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1.
Phys Rev Lett ; 125(26): 262301, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449792

RESUMO

Flow coefficients v_{n} of the orders n=1-6 are measured with the High-Acceptance DiElectron Spectrometer (HADES) at GSI for protons, deuterons, and tritons as a function of centrality, transverse momentum, and rapidity in Au+Au collisions at sqrt[s_{NN}]=2.4 GeV. Combining the information from the flow coefficients of all orders allows us to construct for the first time, at collision energies of a few GeV, a multidifferential picture of the angular emission pattern of these particles. It reflects the complicated interplay between the effect of the central fireball pressure on the emission of particles and their subsequent interaction with spectator matter. The high precision information on higher order flow coefficients is a major step forward in constraining the equation of state of dense baryonic matter.

2.
BMC Microbiol ; 19(1): 132, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31195965

RESUMO

BACKGROUND: Xenorhabdus spp. live in close symbiosis with nematodes of the Steinernema genus. Steinernema nematodes infect an insect larva and release their symbionts into the haemocoel of the insect. Once released into the haemocoel, the bacteria produce bioactive compounds to create a semi-exclusive environment by inhibiting the growth of bacteria, yeasts and molds. The antimicrobial compounds thus far identified are xenocoumacins, xenortides, xenorhabdins, indole derivatives, xenoamicins, bicornutin and a number of antimicrobial peptides. The latter may be linear peptides such as the bacteriocins xenocin and xenorhabdicin, rhabdopeptides and cabanillasin, or cyclic, such as PAX lipopeptides, taxlllaids, xenobactin and szentiamide. Thus far, production of antimicrobial compounds have been reported for Xenorhabdus nematophila, Xenorhabdus budapestensis, Xenorhabdus cabanillasii, Xenorhabdus kozodoii, Xenorhabdus szentirmaii, Xenorhabdus doucetiae, Xenorhabdus mauleonii, Xenorhabdus indica and Xenorhabdus bovienii. Here we describe, for the first time, PAX lipopeptides and xenocoumacin 2 produced by Xenorhabdus khoisanae. These compounds were identified using ultraperformance liquid chromatography, linked to high resolution electrospray ionisation mass spectrometry and tandem mass spectrometry. RESULTS: Cell-free supernatants of X. khoisanae SB10 were heat stable and active against Bacillus subtilis subsp. subtilis, Escherichia coli and Candida albicans. Five lysine-rich lipopeptides from the PAX group were identified in HPLC fractions, with PAX1' and PAX7 present in the highest concentrations. Three novel PAX7 peptides with putative enoyl modifications and two linear analogues of PAX1' were also detected. A small antibiotic compound, yellow in colour and λmax of 314 nm, was recovered from the HPLC fractions and identified as xenocoumacin 2. The PAX lipopeptides and xenocoumacin 2 correlated with the genes and gene clusters in the genome of X. khoisanae SB10. CONCLUSION: With UPLC-MS and MSe analyses of compounds in the antimicrobial complex of X. khoisanae SB10, a number of PAX peptides and a xenocoumacin were identified. The combination of pure PAX1' peptide with xenocoumacin 2 resulted in high antimicrobial activity. Many of the fractions did, however, contain labile compounds and some fractions were difficult to resolve. It is thus possible that strain SB10 may produce more antimicrobial compounds than reported here, as suggested by the APE Ec biosynthetic complex. Further research is required to develop these broad-spectrum antimicrobial compounds into drugs that may be used in the fight against microbial infections.


Assuntos
Anti-Infecciosos/farmacologia , Benzopiranos/farmacologia , Lipopeptídeos/metabolismo , Xenorhabdus/fisiologia , Anti-Infecciosos/metabolismo , Bacillus subtilis/efeitos dos fármacos , Proteínas de Bactérias , Benzopiranos/metabolismo , Vias Biossintéticas , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Escherichia coli/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray , Simbiose , Espectrometria de Massas em Tandem , Xenorhabdus/genética , Xenorhabdus/metabolismo
3.
Phys Rev Lett ; 123(2): 022002, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386541

