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1.
Purinergic Signal ; 20(2): 115-125, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37246192

RESUMO

During the establishment of neuronal circuits, axons and dendrites grow and branch to establish specific synaptic connections. This complex process is highly regulated by positive and negative extracellular cues guiding the axons and dendrites. Our group was pioneer in describing that one of these signals are the extracellular purines. We found that extracellular ATP, through its selective ionotropic P2X7 receptor (P2X7R), negatively regulates axonal growth and branching. Here, we evaluate if other purinergic compounds, such as the diadenosine pentaphosphate (Ap5A), may module the dynamics of dendritic or axonal growth and branching in cultured hippocampal neurons. Our results show that Ap5A negatively modulates the dendrite's growth and number by inducing transient intracellular calcium increases in the dendrites' growth cone. Interestingly, phenol red, commonly used as a pH indicator in culture media, also blocks the P2X1 receptors, avoided the negative modulation of Ap5A on dendrites. Subsequent pharmacological studies using a battery of selective P2X1R antagonists confirmed the involvement of this subunit. In agreement with pharmacological studies, P2X1R overexpression caused a similar reduction in dendritic length and number as that induced by Ap5A. This effect was reverted when neurons were co-transfected with the vector expressing the interference RNA for P2X1R. Despite small hairpin RNAs reverting the reduction in the number of dendrites caused by Ap5A, it did not avoid the dendritic length decrease induced by the polyphosphate, suggesting, therefore, the involvement of a heteromeric P2X receptor. Our results are indicating that Ap5A exerts a negative influence on dendritic growth.


Assuntos
Trifosfato de Adenosina , Fosfatos de Dinucleosídeos , Receptores Purinérgicos P2 , Trifosfato de Adenosina/farmacologia , Receptores Purinérgicos P2/metabolismo , Neurônios/metabolismo , Dendritos/metabolismo , Hipocampo/metabolismo
2.
Health Econ Policy Law ; 17(4): 428-443, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35670359

RESUMO

INTRODUCTION: Currently, it is not known what attributes of health care interventions citizens consider important in disinvestment decision-making (i.e. decisions to discontinue reimbursement). Therefore, this study aims to investigate the preferences of citizens of the Netherlands toward the relative importance of attributes of health care interventions in the context of disinvestment. METHODS: A participatory value evaluation (PVE) was conducted in April and May 2020. In this PVE, 1143 Dutch citizens were asked to save at least €100 million by selecting health care interventions for disinvestment from a list of eight unlabeled health care interventions, described solely with attributes. A portfolio choice model was used to analyze participants' choices. RESULTS: Participants preferred to disinvest health care interventions resulting in smaller gains in quality of life and life expectancy that are provided to older patient groups. Portfolios (i.e. combinations of health care interventions) resulting in smaller savings were preferred for disinvestment over portfolios with larger savings. CONCLUSION: The disinvestment of health care interventions resulting in smaller health gains and that are targeted at older patient groups is likely to receive most public support. By incorporating this information in the selection of candidate interventions for disinvestment and the communication on disinvestment decisions, policymakers may increase public support for disinvestment.


Assuntos
Atenção à Saúde , Qualidade de Vida , Humanos , Países Baixos
3.
Rev. mex. ing. bioméd ; 41(1): 105-116, ene.-abr. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1139327

RESUMO

Resumen El objetivo de esta investigación es la modelación del dominio de un marco técnico de compartición e interacción de un expediente clínico electrónico (ECE) entre diversas instituciones de salud, públicas o privadas, como primer paso para lograr un marco técnico de refererencia para la interoperabilidad de sistemas de ECE en México. Se ha utilizado el proceso sistemático KMOS-RE para obterner los diversos artefactos que conforman el modelo: el léxico extendido del conocimiento del domino, los modelos conceptuales del dominio de aplicación y del dominio de la solución y los modelos de estados. Debido a que el diseño e implementación de los sistemas de ECE de cada una de las instituciones de salud se generan de manera independiente, realizar un marco técnico de referencia representa un gran desafío y una gran oportunidad, ya que ofrecerá ventajas importantes, como el hecho de contar con la información clínica de manera oportuna en cualquier institución de salud, la posibilidad de que el propio paciente acceda a su información y la facilidad de realizar investigación clínica a partir de los datos compartidos. Aún cuando la modelación de un dominio es dinámica, el contar con un modelo del dominio lo más preciso posible en este punto, facilitará los siguientes pasos para lograr el marco técnico de referencia propuesto.


