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1.
Neoplasma ; 61(6): 724-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25150317

RESUMO

Ovarian cancer is the type of cancer with the highest mortality rate among gynaecologic malignancies. Due to lack of screening tools, this disease is mainly diagnosed at a progressed stage, when it is too late to adequate therapy. Despite many attempts, enough sensitive and specific biomarker was not still uncovered. Fluorescence spectroscopy has proven to be a useful diagnostic tool with high efficiency. Fluorescence detection has three major advantages over other light-based investigation methods: high sensitivity, high speed, and reliability. Biological materials consist of a number of intrinsic fluorescent compounds -autofluorophores, which are associated with cardinal metabolic pathways. It is well known, that cancerous tissue metabolism is altered compared to healthy one, what influence also intrinsic fluorophores composition of bodily fluids. Urine is one of the biological fluids that could be obtained most easily and displays a blue - green fluorescence that can change in case of pathological process. Analysis of urine autofluorescence is non invasive and simple technique. Using fluorescent spectroscopy, ovarian cancer patients and healthy control group were discerned with high significance, so we predict that fluorescence analysis of urine could be a potential means of ovarian cancer screening.


Assuntos
Neoplasias Ovarianas/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluorescência , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Espectrometria de Fluorescência
2.
Scand J Med Sci Sports ; 22(6): 756-63, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21535187

RESUMO

The autonomic nervous activity was assessed following supramaximal exercise through heart rate (HR) and blood pressure (BP) variability (HRV and BPV) and baroreflex sensitivity (BRS). The beat-to-beat HR and BP were recorded during the supine and standing states before (PRE) and at 60 (R60) and 120 min (R120) following single (one Wingate, 1W) and multiple sprint intervals (four Wingates interspersed with 4 min of light cycling, 4W). The supine low frequency (LF) component was increased (P<0.001) and the high frequency (HF) was reduced (P<0.01) at R60 (LF, 178.1 ± 11.0; HF, 74.8 ± 10.5) compared with PRE (LF, 140.2 ± 7.4; HF, 110.4 ± 7.2) after both exercises. Supine systolic BPV LF:HF was higher at R60 (4.6 ± 1.4) compared with PRE (6.8 ± 2.4) only after 4W (P=0.035). Supine BRS was lower (P<0.001) at R60 (6.8 ± 1.1) than at PRE (15.3 ± 1.8) and R120 (11.3 ± 1.3). BRS at R120 remained lower after 4W (P=0.02). Standing BRS was less (P<0.001) at R60 (2.3 ± 0.5) than at PRE (5.6 ± 0.8) or R120 (3.7 ± 0.6) and returned to PRE values only after 1W. We concluded that (a) autonomic balance is shifted to a greater sympathetic and less parasympathetic activation following both types of exercise, (b) it takes longer than 1 h to recover following supramaximal exercise and (c) the recovery is longer after 4W than 1W.


Assuntos
Barorreflexo , Pressão Sanguínea , Frequência Cardíaca , Sistema Nervoso Parassimpático/fisiologia , Corrida/fisiologia , Sistema Nervoso Simpático/fisiologia , Adulto , Análise de Variância , Humanos , Ácido Láctico/sangue , Masculino , Decúbito Dorsal , Fatores de Tempo , Adulto Jovem
3.
Eur J Appl Physiol ; 112(7): 2777-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22101870

RESUMO

The effects of physical exercise stress on the endocannabinoid system in humans are almost unexplored. In this prospective study, we investigated in a crossover design and under field conditions at different altitudes the effects of physical exercise on the endocannabinoid system (ECS) in 12 trained healthy volunteers. For determination of alterations on the ECS three different protocols were analyzed: Protocol A (physical exercise at lower altitude) involved strenuous hiking below 2,100 m, whereas Protocol B (physical exercise by active ascent to high altitude) involved hiking up to 3,196 m, an accommodation at the cottage and a descent the next day. Protocol C (passive ascent) included a helicopter ascent to 3,196 m, an overnight stay at this altitude and a flight back to the base camp the following day. The cumulative hiked altitude in Protocol A and B was comparable (~1,650 m). The blood EC concentrations of anandamide increased significantly in Protocol A/B from baseline (T0) 0.12 ± 0.01/0.16 ± 0.02 (mean ± SEM) to 0.27 ± 0.02/0.42 ± 0.02 after exercise (T1) (p < 0.05). Anandamide levels in Protocol C remained stable at 0.20 ± 0.02. We conclude that the ECS is activated upon strenuous exercise whereas the combination with hypoxic stress further increases its activity. The reduced partial pressure of oxygen at high altitude alone did not affect this system. In summary, physical exercise activates the endocannabinoid system, whereas the combination with high altitude enhances this activation. This discloses new perspectives to adaptation mechanisms to physical exercise.