RESUMO

We present the first observation of K^{-} and ϕ absorption within nuclear matter by means of π^{-}-induced reactions on C and W targets at an incident beam momentum of 1.7 GeV/c studied with HADES at SIS18/GSI. The double ratio (K^{-}/K^{+})_{W}/(K^{-}/K^{+})_{C} is found to be 0.319±0.009(stat)_{-0.012}^{+0.014}(syst) indicating a larger absorption of K^{-} in heavier targets as compared to lighter ones. The measured ϕ/K^{-} ratios in π^{-}+C and π^{-}+W reactions within the HADES acceptance are found to be equal to 0.55±0.04(stat)_{-0.07}^{+0.06}(syst) and to 0.63±0.06(stat)_{-0.11}^{+0.11}(syst), respectively. The similar ratios measured in the two different reactions demonstrate for the first time experimentally that the dynamics of the ϕ meson in nuclear medium is strongly coupled to the K^{-} dynamics. The large difference in the ϕ production off C and W nuclei is discussed in terms of a strong ϕN in-medium coupling. These results are relevant for the description of heavy-ion collisions and the structure of neutron stars.

4.
Osteoarthritis Cartilage ; 26(8): 1110-1117, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29803826

RESUMO

OBJECTIVES: The chondrocytes' pericellular matrix acts as a mechanosensor by sequestering growth factors that are bound to heparan sulfate (HS) proteoglycans. Heparanase is the sole mammalian enzyme with HS degrading endoglycosidase activity. Here, we aimed to ascertain whether heparanase plays a role in modulating the anabolic or catabolic responses of human articular chondrocytes. METHODS: Primary chondrocytes were incubated with pro-heparanase and catabolic and anabolic gene expression was analyzed by quantitative polymerase chain reaction (PCR). MMP13 enzymatic activity in the culture medium was measured with a specific fluorescent assay. Extracellular regulated kinase (ERK) phosphorylation was evaluated by Western blot. Human osteoarthritis (OA) cartilage was assessed for heparanase expression by reverse-transcriptase PCR, by Western blot and by a heparanase enzymatic activity assay. RESULTS: Cultured chondrocytes rapidly associated with and activated pro-heparanase. Heparanase induced the catabolic genes MMP13 and ADAMTS4 and the secretion of active MMP13, and down-regulated the anabolic genes ACAN and COL2A1. PG545, a HS-mimetic, inhibited the effects of heparanase. Heparanase expression and enzymatic activity were demonstrated in adult human osteoarthritic cartilage. Heparanase induced ERK phosphorylation in cultured chondrocytes and this could be inhibited by PG545, by fibroblast growth factor 2 (FGF2) neutralizing antibodies and by a FGF-receptor inhibitor. CONCLUSIONS: Heparanase is active in osteoarthritic cartilage and induces catabolic responses in primary human chondrocytes. This response is due, at least in part, to the release of soluble growth factors such as FGF2.


Assuntos
Cartilagem Articular/enzimologia , Condrócitos/enzimologia , Glucuronidase/metabolismo , Osteoartrite/enzimologia , Adulto , Western Blotting , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Condrócitos/metabolismo , Humanos , Metaloproteinase 13 da Matriz/metabolismo , Osteoartrite/metabolismo , Osteoartrite/patologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Pathologe ; 36(5): 477-84, 2015 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-26280511

RESUMO

Macrophages are important factors in the pathogenesis and prognosis of malignant tumors and represent a possible target for therapeutic intervention. Depending on the tumor entity and the prevalent polarization status, macrophages can be associated with a favorable or unfavorable clinical outcome. It is becoming clear, however, that the conventional definitions of M1 polarized tumor inhibitory and M2 polarized tumor promoting macrophages do not adequately reflect the heterogeneity and plasticity of macrophages. Macrophages can support tumor growth through direct interactions with the neoplastic cells, by promoting tissue remodeling and angiogenesis and by inhibiting local immune reactions. To achieve comparability of clinical studies, it will be necessary to reach a consensus nomenclature of macrophage polarization. Furthermore, methods for the quantitative characterization of macrophage populations in malignant tumors will have to be standardized. It is unlikely that single marker immunohistochemistry will be adequate in this context. In any case it is necessary to provide unequivocal information regarding the markers or marker combinations used.


