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1.
Phys Rev Lett ; 123(14): 141301, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31702225

RESUMO

In hierarchical models of structure formation, the first galaxies form in low-mass dark matter potential wells, probing the behavior of dark matter on kiloparsec scales. Even though these objects are below the detection threshold of current telescopes, future missions will open an observational window into this emergent world. In this Letter, we investigate how the first galaxies are assembled in a "fuzzy" dark matter (FDM) cosmology where dark matter is an ultralight ∼10^{-22} eV boson and the primordial stars are expected to form along dense dark matter filaments. Using a first-of-its-kind cosmological hydrodynamical simulation, we explore the interplay between baryonic physics and unique wavelike features inherent to FDM. In our simulation, the dark matter filaments show coherent interference patterns on the boson de Broglie scale and develop cylindrical solitonlike cores, which are unstable under gravity and collapse into kiloparsec-scale spherical solitons. Features of the dark matter distribution are largely unaffected by the baryonic feedback. On the contrary, the distributions of gas and stars, which do form along the entire filament, exhibit central cores imprinted by dark matter-a smoking gun signature of FDM.

2.
Cereb Cortex ; 24(6): 1579-88, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23365213

RESUMO

In the cerebral cortex, most synapses are found in the neuropil, but relatively little is known about their 3-dimensional organization. Using an automated dual-beam electron microscope that combines focused ion beam milling and scanning electron microscopy, we have been able to obtain 10 three-dimensional samples with an average volume of 180 µm(3) from the neuropil of layer III of the young rat somatosensory cortex (hindlimb representation). We have used specific software tools to fully reconstruct 1695 synaptic junctions present in these samples and to accurately quantify the number of synapses per unit volume. These tools also allowed us to determine synapse position and to analyze their spatial distribution using spatial statistical methods. Our results indicate that the distribution of synaptic junctions in the neuropil is nearly random, only constrained by the fact that synapses cannot overlap in space. A theoretical model based on random sequential absorption, which closely reproduces the actual distribution of synapses, is also presented.


Assuntos
Imageamento Tridimensional , Microscopia Eletrônica/métodos , Modelos Neurológicos , Neurônios/ultraestrutura , Córtex Somatossensorial/ultraestrutura , Sinapses/ultraestrutura , Algoritmos , Animais , Processamento Eletrônico de Dados , Masculino , Neurópilo/ultraestrutura , Ratos Wistar , Software
3.
J Am Chem Soc ; 136(44): 15676-83, 2014 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25317660

RESUMO

An artificial imine reductase results upon incorporation of a biotinylated Cp*Ir moiety (Cp* = C5Me5(-)) within homotetrameric streptavidin (Sav) (referred to as Cp*Ir(Biot-p-L)Cl] ⊂ Sav). Mutation of S112 reveals a marked effect of the Ir/streptavidin ratio on both the saturation kinetics as well as the enantioselectivity for the production of salsolidine. For [Cp*Ir(Biot-p-L)Cl] ⊂ S112A Sav, both the reaction rate and the selectivity (up to 96% ee (R)-salsolidine, kcat 14-4 min(-1) vs [Ir], KM 65-370 mM) decrease upon fully saturating all biotin binding sites (the ee varying between 96% ee and 45% ee R). In contrast, for [Cp*Ir(Biot-p-L)Cl] ⊂ S112K Sav, both the rate and the selectivity remain nearly constant upon varying the Ir/streptavidin ratio [up to 78% ee (S)-salsolidine, kcat 2.6 min(-1), KM 95 mM]. X-ray analysis complemented with docking studies highlight a marked preference of the S112A and S112K Sav mutants for the SIr and RIr enantiomeric forms of the cofactor, respectively. Combining both docking and saturation kinetic studies led to the formulation of an enantioselection mechanism relying on an "induced lock-and-key" hypothesis: the host protein dictates the configuration of the biotinylated Ir-cofactor which, in turn, by and large determines the enantioselectivity of the imine reductase.


