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1.
Am Heart J ; 214: 107-112, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31200280

RESUMO

Critical limb ischemia is associated with excessively high risk for cardiovascular events, including myocardial infarction and death. Additionally, in this patient population non-invasive evaluation of coronary artery disease is limited due to (1) inability of exercise testing, (2) frequent occurrence of balanced ischemia and (3) frequent occurrence of diffuse coronary calcification. Intentional Coronary Revascularization Versus Conservative Therapy in Patients Undergoing Peripheral Artery Revascularization Due to Critical Limb Ischemia trial (INCORPORATE trial) is a multicentric international randomized open label clinical trial. Trial will recruit patients, who underwent successful peripheral artery revascularization due to critical limb ischemia and randomize 1:1 to conservative medical therapy versus an immediate invasive strategy to investigate and treat coronary artery disease. The objective is to evaluate whether intentional invasive strategy with ischemia targeted reasonably complete coronary revascularization is superior as compared to conventional primarily conservative approach in terms of spontaneous myocardial infarction and overall survival at 12 months follow-up. The trial is registered at clinicaltrials.gov (NCT03712644).


Assuntos
Tratamento Conservador , Doença da Artéria Coronariana/terapia , Isquemia/complicações , Perna (Membro)/irrigação sanguínea , Intervenção Coronária Percutânea , Ensaios Clínicos Controlados Aleatórios como Assunto , Cateterismo Periférico , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , Diagnóstico Precoce , Reserva Fracionada de Fluxo Miocárdico , Humanos , Isquemia/terapia , Estudos Multicêntricos como Assunto , Doença Arterial Periférica/complicações
2.
Phys Rev Lett ; 115(20): 200403, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26613423

RESUMO

We show how a test of macroscopic realism based on Leggett-Garg inequalities (LGIs) can be performed in a macroscopic system. Using a continuous-variable approach, we consider quantum nondemolition (QND) measurements applied to atomic ensembles undergoing magnetically driven coherent oscillation. We identify measurement schemes requiring only Gaussian states as inputs and giving a significant LGI violation with realistic experimental parameters and imperfections. The predicted violation is shown to be due to true quantum effects rather than to a classical invasivity of the measurement. Using QND measurements to tighten the "clumsiness loophole" forces the stubborn macrorealist to recreate quantum backaction in his or her account of measurement.

3.
Catheter Cardiovasc Interv ; 85(7): 1173-81, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25381869

RESUMO

OBJECTIVES: To compare the effective radiation dose (ERD) needed to obtain information on coronary anatomy and physiology by a non-invasive versus an invasive diagnostic strategy. BACKGROUND: Knowledge of anatomy and physiology is needed for management of patients with coronary artery disease (CAD). There is, however, a growing concern about detrimental long-term effects of radiation associated with diagnostic procedures. METHODS: In a total of 671 patients with suspected CAD, we compared the ERD needed to obtain anatomical and physiological information through a non-invasive strategy or an invasive strategy. The non-invasive strategy consisted of coronary computed tomography angiography (CCTA) and single photon emission computed tomography (SPECT). The invasive strategy included coronary angiography (CA) and fractional flow reserve (FFR) measurement. In 464 patients, the data were acquired in Period 2009 and in 207 the data were acquired in Period 2011 (after each period, the CCTA- and the CA-equipment had been upgraded). RESULTS: For the Period 2009 total ERD of the non-invasive approach was significantly larger compared to the invasive approach (28.45 ± 5.37 mSv versus 15.79 ± 7.95 mSv, respectively; P < 0.0001). For Period 2011, despite the significant decrease in ERD for both groups (P<0.0001 for both), the ERD remained higher for the non-invasive approach compared to the invasive approach (16.67 ± 10.45 mSv vs. 10.36 ± 5.87 mSv, respectively; P < 0.0001). Simulation of various diagnostic scenarios showed cumulative radiation dose is the lowest when a first positive test is followed by an invasive strategy. CONCLUSION: To obtain anatomic and physiologic information in patients with suspected CAD, the combination of CA and FFR is associated with lower ERD than the combination of CCTA and SPECT.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Imagem de Perfusão do Miocárdio/métodos , Doses de Radiação , Tomografia Computadorizada por Raios X , Idoso , Cateterismo Cardíaco , Angiografia Coronária/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Imagem de Perfusão do Miocárdio/efeitos adversos , Valor Preditivo dos Testes , Prognóstico , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X/efeitos adversos
4.
Nature ; 462(7276): 1036-8, 2009 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-20033043