Assuntos
Diferenciação Celular/fisiologia , Macrófagos/patologia , Macrófagos/fisiologia , Neoplasias/patologia , Neoplasias/fisiopatologia , Plasticidade Celular/fisiologia , Polaridade Celular/fisiologia , Humanos , Tolerância Imunológica/fisiologia , Macrófagos/classificação , Neoplasias/irrigação sanguínea , Neoplasias/imunologia , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia
6.
Ann Oncol ; 25(10): 2042-2047, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25057171

RESUMO

BACKGROUND: The prognostic role of persistence of circulating tumor cells (CTC) after upfront tumor surgery for outcome of adjuvant (chemo)radiation in locally advanced squamous cell carcinoma of the head and neck (LASCCHN) was evaluated. PATIENTS AND METHODS: In this prospective study, peripheral blood samples from 144 patients with LASCCHN presenting after tumor resection for adjuvant treatment were analyzed for CTC. Their detection was correlated with tumor site, clinical risk factors, disease-free (DFS) and overall survival (OS). RESULTS: CTC were detected in 42 of 144 patients (29%). CTC detection was higher in cases with nodal involvement and in carcinomas located at the tonsil or base of tongue but was not influenced by age, smoking history, T stage, extracapsular lymph node extension, surgical margins or the human papillomavirus status. Overall, the presence of CTC was not predictive for OS or DFS. However, while in oropharyngeal carcinomas (OPC, n = 63), the detection of CTC was associated per trend with improved DFS [CTC+ versus CTC- (% of patients without evidence of disease at 2 years): 100% versus 79%; log rank: P = 0.059]; the reverse was observed for carcinomas from other sites (non-OPC, n = 81; CTC+ versus CTC-: 29% versus 75%; P = 0.001). In multivariate analysis, CTC remained an independent prognostic marker for DFS [hazard ratio (HR) 4.3, 95% confidence interval (CI) 1.7-10.9, P = 0.002] and OS (HR 2.7, 95% CI 1.2-6.3, P = 0.016) in non-OPC. CONCLUSIONS: Assessment of CTC in non-OPC should prove useful for identification of patients who benefit from treatment intensification. The basis for the good prognostic value of CTC in OPC has to be elucidated in future studies.


Assuntos
Quimiorradioterapia Adjuvante , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Células Neoplásicas Circulantes/patologia , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas , Terapia Combinada , Intervalo Livre de Doença , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células Epiteliais/efeitos da radiação , Feminino , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Células Neoplásicas Circulantes/efeitos dos fármacos , Células Neoplásicas Circulantes/efeitos da radiação , Estudos Prospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
7.
J Chem Phys ; 141(22): 22D521, 2014 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-25494792

RESUMO

Chloride anions permeate the bacterial NanC porin in physiological processes. Here we present a DFT-based QM/MM study of this porin in the presence of these anions. Comparison is made with classical MD simulations on the same system. In both QM/MM and classical approaches, the anions are almost entirely solvated by water molecules. However, the average water-Cl(-) distance is significantly larger in the first approach. Polarization effects of protein groups close to Cl(-) anion are sizeable. These effects might modulate the anion-protein electrostatic interactions, which in turn play a central role for selectivity mechanisms of the channel.


Assuntos
Proteínas da Membrana Bacteriana Externa/química , Cloretos/química , Proteínas de Escherichia coli/química , Escherichia coli/química , Porinas/química , Água/química , Sítios de Ligação , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Teoria Quântica , Termodinâmica
8.
Surgeon ; 8(1): 20-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20222399

RESUMO

Professionalism has been identified as one of four domains of competency for surgical trainees in the UK. This implies that professionalism can be learned and assessed. The priorities of different professions and healthcare systems influence the value placed on different components of professionalism and UK surgeons need to identify the characteristics they would most value as part of an effective assessment process. The success of developing a taxonomy of non-technical skills for surgeons (NOTSS) can guide a similar process for a taxonomy for professionalism assessment. A multitude of assessment instruments for professionalism have been described in the literature but very few are valid, reliable or practical. For surgical trainees a number of assessment tools should be considered. A quantifiable tool using multi-source feedback could be the most practical for clinical surgeons to use. It is important, however, that it is not used to assess isolated behaviours but assess conduct within a surgical community of practice, and that the thinking process behind (un)professional behaviour is also understood, especially in stressful situations.