Abstract This paper presents the domain modeling of a technical framework of sharing and interaction of an electronic medical record among different healthcare institutions, both public or private, as a first step to establish a technical reference framework for the interoperability of electronic medical record systems in Mexico. The artefact that make up the domain model were carried out using the KMOS-RE systematic process. Through this process, the following components have been obtained: the knowledge domain extended lexicon, the conceptual models, one for the application domain and another for the solution domain, as well as the state models. Since the design and implementation of the electronic medical record systems of different healthcare institutions are generated independently, having a technical reference framework represents a great challenge but also a great opportunity, since it will offer important advantages, such as having the clinical information in a timely manner in any healthcare institution, the possibility of the patient accessing their own information and the ease of conducting clinical research from the shared data. Even when a domain modeling is a dynamic task, having a precise domain model at this point will facilitate the next steps to achieve the proposed technical reference framework.

4.
Vet Anim Sci ; 7: 100044, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32734066

RESUMO

A total of 32 Pasteurella multocida isolates were obtained from 60 cases of swine pneumonic lungs collected in "Castilla y León" (northwestern Spain) between November 2017 and April 2018. Capsular type A isolates were isolated from 96.9% cases and capsular type D from the remaining 3.1%. All isolates were characterized for their susceptibilities to eight antimicrobial agents and the presence of eight resistance genes. The frequency of susceptibility was lower than 60% in four of the drugs, 84.4% of the isolates showed resistance to at least two compounds, and 46.9% to a combination of three drugs. The resistance patterns suggested that enrofloxacin, chloramphenicol, tetracycline and cefotaxime were the compounds most likely active to P. multocida. The usage of PCR revealed that ermC, bla ROB1, tetB and msrE genes occurred in more than 37.0% isolates, that suggested its putative accountability in the resistance of the strains harbor them. However, most were detected in susceptible strains and only a genetic explanation for the resistance could be linked to erythromycin. Therefore, the resistances to clyndamicin, cotrimoxazol, ß-lactams and tetracyclin observed by phenotypic testing remains genetically unexplained and further investigations are required.

5.
Nature ; 563(7731): 365-368, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30429552

RESUMO

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

6.
Mol Biol Cell ; 22(7): 1014-24, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21289095

RESUMO

Axonal growth is essential for establishing neuronal circuits during brain development and for regenerative processes in the adult brain. Unfortunately, the extracellular signals controlling axonal growth are poorly understood. Here we report that a reduction in extracellular ATP levels by tissue-nonspecific alkaline phosphatase (TNAP) is essential for the development of neuritic processes by cultured hippocampal neurons. Selective blockade of TNAP activity with levamisole or specific TNAP knockdown with short hairpin RNA interference inhibited the growth and branching of principal axons, whereas addition of alkaline phosphatase (ALP) promoted axonal growth. Neither activation nor inhibition of adenosine receptors affected the axonal growth, excluding the contribution of extracellular adenosine as a potential hydrolysis product of extracellular ATP to the TNAP-mediated effects. TNAP was colocalized at axonal growth cones with ionotropic ATP receptors (P2X7 receptor), whose activation inhibited axonal growth. Additional analyses suggested a close functional interrelation of TNAP and P2X7 receptors whereby TNAP prevents P2X7 receptor activation by hydrolyzing ATP in the immediate environment of the receptor. Furthermore inhibition of P2X7 receptor reduced TNAP expression, whereas addition of ALP enhanced P2X7 receptor expression. Our results demonstrate that TNAP, regulating both ligand availability and protein expression of P2X7 receptor, is essential for axonal development.


Assuntos
Fosfatase Alcalina/metabolismo , Axônios/fisiologia , Hipocampo/citologia , Neurônios/ultraestrutura , Adenosina/metabolismo , Adjuvantes Imunológicos/farmacologia , Fosfatase Alcalina/genética , Animais , Axônios/ultraestrutura , Células Cultivadas , Dendritos/fisiologia , Dendritos/ultraestrutura , Humanos , Levamisol/farmacologia , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , RNA Interferente Pequeno/metabolismo , Receptores Purinérgicos P2X7/metabolismo
7.
Cell Death Differ ; 14(6): 1211-21, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17347665