Assuntos
Biotina/química , Iminas/química , Oxirredutases/química , Estreptavidina/química , Cinética , Simulação de Acoplamento Molecular , Conformação Proteica
4.
J Biol Inorg Chem ; 19(3): 439-47, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24442915

RESUMO

Three forms of lactoferrin (Lf) that differed in their levels of iron loading (Lf, LfFe, and LfFe2) were simultaneously labeled with the fluorophores AF350 and AF430. All three resulting fluorescent lactoferrins exhibited fluorescence resonance energy transfer (FRET), but they all presented different FRET patterns. Whereas only partial FRET was observed for Lf and LfFe, practically complete FRET was seen for the holo form (LfFe2). For each form of metal-loaded lactoferrin, the AF350-AF430 distance varied depending on the protein conformation, which in turn depended on the level of iron loading. Thus, the FRET patterns of these lactoferrins were found to correlate with their iron loading levels. In order to gain greater insight into the number of fluorophores and the different FRET patterns observed (i.e., their iron levels), a computational analysis was performed. The results highlighted a number of lysines that have the greatest influence on the FRET profile. Moreover, despite the lack of an X-ray structure for any LfFe species, our study also showed that this species presents modified subdomain organization of the N-lobe, which narrows its iron-binding site. Complete domain rearrangement occurs during the LfFe to LfFe2 transition. Finally, as an example of the possible applications of the results of this study, we made use of the FRET fingerprints of these fluorescent lactoferrins to monitor the interaction of lactoferrin with a healthy bacterium, namely Bifidobacterium breve. This latter study demonstrated that lactoferrin supplies iron to this bacterium, and suggested that this process occurs with no protein internalization.


Assuntos
Biologia Computacional/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Ferro/análise , Ferro/química , Lactoferrina/análise , Lactoferrina/química , Humanos , Estrutura Secundária de Proteína , Difração de Raios X
5.
Cereb Cortex ; 23(8): 1798-810, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22710613

RESUMO

Dendritic spines of pyramidal neurons are targets of most excitatory synapses in the cerebral cortex. Recent evidence suggests that the morphology of the dendritic spine could determine its synaptic strength and learning rules. However, unfortunately, there are scant data available regarding the detailed morphology of these structures for the human cerebral cortex. In the present study, we analyzed over 8900 individual dendritic spines that were completely 3D reconstructed along the length of apical and basal dendrites of layer III pyramidal neurons in the cingulate cortex of 2 male humans (aged 40 and 85 years old), using intracellular injections of Lucifer Yellow in fixed tissue. We assembled a large, quantitative database, which revealed a major reduction in spine densities in the aged case. Specifically, small and short spines of basal dendrites and long spines of apical dendrites were lost, regardless of the distance from the soma. Given the age difference between the cases, our results suggest selective alterations in spines with aging in humans and indicate that the spine volume and length are regulated by different biological mechanisms.


Assuntos
Fatores Etários , Espinhas Dendríticas/ultraestrutura , Células Piramidais/citologia , Adulto , Idoso de 80 Anos ou mais , Humanos , Imageamento Tridimensional , Masculino
7.
Artif Intell Med ; 143: 102625, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37673566

RESUMO

The wide adoption of electronic health records (EHRs) offers immense potential as a source of support for clinical research. However, previous studies focused on extracting only a limited set of medical concepts to support information extraction in the cancer domain for the Spanish language. Building on the success of deep learning for processing natural language texts, this paper proposes a transformer-based approach to extract named entities from breast cancer clinical notes written in Spanish and compares several language models. To facilitate this approach, a schema for annotating clinical notes with breast cancer concepts is presented, and a corpus for breast cancer is developed. Results indicate that both BERT-based and RoBERTa-based language models demonstrate competitive performance in clinical Named Entity Recognition (NER). Specifically, BETO and multilingual BERT achieve F-scores of 93.71% and 94.63%, respectively. Additionally, RoBERTa Biomedical attains an F-score of 95.01%, while RoBERTa BNE achieves an F-score of 94.54%. The findings suggest that transformers can feasibly extract information in the clinical domain in the Spanish language, with the use of models trained on biomedical texts contributing to enhanced results. The proposed approach takes advantage of transfer learning techniques by fine-tuning language models to automatically represent text features and avoiding the time-consuming feature engineering process.