Assuntos
Competência Clínica/normas , Cirurgia Geral/normas , Médicos/normas , Especialidades Cirúrgicas/normas , Atitude do Pessoal de Saúde , Avaliação Educacional , Avaliação de Desempenho Profissional , Humanos
9.
Neuroscience ; 159(1): 47-58, 2009 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-19135135

RESUMO

Multiple theories have been proposed for sensation seeking and vulnerability to impulse-control disorders [Zuckerman M, Kuhlman DM (2000) Personality and risk-taking: Common biosocial factors. J Pers 68:999-1029], and many of these rely on a dopamine system deficit. Available animal models reproduce only some behavioral symptoms and seem devoid of construct validity. We used lentivirus tools for over-expressing or silencing the dopamine transporter (DAT) and we evaluated the resulting behavioral profiles in terms of motivation and self-control. Wistar adult rats received stereotaxic inoculation of a lentivirus that allowed localized intra-accumbens delivery of a DAT gene enhancer/silencer, or the green fluorescent protein, GFP. These animals were studied for intolerance to delay, risk proneness and novelty seeking. As expected, controls shifted their demanding from a large reward toward a small one when the delivery of the former was increasingly delayed (or uncertain). Interestingly, in the absence of general locomotor effects, DAT over-expressing rats showed increased impulsivity (i.e. a more marked shift of demanding from the large/delayed toward the small/soon reward), and increased risk proneness (i.e. a less marked shift from the large/uncertain toward the small/sure reward), compared with controls. Rats with enhanced or silenced DAT expression did not show any significant preference for a novel environment. In summary, consistent with literature on comorbidity between attention-deficit/hyperactivity disorder and pathological gambling, we demonstrate that DAT over-expression in rats' nucleus accumbens leads to impulsive and risk prone phenotype. Thus, a reduced dopaminergic tone following altered accumbal DAT function may subserve a sensation-seeker phenotype and the vulnerability to impulse-control disorders.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Comportamento Impulsivo/genética , Comportamento Impulsivo/fisiopatologia , Núcleo Accumbens/metabolismo , Análise de Variância , Animais , Comportamento de Escolha/fisiologia , Condicionamento Operante , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Comportamento Exploratório/fisiologia , Regulação da Expressão Gênica/genética , Proteínas de Fluorescência Verde/genética , Lentivirus/metabolismo , Masculino , Mutação/genética , Probabilidade , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Wistar , Recompensa , Assunção de Riscos , Estatística como Assunto
10.
Appl Microbiol Biotechnol ; 83(3): 521-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19333594

RESUMO

Novel thermophilic and alkaliphilic bacteria for the processing of bast fibres were isolated using hemp pectin as substrate. The strain PB94A, which showed the highest growth rate (micro = 0.5/h) was identified as Geobacillus thermoglucosidasius (DSM 21625). The strain grew optimally at 60 degrees C and pH 8.5. During growth on citrus pectin, the strain produced pectinolytic lyases, which were excreted into the medium. In contrast to the commercially available pectinase Bioprep 3000 L, the enzymes from G. thermoglucosidasius PB94A converted pectin isolated from hemp fibres. In addition to hemp pectin, the culture supernatant also degraded citrus, sugar beet and apple pectin and polygalacturonic acid. When hemp fibres were incubated with the cell-free fermentation broth of G. thermoglucosidasius PB94A, the fineness of the fibres increased. The strain did not produce any cellulases, which is important in order to avoid damaging the fibres during incubation. Therefore, these bacteria or their enzymes can be used to produce fine high-quality hemp fibres.


Assuntos
Álcalis/metabolismo , Bactérias/isolamento & purificação , Bactérias/metabolismo , Cannabis/química , Pectinas/metabolismo , Bactérias/química , Bactérias/genética , Proteínas de Bactérias/metabolismo , Cannabis/metabolismo , Temperatura Alta , Dados de Sequência Molecular , Poligalacturonase/metabolismo
11.
J Chem Phys ; 130(3): 034505, 2009 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-19173529

RESUMO

Mode-selective vibrational redistribution after spectrally selective excitation within the highly structured N-H stretching band of the 7-azaindole dimer was observed by subpicosecond infrared-pump/anti-Stokes Raman-probe spectroscopy. Measurements after relaxation of the N-H stretching vibration indicate ultrafast initial population transfer to vibrations with pronounced N-H bending character. From these modes energy is transferred to modes of frequencies below 1000 cm(-1) on a slower time scale of about 3 ps. Tuning the spectrally narrow infrared excitation to the different substructures of the N-H stretching band influences the distribution of populations between the fingerprint modes. Their relative populations are correlated with the contributions of the modes forming the different coupled combination tones of the N-H stretching band. These results provide experimental support to a Fermi resonance model previously used for simulations of the N-H stretching infrared absorption band shape and insight into relaxation from the initially excited combination bands.


