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1.
Water Sci Technol ; 78(7): 1597-1602, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30427800

RESUMO

A study was performed based on the design of a new wastewater treatment plant (WWTP) to be built in Weesp, The Netherlands (about 46,000 Population Equivalents (PE)). The conventional activated sludge plant was considered among the alternatives, with and without primary sedimentation. This pre-treatment technique is considered a sustainability measure as it improves the energy balance of the WWTP. However, at the same time, the question arose about the cost effectiveness of this measure. The scope of the study was to assess whether other sustainability measures (like solar panels) can realise the same level of sustainability with lower costs. The outcome of the study indeed shows that, for a new WWTP, it is considerably cheaper to avoid primary sedimentation and focus on other measures like solar panels instead. This appeared not only to be the case for the scale of WWTP Weesp, but also for WWTPs with capacities higher than 500,000 PE. For existing WWTPs with primary sedimentation, the choice can be different as customisation is necessary.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Países Baixos , Esgotos , Eliminação de Resíduos Líquidos/economia
2.
J Chem Phys ; 146(24): 244311, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28668045

RESUMO

The true global potential energy minimum configuration of the formaldehyde dimer (CH2O)2, including the presence of a single or a double weak intermolecular CH⋯O hydrogen bond motif, has been a long-standing subject among both experimentalists and theoreticians as two different energy minima conformations of Cs and C2h symmetry have almost identical energies. The present work demonstrates how the class of large-amplitude hydrogen bond vibrational motion probed in the THz region provides excellent direct spectroscopic observables for these weak intermolecular CH⋯O hydrogen bond motifs. The combination of concentration dependency measurements, observed isotopic spectral shifts associated with H/D substitutions and dedicated annealing procedures, enables the unambiguous assignment of three large-amplitude infrared active hydrogen bond vibrational modes for the non-planar Cs configuration of (CH2O)2 embedded in cryogenic neon and enriched para-hydrogen matrices. A (semi)-empirical value for the change of vibrational zero-point energy of 5.5 ± 0.3 kJ mol-1 is proposed for the dimerization process. These THz spectroscopic observations are complemented by CCSD(T)-F12/aug-cc-pV5Z (electronic energies) and MP2/aug-cc-pVQZ (force fields) electronic structure calculations yielding a (semi)-empirical value of 13.7 ± 0.3 kJ mol-1 for the dissociation energy D0 of this global potential energy minimum.

3.
Appl Spectrosc ; 63(1): 92-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19146724

RESUMO

Triacetone triperoxide (TATP) has been prepared in order to study the effect of pH and temperature on the reaction kinetics. Raman spectra of liquid mixtures of acetone and hydrogen peroxide were recorded versus time throughout the experiments. The spectral data of the liquid phases indicate that at 25 degrees C the reaction between acetone and hydrogen peroxide proceeds to form intermediates within one day. Based on the assumption that a likely reaction path involves a sequence of reaction steps between acetone and hydrogen peroxide, calculations of Raman spectra were performed using a density functional theory (DFT)/Hartree-Fock approach. It was not possible from this to assess with certainty which intermediate products formed most extensively in an acetone/hydrogen peroxide mixture. However, it was concluded that the most likely reaction mixture is a mixture of the different intermediate products and that the rate determining step is the ring closure. The reaction rate of TATP formation was found to increase with temperature and with sulfuric acid additions to the acetone/hydrogen peroxide mixture. By correlation of the induction time of TATP crystallization against pH it was shown that the reaction rate is first order with respect to the H+ concentration. Raman spectra of the precipitates from mixtures were in agreement with previous studies done for TATP, except in one case in which a crystal crystallized at 343 K had a distinctly different Raman spectrum. Comparison with calculated spectra revealed that the crystal produced could be diacetone diperoxide (DADP) or tetraacetone tetraperoxide (TrATrP). Single crystal X-ray diffraction analyses revealed that the crystal crystallized at 343 K was DADP.