Assuntos
Altitude , Ácidos Araquidônicos/sangue , Moduladores de Receptores de Canabinoides/sangue , Endocanabinoides , Exercício Físico/fisiologia , Resistência Física/fisiologia , Esforço Físico/fisiologia , Alcamidas Poli-Insaturadas/sangue , Adaptação Fisiológica/fisiologia , Humanos , Masculino , Adulto Jovem
4.
Physiol Res ; 68(Suppl 4): S483-S490, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-32118480

RESUMO

Endometrial cancer is one of the most frequent gynecological malignancies present in more than 95 % of all uterine cancers. In spite of that, screening of such disease is not commonly performed in clinical practice due to enormous costs and relatively low sensitivity. Therefore, developing an effective screening test to diagnose endometrial cancer at early stages is of great importance for the clinical area of investigation. In this work, we applied urinary proteomics (i.e., bottom-up proteomic approach followed by nano HPLC-ESI-MS/MS) in patients with endometrial cancer, with respect to find proteins aimed for the early diagnostics and screening. According to the results, the significant semi-quantitative changes were observed in urinary proteome of treated patients. The proteins that may be pivotal in pathogenesis of endometrial cancer, like cadherin-1 (CDH1), vitronectin (VTN) and basement membrane specific-heparan sulphate proteoglycan core protein (HSPG2) were down-regulated, when compared to the control group. Ultimately, it can be stated that urinary proteomics has a potential for the searching of cancer protein biomarkers based on their altered concentration.


Assuntos
Biomarcadores/urina , Carcinoma Endometrioide/urina , Neoplasias do Endométrio/urina , Proteoma , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade
5.
RSC Adv ; 8(54): 30932-30936, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35548741

RESUMO

Electrohydrodynamic lithography (EHDL) is a parallel patterning process which typically makes use of topographically structured electrodes to guide pattern formation along areas of higher electrical field strength. The main driving force for pattern formation is an electrostatic pressure acting on a thin film polymer surface caused by a voltage applied between a top and bottom electrode. We here demonstrate that the principle can be applied using an addressable electrode composed of interdigitated fingers. Depending on the applied voltages, line patterns with different periodicities were fabricated. Our proof-of-concept experiments pave the way for a parallel pattern replication process where a serially addressed master is used. We complement the experiments by modelling the potentials across the electrodes and electrostatic forces acting on the polymer surface using different addressing schemes. Numerical simulations of the experimental setup pointed to some critical issues we experienced during the design of the experiments.