Assuntos
Neoplasias da Mama , Registros Eletrônicos de Saúde , Multilinguismo , Armazenamento e Recuperação da Informação , Aprendizado Profundo , Processamento de Linguagem Natural
8.
Chembiochem ; 13(2): 240-51, 2012 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-22190469

RESUMO

Here we report the best artificial metalloenzyme to date for the selective oxidation of aromatic alkenes; it was obtained by noncovalent insertion of Mn(III)-meso-tetrakis(p-carboxyphenyl)porphyrin [Mn(TpCPP), 1-Mn] into a host protein, xylanase 10A from Streptomyces lividans (Xln10A). Two metallic complexes-N,N'-ethylene bis(2-hydroxybenzylimine)-5,5'-dicarboxylic acid Mn(III) [(Mn-salen), 2-Mn] and 1-Mn-were associated with Xln10A, and the two hybrid biocatalysts were characterised by UV-visible spectroscopy, circular dichroism and molecular modelling. Only the artificial metalloenzyme based on 1-Mn and Xln10A was studied for its catalytic properties in the oxidation of various substituted styrene derivatives by KHSO(5): after optimisation, the 1-Mn-Xln10A artificial metalloenzyme was able to catalyse the oxidation of para-methoxystyrene by KHSO(5) with a 16 % yield and the best enantioselectivity (80 % in favour of the R isomer) ever reported for an artificial metalloenzyme.


Assuntos
Endo-1,4-beta-Xilanases/química , Compostos de Epóxi/química , Manganês/química , Metaloproteínas/química , Catálise , Dicroísmo Circular , Endo-1,4-beta-Xilanases/metabolismo , Manganês/metabolismo , Metaloproteínas/metabolismo , Modelos Moleculares , Estrutura Molecular , Oxirredução , Espectrofotometria Ultravioleta , Estereoisomerismo , Estireno/química
9.
Rev Med Inst Mex Seguro Soc ; 60(3): 328-337, 2022 May 01.
Artigo em Espanhol | MEDLINE | ID: mdl-35763408

RESUMO

Background: Studies carried out in Mexico show that the COVID-19 pandemic has negatively impacted families in every field. Confinement has generated problems and economic, social and health instability in a large sector of the population, especially in the most vulnerable, to which children and adolescents are part of. Objective: To identify the impact of the confinement and closure of children daycare centers from the Instituto Mexicano del Seguro Social (IMSS) derived from the COVID-19 pandemic. Material and methods: Three questionnaire-type surveys were implemented via email for workers who were users of IMSS children daycare centers from September to November 2020. The surveys had a perception design, one- and two-stage, simple random and with results by segments. Results were obtained for independent proportions. The z-test was applied at 95% confidence. Results: Effects on workers and child users of the service derived from the closure of children daycare centers were observed, and it was greater in entities with closed children daycare centers than with those ones in operation (p < 0.0001). Conclusions: The negative impact derived from the closure of children daycare centers due to the confinement by COVID-19 in workers who use the service and their children was identified. The spheres with the greatest impact were the economic, the working environment, as well as the children's health (and their families).


Introducción: : estudios realizados en México muestran que la pandemia por COVID-19 ha impactado de forma negativa a las familias en todos los ámbitos. El confinamiento ha generado problemas e inestabilidad económica, social y en la salud en un gran sector de la población, especialmente en el más vulnerable, donde se encuentran los niños y adolescentes. Objetivo: identificar el impacto del confinamiento y el cierre de guarderías del Instituto Mexicano del Seguro Social (IMSS) derivado de la pandemia por COVID-19. Material y métodos: se aplicaron vía correo electrónico tres encuestas tipo cuestionario a trabajadores usuarios del servicio de guardería del IMSS de septiembre a noviembre de 2020. Las encuestas tenían diseño de percepción uni y bietápico, aleatorio simple y con resultados por segmentos. Se obtuvieron resultados para proporciones independientes. Se aplicó el z-test con un 95% de confianza. Resultados: se observó afectación en los trabajadores y en los niños usuarios del servicio derivado del cierre de las guarderías del IMSS, la cual fue mayor en las entidades con guarderías cerradas que en aquellas en operación (p < 0.0001). Conclusiones: se identificó el impacto negativo derivado del cierre de guarderías IMSS por el confinamiento por COVID-19 en trabajadores usuarios del servicio y sus hijos. Los ámbitos con más afectación fueron el económico, el laboral, así como la salud de los niños (y sus familias).


