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1.
World J Stem Cells ; 15(7): 701-712, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37545756

RESUMO

BACKGROUND: Mesenchymal stromal cells (MSCs) are multipotent cell populations obtained from fetal and adult tissues. They share some characteristics with limb bud mesodermal cells such as differentiation potential into osteogenic, chondrogenic, and tenogenic lineages and an embryonic mesodermal origin. Although MSCs differentiate into skeletal-related lineages in vitro, they have not been shown to self-organize into complex skeletal structures or connective tissues, as in the limb. In this work, we demonstrate that the expression of molecular markers to commit MSCs to skeletal lineages is not sufficient to generate skeletal elements in vivo. AIM: To evaluate the potential of MSCs to differentiate into skeletal lineages and generate complex skeletal structures using the recombinant limb (RL) system. METHODS: We used the experimental system of RLs from dissociated-reaggregated human placenta (PL) and umbilical cord blood (UCB) MSCs. After being harvested and reaggregated in a pellet, cultured cells were introduced into an ectodermal cover obtained from an early chicken limb bud. Next, this filled ectoderm was grafted into the back of a donor chick embryo. Under these conditions, the cells received and responded to the ectoderm's embryonic signals in a spatiotemporal manner to differentiate and pattern into skeletal elements. Their response to differentiation and morphogenetic signals was evaluated by quantitative polymerase chain reaction, histology, immunofluorescence, scanning electron microscopy, and in situ hybridization. RESULTS: We found that human PL-MSCs and UCB-MSCs constituting the RLs expressed chondrogenic, osteogenic, and tenogenic molecular markers while differentially committing into limb lineages but could not generate complex structures in vivo. MSCs-RL from PL or UCB were committed early to chondrogenic lineage. Nevertheless, the UCB-RL osteogenic commitment was favored, although preferentially to a tenogenic cell fate. These findings suggest that the commitment of MSCs to differentiate into skeletal lineages differs according to the source and is independent of their capacity to generate skeletal elements or connective tissue in vivo. Our results suggest that the failure to form skeletal structures may be due to the intrinsic characteristics of MSCs. Thus, it is necessary to thoroughly evaluate the biological aspects of MSCs and how they respond to morphogenetic signals in an in vivo context. CONCLUSION: PL-MSCs and UCB-MSCs express molecular markers of differentiation into skeletal lineages, but they are not sufficient to generate complex skeletal structures in vivo.

2.
Sensors (Basel) ; 21(14)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34300513

RESUMO

Large cities have a significant area of buildings with roofs that are not used most of the time. Vertical-axis wind turbines are suitable for this kind of on-site renewable energy generation. Since wind speeds are not high in these cities, a suitable solution to improve energy generation is to add a Wind Booster. This paper presents a methodology useful for selecting and optimizing the main components of a Wind Booster. As a case of study, we present this methodology in a Wind Booster for a Vertical Axis Wind Turbine (VAWT) that considers the wind flow's specific behavior in a particular city. The final Wind Booster design is state of the art and makes use of Computational Fluid Dynamics (CFD) and Design of Experiments (DOE) techniques. We experimented with the conditions of Mexico City, obtaining a 35.23% increase in torque with the optimized Wind Booster configuration. The results obtained show the potential of this methodology to improve the performance of this kind of system. Moreover, since wind behavior is very different in each city, our proposal could be beneficial for researchers looking to implement the best possible wind turbine in their locality.

3.
Proc Math Phys Eng Sci ; 477(2252): 20210203, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35153573

RESUMO

We introduce relativistic multi-party biased die-rolling protocols, generalizing coin flipping to M ≥ 2 parties and to N ≥ 2 outcomes for any chosen outcome biases and show them unconditionally secure. Our results prove that the most general random secure multi-party computation, where all parties receive the output and there is no secret input by any party, can be implemented with unconditional security. Our protocols extend Kent's (Kent A. 1999 Phys. Rev. Lett. 83, 5382) two-party unbiased coin-flipping protocol, do not require any quantum communication, are practical to implement with current technology and to our knowledge are the first multi-party relativistic cryptographic protocols.