4.
J Phys Chem A ; 110(30): 9500-4, 2006 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-16869701

RESUMO

Furfuryl alcohol (FA) is a promising reactive precursor for new materials. FA reaction mechanisms, that is, self-reactions or cross reactions with other substances, can be studied by vibrational spectroscopy. We present a necessary prerequisite for such studies by a Raman spectroscopic and theoretical study of FA in weakly interacting environments. It is the first study of FA vibrational properties based on density functional theory (DFT/B3LYP), and a recently proposed hybrid approach to the calculation of fundamental frequencies, which also includes an anharmonic contribution. FA occupies five different conformational states, each with more than 5% probability, and two of these dominate at T = 298 K. Excluding one frequency, the remaining ones are predicted as a weighted average over the two dominant conformers to a best RMS error of 8 cm(-1) and are qualitatively assigned. The excluded CH stretching mode is underestimated by 65 cm(-1). This may be due to a combination of an insufficient level of theory and the neglect of Fermi interactions for properly describing this type of mode.


Assuntos
Furanos/química , Teoria Quântica , Conformação Molecular , Análise Espectral Raman , Termodinâmica , Vibração
5.
Appl Spectrosc ; 58(4): 410-3, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15104810

RESUMO

Fourier transform (FT) Raman spectroscopy is applied to a range of phthalate ester plasticizers in pure form as well as in poly(vinyl chloride) (PVC) samples. It is found that phthalate esters as a group can be identified by a set of six characteristic Raman bands. FT-Raman spectra of 22 phthalate esters are given. It is demonstrated that the presence of phthalate esters in PVC products is readily detectable by FT-Raman spectroscopy. By use of proper reference samples quantitative determination of the phthalate ester content becomes possible as well.


Assuntos
Ácidos Ftálicos/análise , Cloreto de Polivinila/química , Análise Espectral Raman/métodos , Dibutilftalato/análise , Dietilexilftalato/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
6.
Inorg Chem ; 42(6): 1901-7, 2003 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-12639123

RESUMO

The dissolution and complex formation of fluoroaluminates in two eutectic alkalifluoride mixtures, NaF-KF (FNAK) and LiF-NaF-KF (FLINAK), have been investigated by Raman, NMR, and thermal analysis. Melting and dissolution took place stepwise. The eutectic alkalifluoride mixtures with minor amounts of dissolved fluoroaluminate salts started melting at around 460 and 740 degrees C for FLINAK and FNAK mixtures, respectively. Total melting/dissolution of mixtures with 9-11 mol % aluminum fluoro salts added took place near 780 degrees C in the FLINAK solvent and at approximately 900 degrees C for FNAK solutions. The solidified melts were characterized by Raman bands at 561 (nu(1)), 391 (nu(2)), and 328 cm(-1) (nu(5)) and a (27)Al NMR chemical shift near 0 ppm originating from isolated AlF(6)(3-) octahedral ions. The Raman and NMR signals due to AlF(6)(3-) were also observed at temperatures where the samples were only partly melted. Upon total melting, a pronounced dissociation of AlF(6)(3-) into AlF(5)(2-) and fluoride ions took place. At even higher temperatures, the equilibrium was displaced in favor of AlF(5)(2-) in the FNAK solvent. The AlF(5)(2-) ion was characterized by an intensive Raman band at 558 cm(-1) and an increasingly positive (27)Al chemical shift with raising temperature, e.g., of 16 ppm at 935 degrees C.

7.
J Natl Cancer Inst ; 93(20): 1541-52, 2001 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-11604477

RESUMO

BACKGROUND: Survivin, a member of the inhibitor of apoptosis (IAP) protein family, is detectable in most types of cancer, and its presence is associated with a poor prognosis. We determined the effects of gene-based therapies that inhibit survivin function in a mouse tumor model. METHODS: Using five to six mice per treatment group, we injected tumors derived from mouse EL-4 thymic lymphoma cells with plasmids encoding antisense survivin, a dominant-negative mutant survivin, and the T-cell costimulator B7-1. Expression of endogenous survivin and the proteins encoded by the injected plasmids were examined by immunohistochemical staining of tumor sections and by western blot and flow cytometry analyses of isolated tumor cells. Tumor growth, the generation of antitumor cytotoxic T-lymphocyte (CTL) activity, apoptosis, and the contribution of leukocyte subsets to antitumor activity were measured. All statistical tests were two-sided. RESULTS: Large (1.0-cm diameter) tumors had approximately 10-fold more survivin than small (0.2-cm diameter) tumors. At 28 days after injection, antisense and dominant-negative mutant survivin plasmids statistically significantly inhibited the growth of both small (P =.006 and P =.0018, respectively) and large (P<.001 for both plasmids) EL-4 tumors compared with tumors injected with empty plasmid. The growth of large tumors was further inhibited by intratumoral injection with antisense survivin and B7-1 (P =.004); thus, inhibition of survivin expression renders large tumors susceptible to B7-1-mediated immunotherapy. Mice whose tumors were completely eradicated by injection of B7-1 remained tumor free for 26 days after re-injection with EL-4 cells (when the experiment ended). Compared with tumors injected with empty plasmid, tumors injected with survivin-based plasmids had increased apoptosis, and animals bearing such tumors generated more antitumor CTLs. CONCLUSION: Intratumoral injection of plasmids that block survivin expression and stimulate the generation of tumor-specific CTLs may be beneficial for the treatment of large lymphomas.