Assuntos
COVID-19 , Adolescente , COVID-19/epidemiologia , Criança , Creches , Humanos , México/epidemiologia , Pandemias , Inquéritos e Questionários
10.
Artigo em Espanhol | MEDLINE | ID: mdl-38571969

RESUMO

Objectives: To identify the clinical characteristics, analyze the results and show the efficacy of surgical treatment of hypertrophic obstructive cardiomyopathy (HOC), in a national reference institute. Methods: A descriptive, retrospective, case series of patients with the diagnosis of HOC operated at the National Cardiovascular Institute, was performed between December 2016 and January 2019. We analyzed the postoperative evolution of symptomatology, functional class (FC), left ventricular outflow tract gradient (LVOTG) and mitral regurgitation (MR). Results: Thirteen cases with HOC undergoing extended septal myectomy were evaluated. 31% were women and the average age was 39.6 years. Before surgical treatment, 85% were in functional class (FC) III-IV, 85% of patients had severe MR, the mean septum thickness was 27 mm (range from 19 to 39 mm), and mean LVOTG was 111 mmHg (range from 60 to 150 mmHg). After surgical treatment we found improvement of the functional class (69% in FC I) and the degree of MR (92% with zero or minimal), and reduction of mean LVOTG to 16 mmHg (range from 6 to 35 mmHg). Simultaneous surgery of the mitral valve was performed in 7 patients (54%). Conclusions: Our experience in HOC surgery is good. The treatment of both myocardial and valve components allows reducing LVOTG and correcting MR.

11.
Bol Med Hosp Infant Mex ; 76(4): 193-197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303651

RESUMO

Background: Although in most cases Zika is an uncomplicated febrile disease, in pregnant women is a recognized cause of congenital disorders. Microcephaly is the characteristic most frequently described in the congenital Zika virus syndrome, and the diagnosis requires laboratory confirmation. Case report: A 23-year-old female on the ninth week of pregnancy by date of last menstrual period and 10.3 weeks by ultrasound, attended to Health Services, presenting clinical manifestations of Zika infection, which was later confirmed by laboratory tests. In her 18.6 weeks of pregnancy, a non-mobile single fetus was documented. Additional findings were microcephaly, lack of thorax with cardiac activity, anterior corporal placenta with 30% calcification, and an image of probable venous lake versus placental cyst. She was admitted to the emergency room for late abortion and labor was induced, obtaining an 80 g male product with head circumference of 9 cm. Reverse transcription polymerase chain reaction analysis on the umbilical cord was positive for Zika virus. Conclusions: Zika infection during pregnancy must be suspected and diagnosed promptly to offer comprehensive care. The loss of conception in these patients has been documented with results of chorionic villus biopsies, finding Zika virus RNA and suggesting spontaneous abortion early during viremia.


Introducción: Aunque en la mayoría de los casos la infección por el virus del Zika (ZIKV) causa enfermedad febril sin complicaciones, en mujeres embarazadas es causa reconocida de alteraciones congénitas y muerte fetal. La microcefalia es la característica descrita con mayor frecuencia en el síndrome congénito por este virus. Caso clínico: Paciente de sexo femenino de 23 años de edad que cursaba la novena semana de gestación (SDG) por la fecha de la última menstruación y la 10.3 SDG por ultrasonido. Acudió a los servicios de salud por presentar un cuadro clínico compatible con infección por el ZIKV, la cual se confirmó por estudios de laboratorio. A las 18.6 SDG se documentó feto único sin movimientos, con datos de microcefalia, tórax con área cardiaca sin actividad, placenta corporal anterior con calcificación en el 30% e imagen probable de lago venoso versus quiste placentario. La paciente ingresó en urgencias por aborto diferido. Se indujo el trabajo de parto y se obtuvo por vía vaginal un producto masculino de 80 g, con perímetro cefálico de 9 cm. El análisis del cordón umbilical por la reacción en cadena de la polimerasa con retrotranscriptasa confirmó el diagnóstico de síndrome congénito por ZIKV. Conclusiones: Durante el embarazo debe sospecharse la infección por ZIKV para realizar un diagnóstico oportuno y ofrecer una atención integral. La pérdida del producto de la concepción en estas pacientes se ha documentado, y se ha encontrado ARN del ZIKV en las biopsias de las vellosidades coriónicas, lo que podría sugerir el aborto espontáneo de manera temprana durante la viremia.