4.
Compr Rev Food Sci Food Saf ; 19(4): 2200-2221, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33337074

RESUMO

Alkalization, also known as "Dutching," is an optional, but very useful, step taken in the production chain of cocoa to darken its color, modify its taste, and increase natural cocoa solubility. Over the years, various attempts have been made to design new and more effective alkalization methods. Moreover, different authors have attempted to elucidate the impact of alkalization on the physicochemical, nutritional, functional, microbiological, and sensory characteristics of alkalized cocoa. The aim of this review is to provide a clear guide about not only the conditions that can be applied to alkalize cocoa, but also the reported effects of alkalization on the nutritional, functional, microbiological, and sensory characteristics of cocoa. The first part of this review describes different cocoa alkalization systems and how they can be tuned to induce specific changes in cocoa properties. The second part is a holistic analysis of the effects of the alkalization process on different cocoa features, performed by emphasizing the biochemistry behind all these transformations.


Assuntos
Cacau/química , Manipulação de Alimentos/métodos , Álcalis/química , Cacau/microbiologia , Cor , Valor Nutritivo , Paladar
5.
Rev Med Inst Mex Seguro Soc ; 55(6): 684-685, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-29190858

RESUMO

On August, the second edition of the Healthcare Book Fair took place, sponsored by the Facultad de Medicina of UNAM. Again, the Revista Médica del Instituto Mexicano del Seguro Social participated with a stand where we promoted it, talked about the different indexes where our journal is included, explained its objective and scope, and finally talked about its nature as an open access journal, which is aimed to the clinical staff of the different health institutions of our country.


El pasado mes de agosto tuvo lugar la segunda edición de la Feria del Libro de Ciencias de la Salud, auspiciada por la Facultad de Medicina de la UNAM. En ella de nueva cuenta tuvo participación la Revista Médica del Instituto Mexicano del Seguro Social con un stand donde se difundió la revista, su indexación en los diferentes índices en los que tenemos participación, se explicitó su objetivo y alcance y se manifestó como una revista de acceso abierto, gratuita, dirigida al personal clínico de las diferentes instituciones de salud del país.


Assuntos
Aniversários e Eventos Especiais , Serviços de Saúde , Publicações Periódicas como Assunto , Academias e Institutos , Livros , Humanos , México , Publicação de Acesso Aberto , Previdência Social
7.
Sci Total Environ ; 506-507: 46-57, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25460938

RESUMO

The integrated use of isotopes (δ(34)S-SO4, δ(18)O-SO4, δ(15)N-NO3, δ(18)O-NO3), taking into account existing hydrogeological knowledge of the study area (mainly hydrochemical), was applied in the Guadalhorce River Basin (southern Spain) to characterise SO4(2-) and NO3(-) sources, and to quantify natural background levels (NBLs) in groundwater bodies. According to Water Framework Directive 2000/60/EC and, more recently, Groundwater Directive 2006/118/EC, it is important to determine NBLs, as their correct assessment is the first, essential step to characterising groundwater bodies, establishing threshold values, assessing chemical status and identifying trends in pollutant concentrations. In many cases, NBLs are high for some parameters and types of groundwater, making it difficult to distinguish clearly between factors of natural or human origin. The main advantages of using stable isotopes in a complex area like the Guadalhorce River Basin that exhibits widely varying hydrogeological and hydrochemical conditions and longstanding anthropogenic influences (mainly agriculture, but also many others) is accurate determination of pollution sources and precise quantification of NBLs. Since chemical analyses only provides the concentration of pollutants in water and not the source, three isotopic sampling campaigns for sulphates (δ(34)S-SO4, δ(18)O-SO4) were carried out, in 2006, 2007 and 2012, and another one was conducted for nitrates (δ(15)N-NO3, δ(18)O-NO3), in 2009, in groundwater bodies in order to trace the origins of each pollutant. The present study identified different pollution sources of dissolved NO3(-) in groundwater using an isotopic composition and quantified the percentage of natural (lithology, chemical and biological processes) and anthropogenic (fertilisers, manure and sewage) SO4(2-) and matched a concentration associated with the percentage in order to determine the NBLs in the basin.