RESUMO

In neurons, DNA is prone to free radical damage, although repair mechanisms preserve the genomic integrity. However, activation of the DNA repair system, poly(ADP-ribose) polymerase (PARP-1), is thought to cause neuronal death through NAD+ depletion and mitochondrial membrane potential (delta psi(m)) depolarization. Here, we show that abolishing PARP-1 activity in primary cortical neurons can either enhance or prevent apoptotic death, depending on the intensity of an oxidative stress. Only in severe oxidative stress does PARP-1 activation result in NAD+ and ATP depletion and neuronal death. To investigate the role of PARP-1 in an endogenous model of oxidative stress, we used an RNA interference (RNAi) strategy to specifically knock down glutamate-cysteine ligase (GCL), the rate-limiting enzyme of glutathione biosynthesis. GCL RNAi spontaneously elicited a mild type of oxidative stress that was enough to stimulate PARP-1 in a Ca2+-calmodulin kinase II-dependent manner. GCL RNAi-mediated PARP-1 activation facilitated DNA repair, although neurons underwent delta psi(m) loss followed by some apoptotic death. PARP-1 inhibition did not prevent delta psi(m) loss, but enhanced the vulnerability of neurons to apoptosis upon GCL silencing. Conversely, mild expression of PARP-1 partially prevented to GCL RNAi-dependent apoptosis. Thus, in the mild progressive damage likely occur in neurodegenerative diseases, PARP-1 activation plays a neuroprotective role that should be taken into account when considering therapeutic strategies.


Assuntos
Apoptose/fisiologia , Neurônios/metabolismo , Estresse Oxidativo/fisiologia , Poli(ADP-Ribose) Polimerases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Reparo do DNA , Relação Dose-Resposta a Droga , Citometria de Fluxo , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Mutagênese Sítio-Dirigida , NAD/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/genética , Interferência de RNA , Ratos , Ratos Endogâmicos WF
8.
Am J Respir Crit Care Med ; 156(2 Pt 1): 665-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9279256

RESUMO

IgA nephropathy is a common form of glomerulonephritis, classically manifested by asymptomatic hematuria. Although the exact pathophysiologic mechanism is still unknown, renal damage has been related to mesangial deposition of IgA-containing immune complexes. In recent years, some lung diseases have been associated with IgA nephropathy, including pulmonary hemorrhage and sarcoidosis. We report a patient with idiopathic bronchiolitis obliterans who developed a rapidly progressive glomerulonephritis due to IgA deposits. Extensive deposits of IgA were also found in the lungs, thus suggesting a pathogenetic role for IgA in tissue injury at both organ levels. To our knowledge this association has not been previously described in the literature.


Assuntos
Doença Antimembrana Basal Glomerular/etiologia , Bronquiolite Obliterante/complicações , Glomerulonefrite por IGA/complicações , Idoso , Doença Antimembrana Basal Glomerular/diagnóstico , Doença Antimembrana Basal Glomerular/patologia , Complexo Antígeno-Anticorpo/análise , Biópsia , Bronquiolite Obliterante/diagnóstico , Bronquiolite Obliterante/patologia , Evolução Fatal , Mesângio Glomerular/imunologia , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/patologia , Humanos , Imunoglobulina A/análise , Rim/patologia , Pulmão/patologia , Masculino
9.
J Med Primatol ; 23(1): 16-22, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7932634

RESUMO

Examination of temperature-metabolism relations found no significant differences between thermoregulation of temperature housed laboratory cotton-top tamarins (Saguinus oedipus) and wild tamarins in Colombia, S.A. The results indicate that tamarins do not acclimate to a temperature environment and are metabolically stressed at Ta less than 32 degrees C. This is consistent with an hypothesis of chronic metabolic stress as a factor in the etiology of cotton-top tamarin colitis, which is restricted to captive populations and not found in wild tamarins.


Assuntos
Aclimatação/fisiologia , Regulação da Temperatura Corporal/fisiologia , Colite Ulcerativa/veterinária , Doenças dos Macacos/etiologia , Saguinus/fisiologia , Análise de Variância , Animais , Metabolismo Basal , Clima Frio/efeitos adversos , Colite Ulcerativa/etiologia , Desidratação/complicações , Feminino , Masculino , Modelos Biológicos , Consumo de Oxigênio , Análise de Regressão , Estresse Fisiológico/complicações , Estresse Fisiológico/etiologia
10.
P R Health Sci J ; 12(4): 273-6, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8140206

RESUMO

In this study, ethylcellulose was evaluated as a carrier for the preparation of sustained release of acetaminophen via solid dispersion technique. Physical mixture at the same level of acetaminophen and ethylcellulose was prepared. Differential scanning calorimetry and scanning electron microscope were used to characterize the physical properties of the various systems and to determine if there is possible interaction between acetaminophen and ethylcellulose.