Assuntos
Ligação de Hidrogênio , Hidrogênio/química , Nitrogênio/química , Análise Espectral Raman/métodos , Físico-Química/métodos , DNA/química , Dimerização , Luz , Modelos Teóricos , Espalhamento de Radiação , Software , Espectrofotometria/métodos , Fatores de Tempo
12.
Biochim Biophys Acta ; 1312(3): 215-22, 1996 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-8703990

RESUMO

Plasma membrane oxidoreductases have been described in all cells and use extracellular impermeant electron acceptors (DCIP, Ferricyanide) that are reduced by NADH. They appear to regulate the overall cell activity in response to oxidative stress from the cellular environment. An NADH-DCIP reductase has been described at the plasma membrane of NB41A3, a neuroblastoma cell line (Zurbriggen and Dryer (1993) Biochim. Biophys. Acta 1183, 513-520) whose activation with extracellular impermeant substrates promotes cell growth. Elutriation was performed to separate cells and the various fractions were analysed for enzyme activity on intact cells combined with flow cytometry. These studies showed that the enzyme is mostly induced and activated during the G1 and during the G2/M-phases. These observations were further corroborated with specific inhibitors of the cell cycle. A three-fold increase in enzyme activity was observed in the presence of alpha-amanitin, a specific cell cycle inhibitor of the G1-phase. Taxol, a specific inhibitor of the M-phase, also induces a significant increase in enzyme activity. FACS analysis of taxol -treated and alpha-amanitin-treated cells corroborated these data. The cells have been synchronized and the enzyme activity was measured at different time intervals. An activity increase was observed after ca. 2-3 h, that corresponds to a raise in the M-phase, according to FACS data. Furthermore, NTera-2 cells - a human neuroblastoma cell line that differentiates into fully mature neurones in the presence of retinoic acid - exhibit a 50% decrease in the enzyme activity during the G0-phase upon differentiation, compared to undifferentiated cells. Together the data presented in this paper show that this plasma membrane NADH-diaphorase affects cell growth and differentiation and is strongly modulated at various phases of the cell cycle.


Assuntos
Ciclo Celular , Membrana Celular/enzimologia , Di-Hidrolipoamida Desidrogenase/metabolismo , Amanitinas/toxicidade , Animais , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular , Divisão Celular , Linhagem Celular , Citometria de Fluxo , Humanos , Cinética , Camundongos , Neuroblastoma , Paclitaxel/toxicidade , Fatores de Tempo , Células Tumorais Cultivadas
13.
Biochim Biophys Acta ; 1183(3): 513-20, 1994 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-8286400

RESUMO

Plasma membranes from most mammalian cells display significant transplasma membrane oxidoreductase (PMO) activity. The enzymes use an extracellular, impermeant electron acceptor as substrate and intracellular reduced pyridine nucleotide as electron donor. The plasma membrane from a neuroblastoma cell line, NB41A3, has been biotinylated and purified by immunoprecipitation with avidin and antiavidin-antibodies. The protein recovery of an immunopurified membrane preparation was < 0.15% of the protein content in the cell extract. The preparation displays an increase in the specific activity of PMO's of 15- to 20-fold compared to the activity in whole cells. With this approach the presence of a NADH-diaphorase within the cell plasma membrane can be demonstrated. This activity accounts for about one third of the total cellular diaphorase activity. The PMO activity cannot be attributed to an increased permeabilization of the plasma membrane induced upon biotinylation nor to intracellular activity from lysed cells. Activation of basal metabolism (glycolysis) stimulates PMO activity up to approx. 54%, presumably through a raise of the intracellular NADH store. PMO also promotes cell growth at low substrate concentrations (0.1-1 microM). Native gel electrophoresis of iminobiotinylated and affinity purified plasma membrane extracts displays two diaphorase-positive bands, indicating that a homogeneous cell population may express several PMO activities at the plasma membrane.


