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1.
J Arthroplasty ; 38(11): 2366-2372, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37271227

RESUMO

BACKGROUND: Iliopsoas impingement (IPI) is an important complication after total hip arthroplasty (THA), and anterior cup protrusion is believed to be its main cause; however, the relationship between the hip center of rotation (COR) and symptomatic IPI or cup protrusion remains poorly understood. Therefore, the present study investigated these relationships. METHODS: The medical records of 138 patients who underwent unilateral primary THA were retrospectively reviewed. There were 8 patients (5.8%) who had symptomatic IPI. The COR and cup protrusion length measured with 2 methods were assessed on computed tomography. Risk factors for symptomatic IPI and the relationship between the COR and protrusion length were evaluated. RESULTS: Logistic regression analyses showed that anteroposterior position of the COR, sagittal cup protrusion length (SCPL) at the COR, and both axial and SCPLs at the most anterior margin of the cup were related to symptomatic IPI. Multivariable regression analyses showed that acetabular offset was related to axial protrusion length at the COR, and anteroposterior position of the COR was related to both axial and sagittal protrusion lengths at the most anterior margin of the cup. CONCLUSION: Anterior position of the cup was related to symptomatic IPI and both axial and sagittal protrusion lengths at the most anterior margin of the cup. Anterior reaming and cup protrusion should be avoided as much as possible to prevent symptomatic IPI.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Rotação , Estudos Retrospectivos , Quadril/cirurgia , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Prótese de Quadril/efeitos adversos
2.
J Biosci Bioeng ; 136(1): 58-66, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37188549

RESUMO

Advances in culture-independent microbial analysis, such as metagenomics and single-cell genomics, have significantly increased our understanding of microbial lineages. While these methods have uncovered a large number of novel microbial taxa, many remain uncultured, and their function and mode of existence in the environment are still unknown. This study aims to explore the use of bacteriophage-derived molecules as probes for detecting and isolating uncultured bacteria. Here, we proposed multiplex single-cell sequencing to obtain massive uncultured oral bacterial genomes and searched prophage sequences from over 450 obtained human oral bacterial single-amplified genomes (SAGs). The focus was on the cell wall binding domain (CBD) in phage endolysin, and fluorescent protein-fused CBDs were generated based on several CBD gene sequences predicted from Streptococcus SAGs. The ability of the Streptococcus prophage-derived CBDs to detect and enrich specific Streptococcus species from human saliva while maintaining cell viability was confirmed by magnetic separation and flow cytometry. The approach to phage-derived molecule generation based on uncultured bacterial SAG is expected to improve the process of designing molecules that selectively capture or detect specific bacteria, notably from uncultured gram-positive bacteria, and will have applications in isolation and in situ detection of beneficial or pathogenic bacteria.


Assuntos
Bacteriófagos , Humanos , Bacteriófagos/genética , Bactérias/metabolismo , Genômica , Metagenômica/métodos , Genoma Bacteriano
3.
Elife ; 102021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34132195

RESUMO

Crustacean aquaculture is expected to be a major source of fishery commodities in the near future. Hemocytes are key players of the immune system in shrimps; however, their classification, maturation, and differentiation are still under debate. To date, only discrete and inconsistent information on the classification of shrimp hemocytes has been reported, showing that the morphological characteristics are not sufficient to resolve their actual roles. Our present study using single-cell RNA sequencing revealed six types of hemocytes of Marsupenaeus japonicus based on their transcriptional profiles. We identified markers of each subpopulation and predicted the differentiation pathways involved in their maturation. We also predicted cell growth factors that might play crucial roles in hemocyte differentiation. Different immune roles among these subpopulations were suggested from the analysis of differentially expressed immune-related genes. These results provide a unified classification of shrimp hemocytes, which improves the understanding of its immune system.