Assuntos
Aborto Espontâneo/virologia , Microcefalia/virologia , Complicações Infecciosas na Gravidez/virologia , Infecção por Zika virus/complicações , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Adulto Jovem , Zika virus/isolamento & purificação , Infecção por Zika virus/diagnóstico
12.
Sci Rep ; 8(1): 13088, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30166564

RESUMO

Latanoprost is a common glaucoma medication. Here, we study longitudinal effects of sustained latanoprost treatment on intraocular pressure (IOP) in C57BL/6J mice, as well as two potential side-effects, changes in iris pigmentation and central corneal thickness (CCT). Male C57BL/6J mice were treated daily for 16 weeks with latanoprost. Control mice were treated on the same schedule with the preservative used with latanoprost, benzalkonium chloride (BAK), or handled, without ocular treatments. IOP and CCT were studied at pre-treatment, 2 "early" time points, and 2 "late" time points; slit-lamp analysis performed at a late time point; and expression of corneal and iridial candidate genes analyzed at the end of the experiment. Latanoprost lowered IOP short, but not long-term. Sustained application of BAK consistently resulted in significant corneal thinning, whereas sustained treatment with latanoprost resulted in smaller and less consistent changes. Neither treatment affected iris pigmentation, corneal matrix metalloprotease expression or iridial pigment-related genes expression. In summary, latanoprost initially lowered IOP in C57BL/6J mice, but became less effective with sustained treatment, likely due to physiological adaptation. These results identify a new resource for studying changes in responsiveness associated with long-term treatment with latanoprost and highlight detrimental effects of commonly used preservative BAK.


Assuntos
Câmara Anterior/anatomia & histologia , Câmara Anterior/fisiologia , Latanoprosta/administração & dosagem , Latanoprosta/farmacologia , Animais , Câmara Anterior/efeitos dos fármacos , Compostos de Benzalcônio/farmacologia , Córnea/efeitos dos fármacos , Preparações de Ação Retardada/farmacologia , Pressão Intraocular/efeitos dos fármacos , Iris/efeitos dos fármacos , Iris/fisiologia , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Pigmentação/efeitos dos fármacos , Pigmentação/genética , Fatores de Tempo
13.
Comput Med Imaging Graph ; 55: 87-94, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27507325

RESUMO

The internal limiting membrane (ILM) separates the retina and optic nerve head (ONH) from the vitreous. In the optical coherence tomography volumes of glaucoma patients, while current approaches for the segmentation of the ILM in the peripapillary and macular regions are considered robust, current approaches commonly produce ILM segmentation errors at the ONH due to the presence of blood vessels and/or characteristic glaucomatous deep cupping. Because a precise segmentation of the ILM surface at the ONH is required for computing several newer structural measurements including Bruch's membrane opening-minimum rim width (BMO-MRW) and cup volume, in this study, we propose a multimodal multiresolution graph-based method to precisely segment the ILM surface within ONH-centered spectral-domain optical coherence tomography (SD-OCT) volumes. In particular, the gradient vector flow (GVF) field, which is computed from a multiresolution initial segmentation, is employed for calculating a set of non-overlapping GVF-based columns perpendicular to the initial segmentation. The GVF columns are utilized to resample the volume and also serve as the columns to the graph construction. The ILM surface in the resampled volume is fairly smooth and does not contain the steep slopes. This prior shape knowledge along with the blood vessel information, obtained from registered fundus photographs, are incorporated in a graph-theoretic approach in order to identify the location of the ILM surface. The proposed method is tested on the SD-OCT volumes of 44 subjects with various stages of glaucoma and significantly smaller segmentation errors were obtained than that of current approaches.


Assuntos
Algoritmos , Glaucoma/diagnóstico por imagem , Disco Óptico/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Técnicas de Diagnóstico Oftalmológico , Humanos , Vasos Retinianos/diagnóstico por imagem
14.
Mon Not R Astron Soc ; 471(4): 4559-4570, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28983129

RESUMO

We present a theoretical analysis of some unexplored aspects of relaxed Bose-Einstein condensate dark matter (BECDM) haloes. This type of ultralight bosonic scalar field dark matter is a viable alternative to the standard cold dark matter (CDM) paradigm, as it makes the same large-scale predictions as CDM and potentially overcomes CDM's small-scale problems via a galaxy-scale de Broglie wavelength. We simulate BECDM halo formation through mergers, evolved under the Schrödinger-Poisson equations. The formed haloes consist of a soliton core supported against gravitational collapse by the quantum pressure tensor and an asymptotic r-3 NFW-like profile. We find a fundamental relation of the core-to-halo mass with the dimensionless invariant Ξ ≡ |E|/M3/(Gm/h)2 or Mc/M ≃ 2.6Ξ1/3, linking the soliton to global halo properties. For r ≥ 3.5 rc core radii, we find equipartition between potential, classical kinetic and quantum gradient energies. The haloes also exhibit a conspicuous turbulent behaviour driven by the continuous reconnection of vortex lines due to wave interference. We analyse the turbulence 1D velocity power spectrum and find a k-1.1 power law. This suggests that the vorticity in BECDM haloes is homogeneous, similar to thermally-driven counterflow BEC systems from condensed matter physics, in contrast to a k-5/3 Kolmogorov power law seen in mechanically-driven quantum systems. The mode where the power spectrum peaks is approximately the soliton width, implying that the soliton-sized granules carry most of the turbulent energy in BECDM haloes.