Assuntos
Di-Hidrolipoamida Desidrogenase/análise , Neuroblastoma/enzimologia , Animais , Divisão Celular , Membrana Celular/enzimologia , Di-Hidrolipoamida Desidrogenase/fisiologia , Camundongos , Oxirredução , Permeabilidade , Células Tumorais Cultivadas
14.
Biochim Biophys Acta ; 745(3): 229-36, 1983 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-6305421

RESUMO

It has been reported by Johnson et al. ((1977) Biochem. Biophys. Res. Commun. 74, 384-389) that phenacyl bromide reacts with a single reactive sulfhydryl group of aconitase, abolishing enzyme activity. Substrate or analogs have a protective effect. This group is therefore at the catalytic site of the enzyme. Aconitase is also known to be an Fe-S protein, paramagnetic as obtained on purification (Ruzicka and Beinert (1978) J. Biol. Chem. 253, 2514-2517). We have attempted to obtain information on the location of the Fe-S cluster of aconitase with respect to the catalytically active site by attaching nitroxide-labelled sulfhydryl reagents of the bromoacyl and maleimide type to the sensitive sulfhydryl group. The EPR signals of those spin-labelled sulfhydryl reagents that abolish enzyme activity disappear during reaction with aconitase. EPR spectra at 13 K of the product obtained by reaction of three spin labels (two maleimides and one bromoacyl) with aconitase included a half-field transition at g approximately equal to 4.0 which is characteristic of spin-spin interaction. On the basis of calculations of the dependence of the intensity of the half-field transition on the distance between two interacting unpaired electrons (Eaton and Eaton, (1982) J. Am. Chem. Soc. 104, 5002-5003) the distances between the nitroxide N-O bond and the center of the Fe-S cluster for the three spin labels were calculated to be 10.5, 11 and 13 A. Combined distance and orientation data for the three spin labels indicate that the reactive sulfhydryl group is about 12 A from the center of the Fe-S cluster.


Assuntos
Aconitato Hidratase/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Metaloproteínas/metabolismo , Marcadores de Spin/farmacologia , Animais , Sítios de Ligação , Bovinos , Espectroscopia de Ressonância de Spin Eletrônica , Cinética , Miocárdio/enzimologia , Conformação Proteica , Marcadores de Spin/síntese química , Relação Estrutura-Atividade
15.
Mar Environ Res ; 59(4): 367-80, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15589987

RESUMO

When Hurricane Iniki struck the Hawaiian Islands in September 1992, it provided a rare opportunity to examine the immediate effects of a hurricane on two intertidal benthic communities off the reefs of O'ahu, Hawai'i. The Niu Beach site contained large, obvious aggregations of the tube building polychaete Diopatra dexiognatha, and the Wailupe Beach site was without obvious tubiculous fauna at the surface. Ten replicate sediment cores were taken before and after the hurricane with a 7.6 cm PVC corer and organisms were identified to family and enumerated. There were no substantial depletions or loss of taxa after the hurricane. Oligochaetes were the most dominant taxa pre-and post-hurricane. The abundance of all dominant polychaete families increased post-hurricane. The three most abundant polychaetes were capitellids and D. dexiognatha (Onuphidae) at Niu Beach and Pygospio muscularis (Spionidae) at Wailupe Beach. We suggest that D. dexiognatha and P. muscularis help stabilize the sediments since they both form dense tube mats while capitellids and oligochaetes are considered highly adaptive surface burrowers that can take advantage of newly disturbed sediments. Overall, there was no substantial effect observed on the intertidal fauna exposed to this severe disturbance. It is suggested here that invertebrate communities in this area are adapted to survive and thrive in high-energy environments and possibly benefit from dense aggregations of tube building polychaetes.


Assuntos
Desastres , Poliquetos/crescimento & desenvolvimento , Animais , Classificação , Ecossistema , Sedimentos Geológicos , Havaí , Dinâmica Populacional
16.
Medicine (Baltimore) ; 60(3): 139-72, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7231152