Assuntos
Hemócitos , Penaeidae , RNA-Seq/métodos , Análise de Célula Única/métodos , Animais , Proteínas de Artrópodes/análise , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Diferenciação Celular/genética , Feminino , Hemócitos/química , Hemócitos/classificação , Hemócitos/citologia , Hemócitos/metabolismo , Penaeidae/citologia , Penaeidae/genética , Penaeidae/metabolismo
4.
Exp Anim ; 70(1): 84-90, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32999214

RESUMO

Production of chimeric animals is often a necessity for the generation of genetically modified animals and has gained popularity in recent years in regenerative medicine for the reconstruction of xenogeneic organs. Aggregation and injection methods are generally used to produce chimeric mice. In the aggregation method, the chimeras are produced by co-culturing embryos and stem cells, and keeping them physically adhered, although it may not be an assured method for producing chimeric embryos. In the injection method, the chimeras are produced by injecting stem cells into the zona pellucida using microcapillaries; however, this technique requires a high degree of skill. This study aimed to establish a novel method for producing chimeric embryos via water-in-oil droplets that differs from conventional methods. In this study, embryonic stem cells and embryos were successfully isolated in the droplets, and the emergence of chimeric embryos was confirmed by co-culture for 6 h. Using this method, the control and operability of stem cell numbers could be regulated, and reproducibility and quantification were improved during the production of chimeric embryos. In addition to the conventional methods for producing chimeric embryos, the novel method described here could be employed for the efficient production of chimeric animals.


Assuntos
Animais Geneticamente Modificados , Quimera , Técnicas de Cocultura/métodos , Técnicas de Cultura Embrionária/métodos , Embrião de Mamíferos , Células-Tronco Embrionárias , Óleos , Água , Animais , Células Cultivadas , Feminino , Camundongos , Transplante de Células-Tronco/métodos , Zona Pelúcida
5.
Nat Commun ; 11(1): 1442, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188858

RESUMO

Current computers are limited by the von Neumann bottleneck, which constrains the throughput between the processing unit and the memory. Chemical processes have the potential to scale beyond current computing architectures as the processing unit and memory reside in the same space, performing computations through chemical reactions, yet their lack of programmability limits them. Herein, we present a programmable chemical processor comprising of a 5 by 5 array of cells filled with a switchable oscillating chemical (Belousov-Zhabotinsky) reaction. Each cell can be individually addressed in the 'on' or 'off' state, yielding more than 2.9 × 1017 chemical states which arise from the ability to detect distinct amplitudes of oscillations via image processing. By programming the array of interconnected BZ reactions we demonstrate chemically encoded and addressable memory, and we create a chemical Autoencoder for pattern recognition able to perform the equivalent of one million operations per second.

6.
Nat Commun ; 8(1): 1144, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29074987

RESUMO

Evolution via natural selection is governed by the persistence and propagation of living things in an environment. The environment is important since it enabled life to emerge, and shapes evolution today. Although evolution has been widely studied in a variety of fields from biology to computer science, still little is known about the impact of environmental changes on an artificial chemical evolving system outside of computer simulations. Here we develop a fully automated 3D-printed chemorobotic fluidic system that is able to generate and select droplet protocells in real time while changing the surroundings where they undergo artificial evolution. The system is produced using rapid prototyping and explicitly introduces programmable environments as an experimental variable. Our results show that the environment not only acts as an active selector over the genotypes, but also enhances the capacity for individual genotypes to undergo adaptation in response to environmental pressures.

7.
Nat Commun ; 8: 15589, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28593940

RESUMO

Multi-drug strategies have been attempted to prolong the efficacy of existing antibiotics, but with limited success. Here we show that the evolution of multi-drug-resistant Escherichia coli can be manipulated in vitro by administering pairs of antibiotics and switching between them in ON/OFF manner. Using a multiplexed cell culture system, we find that switching between certain combinations of antibiotics completely suppresses the development of resistance to one of the antibiotics. Using this data, we develop a simple deterministic model, which allows us to predict the fate of multi-drug evolution in this system. Furthermore, we are able to reverse established drug resistance based on the model prediction by modulating antibiotic selection stresses. Our results support the idea that the development of antibiotic resistance may be potentially controlled via continuous switching of drugs.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Quimioterapia Combinada/métodos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Teóricos
8.
Biosystems ; 140: 28-34, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26747638