15.
Mon Not R Astron Soc ; 472(3): 2945-2954, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-30595610

RESUMO

We compare a suite of four simulated dwarf galaxies formed in 1010 M☉ haloes of collisionless cold dark matter (CDM) with galaxies simulated in the same haloes with an identical galaxy formation model but a non-zero cross-section for DM self-interactions. These cosmological zoom-in simulations are part of the Feedback In Realistic Environments (fire) project and utilize the fire-2 model for hydrodynamics and galaxy formation physics. We find the stellar masses of the galaxies formed in self-interacting dark matter (SIDM) with σ/m = 1 cm2 g-1 are very similar to those in CDM (spanning M ★ ≈ 105.7-7.0 M☉) and all runs lie on a similar stellar mass-size relation. The logarithmic DM density slope (α = d log ρ/d log r) in the central 250-500 pc remains steeper than α = -0.8 for the CDM-Hydro simulations with stellar mass M ★ ~ 106.6 M☉ and core-like in the most massive galaxy. In contrast, every SIDM hydrodynamic simulation yields a flatter profile, with α > -0.4. Moreover, the central density profiles predicted in SIDM runs without baryons are similar to the SIDM runs that include fire-2 baryonic physics. Thus, SIDM appears to be much more robust to the inclusion of (potentially uncertain) baryonic physics than CDM on this mass scale, suggesting that SIDM will be easier to falsify than CDM using low-mass galaxies. Our fire simulations predict that galaxies less massive than M ★ ≲ 3 × 106 M☉ provide potentially ideal targets for discriminating models, with SIDM producing substantial cores in such tiny galaxies and CDM producing cusps.

16.
Perinatol. reprod. hum ; 35(3): 89-98, sep.-dic. 2021. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1406191

RESUMO

Resumen Introducción: Los gramnegativos continúan siendo los causantes de infecciones asociadas a la atención a la salud (IAAS). Material y métodos:: Analizamos la resistencia antimicrobiana de patógenos durante el 2013 vs. 2018 y lo comparamos con lo publicado en 2006 vs. 2012. Resultados: Identificamos nueve patógenos gramnegativos, de un total de 404 aislamientos, con una prevalencia en 2013 (N = 227 [0.22]) vs. 2018 (N = 177 [0.17]) y una incidencia por egresos (6,607 en el 2013 y 7,778 en el 2018) del 3.4 y 2.2% respectivamente. Destacaron tres patógenos: Klebsiella pneumoniae (129 [31.93%]), Pseudomonas aeruginosa (85 [21.03%]) y Escherichia coli (80 [19.80%]). Estos, llamados patógenos ESKAPE-E, prevalecieron como causantes de IAAS. Identificamos un aumento en los patrones de resistencia para muchos patógenos en 2018. Conclusión: La multirresistencia a patógenos ESKAPE-E es un serio problema de salud pública, por carecer de alternativas terapéuticas para enfrentar este reto. Los mapas de resistencia bacteriana ayudan en la prescripción antibiótica.


Abstract Background: Gram-negatives continue to be the cause of infections associated with health care (HCAI). Material and methods: We analyzed the antimicrobial resistance of pathogens during 2013 vs. 2018 and we compare it with what was published in 2006 vs. 2012. Results: We identified 9 gram-negative pathogens, out of a total of 404 isolates, with a prevalence in 2013 (N = 227 [0.22]) vs. 2018 (N = 177 [0.17]) and an incidence due to discharges (6,607 in 2013 and 7,778 in 2018) of 3.4 and 2.2%, respectively.Three pathogens stood out Klebsiella pneumoniae (129 [31.93%]), Pseudomonas aeruginosa (85 [21.03%]) and Escherichia coli (80 [19.80%]). These, called ESKAPE-E pathogens, prevailed as the cause of HCAI. We identified an increase in resistance patterns for many pathogens in 2018. Conclusion: Multi-resistance to ESKAPE-E pathogens is a serious public health problem, due to the lack of therapeutic alternatives to face this challenge. Bacterial resistance maps help in antibiotic prescription.