6.
Neuroscience ; 149(3): 561-72, 2007 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-17920205

RESUMO

The mesotelencephalic dopamine system shows substantial genetic variation which fundamentally affects normal and pathological behaviors related to motor function, motivation, and learning. Our earlier radioenzyme assay studies demonstrated significantly higher activity of tyrosine hydroxylase (TH), the first and rate limiting enzyme in the biosynthesis of catecholamine neurotransmitters, in the substantia nigra-ventral tegmental area of BALB/cJ mice in comparison with that of C57BL/6ByJ mice. Here, using quantitative immunoblotting and immunocytochemistry, we tested the hypothesis that mesencephalic TH protein content and number of nigral TH-positive neurons show strain-dependent differences in C57BL/6ByJ and BALB/cJ parallel to those observed in the TH activity studies. Immunoblotting experiments detected significantly higher mesencephalic TH protein content in BALB/cJ in comparison to C57BL/6ByJ (P<0.05). Immunocytochemical studies demonstrated that the number of TH-positive cells in substantia nigra was 31.3% higher in BALB/cJ than that in C57BL/6ByJ (P<0.01), while the average dopamine neuron volume was not significantly different. In a search for candidate genes that modulate TH content and the size of mesencephalic dopamine neuron populations we also studied near-isogenic mouse sublines derived from the C57BL/6ByJ and BALB/cJ progenitor strains. A whole-genome scan with 768 single nucleotide polymorphism markers indicated that two sublines, C4A6/N and C4A6/B, were genetically very similar (98.3%). We found significantly higher mesencephalic TH protein content in C4A6/B in comparison to C4A6/N (P=0.01), and a tendency for higher number of dopamine neurons in the substantia nigra in C4A6/B in comparison to C4A6/N, which, however, did not reach statistical significance. To identify the genetic source of the TH content difference we analyzed the single nucleotide polymorphism (SNP) genotype data of the whole-genome scan, and detected two small differential chromosome segments on chr. 13 and chr. 14. Microarray gene expression studies and bioinformatic analysis of the two differential regions implicated two cis-regulated genes (Spock1 and Cxcl14, chr. 13), and two growth factor genes [bone morphogenetic protein 6 (Bmp6) (chr. 13), and fibroblast growth factor 14 (Fgf14) (chr. 14)]. Taken together, the results suggest that (1) nigral dopamine neuron number and TH protein content may be genetically associated but further studies are needed to establish unequivocally this linkage, and (2) Spock1, Cxcl14, Bmp6, and Fgf14 are novel candidates for modulating the expression and maintenance of TH content in mesencephalic dopamine neurons in vivo.


Assuntos
Dopamina/fisiologia , Mesencéfalo/fisiologia , Neurônios/fisiologia , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Western Blotting , Contagem de Células , Tamanho Celular , Mapeamento Cromossômico , Biologia Computacional , Imuno-Histoquímica , Mesencéfalo/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Padrões de Referência , Especificidade da Espécie , Substância Negra/citologia , Substância Negra/fisiologia
7.
Oncogene ; 36(46): 6446-6461, 2017 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-28759043

RESUMO

The majority of long noncoding RNAs (lncRNAs) is still poorly characterized with respect to function, interactions with protein-coding genes, and mechanisms that regulate their expression. As for protein-coding RNAs, epigenetic deregulation of lncRNA expression by alterations in DNA methylation might contribute to carcinogenesis. To provide genome-wide information on lncRNAs aberrantly methylated in breast cancer we profiled tumors of the C3(1) SV40TAg mouse model by MCIp-seq (Methylated CpG Immunoprecipitation followed by sequencing). This approach detected 69 lncRNAs differentially methylated between tumor tissue and normal mammary glands, with 26 located in antisense orientation of a protein-coding gene. One of the hypomethylated lncRNAs, 1810019D21Rik (now called Esrp2-antisense (as)) was identified in proximity to the epithelial splicing regulatory protein 2 (Esrp2) that is significantly elevated in C3(1) tumors. ESRPs were shown previously to have a dual role in carcinogenesis. Both gain and loss have been associated with poor prognosis in human cancers, but the mechanisms regulating expression are not known. In-depth analyses indicate that coordinate overexpression of Esrp2 and Esrp2-as inversely correlates with DNA methylation. Luciferase reporter gene assays support co-expression of Esrp2 and the major short Esrp2-as variant from a bidirectional promoter, and transcriptional regulation by methylation of a proximal enhancer. Ultimately, this enhancer-based regulatory mechanism provides a novel explanation for tissue-specific expression differences and upregulation of Esrp2 during carcinogenesis. Knockdown of Esrp2-as reduced Esrp2 protein levels without affecting mRNA expression and resulted in an altered transcriptional profile associated with extracellular matrix (ECM), cell motility and reduced proliferation, whereas overexpression enhanced proliferation. Our findings not only hold true for the murine tumor model, but led to the identification of an unannotated human homolog of Esrp2-as which is significantly upregulated in human breast cancer and associated with poor prognosis.