RESUMO

Understanding ecosystem dynamics is crucial as contemporary human societies face ecosystem degradation. One of the challenges that needs to be recognized is the complex hierarchical dynamics. Conventional dynamic models in ecology often represent only the population level and have yet to include the dynamics of the sub-organism level, which makes an ecosystem a complex adaptive system that shows characteristic behaviors such as resilience and regime shifts. The neglect of the sub-organism level in the conventional dynamic models would be because integrating multiple hierarchical levels makes the models unnecessarily complex unless supporting experimental data are present. Now that large amounts of molecular and ecological data are increasingly accessible in microbial experimental ecosystems, it is worthwhile to tackle the questions of their complex hierarchical dynamics. Here, we propose an approach that combines microbial experimental ecosystems and a hierarchical dynamic model named population-reaction model. We present a simple microbial experimental ecosystem as an example and show how the system can be analyzed by a population-reaction model. We also show that population-reaction models can be applied to various ecological concepts, such as predator-prey interactions, climate change, evolution, and stability of diversity. Our approach will reveal a path to the general understanding of various ecosystems and organisms.


Assuntos
Ecossistema , Consórcios Microbianos/fisiologia , Interações Microbianas/fisiologia , Modelos Biológicos , Dinâmica Populacional , Comportamento Predatório/fisiologia , Animais , Simulação por Computador
9.
PLoS One ; 10(11): e0141640, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26558389

RESUMO

Three dimensional (3D) printing is actively sought after in recent years as a promising novel technology to construct complex objects, which scope spans from nano- to over millimeter scale. Previously we utilized Fused deposition modeling (FDM)-based 3D printer to construct complex 3D chemical fluidic systems, and here we demonstrate the construction of 3D milli-fluidic structures for programmable liquid handling and control of biological samples. Basic fluidic operation devices, such as water-in-oil (W/O) droplet generators for producing compartmentalized mono-disperse droplets, sensor-integrated chamber for online monitoring of cellular growth, are presented. In addition, chemical surface treatment techniques are used to construct valve-based flow selector for liquid flow control and inter-connectable modular devices for networking fluidic parts. As such this work paves the way for complex operations, such as mixing, flow control, and monitoring of reaction / cell culture progress can be carried out by constructing both passive and active components in 3D printed structures, which designs can be shared online so that anyone with 3D printers can reproduce them by themselves.


Assuntos
Dispositivos Lab-On-A-Chip , Impressão Tridimensional , Bactérias/isolamento & purificação
10.
PLoS One ; 10(7): e0132963, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26176953

RESUMO

Lipid vesicles, in particular Giant Unilamellar Vesicles (GUVs), have been increasingly important as compartments of artificial cells to reconstruct living cell-like systems in a bottom-up fashion. Here, we report shape transformations of lipid vesicles induced by polyethylene glycol-lipid conjugate (PEG lipids). Statistical analysis of deformed vesicle shapes revealed that shapes vesicles tend to deform into depended on the concentration of the PEG lipids. When compared with theoretically simulated vesicle shapes, those shapes were found to be more energetically favorable, with lower membrane bending energies than other shapes. This result suggests that the vesicle shape transformations can be controlled by externally added membrane molecules, which can serve as a potential method to control the replications of artificial cells.