17.
Orinoquia ; 24(2): 51-78, July-Dec. 2020. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1250435

RESUMO

Resumen La crioconservación es una herramienta biotecnológica que en peces está orientada principalmente a la conservación criogénica de semen como estrategia de preservación del recurso genético y a su uso para la producción de alevinos con fines diferentes. Actualmente, los protocolos de crioconservación seminal en peces de agua dulce establecen una amplia variedad de procedimientos cuya efectividad se basa en aspectos ligados a la calidad seminal post-descongelación y la fertilidad, así como su relación con el desarrollo de la progenie. El efecto de la conservación del semen en nitrógeno líquido por periodos amplios de tiempo también toma importancia en ésta biotecnología. Por lo anterior, el objetivo de la presente revisión es describir aspectos biotecnológicos, celulares y bioquímicos asociados al proceso de crioconservación seminal en peces dulceacuícolas, resaltando los avances, las limitaciones y sus perspectivas.


Abstract Cryopreservation is a biotechnological tool that in fish is mainly aimed at cryogenic conservation of semen as a strategy for preserving the genetic resource and its use for the production of fingerlings with different purposes. Currently, seminal cryopreservation protocols in freshwater fish establish a wide variety of procedures whose effectiveness is based on aspects linked to seminal post-thaw quality and fertility, as well as its relationship with the development of the progeny. The effect of preserving semen in liquid nitrogen for extended periods of time also plays an important role in this biotechnology. Therefore, the objective of this review is to describe biotechnological, cellular and biochemical aspects associated with the seminal cryopreservation process in freshwater fish, highlighting the advances, limitations and perspectives.


Resumo A criopreservação é uma ferramenta biotecnológica que em peixes visa principalmente a conservação criogênica do sêmen como estratégia para a preservação do recurso genético e sua utilização para a produção de alevinos para diferentes fins. Atualmente, os protocolos de criopreservação seminal em peixes de água doce estabelecem uma ampla variedade de procedimentos cuja eficácia se baseia em aspectos relacionados à qualidade e fertilidade pós-descongelamento seminal, bem como sua relação com o desenvolvimento da progênie. O efeito da preservação do sêmen no nitrogênio líquido por longos períodos de tempo também desempenha um papel importante nessa biotecnologia. Portanto, o objetivo desta revisão é descrever aspectos biotecnológicos, celulares e bioquímicos associados ao processo de criopreservação seminal em peixes de água doce, destacando os avanços, limitações e perspectivas.

18.
Vascul Pharmacol ; 74: 151-157, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26122664

RESUMO

INTRODUCTION: Acenocoumarol (ACN) has a narrow therapeutic range that is especially difficult to control at the start of its administration. Various dosing pharmacogenetic-guided dosing algorithms have been developed, but further work on their external validation is required. The aim of this study was to evaluate the extrapolation of pharmacogenetic algorithms for ACN as an alternative to the development of a specific algorithm for a given population. MATERIAL AND METHODS: The predictive performance, deviation, accuracy, and clinical significance of five pharmacogenetic algorithms (EU-PACT, Borobia, Rathore, Markatos, Krishna Kumar) were compared in 189 stable ACN patients representing all indications for anticoagulant treatment. RESULTS: The correlation between the dose predictions of the five pharmacogenetic models ranged from 7.7 to 70.6% and the percentage of patients with a correct prediction (deviation ≤20% from actual ACN dose) ranged from 5.9 to 40.7%. EU-PACT and Borobia pharmacogenetic dosing algorithms were the most accurate in our setting and evidenced the best clinical performance. CONCLUSIONS: Among the five models studied, the EU-PACT and Borobia pharmacogenetic dosing algorithms demonstrated the best potential for extrapolation.