RESUMO

Clinical and laboratory features of 31 patients with coccidioidal meningitis seen from January 1964 through December 1976 with follow-up through 1979 are reported and data on 114 patients from the literature reviewed. History of exposure to C. immitis, a wide age range, and, in about one third, underlying conditions are noteworthy. Dissemination to the meninges usually occurs within the first few months although diagnosis is frequently delayed. Presenting symptoms and signs of coccidioidal meningitis are varied but signs of chronic meningitis or suggestion of hydrocephalus are prominent. Evidence of acute infection is unusual even with widespread disease. Diagnosis is usually made by demonstration of coccidioidal CF antibodies in the CSF although they are not found in all patients. Some show other direct evidence of C. immitis. Special diagnostic techniques such as CAT scanning for evidence of basilar meningitis or hydrocephalus are valuable. Amphotericin B remains the drug of choice despite the need for long-term therapy and the problems with intrathecal administration. Reservoirs are only occasionally useful but shunts are frequently lifesaving despite complications. Factors associated with a bad prognosis are hydrocephalus, non-Caucasian race, or presence of an underlying disease.


Assuntos
Coccidioidomicose/diagnóstico , Meningite/diagnóstico , Adolescente , Adulto , Coccidioidomicose/terapia , Feminino , Humanos , Masculino , Meningite/etiologia , Meningite/terapia , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Brain Res Mol Brain Res ; 90(1): 68-74, 2001 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-11376857

RESUMO

CD81, also known as target of the antiproliferative antibody, is known to be expressed in astrocytes and involved in cell adhesion and, recently, we demonstrated its induction exclusively in the accumbens following cocaine. In the present study, the sensitivity of CD81-deficient mice to behavioral effects of cocaine was evaluated. It was found that CD81-deficient mice exhibited altered sensitivity to cocaine as assessed in the place preference conditioning paradigm and locomotor activity. This deficit in place preference conditioning was not accompanied by a deficit in acquisition or retention of water maze behavior. In addition, CD81 knockout mice exhibited higher levels of nucleus accumbens dopamine as compared to their controls. These observations are discussed in the context of the role of CD81 in cocaine-mediated behaviors.


Assuntos
Antígenos CD/fisiologia , Cocaína/toxicidade , Aprendizagem em Labirinto/efeitos dos fármacos , Proteínas de Membrana , Atividade Motora/efeitos dos fármacos , Proteínas do Tecido Nervoso/fisiologia , Comportamento Espacial/efeitos dos fármacos , Animais , Antígenos CD/genética , Corpo Estriado/metabolismo , Dopamina/metabolismo , Resistência a Medicamentos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Neurotransmissores/metabolismo , Núcleo Accumbens/metabolismo , Tetraspanina 28
18.
Urology ; 21(1): 37-41, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6186064

RESUMO

The effect of prostatic massage on the concentration of prostatic acid phosphatase (PAP) in blood serum as determined by radioimmunoassay (RIA) was compared with that determined by a standard enzymatic assay (EA). Serum was drawn from 24 men before prostatic massage and after--at specified intervals, up to twenty-four hours. Three of these men were young, normal controls; 10 had biopsy-proved prostate cancer (CA); 11 had histologically confirmed benign prostatic hyperplasia (BPH). After prostatic massage, 3 of the 10 CA patients (30%) had elevation of PAP as determined by EA and 4 of the 11 BPH patients (36%) as determined by RIA. None of the controls showed elevated levels of PAP by either assay. In all patients elevated levels of PAP by both assays had returned to normal twenty-four hours after massage. It was concluded that serum for PAP testing by either assay method should be drawn before or twenty-four hours after rectal examination to prevent false positive results and the need for retesting.


Assuntos
Fosfatase Ácida/sangue , Massagem , Próstata , Adulto , Biópsia , Ensaios Enzimáticos Clínicos , Reações Falso-Positivas , Humanos , Masculino , Exame Físico , Próstata/enzimologia , Hiperplasia Prostática/enzimologia , Hiperplasia Prostática/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Radioimunoensaio , Fatores de Tempo
19.
Brain Res Dev Brain Res ; 89(2): 235-52, 1995 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-8612327