Assuntos
Antígeno B7-1/uso terapêutico , Proteínas Cromossômicas não Histona/fisiologia , DNA Antissenso/uso terapêutico , Terapia Genética , Imunoterapia , Linfoma não Hodgkin/tratamento farmacológico , Proteínas Associadas aos Microtúbulos , Proteínas de Neoplasias/fisiologia , Neoplasias do Timo/terapia , Animais , Anticorpos Monoclonais/administração & dosagem , Apoptose , Antígeno B7-1/administração & dosagem , Proteínas Cromossômicas não Histona/antagonistas & inibidores , Proteínas Cromossômicas não Histona/biossíntese , Proteínas Cromossômicas não Histona/genética , Terapia Combinada , DNA Antissenso/administração & dosagem , DNA Antissenso/genética , Progressão da Doença , Feminino , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Marcação de Genes , Genes Dominantes , Vetores Genéticos/administração & dosagem , Vetores Genéticos/uso terapêutico , Rejeição de Enxerto/imunologia , Proteínas Inibidoras de Apoptose , Injeções Intralesionais , Depleção Linfocítica , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/patologia , Linfócitos do Interstício Tumoral , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/patologia , Linfoma não Hodgkin/terapia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Survivina , Linfócitos T Citotóxicos/imunologia , Neoplasias do Timo/imunologia , Neoplasias do Timo/patologia
8.
J Pharmacol Exp Ther ; 298(2): 477-84, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11454908

RESUMO

Chemotherapeutic agents targeting thymidylate synthase (TS) are effective against human tumors. Efficacy is limited by drug resistance, often mediated by TS overexpression. Treatment of HeLa cells in vitro with an antisense oligodeoxynucleotide (ODN 83) targeting human TS mRNA reduces TS mRNA and protein levels, inhibits cell proliferation, and sensitizes cells to TS-targeting drugs (Ferguson et al., 1999). The present study investigates the mechanism by which ODN 83 inhibits cell proliferation and examines its antitumor efficacy in vivo. ODN 83 treatment did not induce apoptosis in HeLa cells in vitro but caused accumulation of cells at G2/M. In contrast, TS-targeting chemotherapeutics arrest at G1 or S. Antisense down-regulation reduced TS mRNA levels in human colon cancer (HT29) cells by 40% in vitro, resulted in G2/M arrest, and reduced proliferation without enhanced cell death. Growth of HT29 tumors in immunocompromised mice was significantly inhibited when antisense ODN 83 treatment began promptly after tumor implantation and was accompanied by a 40% reduction in TS protein levels. Growth of tumors allowed to reach 400 mm3 prior to ODN administration was unaffected by antisense ODN 83. Radiolabeled ODNs were localized to the tumor periphery but evenly distributed in normal tissue. Thus, down-regulation of TS mRNA and protein by antisense ODN treatment exerts a novel G2/M cell cycle block without increasing cell death and inhibits HT29 tumor cell growth in vivo. Antisense ODN 83 may be an effective therapy for colon carcinoma, alone or in combination with TS-targeting cytotoxic drugs.


Assuntos
Antineoplásicos/farmacologia , Oligonucleotídeos Antissenso/farmacologia , Timidilato Sintase/genética , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Citometria de Fluxo , Células HT29 , Células HeLa , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
9.
Cancer Gene Ther ; 8(12): 974-81, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11781660