Assuntos
Acetaminofen/química , Celulose/análogos & derivados , Acetaminofen/administração & dosagem , Varredura Diferencial de Calorimetria , Celulose/química , Preparações de Ação Retardada , Microscopia Eletrônica de Varredura
11.
P. R. health sci. j ; 12(4): 273-6, dic. 1993.
Artigo em Inglês | LILACS | ID: lil-176748

RESUMO

In this study, ethylcellulose was evaluated as a carrier for the preparation of sustained release of acetaminophen via solid dispersion technique. Physical mixture at the same level of acetaminophen and ethylcellulose was prepared. Differential scanning calorimetry and scanning electron microscope were used to characterize the physical properties of the various systems and to determine if there is possible interaction between acetaminophen and ethylcellulose


Assuntos
Acetaminofen/química , Celulose/análogos & derivados , Acetaminofen/administração & dosagem , Varredura Diferencial de Calorimetria , Celulose/química , Preparações de Ação Retardada , Microscopia Eletrônica de Varredura
12.
P R Health Sci J ; 11(3): 159-62, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1475345

RESUMO

In this study ethylcellulose was evaluated as a carrier for preparation of prolonged release acetaminophen tablets. Solid dispersions containing three levels of ethylcellulose and acetaminophen (1:3; 1:1; 3:1) were prepared by the solvent method. Also physical mixtures at the same level of ethylcellulose and acetaminophen were prepared. Systems composed of solid dispersion or physical mixture containing the equivalent weight of 50 mg acetaminophen, Emcompress as diluent and 1% magnesium stearate as lubricant were compressed into tablets and tested for dissolution. The dissolution data showed that the drug release decreased as the level of ethylcellulose increased in the solid dispersion formulations. The drug release from tablets prepared with solid dispersion followed the diffusion controlled model for inert porous matrix, while the drug release from tablets prepared with physical mixture followed the first-order kinetic model.


Assuntos
Acetaminofen/administração & dosagem , Celulose/análogos & derivados , Acetaminofen/metabolismo , Celulose/administração & dosagem , Celulose/farmacologia , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Portadores de Fármacos , Composição de Medicamentos , Humanos
13.
P. R. health sci. j ; 11(3): 159-62, dic. 1992.
Artigo em Inglês | LILACS | ID: lil-176765

RESUMO

In this study ethylcellulose was evaluated as a carrier for preparation of prolonged release acetaminophen tablets. Solid dispersions containing three levels of ethylcellulose and acetaminophen (1:3; 1:1; 3:1) were prepared by the solvent method. Also physical mixtures at the same level of ethylcellulose and acetaminophen were prepared. Systems composed of solid dispersion or physical mixture containing the equivalent weight of 50 mg acetaminophen, Emcompress as diluent and 1 per cent magnesium stearate as lubricant were compressed into tablets and tested for dissolution. The dissolution data showed that the drug release decreased as the level of ethylcellulose increased in the solid dispersion formulations. The drug release from tablets prepared with solid dispersion followed the diffusion controlled model for inert porous matrix, while the drug release from tablets prepared with physical mixture followed the first-order kinetic model


Assuntos
Humanos , Acetaminofen/administração & dosagem , Celulose/análogos & derivados , Acetaminofen/metabolismo , Celulose/administração & dosagem , Celulose/farmacologia , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Portadores de Fármacos , Composição de Medicamentos
14.
Cancer ; 54(12): 2968-72, 1984 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-6498770

RESUMO

Histiocytic medullary reticulosis (HMR) was originally defined as a neoplastic disorder. Some cases reported as HMR have been characterized by a systemic proliferation of mature histiocytes showing hemophagocytosis, bone marrow necrosis, pancytopenia, hepatitis, and coagulopathy. Clinically, these patients have fever and constitutional symptoms and often have hepatosplenomegaly and lymphadenopathy. Although there is a high mortality rate, this process appears to be reactive and has been associated with active viral infection. Similar cases have been briefly described that were associated with other agents or disease processes, but concomitant viral infections were not excluded. Three characteristic examples of this hemophagocytic syndrome that were associated with bacterial sepsis are described. Active infection by those viruses that have previously been associated with the syndrome was excluded. It appears that the hemophagocytic syndrome may be associated with various types of active disseminated infections.


Assuntos
Infecções Bacterianas/complicações , Doenças Linfáticas/etiologia , Adulto , Idoso , Medula Óssea/patologia , Feminino , Histiócitos/patologia , Humanos , Doenças Linfáticas/patologia , Masculino , Pessoa de Meia-Idade , Viroses/complicações
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