Assuntos
Metilação de DNA , Estudo de Associação Genômica Ampla/métodos , Neoplasias Mamárias Experimentais/genética , RNA Longo não Codificante/genética , Células 3T3-L1 , Animais , Antígenos Virais de Tumores/genética , Western Blotting , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Mamárias Experimentais/diagnóstico , Camundongos , Camundongos Transgênicos , Prognóstico , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Análise de Sobrevida
8.
J Virol Methods ; 134(1-2): 164-70, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16427706

RESUMO

Single chain variable fragment (scFv) molecules were selected from a synthetic phage display library then cloned into a generic vector for expression of the scFv fused to the light chain constant domain of human immunoglobulin with a C-terminal cysteine residue (scFvC(L)cys). A heterobifunctional maleimide linker was synthesised and a strategy for functionalization of gold with the scFvC(L)cys fusion proteins elaborated. Successful covalent attachment of functional scFvC(L)cys was demonstrated using a surface plasmon resonance-based sensor. The results showed that the immobilised scFvC(L)cys molecules were functional and specific binding curves (with response relative to the concentration of virus antigen) were obtained over more than 25 cycles of binding and dissociation. ScFv molecules lacking the C-terminal cysteine performed poorly in similar experiments. The work demonstrates the feasibility of using simple scFv selection and cloning procedures combined with oriented immobilisation of scFvC(L)cys fusion proteins for robust antigen sensing surfaces in immunosensor or other biotechnological applications.


Assuntos
Anticorpos Antivirais/metabolismo , Técnicas Biossensoriais/métodos , Comovirus/imunologia , Fragmentos de Imunoglobulinas/metabolismo , Região Variável de Imunoglobulina/metabolismo , Sequência de Aminoácidos , Anticorpos Antivirais/genética , Comovirus/química , Comovirus/isolamento & purificação , Regiões Determinantes de Complementaridade/genética , Cisteína , Vetores Genéticos , Ouro/metabolismo , Humanos , Fragmentos de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Maleimidas/síntese química , Maleimidas/metabolismo , Dados de Sequência Molecular , Biblioteca de Peptídeos , Plasmídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Ressonância de Plasmônio de Superfície
9.
FEBS Lett ; 489(2-3): 215-9, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11165252

RESUMO

Potato virus X (PVX)-based vector constructs were generated to investigate the use of an internal ribosome entry site (IRES) sequence to direct translation of a viral gene. The 148-nucleotide IREScp sequence from a crucifer-infecting strain of tobacco mosaic virus was used to direct expression of the PVX coat protein (CP). The IRES was inserted downstream of the gene encoding green fluorescent protein (GFP) and upstream of the PVX CP, in either sense or antisense orientation, such that CP expression depended on ribosome recruitment to the IRES. Stem-loop structures were inserted at either the 3'- or 5'-end of the IRES sequence to investigate its mode of action. In vitro RNA transcripts were inoculated to Nicotiana benthamiana plants and protoplasts: levels of GFP and CP expression were analysed by enzyme-linked immunosorbent assay and the rate of virus cell-to-cell movement was determined by confocal laser scanning microscope imaging of GFP expression. PVX CP was expressed, allowing cell-to-cell movement of virus, from constructs containing the IRES sequence in either orientation, and from the construct containing a stem-loop structure at the 5'-end of the IRES sequence. No CP was expressed from a construct containing a stem-loop at the 3'-end of the IRES sequence. Our results suggest that the IRES sequence is acting in vivo to direct expression of the 3'-proximal open reading frame in a bicistronic mRNA thereby demonstrating the potential of employing IRES sequences for the expression of foreign proteins from plant virus-based vectors.