RESUMO

Heat shock proteins (hsps) chaperone cytosolic peptides, forming complexes that stimulate antitumor immunity. Hsps facilitate signal 1 in the two-signal model of T-cell costimulation, whereas cell adhesion molecules such as B7.1 provide secondary (signal 2) costimulatory signals. B7.1 gene transfer into tumors in situ has been shown to eradicate small (<0.3 cm in diameter) tumors in mice, and induce systemic antitumor immunity, but is ineffective against larger tumors. We examine whether mammalian hsps, as facilitators of T-cell costimulation, also exhibit this ability, and whether simultaneously stimulating both signal 1 (hsp-facilitated antigen presentation) and signal 2 (B7.1-mediated costimulation) enhances antitumor immunity compared to that achieved with either monotherapy. Prophylactic vaccination of mice with an hsp preparation from an EL-4 lymphoma weakly retarded tumor growth, to the same extent as that achieved with a single EL-4-derived peptide (AQHPNAELL), previously shown to induce antitumor immunity establishing that a preparation of EL-4 hsp-peptide complexes has antitumor activity. Here we show that injection of rat hsp70.1 into mouse tumors in situ causes the complete eradication of tumors, and generates potent systemic antitumor immunity mediated by CD4+ and CD8+ T cells. Unexpectedly, simultaneous gene transfer of hsp70.1 and B7.1 compromised the efficacy of hsp-mediated tumor rejection--a problem which could be partially overcome by the timed delivery of hsp70.1 and B7.1. Thus, gene transfer of hsp70 into tumors can be employed to generate potent systemic antitumor immunity, but further consideration is required if this approach is to be successfully combined with immunotherapies employing other T-cell costimulators.


Assuntos
Antígeno B7-1/genética , Citotoxicidade Imunológica/genética , Proteínas de Choque Térmico HSP70/genética , Imunoterapia , Proteínas de Protozoários/genética , Animais , Apresentação de Antígeno/genética , Apresentação de Antígeno/imunologia , Antígeno B7-1/imunologia , Terapia Genética , Proteínas de Choque Térmico HSP70/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Protozoários/imunologia , Ratos , Linfócitos T/imunologia , Transfecção , Células Tumorais Cultivadas
10.
J Hosp Infect ; 45(1): 29-34, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10917779

RESUMO

In the first week ot December 1997, an increasing incidence of neonates colonized with multi-drug resistant Enterobacter cloacae (MR-E. cloacae) was observed in the neonatal Intensive care unit of our 950-bed university hospital. Initially, re-enforcement of infection control practices including hand disinfection and cohort isolation seemed to be sufficient to control the outbreak. Nevertheless, an increasing number of newly admitted patients was paralleled by another rise in the incidence of colonized neonates. Since E. cloacae was initially found in urine specimens of the patients, surveillance and environmental cultures were aimed at procedures and instruments that might colonize the gastro-intestinal and/or urinary tract. E, cloacae was isolated from a single cap of an electronic digital thermometer. Despite banning of this possible source, newly admitted neonates still became colonized. The unit was closed for further admissions and a second round of extensive screening was started; this time including all available thermometers and continuous rectal temperature probes. Ready-to-use 'disinfected thermometers and probes were found to be colonized with MR-E. cloacae. Observation of disinfection procedures and a laboratory investigation revealed that 'rushed disinfection with alcohol 80% led to a 1 in 10 chance of thermometers still being contaminated. Furthermore, alcoholic hand rub used for convenience disinfection failed to disinfect thermometers in 40% and 20% of the cases when done in a 'rushed' or 'careful' fashion, respectively. Adequate disinfection of the thermometers led to the control of the outbreak, with no new occurrence of MR-E. cloacae in the following months.


Assuntos
Surtos de Doenças , Enterobacter cloacae , Infecções por Enterobacteriaceae/etiologia , Unidades de Terapia Intensiva Neonatal , Termômetros/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Infecção Hospitalar/prevenção & controle , Impressões Digitais de DNA , Enterobacter cloacae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/prevenção & controle , Contaminação de Equipamentos/prevenção & controle , Humanos , Técnicas In Vitro , Incidência , Recém-Nascido , Países Baixos/epidemiologia , Fatores de Risco
11.
Inorg Chem ; 39(16): 3449-54, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11196801

RESUMO

A vacuum-tight cell for infrared spectroscopic investigations of extremely corrosive melts, e.g., molten fluorides, has been constructed and tested up to 750 degrees C. The cell has a gold-lined sample chamber and a diamond window transparent for the infrared light. It can be furnished with a gold piston that enables the recording of short-path-length FTIR spectra of liquid samples. Solutions of Nb(V) in LiF-NaF-KF eutectic (FLINAK) with and without oxide additions have been investigated by FTIR and Raman spectroscopy. The presence of NbF7(2-), NbOF5(2-), and NbO2F4(3-) complexes was established in the molten state at 600 degrees C. After solidification NbF7(2-) was still the only Nb(V) all-fluoro complex present. Three oxofluoro complexes, NbOF6(3-), NbOF5(2-), and NbO2F4(3-), have been identified in the solid state. Typical frequency regions for the different complexes are established. Finally, it was shown that K2NbF7 can be used as an indicator to determine the oxide content of the sample melts.