Assuntos
Monitoramento Ambiental/métodos , Rios/química , Poluentes Químicos da Água/análise , Agricultura , Isótopos/análise , Isótopos de Nitrogênio/análise , Espanha , Isótopos de Enxofre/análise
8.
Odontol. pediatr. (Lima) ; 12(2): 102-109, jul.-dic. 2013. tab, ilus
Artigo em Espanhol | LILACS, LIPECS | ID: lil-721917

RESUMO

En la literatura existen reportes sobre las diversas formas de las fosas y fisuras demolares permanentes y premolares. Se conocen las características de éstas y se da por hecho que las estructuras dentales son semejantes en ambas denticiones. Por lo que es necesario abordar el estudio de las características del esmalte de la dentición temporal. Objetivo: Cuantificar la frecuencia de cada forma y profundidad de fosas y fisuras de molares temporales de la clasificación de Nagano. Material y métodos: En un estudio observacional descriptivo ex vivo se analizó una muestra obenida por donación de 101 cortes correspondientes a 67 coronas de molares temporales sin cariesconservadas en agua destilada, pertenecientes a niños mexicanos aparentemente sanos. Las va riables forma y profundidad se identificaron al microscopio estereoscópico por un solo observador (k=.8624). El grosor de los cortes obtenidos por el método de desgaste midieron en promedio 5mm. Resultados: El 28.71% de las fosas y fisuras identificadas corresponden al grupo 5 Características de las “otras formas” de Nagano de fosas y fisuras de molares temporales Features of “other shapes” of Nagano of pit and fissures in primary molars Artículo Original Esther Vaillard Jiménez 1 Enrique E.Huitzil Muñoz Aída Ortega Cambranis 3 S. Abril García Damián 41 Maestra en Estomatología Pediátrica. FEBUAP (México) 2 Maestro en Educación Superior. FEBUAP (México) 3 Maestra en Fisiología. FEBUAP (México) 4 Alumna egresada de la Maestría en C’s estomatológicas en Pediátrica Facultad de Estomatología de la Benemérita Universidad Autónoma de Puebla.


In literature there are reports on the various forms of pits and fissures of permanent molars and pre molars. Their characteristics are known and it is assumed that dental structures are similar in both dentitions. So it is necessary to approach the study of the characteristics of the enamel in primary teeth. Objective: to quantify the frequency of each shape and depth of pits and fissures of molars under the Nagano classification. Material and methods: in an ex vivo observational study a sample obtained by donation of 101 courts to 67 crowns for primary molars without decay preserved in distilled ware is analyzed, this sample belongs to Mexican children with an apparent healthy shape and depth, variables were identified under the stereomicroscope by a single observer (k=8624) The thickness of the slices obtained by the method of wear measured on average o.5 mm. Results: 28.71% of the pits and fissures identified relate to group 5 Nagano. Forms were recognized: flask=4.95%, II=3.96% =3.96 Globe, drop= 3.96% = 2.97%inverted Y, delta = 2.97% and trilobulada= 2.97% zone. According to the depth were identified as medium depth = 48.51%. Deep and surface = 33.66 = 17.82%. Conclusion: There is great variety in the shape and depth of pits and fissures of molars enamel. The high percentage of undescribed forms by Nagano proves to be addressed as a research problem of morph-histological characteristics of the primary dentition.


Assuntos
Feminino , Criança , Dente Decíduo , Dente Decíduo/anormalidades , Fissuras Dentárias , Epidemiologia Descritiva , Estudos Observacionais como Assunto , Estudos Prospectivos , Estudos Transversais
9.
Phys Rev Lett ; 110(21): 210402, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23745844

RESUMO

How much information can a transmitted physical system fundamentally communicate? We introduce the principle of quantum information causality, which states the maximum amount of quantum information that a quantum system can communicate as a function of its dimension, independently of any previously shared quantum physical resources. We present a new quantum information task, whose success probability is upper bounded by the new principle, and show that an optimal strategy to perform it combines the quantum teleportation and superdense coding protocols with a task that has classical inputs.