Assuntos
Acenocumarol/uso terapêutico , Anticoagulantes/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Farmacogenética/métodos
19.
Artif Intell Med ; 31(2): 117-36, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15219290

RESUMO

Successful secondary structure predictions provide a starting point for direct tertiary structure modelling, and also can significantly improve sequence analysis and sequence-structure threading for aiding in structure and function determination. Hence the improvement of predictive accuracy of the secondary structure prediction becomes essential for future development of the whole field of protein research. In this work we present several multi-classifiers that combine the predictions of the best current classifiers available on Internet. Our results prove that combining the predictions of a set of classifiers by creating composite classifiers is a fruitful one. We have created multi-classifiers that are more accurate than any of the component classifiers. The multi-classifiers are based on Bayesian networks. They are validated with 9 different datasets. Their predictive accuracy results outperform the best secondary structure predictors by 1.21% on average. Our main contributions are: (i) we improved the best know predictive accuracy by 1.21%, (ii) our best results have been obtained with a new semi naïve Bayes approach named Pazzani-EDA and (iii) our multi-classifiers combine results of previously build classifiers predictions obtained through Internet, thanks to our development of a Java application.


Assuntos
Bases de Dados Factuais , Internet , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Teorema de Bayes , Previsões , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Bol. méd. Hosp. Infant. Méx ; 76(4): 193-197, jul.-ago. 2019. tab
Artigo em Espanhol | LILACS | ID: biblio-1089130

RESUMO

Resumen Introducción: Aunque en la mayoría de los casos la infección por el virus del Zika (ZIKV) causa enfermedad febril sin complicaciones, en mujeres embarazadas es causa reconocida de alteraciones congénitas y muerte fetal. La microcefalia es la característica descrita con mayor frecuencia en el síndrome congénito por este virus. Caso clínico: Paciente de sexo femenino de 23 años de edad que cursaba la novena semana de gestación (SDG) por la fecha de la última menstruación y la 10.3 SDG por ultrasonido. Acudió a los servicios de salud por presentar un cuadro clínico compatible con infección por el ZIKV, la cual se confirmó por estudios de laboratorio. A las 18.6 SDG se documentó feto único sin movimientos, con datos de microcefalia, tórax con área cardiaca sin actividad, placenta corporal anterior con calcificación en el 30% e imagen probable de lago venoso versus quiste placentario. La paciente ingresó en urgencias por aborto diferido. Se indujo el trabajo de parto y se obtuvo por vía vaginal un producto masculino de 80 g, con perímetro cefálico de 9 cm. El análisis del cordón umbilical por la reacción en cadena de la polimerasa con retrotranscriptasa confirmó el diagnóstico de síndrome congénito por ZIKV. Conclusiones: Durante el embarazo debe sospecharse la infección por ZIKV para realizar un diagnóstico oportuno y ofrecer una atención integral. La pérdida del producto de la concepción en estas pacientes se ha documentado, y se ha encontrado ARN del ZIKV en las biopsias de las vellosidades coriónicas, lo que podría sugerir el aborto espontáneo de manera temprana durante la viremia.


Abstract Background: Although in most cases Zika is an uncomplicated febrile disease, in pregnant women is a recognized cause of congenital disorders. Microcephaly is the characteristic most frequently described in the congenital Zika virus syndrome, and the diagnosis requires laboratory confirmation. Case report: A 23-year-old female on the ninth week of pregnancy by date of last menstrual period and 10.3 weeks by ultrasound, attended to Health Services, presenting clinical manifestations of Zika infection, which was later confirmed by laboratory tests. In her 18.6 weeks of pregnancy, a non-mobile single fetus was documented. Additional findings were microcephaly, lack of thorax with cardiac activity, anterior corporal placenta with 30% calcification, and an image of probable venous lake versus placental cyst. She was admitted to the emergency room for late abortion and labor was induced, obtaining an 80 g male product with head circumference of 9 cm. Reverse transcription polymerase chain reaction analysis on the umbilical cord was positive for Zika virus. Conclusions: Zika infection during pregnancy must be suspected and diagnosed promptly to offer comprehensive care. The loss of conception in these patients has been documented with results of chorionic villus biopsies, finding Zika virus RNA and suggesting spontaneous abortion early during viremia.


Assuntos
Feminino , Humanos , Gravidez , Adulto Jovem , Complicações Infecciosas na Gravidez/virologia , Aborto Espontâneo/virologia , Infecção por Zika virus/complicações , Microcefalia/virologia , Complicações Infecciosas na Gravidez/diagnóstico , Zika virus/isolamento & purificação , Infecção por Zika virus/diagnóstico
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