12.
Inorg Chem ; 39(16): 3682-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11196833

RESUMO

Raman spectra have been obtained for matrix-isolated AlF6(3-) in an LiF/NaF/KF (FLINAK) eutectic mixture. Three Raman bands characteristic of the hexafluoroaluminate ion were identified in the solids formed from FLINAK melts which contained small amounts (5-11 mol%) of either AlF3 or Na3AlF6. The three allowed Raman-active bands of the matrix-isolated octahedral complex ion, nu 1(A1g), nu 2(Eg), and nu 5(F2g), were observed at 560.5, 380, and 325 cm-1, respectively, for the solid sample at 25 degrees C. Wavenumbers and relative intensities were similar to those of Na3AlF6 (cryolite), K3AlF6, and K2NaAlF6 (elpasolite) and other crystals known to contain discrete, octahedral AlF6(3-) ions. Peak positions, half-widths, and relative intensities for the bands were measured for samples at temperatures different from room temperature through the melting transition and into the molten state. The transition from high-temperature solid to molten salt at about 455 degrees C occurred gradually without perceptible change in the peak positions, half-widths, or relative intensities. For a sample in molten FLINAK at 455 degrees C, the nu 1(A1g), nu 2(Eg), and nu 5(F2g) modes of the AlF6(3-) ion were observed at 542, 365, and 324 cm-1, respectively. Raman depolarization experiments were consistent with these assignments, and the low value of the depolarization ratio of the nu 1(A1g) mode at 542 cm-1 indicated that the sample was molten above 455 degrees C. Differential thermal analysis also indicated that the FLINAK samples melted at about 455 degrees C. Raman measurements were performed for samples at temperatures from 25 to 600 degrees C in a silver dish, on a hot stage, in an argon-filled atmosphere, under a microscope. Additional Raman experiments were performed on samples at temperatures from 25 to 750 degrees C in a conventional graphite windowless cell, in an argon-filled quartz tube, in a standard furnace. Over the concentration range 4.8-11 mol% AlF3 (CR 23-8.0) in FLINAK, only bands due to the AlF6(3-) ion were detected. There was no evidence to support the presence of other aluminum complexes in these melts.

13.
Inorg Chem ; 39(21): 4725-30, 2000 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-11196946

RESUMO

A Raman spectrum consistent with that expected from an Al2OF6(2-) ion was observed when Na2O was dissolved in a eutectic LiF/NaF/KF (FLINAK) melt at 500 degrees C, which contained a low concentration of either AlF3 or Na3AlF6. Furthermore, it was possible to trap the Al2OF6(2-) ion in the frozen solid and to measure its Raman and IR spectra at 25 degrees C. A number of bands have been detected; among those, the two most characteristic bands of the Al2OF6(2-) ion at 494 (polarized) and 265 cm-1 in the FLINAK melt at 500 degrees C, and those at 509 and 268 (Raman) and approximately 780 to approximately 900 (IR) cm-1 for the compound matrix isolated in solid FLINAK at 25 degrees C. In the absence of added oxide, the dissolved aluminum fluoride was in the form of the octahedral AlF6(3-) ion, which has characteristic Raman bands at 542 and 325 cm-1 in the FLINAK melt at 500 degrees C. Whereas alumina, Al2O3, was found to be essentially insoluble in FLINAK melts, it was possible to dissolve sufficient amounts of Na2O to convert most of the AlF6(3-) to the oxyfluoroaluminate, Al2OF6(2-). These solutions appeared to be metastable with respect to formation of insoluble alumina at higher temperatures. The present results can be compared to previous measurements on alumina dissolved in pure molten cryolite at much higher temperatures, where alumina solubility is low and broad bands due to oxide species are difficult to detect due to overlap with bands from AlF6(3-) and AlF4-.