Assuntos
Vetores Genéticos/genética , Vírus de Plantas/genética , Transfecção/métodos , Sítios de Ligação/genética , Capsídeo/genética , DNA Recombinante , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Plantas Tóxicas , Potexvirus/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Ribossomos/metabolismo , Nicotiana/genética , Vírus do Mosaico do Tabaco/genética
10.
FEBS Lett ; 404(2-3): 307-13, 1997 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-9119085

RESUMO

A significant increase in the expression and activity of tissue transglutaminase (tTG), one of the effector elements of apoptosis, was observed during involution of thymus elicited by treatment with either anti-CD3 antibody or dexamethasone or by irradiation. The blood plasma concentration of epsilon(gamma-glutamyl)lysine isodipeptide, the end-product of the digestion of transglutaminase cross-linked proteins, was also elevated in each of these cases. tTG was localized in cells of the cortical layer of the thymus and immunofluorescence double staining revealed that the enzyme appeared in the apoptotic cells. None of these observations could be made when apoptosis was induced by fas-receptor stimulation. The lack of tTG activity in fas-stimulated cells was accompanied with a less organized apoptotic morphology. Our data suggest that distinct signalling pathways, which induce apoptosis within the same cell type, can differentially regulate the expression of tTG, and this enzyme may be involved in structural stabilization of the apoptotic cells.


Assuntos
Apoptose , Regulação Enzimológica da Expressão Gênica , Transdução de Sinais , Timo/enzimologia , Transglutaminases/biossíntese , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Antígenos CD/fisiologia , Biomarcadores , Dexametasona/análogos & derivados , Dexametasona/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Cinética , Masculino , Camundongos , Camundongos Endogâmicos , Timo/citologia , Timo/fisiologia , Fatores de Tempo , Transglutaminases/análise , Receptor fas/imunologia , Receptor fas/fisiologia
11.
Clin Exp Metastasis ; 18(6): 481-92, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11592305

RESUMO

UNLABELLED: The process of extravasation of the high metastatic Lewis lung carcinoma line was examined in different organs. Four of the five organs (liver, lungs, brain and adrenals) represent the most frequent metastatic sites in humans. In the case of each organ 150-350 tumor cells were analysed. The interaction of tumor cells with endothelial cells and the basement membrane showed significant differences between the organs. In the liver and lungs, endothelial cells were found to migrate onto the surface of the tumor cells, resulting in the removal of tumor cells from the circulation. The process was initiated by development of cytoplasmic projections on the luminal surface of the endothelial cells. In the liver only half of the tumor cells showed basement membrane degradation even after 24 h, although 6 h after injection 40% of the tumor cells were sequestered from the circulation. In the adrenals and brain, tumor cells were not covered by endothelial cells instead, limited retraction of endothelial cells was followed by penetration of the basement membrane. In the kidney both types of tumor cell-endothelial cell interactions were observed, but the process of extravasation was not completed, stopping as the tumor cells reached the basement membrane or the mesangial matrix. The time course of tumor cell extravasation also showed significant differences between the organs. The process was most rapid in case of the liver and adrenals. By 6 h 40-50% of the tumor cells were in the process of extravasation or were in an extracapillary position. These organs are preferential metastatic sites of this tumor line. The time of extravasation was much longer in the other organs (lungs 16 h, brain 48 h), for which this tumor line shows no preference. CONCLUSIONS: (1) Type and duration of tumor cell extravasation differ between the organs. (2) The time needed to reach extraluminal position, but not the type of extravasation correlates with the organ preference. (3) Endothelial cells of the lungs and liver can play a much more active role in the process of extravasation than previously suggested. (4) Tumor cells can complete the metastatic process without reaching a complete extracapillary position; contact with the basement membrane or extracellular matrix seems to be sufficient.


Assuntos
Carcinoma Pulmonar de Lewis/patologia , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Especificidade de Órgãos , Neoplasias das Glândulas Suprarrenais/irrigação sanguínea , Neoplasias das Glândulas Suprarrenais/secundário , Neoplasias das Glândulas Suprarrenais/ultraestrutura , Animais , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/ultraestrutura , Carcinoma Pulmonar de Lewis/irrigação sanguínea , Carcinoma Pulmonar de Lewis/ultraestrutura , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/secundário , Neoplasias Renais/ultraestrutura , Neoplasias Hepáticas Experimentais/irrigação sanguínea , Neoplasias Hepáticas Experimentais/secundário , Neoplasias Hepáticas Experimentais/ultraestrutura , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL
12.
Ann N Y Acad Sci ; 946: 95-107, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11762998