RESUMO

Transplasma membrane redox plays a significant role in cellular activation and growth. Six isoenzymes could be prepared from purified rat brain synaptic plasma membrane. Polyclonal antibodies have been prepared against six transplasma membrane oxydoreductases (PMO-I to PMO-VI) and the tissue distribution of the various iso-enzymes have been investigated in adult rat brains by means of immunohistochemistry. PMO-I is densely observed in layers I, IV and V of the parietal cortex, in CA1 of the hippocampus (except for the molecular layer), in the caudate putamen, in the dorsal, granular and ventral parts of the auditory nuclei, in some loci of the vestibular nuclei as well as in the deep cerebellar nucleus and in the granular layer of the cerebellar cortex. PMO-II is mainly located in the polymorphic layer of the dentate gyrus and in the deep cerebellar nucleus and in the granular layer of the cerebellar cortex. PMO-III is abundant in the piriform cortex, in the pyramidal layers of both CA1 and CA2, in the diagonal band of the basal ganglia, in the supraoptic nucleus and in various loci of the magnetocellular paraventricular nucleus of the hippothalamus as well as in the vestibular nuclei from the brain stem. In addition PMO-III is also densely present in motor nuclei (oculomotor, facial, hypoglossal and ambiguus nuclei), in the reticular formation and in the deep cerebellar nucleus as well as in the Purkinje layer of the cerebellar cortex. PMO-IV has a similar location but is less abundant in the vestibular nuclei of the sensory brain stem and in the motor nucleus. PMO-V in contrast is poorly present in most brain areas compared to the other iso-enzymes, apart of the Purkinje layer of the cerebellar cortex. Finally PMO-VI is mainly present in the oriens layer and in the stratum radiatum of the hippocampus formation, in the supraoptic and lateral magnocellular nucleus of the hypothalamus, in the mesencephalic trigeminal nucleus, in the ventral auditory nucleus and in the facial nucleus of the brain stem as well as in red nucleus of the reticular formation and in the Purkinje layer of the cerebellar cortex. These data show that the iso-enzymes are located in specific brain nuclei. The significance of the results in respect to the yet very poorly defined function of PMO's is discussed.


Assuntos
Encéfalo/enzimologia , Isoenzimas/análise , NADH Desidrogenase/análise , Animais , Encéfalo/ultraestrutura , Tronco Encefálico/enzimologia , Membrana Celular/enzimologia , Feminino , Imuno-Histoquímica , Masculino , Prosencéfalo/enzimologia , Ratos , Ratos Sprague-Dawley
20.
Brain Res Dev Brain Res ; 89(2): 253-63, 1995 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-8612328

RESUMO

The function of transplasma membrane oxidoreductases (PMO's) has been further studied by means of investigating the postnatal (PN) developmental changes in the tissue localization of six isoenzymes previously characterized (see accompanying paper). The changes were followed in the midbrain for PMO-I, -II, and -V and in the brainstem for PMO-III, -IV and -VI. PMO-I is not observed before PN5 and develops as long vertical fibers located mainly in the pontine nucleus and in the dorsal raphe nucleus until it merges all over the midbrain except for the aqueduct and the superior colliculus after PN10. At that stage it is highly expressed in the trigeminal nucleus and the dorsal raphe, but its expression then strongly decreases and PMO-I disappears almost completely later on. Similarly PMO-II only develops around PN5, first in the dorsal and caudal linear raphe and later on (at PN7) also in the pontine nucleus and in the median raphe; at PN10 PMO-II gradually had vanished from these areas and strongly developed in the dorsal raphe and in the mesencephalic trigeminal nucleus. Later on PMO-II also decreases from these areas. PMO-III slowly develops within the gigantocellular reticular nucleus from PN1 to PN5 and later on reaches the facial nucleus (after PN5), the density of PMO-III in these regions at PN10 being much higher than in the adult. PMO-IV follows a similar developmental pattern in the midbrain, with an optimal density around PN10 also. PMO-V appears only at about PN5, first within the dorsal raphe in parallel fibers and in multipolar neurons. It disappears from the fibers around PN10 and remains present in neurons up to adulthood. PMO-VI appears at early stages within the gigantocellular reticular nucleus and after PN5 within the central gray in vertical fibers. At later stages PMO-VI is found in the spinal trigeminal nucleus, at first within the neuropil then in multipolar neurons that remain present up to adulthood. These datas suggested that the different isoenzymes are expressed at various stages in specific areas. The role of PMO's in neuronal development is discussed.


Assuntos
Encéfalo/enzimologia , Isoenzimas/análise , NADH Desidrogenase/análise , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/ultraestrutura , Tronco Encefálico/enzimologia , Membrana Celular/enzimologia , Técnicas Imunoenzimáticas , Mesencéfalo/enzimologia , Ratos , Ratos Sprague-Dawley
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