14.
Eur J Immunol ; 29(9): 2875-85, 1999 09.
Artigo em Inglês | MEDLINE | ID: mdl-10508262

RESUMO

Here we report that an activator (AIF4-) of heterotrimeric GTP-binding proteins (G-proteins) and inhibitors (lovastatin and C3 exoenzyme) of small GTP-binding proteins regulate the induction of alpha4beta7-mediated adhesion of TK-1 T lymphoma cells (alpha4+beta7+beta1-) to the mucosal addressin cell adhesion molecule MAdCAM-1. Activation of cell adhesion by AIF4- was abrogated by lovastatin, thereby establishing a link between heterotrimeric G-proteins and small GTP-binding proteins in the regulation of alpha4beta7-mediated cell adhesion. Increased numbers of cells bound MAdCAM-1-coated microspheres following activation with AIF4-, discounting an obligatory role for cell spreading in alpha4beta7-mediated cell adhesion. MAdCAM-1-Fc dimers triggered ligand-induced clustering of alpha4beta7 in response to AIF4- and Mn2+-induced activation of integrins. Hence alpha4beta7 cluster formation may be responsible, at least in part, for inducing cell adhesion in response to both extracellular and intracellular signals that impact on integrin function. Electroporation of constitutively active V14RhoA and V12Rac1 recombinant proteins into TK-1 cells revealed that both RhoA and Rac1 induce alpha4beta7 adhesion to MAdCAM-1. Activation is hierarchical since Rac1 is unable to directly activate alpha4beta7, but induces cell adhesion via RhoA, whereas the transient induction of cell adhesion mediated by RhoA is dependent on the activities of protein tyrosine kinases and protein kinase(s) C.


Assuntos
Imunoglobulinas/imunologia , Mucoproteínas/imunologia , Linfócitos T/imunologia , Proteínas rac de Ligação ao GTP/imunologia , Proteínas rho de Ligação ao GTP/imunologia , Células 3T3 , Compostos de Alumínio/farmacologia , Animais , Adesão Celular/imunologia , Moléculas de Adesão Celular , Complemento C3/fisiologia , Eletroporação , Fluoretos/farmacologia , Genisteína/farmacologia , Integrinas/análise , Integrinas/imunologia , Integrinas/metabolismo , Linfoma de Células T , Camundongos , Receptores de Retorno de Linfócitos/imunologia , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologia , Células Tumorais Cultivadas , Proteínas rac de Ligação ao GTP/genética , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo
15.
Somatosens Mot Res ; 16(2): 69-88, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10449057

RESUMO

An accumulation of anatomical, behavioral, and electrophysiological evidence allows us to identify the neuronal circuitry that is involved with vibrissa-mediated sensation and the control of rhythmic vibrissa movement. Anatomical evidence points to a multiplicity of closed sensorimotor loops, while electrophysiological data delineate the flow of electrical signals in these pathways. These loops process sensory input from the vibrissae and send projections to direct vibrissa movement, starting at the level of the hindbrain and proceeding toward loops that involve multiple structures in the forebrain. The nature of the vibrissa-related electrical signals in behaving animals has been studied extensively at the level of neocortical loops. Two types of spike signal are observed that serve as a reference of vibrissa motion: a fast signal that correlates with the relative phase of the vibrissae within a whisk cycle and a slow signal that correlates with the amplitude, and possibly the set-point, of the vibrissae during a whisk. Both signals are observed in vibrissa primary sensory (S1) cortex, and in some cases they are sufficiently robust to allow vibrissa position to be accurately estimated from the spike train of a single neuron. Unlike the case for S1 cortex, only the slow signal has been observed in vibrissa primary motor (M1) cortex. The control capabilities of M1 cortex were estimated from experiments with anesthetized animals in which progressive areas along the vibrissa motor branch were microstimulated with rhythmically applied currents. The motion of the vibrissae followed stimulation of M1 cortex only for rates that were well below the frequency of rhythmic whisking; in contrast, the vibrissae followed stimulation of the facial nucleus, whose cells directly drive the vibrissae, for rates above that of whisking. In toto, the evidence implies that there is fast signaling from the facial nucleus, through the mystacial pad and the vibrissae and up through sensory cortex, but only slow signaling at the level of the motor cortex and down through the superior colliculus to the facial nucleus. The transformation from fast sensory signals to slow motor control is an unresolved issue. On the other hand, there is a candidate scheme to understand how the fast reference of vibrissa motion in the whisk cycle may be used to decode the angle of the vibrissae upon their contact with an object. We discuss a circuit in which servo mechanisms are used to determine the angle of contact relative to the preferred phase of the fast reference signals. Support for this scheme comes from results with anesthetized animals on the frequency and phase entrainment of intrinsic neuronal oscillators in S1 cortex. A prediction based on this scheme is that the output from a decoder circuit is maximal when the angle of contact differs from the preferred phase of a fast regerence signal. In contrast, for correlation-based schemes the output is maximal when the angle of contact equals the preferred phase.