10.
Pediatr Res ; 69(5 Pt 1): 401-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21283051

RESUMO

Even brief interruption of cardiac compressions significantly reduces critical coronary perfusion pressure during cardiopulmonary resuscitation (CPR). End-tidal CO2 (ETCO2) monitoring may provide a continuous noninvasive method of assessing return of spontaneous circulation (ROSC) without stopping to auscultate for heart rate (HR). However, the ETCO2 value that correlates with an audible HR is unknown. Our objective was to determine the threshold ETCO2 that is associated with ROSC after asphyxia-induced asystole. Neonatal swine (n = 46) were progressively asphyxiated until asystole occurred. Resuscitation followed current neonatal guidelines with initial ventilation with 100% O2 followed by cardiac compressions followed by epinephrine for continued asystole. HR was auscultated every 30 s, and ETCO2 was continuously recorded. A receiver operator curve was generated using the calculated sensitivity and specificity for various ETCO2 values, where a positive test was defined as the presence of HR >60 bpm by auscultation. An ETCO2 cut-off value of 14 mm Hg is the most sensitive ETCO2 value with the least false positives. When using ETCO2 to guide uninterrupted CPR in this model of asphyxia-induced asystole, auscultative confirmation of return of an adequate HR should be performed when ETCO2 ≥ 14 mm Hg is achieved. Correlation during human neonatal CPR needs further investigation.


Assuntos
Asfixia Neonatal/complicações , Testes Respiratórios , Dióxido de Carbono/metabolismo , Reanimação Cardiopulmonar , Expiração , Parada Cardíaca/terapia , Frequência Cardíaca , Agonistas Adrenérgicos/administração & dosagem , Animais , Animais Recém-Nascidos , Asfixia Neonatal/metabolismo , Asfixia Neonatal/fisiopatologia , Biomarcadores/metabolismo , Pressão Sanguínea , Reanimação Cardiopulmonar/métodos , Modelos Animais de Doenças , Epinefrina/administração & dosagem , Parada Cardíaca/etiologia , Parada Cardíaca/metabolismo , Parada Cardíaca/fisiopatologia , Auscultação Cardíaca , Massagem Cardíaca , Humanos , Recém-Nascido , Respiração com Pressão Positiva , Valor Preditivo dos Testes , Sus scrofa , Fatores de Tempo
11.
Pediatr Res ; 61(4): 415-20, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17515864

RESUMO

Despite its use, there is little evidence to support volume infusion (VI) during neonatal cardiopulmonary resuscitation (CPR). This study compares 5% albumin (ALB), normal saline (NS), and no VI (SHAM) on development of pulmonary edema and restoration of mean arterial pressure (MAP) during resuscitation of asphyxiated piglets. Mechanically ventilated swine (n=37, age: 8 +/- 4 d, weight: 2.2 +/- 0.7 kg) were progressively asphyxiated until pH <7.0, Paco2 >100 mm Hg, heart rate (HR) <100 bpm, and MAP <20 mm Hg. After 5 min of ventilatory resuscitation, piglets were randomized blindly to ALB, NS, or SHAM infusion. Animals were recovered for 2 h before euthanasia and lung tissue sampled for wet-to-dry weight ratio (W/D) as a marker of pulmonary edema. SHAM MAP was similar to VI during resuscitation. At 2 h post-resuscitation, MAP of SHAM (48 +/- 13 mm Hg) and ALB (43 +/- 19 mm Hg) was higher than NS (29 +/- 10 mm Hg; p=0.003 and 0.023, respectively). After resuscitation, SHAM piglets had less pulmonary edema (W/D: 5.84 +/- 0.12 versus 5.98 +/- 0.19; p=0.03) and better dynamic compliance (Cd) compared with ALB or NS (Cd: 1.43 +/- 0.69 versus 0.97 +/- 0.37 mL/cm H2O, p=0.018). VI during resuscitation did not improve MAP, and acute recovery of MAP was poorer with NS compared with ALB. VI was associated with increased pulmonary edema. In the absence of hypovolemia, VI during neonatal resuscitation is not beneficial.


Assuntos
Asfixia/terapia , Reanimação Cardiopulmonar , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Masculino , Distribuição Aleatória , Suínos , Porco Miniatura
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