RESUMO

Patients infected with the human immunodeficiency virus exhibit a progressive decline in the CD4 T-cell number, resulting in immunodeficiency and increased susceptibility to opportunistic infections and malignancies. Although CD4 T cell production is impaired in patients infected with HIV, there is now increasing evidence that the primary basis of T cell depletion is accelerated apoptosis of CD4 and CD8 T cells. The rate of lymphocyte apoptosis in HIV infection correlates inversely with the progression of the disease: it is low in long-term progressors and in patients undergoing highly active antiretroviral therapy. Interestingly, only a minor fraction of apoptotic lymphocytes are infected by HIV, indicating that the enhanced apoptosis does not necessarily always serve to remove the HIV+ cells and results from mechanisms other than direct infection. Thus, understanding and influencing the mechanisms of HIV-associated lymphocyte apoptosis may lead to new therapies for HIV disease. In this paper the potential effects of retinoids on CD4 T cell apoptosis is discussed.


Assuntos
Apoptose , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Infecções por HIV/etiologia , Retinoides/imunologia , Retinoides/fisiologia , HIV/genética , Humanos , Ativação Linfocitária , Proteínas Virais
13.
Regul Pept ; 98(1-2): 49-54, 2001 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-11179778

RESUMO

The effects of dopamine (DA) or DA-active drugs on the synthesis of neurohypophyseal (NH) hormones were studied in 13-14 day cultures of isolated NH tissue from rats. The following DA-active compounds were used (10(-6) M in each medium): DA, apomorphine (APM), Pro-Lys-Gly (PLG), butaclamol (B), haloperidol (HP), chlorpromazine (CPZ) and sulpiride (SP). The oxytocin (OT) and vasopressin (VP) contents of the condensed media were determined by RIA after a 1 or 2 h incubation. Significantly increased contents of OT and VP were detected in the tissue culture media following DA, APM or PLG administration. This elevation of NH hormone production could be blocked by previous administration of B or the DA receptor antagonists HP, CPZ or SP. The application of B after DA agonists proved ineffective. The results indicate that NH hormone production can be directly influenced by the DA-ergic system. The DA-ergic control of NH hormone secretion in rats can occur independently of the hypothalamus, at the level of the posterior pituitary.


Assuntos
Antagonistas de Dopamina/farmacologia , Dopamina/farmacologia , Ocitocina/metabolismo , Hipófise/metabolismo , Vasopressinas/metabolismo , Animais , Apomorfina/farmacologia , Butaclamol/farmacologia , Clorpromazina/farmacologia , Técnicas de Cultura , Agonistas de Dopamina/farmacologia , Sinergismo Farmacológico , Haloperidol/farmacologia , Masculino , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Ocitocina/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Ratos , Ratos Wistar , Sulpirida/farmacologia , Vasopressinas/efeitos dos fármacos
14.
Regul Pept ; 116(1-3): 35-41, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14599713

RESUMO

The regulation of oxytocin (OT) release by galanin (GAL) at the neurohypophyseal (NH) nerve terminal is not adequately understood. The effect of GAL on the secretion of OT was studied in 13- to 14-day cultures of isolated rat NH tissue. By this time, the hormone content of the medium had become constant. The OT content of the supernatant medium was determined by RIA after a 1- or 2-h incubation. A significantly decreased content of OT was found following incubation with 10(-6)-10(-8) M doses of GAL. Dopamine (DA) and the DA-active drugs apomorphine (APM) and Pro-Lys-Gly (PLG) (10(-6) M in each medium) increased the OT synthesis of NH tissue cultures. This elevation of OT secretion could be blocked by the administration of GAL together with DA, APM or PLG. The DA-blocking effect of GAL was prevented by previous treatment with the GAL receptor antagonist galantid (M15). The results indicate that OT release from the NH is directly influenced by the GAL-ergic system. The GAL-ergic control of OT secretion from NH tissue in rats can occur at the level of the posterior pituitary.