Assuntos
Comportamento Animal/fisiologia , Eletrofisiologia , Rede Nervosa/fisiologia , Vibrissas/inervação , Animais , Córtex Motor/fisiologia , Ratos , Córtex Somatossensorial/fisiologia
16.
Immunol Cell Biol ; 77(4): 337-44, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10457201

RESUMO

Human mucosal lymphocyte antigen-1 (HML-1, alphaEbeta7) and E-cadherin, two members of unrelated cell adhesion superfamilies, have evolved to play cooperative roles in gut mucosal immunity. Human E-cadherin is self-ligand mediating intercellular adhesion of epithelial cells, as well as adhesion of intra-epithelial lymphocytes to intestinal enterocytes via an interaction with HML-1. Herein we report that both dimeric and monomeric forms of recombinant mouse E-cadherin-human immunoglobulin Fc chimera self-associate and support attachment of E-cadherin+ mouse colon epithelial cells. Both forms also support the adhesion of mouse MTC-1 T cells via M290, thereby establishing M290 as the functional mouse homologue of HML-1 and revealing that E-cadherin homophilic and heterophilic binding sites are distinct. Adhesion of MTC-1 cells to E-cadherin-Fc was inhibited by arginine-glycine-aspartate (RGD) peptides and vice versa cells bound to immobilized RGD polymer in an M290-dependent fashion, where adhesion was inhibitable with soluble E-cadherin-Fc. Hence, E-cadherin and RGD integrin ligands antagonize cell binding by one another, either by inducing integrin cross-talk or by binding to shared or overlapping sites within M290. Binding of E-cadherin-Fc by HML-1 costimulated the CD3-induced proliferation of purified CD4+ T cells, suggesting that E-cadherin expressed on dendritic cells may play a T cell costimulatory role in addition to facilitating dendritic cell-keratinocyte adhesion.


Assuntos
Caderinas/imunologia , Integrinas/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Caderinas/química , Caderinas/genética , Neoplasias do Colo/imunologia , Primers do DNA/genética , Dimerização , Humanos , Imunidade nas Mucosas , Integrinas/química , Integrinas/genética , Ligantes , Ativação Linfocitária , Camundongos , Dados de Sequência Molecular , Oligopeptídeos , Conformação Proteica , Linfócitos T/imunologia , Células Tumorais Cultivadas
17.
Genomics ; 56(2): 169-78, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10051402

RESUMO

Herein we describe the cDNA sequence of a novel human gene, ITGBL1, encoding a beta integrin-related protein termed TIED [for ten beta integrin epidermal growth factor (EGF)-like repeat domains]. Overlapping cDNA clones from fetal lung, HUVEC, and osteoblast cDNA libraries encode a sequence comprising a typical signal peptide, followed by a hydrophilic 471-amino-acid domain containing 10 tandem EGF-like repeats strikingly similar to those found in the cysteine-rich "stalk-like" structure of integrin beta subunits. The EGF-like repeats of TIED and beta integrins are unique in that they alternate in homology and possess two additional cysteines (eight in total) whose positions differ from those in the other eight-cysteine EGF-like domains of laminin, fibrillin, and the latent TGF-beta binding proteins. TIED mRNA transcripts of 2.8 kb were detected in aorta, thymus, and osteogenic sarcoma cells. The ITGBL1 gene was mapped to human chromosome 13, band 13q33. We suggest that ITGBL1 may be linked in some way with the evolution of the integrin beta subunits.