RESUMO

Magnetic fields play an important (sometimes dominant) role in the evolution of gas clouds in the Galaxy, but the strength and orientation of the field in the interstellar medium near the heliosphere has been poorly constrained. Previous estimates of the field strength range from 1.8-2.5 microG and the field was thought to be parallel to the Galactic plane or inclined by 38-60 degrees (ref. 2) or 60-90 degrees (ref. 3) to this plane. These estimates relied either on indirect observational inferences or modelling in which the interstellar neutral hydrogen was not taken into account. Here we report measurements of the deflection of the solar wind plasma flows in the heliosheath to determine the magnetic field strength and orientation in the interstellar medium. We find that the field strength in the local interstellar medium is 3.7-5.5 microG. The field is tilted approximately 20-30 degrees from the interstellar medium flow direction (resulting from the peculiar motion of the Sun in the Galaxy) and is at an angle of about 30 degrees from the Galactic plane. We conclude that the interstellar medium field is turbulent or has a distortion in the solar vicinity.

5.
Eur J Soil Sci ; 66(1): 226-238, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25866465

RESUMO

A range of continental-scale soil datasets exists in Europe with different spatial representation and based on different principles. We developed comprehensive pedotransfer functions (PTFs) for applications principally on spatial datasets with continental coverage. The PTF development included the prediction of soil water retention at various matric potentials and prediction of parameters to characterize soil moisture retention and the hydraulic conductivity curve (MRC and HCC) of European soils. We developed PTFs with a hierarchical approach, determined by the input requirements. The PTFs were derived by using three statistical methods: (i) linear regression where there were quantitative input variables, (ii) a regression tree for qualitative, quantitative and mixed types of information and (iii) mean statistics of developer-defined soil groups (class PTF) when only qualitative input parameters were available. Data of the recently established European Hydropedological Data Inventory (EU-HYDI), which holds the most comprehensive geographical and thematic coverage of hydro-pedological data in Europe, were used to train and test the PTFs. The applied modelling techniques and the EU-HYDI allowed the development of hydraulic PTFs that are more reliable and applicable for a greater variety of input parameters than those previously available for Europe. Therefore the new set of PTFs offers tailored advanced tools for a wide range of applications in the continent.

6.
Klin Monbl Augenheilkd ; 231(9): 921-3, 2014 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-25181507

RESUMO

BACKGROUND: Four eyes of two patients were injured simultaneously by industrial alkali while working. One eye of both patients healed without later consequences. PATIENTS AND METHODS: Two eyes were treated with phototherapeutic keratectomy (PTK) because of recurrent corneal erosion syndrome caused by alkali burn. RESULTS: In both cases reepithelisation of the cornea was completed by the end of the 1st postoperative week, the injured persons were able to work again. No recurrence was experienced in the next 6 months of follow-up. CONCLUSION: With these cases the authors would like to draw attention to the possible complications, as well as the importance of careful balancing and adequate management.


Assuntos
Álcalis/intoxicação , Doenças da Córnea/induzido quimicamente , Doenças da Córnea/terapia , Distrofias Hereditárias da Córnea/induzido quimicamente , Distrofias Hereditárias da Córnea/terapia , Epitélio Corneano/patologia , Queimaduras Oculares/induzido quimicamente , Queimaduras Oculares/terapia , Doenças da Córnea/diagnóstico , Distrofias Hereditárias da Córnea/diagnóstico , Queimaduras Oculares/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Ceratectomia Fotorrefrativa/métodos , Recidiva , Resultado do Tratamento
7.
J Anim Breed Genet ; 130(4): 312-20, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23855633