Assuntos
Dopamina/farmacologia , Galanina/farmacologia , Ocitocina/metabolismo , Neuro-Hipófise/efeitos dos fármacos , Neuro-Hipófise/metabolismo , Animais , Relação Dose-Resposta a Droga , Masculino , Neuro-Hipófise/citologia , Ratos , Ratos Wistar
15.
Regul Pept ; 110(1): 17-23, 2002 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-12468105

RESUMO

The effect of galanin (GAL) on vasopressin (VP) secretion was studied in 13-14-day cultures of isolated rat neurohypophyseal (NH) tissue. The VP content of the supernatant was determined by radioimmunoassay (RIA) after a 1- or 2-h incubation. A significantly decreased content of VP was detected following the administration of 10(-6)-10(-9) M doses of GAL. Dopamine (DA) and the DA-active drugs apomorphine (APM) and Pro-Lys-Gly (PLG) (10(-6) M in each medium) increased the VP level of NH tissue cultures. This VP concentration elevation could be blocked by the administration of GAL together with DA, APM or PLG. The DA-blocking effect of GAL was prevented by previous treatment with the GAL receptor antagonist galantid (M15). The results indicate that VP release is directly influenced by the GAL-ergic system. The GAL-ergic control of VP secretion from NH tissue in rats can occur independently of the hypothalamus, at the level of the posterior pituitary.


Assuntos
Antagonistas de Dopamina/farmacologia , Dopamina/farmacologia , Galanina/análogos & derivados , Galanina/farmacologia , Neuro-Hipófise/efeitos dos fármacos , Neuro-Hipófise/metabolismo , Substância P/análogos & derivados , Vasopressinas/metabolismo , Animais , Apomorfina/farmacologia , Técnicas de Cultura , Agonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Galanina/antagonistas & inibidores , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Cinética , Masculino , Radioimunoensaio , Ratos , Ratos Wistar , Receptores de Neuropeptídeos/antagonistas & inibidores , Substância P/farmacologia
16.
J Virol Methods ; 81(1-2): 159-68, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10488774

RESUMO

Twelve single chain variable fragment (scFv) antibodies that bind to particles of Potato leafroll virus (PLRV) were obtained from two naive phage display libraries. Phages were selected against PLRV particles or dissociated PLRV particles immobilised onto tubes. Individual PLRV-binding scFv were identified by ELISA, after their expression either fused to the surface of phage particles, or as soluble scFv (scFv-c-myc), or as scFv-alkaline phosphatase fusion proteins (scFv-AP), obtained by subcloning into pSKAP/S. These procedures resulted in the isolation of scFv with different properties. For example, some of the scFv reacted strongly with virus particles but not with dissociated capsid protein, which suggests that they had reacted with discontinuous epitopes. Others reacted with dissociated capsid proteins and SDS-denatured protein, which suggests that they had reacted with continuous epitopes. ScFv were also subcloned into pC(L) for expression as fusion proteins with human kappa constant region (scFv-C(L)). Expression of these constructs in Escherichia coli yielded 0.2-1 mg protein per litre of bacterial culture. The different scFv fusion proteins were evaluated in ELISA to detect PLRV in leaf extracts of Physalis floridana. Absorbance values obtained with the fusion proteins were greater than those obtained with the scFv-c-myc, and were similar to those obtained in assays done using monoclonal or polyclonal antibodies.


Assuntos
Bacteriófagos/genética , Região Variável de Imunoglobulina/química , Região Variável de Imunoglobulina/genética , Luteovirus/imunologia , Solanum tuberosum/virologia , Fosfatase Alcalina/genética , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos/síntese química , Immunoblotting , Região Variável de Imunoglobulina/biossíntese , Biblioteca de Peptídeos , Folhas de Planta/virologia , Proteínas Recombinantes de Fusão/biossíntese , Análise de Sequência de DNA , Ressonância de Plasmônio de Superfície
17.
J Chromatogr A ; 909(1): 95-109, 2001 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-11218146

RESUMO

Pressurized liquid extraction was combined with in-situ derivatisation to extract polar analytes such as phenols (including chlorophenols) sterols and carboxylic acids from environmental and microbial samples. This one-step protocol uses acetic anhydride as an acetylation agent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) as an silylation agent, and boron trifluoride-methanol, phenyltrimethyl ammoniumhydroxide and trimethyl sulfoniumhydroxide as methylation agents. It results in faster extraction rates and better or comparable extraction efficiencies when compared to classical approaches. The addition of a silylation agent also facilitates the extraction kinetics of analytes not accessible to silylation (e.g. polycyclic aromatic hydrocarbons or alkylbenzenes). This may be attributed to a dissociative action of the agent to weaken analyte-matrix interactions.