Assuntos
Cromossomos Humanos Par 13/genética , DNA Complementar/genética , Integrinas/genética , Regiões 3' não Traduzidas , Processamento Alternativo , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Bandeamento Cromossômico , Mapeamento Cromossômico , Clonagem Molecular , DNA Complementar/química , Fator de Crescimento Epidérmico , Regulação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Integrinas/química , Dados de Sequência Molecular , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Células Tumorais Cultivadas
18.
Immunogenetics ; 46(2): 111-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9162097

RESUMO

MAdCAM-1, the endothelial addressin cell adhesion molecule-1, interacts preferentially with the leukocyte beta7 integrin LPAM-1 (alpha4beta7), but also with L-selectin, and with VLA-4 (alpha4beta1) on myeloid cells, and serves to direct leukocytes into mucosal and inflamed tissues. Overlapping cosmid and phage lambda genomic clones were isolated, revealing that the human MAdCAM-1 gene contains five exons where the signal peptide, two Ig domains, and mucin domain are each encoded by separate exons. The transmembrane domain, cytoplasmic domain, and 3' untranslated region are encoded together on exon 5. The mucin domain contains eight repeats in total that are subject to alternative splicing. Despite the absence of a human counterpart of the third IgA-homologous domain and lack of sequence conservation of the mucin domain, the genomic organizations of the human and mouse MAdCAM-1 genes are similar. An alternatively spliced MAdCAM-1 variant was identified that lacks exon 4 encoding the mucin domain, and may mediate leukocyte adhesion to LPAM-1 without adhesion to the alternate receptor, L-selectin. The MAdCAM-1 gene was located at p13.3 on chromosome 19, in close proximity to the ICAM-1 and ICAM-3 genes (p13.2-p13.3). PMA-inducible promotor activity was contained in a 700 base pair 5' flanking fragment conserved with the mouse MAdCAM-1 gene including tandem NF-kB sites, and an Sp1 site; and in addition multiple potential AP2, Adh1 (ETF), PEA3, and Sp1 sites. In summary, the data establish that the previously reported human MAdCAM-1 cDNA does indeed encode the human homologue of mouse MAdCAM-1, despite gross dissimilarities in the MAdCAM-1 C-terminal structures.


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 19 , Genoma Humano , Imunoglobulinas/genética , Mucoproteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Moléculas de Adesão Celular , Clonagem Molecular , Humanos , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Receptores de Retorno de Linfócitos/genética
19.
Infect Dis Obstet Gynecol ; 5(3): 252-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18476146

RESUMO

OBJECTIVE: The goals of this study were 1) to better define the labial microflora and 2) to evaluate whether extended non-menstrual use of panty liners would increase genital carriage of undesirable bacteria and predispose to infection. METHODS: Healthy female volunteers (224) were prospectively randomized into panty liner wear groups A (Always((R)) deodorant) and B (Always((R)) non-deodorant) and into a control group C (no panty liner wear) with instructions for non-menstrual +/- menstrual use >/=5 h daily for 6 months. Selected aerobic bacteria were semiquantitatively cultured from the inner labial groove, the posterior fornix of the vagina, and the cervix pre-study and post-study. Used panty liners were quantitatively cultured, and vaginal secretions were examined by gas chromatography for fatty acid ratios as a measure of microbial flora shifts. RESULTS: At the pre-study, labial microflora in this study population contained significantly higher frequencies of Staphylococcus, coliforms, other gram-negative rods, and enterococci, and a decreased frequency of Gardnerella vaginalis relative to the vaginal microflora. After 6 months use of panty liners the frequencies (and densities) of the selected microorganisms in these two sites had not changed compared to controls, and fatty acid analyses of vaginal secretions gave no evidence of shifts in the microbial flora. CONCLUSIONS: Frequencies of selected genital microflora were different for the labia compared to the vagina. No increased carriage of medically important species was detected for either site after 6 months of daily (average 7.8 h) panty liner use.

20.
Gynecol Obstet Invest ; 44(4): 260-4, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9415525

RESUMO

Methods are described for assessing the gynecologic, dermatologic, and microbiologic effects of deodorant and non-deodorant catamenial pad use over a 6-month period. A controlled, randomized, investigator-blind parallel study was conducted with 190 women between the ages of 18 and 45 years. Data on medical histories, physical examinations, diagnostic laboratory tests, gynecologic and dermatologic examinations and microbiology were collected. No significant differences in gynecologic, dermatologic, or microbiologic parameters were observed between control and treated groups, and no pad-related adverse health effects were observed in this clinical study.


Assuntos
Menstruação , Tampões Cirúrgicos/efeitos adversos , Adolescente , Adulto , Dermatite Alérgica de Contato/etiologia , Técnicas de Diagnóstico Obstétrico e Ginecológico , Método Duplo-Cego , Feminino , Seguimentos , Virilha , Humanos , Higiene , Pessoa de Meia-Idade , Exame Físico , Segurança , Vagina/microbiologia , Doenças Vaginais/microbiologia
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