RESUMO

The genetic relationship between 195 Mangalica and 79 non-Mangalica pigs was studied using mitochondrial D-loop SNP genotyping. Altogether, 35 polymorphic sites and 27 haplotypes were identified. Of the haplotypes, eight and 16 are Mangalica and non-Mangalica specific, respectively, while three contain both Mangalica and non-Mangalica individuals. Genetic distance values and phylogenetic analysis indicate that Mangalica individuals are very closely related, and five haplotypes represent approximately 92% of the Mangalica pigs involved in the study, thus determining the major maternal lineages. In contrast to previous microsatellite studies, individuals of Mangalica could not be distinguished as three separate breeds using mtDNA genotyping. Comparing modern and archaeological mtDNA sequences revealed that present day Mangalica is related to pigs that lived in the Carpathian basin where postulated ancestors of Mangalica also lived. This is the first DNA-based genetic evidence to support the described breeding history of Mangalica.


Assuntos
DNA Mitocondrial/química , DNA Mitocondrial/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Sus scrofa/genética , Animais , Evolução Molecular , Feminino , Técnicas de Genotipagem
8.
Phys Rev Lett ; 106(4): 045701, 2011 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21405334

RESUMO

We address crystal nucleation and fcc-bcc phase selection in alloys using a multiphase field model that relies on Ginzburg-Landau free energies of the liquid-fcc, liquid-bcc, and fcc-bcc subsystems, and determine the properties of the nuclei as a function of composition, temperature, and structure. With a realistic choice for the free energy of the fcc-bcc interface, the model predicts well the fcc-bcc phase-selection boundary in the Fe-Ni system.

9.
SAR QSAR Environ Res ; 32(4): 247-268, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33749419

RESUMO

The dependence of statistical validation parameters was investigated on the size of the sample taken in fit of multivariate linear curves. We observed that R2 and related internal parameters were misleading as they overestimated the goodness-of-fit of models at small sample size. Cross-validation metrics showed correct trends. It was possible to scale the leave-one-out and the leave-many-out results close to identical by correcting the degrees of freedom of the models. y and x-randomized validation parameters were calculated and the methods provided close to identical results. We suggest to use the simplest methods in both cases. The external parameters followed correct trends with respect to the sample size, but their sensitivity differed. We plotted the Roy-Ojha metrics in 2D and we coloured them with respect to other external parameters to provide an easy classification of models. The rank correlations were calculated between the performance parameters. Up to a sample size, goodness-of-fit and robustness were distinguishable, but above a certain sample size, the parameters were redundant. The external-internal pairs were weakly correlated. Our data show that all the three aspects of validation are necessary at small sample sizes, but the internal check of robustness is not informative above a given sample size.


Assuntos
Modelos Lineares , Relação Quantitativa Estrutura-Atividade , Tamanho da Amostra
10.
Phys Rev Lett ; 105(25): 250403, 2010 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-21231565

RESUMO

We present a scalable method for the tomography of large multiqubit quantum registers. It acquires information about the permutationally invariant part of the density operator, which is a good approximation to the true state in many relevant cases. Our method gives the best measurement strategy to minimize the experimental effort as well as the uncertainties of the reconstructed density matrix. We apply our method to the experimental tomography of a photonic four-qubit symmetric Dicke state.

11.
Biochim Biophys Acta Biomembr ; 1862(8): 183246, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32142818

RESUMO

The filamentous fungus Penicillium chrysogenum Q176 secretes the antimicrobial proteins (AMPs) PAF and PAFB, which share a compact disulfide-bond mediated, ß-fold structure rendering them highly stable. These two AMPs effectively inhibit the growth of human pathogenic fungi in micromolar concentrations and exhibit antiviral potential without causing cytotoxic effects on mammalian cells in vitro and in vivo. The antifungal mechanism of action of both AMPs is closely linked to - but not solely dependent on - the lipid composition of the fungal cell membrane and requires a strictly regulated protein uptake into the cell, indicating that PAF and PAFB are not canonical membrane active proteins. Variations in their antifungal spectrum and their killing dynamics point towards a divergent mode of action related to their physicochemical properties and surface charge distribution. In this review, we relate characteristic features of PAF and PAFB to the current knowledge about other AMPs of different sources. In addition, we present original data that have never been published before to substantiate our assumptions and provide evidences that help to explain and understand better the mechanistic function of PAF and PAFB. Finally, we underline the promising potential of PAF and PAFB as future antifungal therapeutics.


