ultrastructural level, mucous and neuroendocrine granules were demonstrated in the same tumour cells.


Assuntos
Adenoma de Células das Ilhotas Pancreáticas/patologia , Carcinoma/patologia , Adenoma de Células das Ilhotas Pancreáticas/imunologia , Adenoma de Células das Ilhotas Pancreáticas/metabolismo , Carcinoma/imunologia , Carcinoma/metabolismo , Grânulos Citoplasmáticos/ultraestrutura , DNA de Neoplasias/análise , Glucagon/metabolismo , Humanos , Técnicas Imunoenzimáticas , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Mucina-1 , Mucinas/metabolismo , Proteínas S100/metabolismo , Inibidores da Tripsina/metabolismo
18.
Pancreas ; 19(1): 62-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10416694

RESUMO

To examine the role of lymphocyte activation in the development of local and systemic complications in acute pancreatitis, we compared disease severity of choline-deficient, 0.5% ethionine supplemented (CDE) diet-induced acute pancreatitis in T- and B-cell deficient SCID mice and immunocompetent C.B-17 mice. Twenty-five female SCID and 17 female C.B-17 mice were fasted for 24 h and fed a CDE diet for 72 h. Twenty SCID and 12 C.B-17 mice were bled and their organs removed for histologic evaluation. Five control animals of both kinds were fed a regular diet for 6 days. Lung, kidney, and pancreas were examined microscopically, and pancreatic damage scored. Apoptosis was detected by DNA nick-end labeling and confirmed by DNA laddering. Trypsinogen-activation peptide was measured by enzyme-linked immunosorbent assay (ELISA), and the catalytic activity of PLA2 was determined by a radiometric assay. Four-day mortality was 10% in SCID and 33% in C.B-17 mice, and 10-day mortality was 0 in SCID and 60% in C.B-17 mice. SCID mice had mild pulmonary damage, whereas pulmonary injury was severe in C.B-17 mice. Pancreatic damage was severe in both groups. Even though in situ staining of apoptotic cells was found in all pancreatitis animals, apoptosis was confirmed by DNA laddering only in C.B-17 mice. In SCID mice, apoptotic cell staining positively correlated with necrosis (r = 0.91; p < 0.001). Plasma TAP and PLA2 catalytic activity did not differ significantly between the groups. In conclusion, the absence of T and B lymphocytes prevents severe pulmonary injury resulting from acute pancreatitis but does not influence pancreatic or renal damage. Our results suggest that systemic lymphocyte activation does not affect the initiating events that trigger pancreatic injury but modulates the systemic response, in particular, pulmonary injury caused by acute pancreatitis.


Assuntos
Ativação Linfocitária , Pancreatite/fisiopatologia , Imunodeficiência Combinada Severa/fisiopatologia , Doença Aguda , Animais , Apoptose , Deficiência de Colina/complicações , Dieta , Ensaio de Imunoadsorção Enzimática , Feminino , Marcação In Situ das Extremidades Cortadas , Pulmão/patologia , Camundongos , Camundongos SCID , Oligopeptídeos/sangue , Pancreatite/etiologia , Pancreatite/metabolismo , Pancreatite/patologia , Fosfolipases A/metabolismo , Fosfolipases A2 , Imunodeficiência Combinada Severa/metabolismo
19.
Exp Toxicol Pathol ; 48(1): 77-9, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8919273

RESUMO

The effects of chronic alcohol intake and carbachol stimulation on pancreatic muscarinic receptor binding and insulin concentrations were studied in the rat pancreas. There was a strong correlation between the number of muscarinic receptors and the concentration of insulin in the pancreas. The concentration of insulin decreased in the pancreas after long-term ethanol exposure and increased after carbachol stimulation. These results indicate that the secretion of insulin is mediated via the muscarinic receptor pathway, and that the changes in the number of muscarinic receptors may have a role in insulin deficiency after long-term alcohol consumption.


Assuntos
Carbacol/farmacologia , Etanol/metabolismo , Etanol/toxicidade , Insulina/metabolismo , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Receptores Muscarínicos/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Etanol/administração & dosagem , Masculino , N-Metilescopolamina , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Receptores Muscarínicos/química , Derivados da Escopolamina/análise
20.
Therapie ; 45(6): 509-12, 1990.
Artigo em Francês | MEDLINE | ID: mdl-2080490

RESUMO

We describe five cases of vasculitis noted a few days after influenza vaccination. This complication has occurred in four women, and the mean age was 76 years. Although cutaneous biopsy has confirmed leucocytoclasic vasculitis in only one case, the clinical characteristics were evocative in the other cases. No systemic complication were noted. Spontaneous retrocession was noted in four patients and following corticosteroids once. To our knowledge only few cases of vasculitis has been previously reported after influenza vaccination. The mechanisms are unknown but preservatives may have some responsibilities.


Assuntos
Influenza Humana/prevenção & controle , Vacinação/efeitos adversos , Vasculite/induzido quimicamente , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
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