Assuntos
Biomassa , Ácidos Carboxílicos/análise , Técnicas de Química Analítica/métodos , Poluentes Ambientais/análise , Fenóis/análise , Esteróis/análise , Acetilação , Cromatografia Gasosa-Espectrometria de Massas , Metilação , Pressão , Silanos/química , Solo/análise
18.
Anal Bioanal Chem ; 355(5-6): 719-20, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15045352

RESUMO

Methods for the on-line chromatographic preconcentration of Cr(III) and Cr(VI) have been developed. Cr(VI) has been preconcentrated on an RP C18 silica based column with tetrabutylammonium-bromide (TBABr) as ion-pairing agent. Specially for Cr(III) a new and effective preconcentration technique based on the sorption of Cr(III)-ions in a C18 column in presence of KH-phthalate has been developed. The efficiency of sample introduction into the atomic emission spectrometer could be improved by hydraulic high pressure nebulization. For the detection of chromium the acetylene/N(2)O flame has been used as a powerful emission spectrometric source. Applying these steps the detection limit (3sigma) could be improved to 25 pg/mL for Cr(III) and to 20 pg/mL for Cr(VI). The method has been applied for the chromium speciation in natural water samples.

19.
Vet Microbiol ; 65(2): 87-101, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10078593

RESUMO

A region of genome from the NADL strain of BVDV corresponding to the coding sequence for the E2 glycoprotein has been molecularly cloned using RT-PCR. The viral cDNA sequence was used to construct vaccinia virus recombinants that expressed either the entire E2 coding sequence or fragments of it. These recombinants were used to immunise mice of three H-2 haplotypes to investigate their ability to elicit a neutralising antibody response against BVDV. Sera from mice immunised with the recombinant expressing full length E2 contained high levels of virus neutralising antibodies that in addition to giving neutralisation of the homologous NADL strain were also able to neutralise the Oregon C24V reference strain. These sera failed to give any neutralisation of the Osloss reference strain providing evidence for the division of BVDV isolates into at least two distinct E2 serotypes. These results were confirmed in gnotobiotic lambs. Expression of E2 fragments revealed the presence of at least two distinct neutralising epitopes, one of which was localised within the carboxy terminal 90 amino acids of the protein.


Assuntos
Anticorpos Antivirais/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Vírus da Diarreia Viral Bovina/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais , Anticorpos Antivirais/imunologia , Sequência de Bases , Bovinos , Vírus da Diarreia Viral Bovina/química , Vírus da Diarreia Viral Bovina/genética , Regulação Viral da Expressão Gênica , Vida Livre de Germes/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Testes de Neutralização/veterinária , Ensaio de Radioimunoprecipitação/veterinária , Análise de Sequência de DNA , Ovinos , Vacinação/veterinária , Vacinas Sintéticas , Vaccinia virus , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
20.
Psychiatry Res ; 13(4): 285-93, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6596586

RESUMO

Nineteen male patients, under 35 years of age, newly admitted with a diagnosis of schizophrenia, were treated with either chlorpromazine or haloperidol at a fixed dosage for 25 days. Both total and free plasma neuroleptic levels were measured using a radioreceptor assay. Clinical response was measured by the Brief Psychiatric Rating Scale (BPRS). On day 25, nonresponders (those with a decrease of less than 8 points on the BPRS) had both total and free plasma neuroleptic levels within the range observed in responders. It is therefore concluded that lack of therapeutic response is generally not due to inadequate plasma drug levels.


Assuntos
Clorpromazina/sangue , Esquizofrenia/sangue , Adulto , Clorpromazina/uso terapêutico , Haloperidol/sangue , Haloperidol/uso terapêutico , Humanos , Cinética , Masculino , Escalas de Graduação Psiquiátrica , Ensaio Radioligante , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico
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