Assuntos
Antifúngicos/química , Peptídeos Catiônicos Antimicrobianos/química , Proteínas Fúngicas/química , Micoses/tratamento farmacológico , Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/farmacologia , Apoptose/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Cisteína/genética , Proteínas Fúngicas/genética , Humanos , Lipídeos de Membrana/química , Micoses/genética , Micoses/microbiologia , Penicillium chrysogenum/química , Penicillium chrysogenum/genética
12.
Neuroscience ; 158(2): 867-74, 2009 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-18977279

RESUMO

Leu- and Met-enkephalin were the first endogenous opioid peptides identified in different mammalian species including the human. Comparative biochemical and bioinformatic evidence indicates that enkephalins are not limited to mammals. Various prodynorphin (PDYN) sequences in lower vertebrates revealed the presence of other enkephalin fingerprints in these precursor polypeptides. Among the novel enkephalins Ile-enkephalin (Tyr-Gly-Gly-Phe-Ile) was primarily observed in the African clawed frog (Xenopus laevis) PDYNs, while the structure of Phe-enkephalin (Tyr-Gly-Gly-Phe-Phe) was predicted by analyzing brain cDNA sequences encoding a PDYN of the African lungfish (Protopterus annectens). Ile-enkephalin can also be found in the PDYNs of four other fish species including the eel, bichir, zebrafish and tilapia, but no further occurrence for the Phe-enkephalin motif is available as yet. Based on sequencing data, the biological relevance of Phe- and Ile-enkephalin is suggested, because both of them can arise by regular posttranslational enzymatic processing of the respective neuropeptide precursors. In various receptor binding assays performed on rat brain membrane preparations both of the new peptides turned out to be moderate affinity opioids with a weak preference for the delta-opioid receptor (DOP) sites. Phe-enkephalin of the lungfish displayed rather unexpectedly low affinities toward the mu-opioid receptor (MOP) and DOP, while exhibiting moderate affinity toward the kappa-opioid receptor (KOP). In receptor-mediated G-protein activation assays measured by the stimulation of [(35)S]GTPgammaS binding, Met-enkephalin produced the highest stimulation followed by Leu-enkephalin, Ile-enkephalin and Phe-enkephalin, whereas the least efficacious among these endogenous peptides was still more effective than the prototype opiate agonist morphine in these functional tests.


Assuntos
Anuros/genética , Encéfalo/metabolismo , Encefalinas/genética , Encefalinas/metabolismo , Peixes/genética , Analgésicos Opioides/farmacologia , Animais , Sequência de Bases , DNA Complementar/genética , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Encefalinas/química , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Peptídeos Opioides/farmacologia , Ligação Proteica/efeitos dos fármacos , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Ratos , Ratos Wistar , Receptores Opioides delta/metabolismo , Receptores Opioides mu/metabolismo , Trítio/farmacologia
13.
Br J Dermatol ; 161(5): 1105-11, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19673878

RESUMO

BACKGROUND: Punch grafting is a simple and frequently used technique for the treatment of stable vitiligo, resistant to medical therapy. However, studies reporting long-term results are exceptional. OBJECTIVES: To evaluate the long-term results of 2-mm punch grafting in patients with vitiligo vulgaris and segmental vitiligo. METHODS: We studied a prospective cohort study involving 61 patients (25 male, 36 female) with vitiligo vulgaris and nine patients (all male) with segmental vitiligo who underwent 2-mm punch grafting more than 3 years ago. The main outcome measure was the degree of repigmentation of a single transplanted lesion as measured with a digital image analysis system with a mean follow-up of 5.2 years. RESULTS: In patients with vitiligo vulgaris, 17 lesions (28%) showed excellent, 14 lesions (23%) showed good, 14 lesions (23%) showed fair and 16 lesions (26%) showed poor repigmentation. In patients with segmental vitiligo, seven of nine lesions (78%) showed excellent repigmentation. A cobblestone-like effect was observed in 19 of 70 patients (27%). Disease activity after punch grafting was reported in 94% of patients with poor repigmentation but in only 18% of patients with excellent repigmentation (chi(2) test, P < 0.0005). Patients who reported disease activity after transplantation had a lower mean repigmentation than those who did not report disease activity (77% vs. 39%, P < 0.05). CONCLUSIONS: Two-millimetre punch grafting in vitiligo is an effective surgical procedure with long-lasting effect. To prevent a cobblestone-like effect, we advise the use of smaller grafts (1-1.2 mm). Disease activity after grafting, localization and type of vitiligo, prior ultraviolet B treatment and a Koebnerized donor site influence the long-term outcome of punch grafting and should be taken into account in the selection of patients eligible for this treatment.


Assuntos
Pigmentação da Pele , Transplante de Pele/métodos , Vitiligo/cirurgia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Análise Espectral , Transplante Autólogo , Resultado do Tratamento , Vitiligo/patologia , Adulto Jovem
14.
Neuroscience ; 155(2): 387-402, 2008 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-18590802

RESUMO

The aim of this study was to show the presence, distribution and function of the pituitary adenylate cyclase activating polypeptide (PACAP) and its receptors in the CNS and peripheral nervous system of the mollusk, Helix pomatia. PACAP-like and pituitary adenylate cyclase activating polypeptide receptor (PAC1-R)-like immunoreactivity was abundant both in the CNS and the peripheral nervous system of the snail. In addition several non-neuronal cells also revealed PACAP-like immunoreactivity. In inactive animals labeled cell bodies were mainly found and in the neuropile of active animals dense immunostained fiber system was additionally detected suggesting that expression of PACAP-like peptide was affected by the behavioral state of the animal. RIA measurements revealed the existence of both forms of PACAP in the CNS where the 27 amino acid form was found to be dominant. The concentration of PACAP27 was significantly higher in samples from active animals supporting the data obtained by immunohistochemistry. In Western blot experiments PACAP27 and PACAP38 antibodies specifically labeled protein band at 4.5 kDa both in rat and snail brain homogenates, and additionally an approximately 14 kDa band in snail. The 4.5 kDa protein corresponds to PACAP38 and the 14 kDa protein corresponds to the preproPACAP or to a PACAP-like peptide having larger molecular weight than mammalian PACAP38. In matrix-assisted laser desorption ionization time of flight (MALDI TOF) measurements fragments of PACAP38 were identified in brain samples suggesting the presence of a large molecular weight peptide in the snail. Applying antibodies developed against the PACAP receptor PAC1-R, immunopositive stained neurons and a dense network of fibers were identified in each of the ganglia. In electrophysiological experiments, extracellular application of PACAP27 and PACAP38 transiently depolarized or increased postsynaptic activity of neurons expressing PAC1-R. In several neurons PACAP elicited a long lasting hyperpolarization which was eliminated after 1.5 h continuous washing. Taken together, these results indicate that PACAP may have significant role in a wide range of basic physiological functions in snail.


Assuntos
Comportamento Alimentar/fisiologia , Caracois Helix/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Adenilil Ciclases/metabolismo , Sequência de Aminoácidos , Estruturas Animais/metabolismo , Animais , Química Encefálica , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/metabolismo , Hemolinfa/metabolismo , Imuno-Histoquímica , Dados de Sequência Molecular , Sistema Nervoso/química , Sistema Nervoso/citologia , Sistema Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/análise , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Radioimunoensaio , Ratos , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Br J Pharmacol ; 154(4): 872-81, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18536739

RESUMO

BACKGROUND AND PURPOSE: Insulin-regulated aminopeptidase (IRAP) and the insulin-dependent glucose transporter GLUT4 colocalize in specific intracellular vesicles (that is, GLUT4 vesicles). These vesicles move slowly to the cell surface, but their translocation is markedly enhanced by insulin, resulting in higher glucose uptake. Previous studies of the insulin-mediated translocation of IRAP to the cell surface have been hampered by the laborious detection of IRAP at the cell surface. We aimed to develop a more direct and faster method to detect IRAP. To this end, we used model systems with well-characterized IRAP: CHO-K1 cells expressing endogenous IRAP and recombinant HEK293 cells expressing human IRAP. A more widespread application of the method was demonstrated by the use of 3T3-L1 adipocytes. EXPERIMENTAL APPROACH: After stimulation of the cells with insulin, internalization of IRAP was inhibited by the addition of phenyl arsine oxide (PAO). Then, cell-surface IRAP was detected by the high-affinity binding of radiolabelled angiotensin (Ang) IV (either 125I or 3H). KEY RESULTS: We monitored the time- and concentration dependence of insulin-mediated translocation of IRAP in both cell lines and 3T3-L1 adipocytes. A plateau was reached between 6 and 8 min, and 10(-7) M insulin led to the highest amount of IRAP at the cell surface. CONCLUSIONS AND IMPLICATIONS: Based on the capacity of the IRAP apoenzyme to display high affinity for radiolabelled Ang IV and on the ability of PAO to inhibit IRAP internalization, we developed a more direct and faster method to measure insulin-mediated translocation of IRAP to the cell surface.


Assuntos
Cistinil Aminopeptidase/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Insulina/farmacologia , Ensaio Radioligante/métodos , Células 3T3 , Adipócitos/metabolismo , Animais , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Humanos , Insulina/administração & dosagem , Camundongos , Transporte Proteico , Fatores de Tempo
16.
J Mol Neurosci ; 36(1-3): 270-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18607779

RESUMO

The effects of pituitary adenylate cyclase activating polypeptide (PACAP) are mediated through G-protein-coupled receptors, the specific PAC1 receptor and VPAC1 and VPAC2 receptors which bind vasoactive intestinal peptide with similar affinity. Based on binding affinity studies, PACAP6-38 was discovered as a potent antagonist of PAC1 and it has been used by hundreds of studies as a PACAP antagonist. Recently, we have found that in certain cells/tissues, PACAP6-38 does not antagonize PACAP-induced effects, but surprisingly, it exerts similar actions to PACAP1-38, behaving as an agonist. In the present study, we report on the agonistic behavior of PACAP6-38 on neuropeptide release from sensory nerves of the isolated rat trachea and on the MAPK signaling pathways in cytotrophoblast cells. In isolated rat tracheae, PACAP6-38, similarly to PACAP1-38, induced significant inhibitory effects on the release of three simultaneously measured sensory neuropeptides, substance P, calcitonin gene-related peptide, and somatostatin evoked by both chemical excitation and electrical field stimulation of capsaicin-sensitive afferents. Effects of PACAP6-38 were the same as those of PACAP1-38 on MAPK signaling in human cytotrophoblast cells. Western blot analysis showed that both peptide forms stimulated ERK1/2 and JNK phosphorylation, while they both inhibited p38 MAPK phosphorylation. The most pronounced effects were observed when both peptides were present. In summary, our results show that PACAP6-38, which is a PACAP receptor antagonist in most cells/tissues, can behave as an agonist in other systems. The increasing interest in the effects of PACAP requires further studies on the pharmacological properties of the peptide and its analogues.


Assuntos
Fragmentos de Peptídeos/farmacologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Células Receptoras Sensoriais/efeitos dos fármacos , Trofoblastos , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Capsaicina/farmacologia , Linhagem Celular Tumoral , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ratos , Ratos Wistar , Células Receptoras Sensoriais/metabolismo , Fármacos do Sistema Sensorial/farmacologia , Somatostatina/metabolismo , Substância P/metabolismo , Técnicas de Cultura de Tecidos , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Trofoblastos/citologia , Trofoblastos/efeitos dos fármacos
17.
Regul Pept ; 145(1-3): 105-15, 2008 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-17981349

RESUMO

The neuropeptide PACAP (pituitary adenylate cyclase activating polypeptide) and its receptors are widely expressed in the nervous system and various other tissues. PACAP has well-known anti-apoptotic effects in neuronal cell lines. Recent data suggest that PACAP exerts anti-apoptotic effects also in non-neuronal cells. The peptide is present in the cardiovascular system, and has various distinct effects. The aim of the present study was to investigate whether PACAP is protective against in vitro ischemia/reperfusion-induced apoptosis in cardiomyocytes. Cultured cardiomyocytes were exposed to 60 min ischemia followed by 120 min reperfusion. The addition of PACAP1-38 significantly increased cell viability and decreased the ratio of apoptotic cells as measured by MTT test and flow cytometry. PACAP induced the phosphorylation of Akt and protein kinase A. In the present study we also examined the possible involvement of Akt- and protein kinase A-induced phosphorylation and thus inactivation of Bad, a pro-apoptotic member of the Bcl-2 family. It was found that ischemia significantly decreased the levels of phosphorylated Bad, which was counteracted by PACAP. Furthermore, PACAP increased the levels of Bcl-xL and 14-3-3 protein, both of which promote cell survival, and decreased the apoptosis executor caspase-3 cleavage. All effects of PACAP1-38 were inhibited by the PACAP antagonist PACAP6-38. In summary, our results show that PACAP has protective effects against ischemia/reperfusion-induced cardiomyocyte apoptosis and provides new insights into the signaling mechanisms involved in the PACAP-mediated anti-apoptotic effects.


Assuntos
Proteínas 14-3-3/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Citoproteção/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
19.
J Geophys Res Space Phys ; 123(4): 2851-2871, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33510994

RESUMO

We present a new expansion of the Polar Wind Outflow Model (PWOM) to include kinetic ions using the Particle-in-Cell (PIC) approach with Monte Carlo collisions. This implementation uses the original hydrodynamic solution at low altitudes for efficiency, and couples to the kinetic solution at higher altitudes to account for kinetic effects important for ionospheric outflow. The modeling approach also includes wave-particle interactions, suprathermal electrons, and an hybrid parallel computing approach combining shared and distributed memory paralellization. The resulting model is thus a comprehensive, global, model of ionospheric outflow that can be run efficiently on large supercomputing clusters. We demonstrate the model's capability to study a range of problems starting with the comparison of kinetic and hydrodynamic solutions along a single field line in the sunlit polar cap, and progressing to the altitude evolution of the ion conic distribution in the cusp region. The interplay between convection and the cusp on the global outflow solution is also examined. Finally, we demonstrate the impact of these new model features on the magnetosphere by presenting the first 2-way coupled ionospheric outflow-magnetosphere calculation including kinetic ion effects.

20.
Physiol Res ; 67(5): 777-785, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-28787171

RESUMO

The glycosaminoglycan (GAG) molecules are a group of high molecular weight, negatively charged polysaccharides present abundantly in the mammalian organism. By their virtue of ion and water binding capacity, they may affect the redistribution of body fluids and ultimately the blood pressure. Data from the literature suggests that the mitogens Vascular Endothelial Growth Factor (VEGF)-A and VEGF-C are able to regulate the amount and charge density of GAGs and their detachment from the cell surface. Based on these findings we investigated the relationship between the level of dietary sodium intake, the expression levels of VEGF-A and VEGF-C, and the amount of the skin GAGs hyaluronic acid and chondroitin sulfate in an in vivo rat model. Significant correlation between dietary sodium intake, skin sodium levels and GAG content was found. We confirmed the GAG synthesizing role of VEGF-C but failed to prove that GAGs are degraded by VEGF-A. No significant difference in blood pressure was registered between the different dietary groups. A quotient calculated form the ion and water content of the skin tissue samples suggests that - in contrast to previous findings - the osmotically inactive ions and bound water fractions are proportional.


Assuntos
Glicosaminoglicanos/metabolismo , Pele/metabolismo , Sódio na Dieta/administração & dosagem , Sódio/fisiologia , Animais , Feminino , Distribuição Aleatória , Ratos , Ratos Wistar , Pele/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/biossíntese
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