Assuntos
Lipossomas Unilamelares/química , Micelas , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Fosfatidilgliceróis/química , Polietilenoglicóis/química , Termodinâmica
11.
Philos Trans A Math Phys Eng Sci ; 373(2046)2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26078348

RESUMO

The control and prediction of complex chemical systems is a difficult problem due to the nature of the interactions, transformations and processes occurring. From self-assembly to catalysis and self-organization, complex chemical systems are often heterogeneous mixtures that at the most extreme exhibit system-level functions, such as those that could be observed in a living cell. In this paper, we outline an approach to understand and explore complex chemical systems using an automated droplet maker to control the composition, size and position of the droplets in a predefined chemical environment. By investigating the spatio-temporal dynamics of the droplets, the aim is to understand how to control system-level emergence of complex chemical behaviour and even view the system-level behaviour as a programmable entity capable of information processing. Herein, we explore how our automated droplet-maker platform could be viewed as a prototype chemical heterotic computer with some initial data and example problems that may be viewed as potential chemically embodied computations.

12.
PLoS One ; 9(7): e101820, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24991878

RESUMO

This paper describes the utilization of giant unilamellar vesicles (GUVs) as a platform for handling chemical and biochemical reagents. GUVs with diameters of 5 to 10 µm and containing chemical/biochemical reagents together with inert polymers were fused with electric pulses (electrofusion). After reagent mixing, the fused GUVs spontaneously deformed to a budding shape, separating the mixed solution into sub-volumes. We utilized a microfluidic channel and optical tweezers to select GUVs of interest, bring them into contact, and fuse them together to mix and aliquot the reaction product. We also show that, by lowering the ambient temperature close to the phase transition temperature Tm of the lipid used, daughter GUVs completely detached (fission). This process performs all the liquid-handing features used in bench-top biochemistry using the GUV, which could be advantageous for the membrane-related biochemical assays.


Assuntos
Lipídeos/química , Técnicas Analíticas Microfluídicas/métodos , Lipossomas Unilamelares/química , Membranas Artificiais , Tamanho da Partícula , Transição de Fase , Temperatura
13.
Soft Matter ; 10(32): 6038-46, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-24998870

RESUMO

We here present a method to reconstruct effective free energy landscapes (FELs) of lipid vesicles from the statistical analysis of a large number of microscope images. This method, not only allows us to define possible energy landscapes, but also highlights minority vesicle shapes that were otherwise hidden in the majority. When compared with temporal evolution of deforming lipid vesicles, it was found that the trajectory of deforming vesicles was in accordance with the reconstructed landscape, in which the minority shapes play a key role. When compared with theoretical models, it revealed that the vesicle shapes characterised in the reconstructed FELs were consistent with the theoretically predicted shapes. These results suggest that the FEL analysis can be a useful tool to investigate the morphological dynamics of lipid vesicles, in conjunction with other analytical methods.


Assuntos
Modelos Teóricos , Fosfatidilcolinas/química , Fosfatidilgliceróis/química , Interpretação Estatística de Dados , Pressão Osmótica , Análise de Componente Principal
14.
Int J Hematol ; 99(4): 457-62, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24619827

RESUMO

High-dose melphalan has been gaining recognition as a highly emetogenic agent used in hematopoietic stem cell transplantation (HSCT). The aim of this retrospective study was to elucidate the efficacy of aprepitant in preventing high-dose melphalan-induced emesis. Sixty patients who received melphalan (70 mg/m(2)/day, 2 days) and fludarabine (125 mg/m(2)/day, 5 days) as conditioning for allogeneic HSCT for hematological malignancies, and who received ondansetron and methylprednisolone as an antiemetic prophylaxis, were eligible. Twenty of these 60 patients also received aprepitant for 5 days (aprepitant group); the remaining 40 patients served as a control. The rates of complete response (CR), defined as no emesis without rescue medications, and complete protection (CP), defined as no emesis with or without rescue medications, were assessed between the two groups. The observation period was 12 days from the first day of melphalan administration. The CR and CP rates were significantly higher in the aprepitant group than in the control group during the observation period (35 % versus 10 %, P < 0.05; 85 % versus 33 %, P < 0.001; respectively). These results suggest that aprepitant in combination with ondansetron and steroid effectively ameliorates nausea and vomiting caused by the high-dose melphalan-based conditioning for allogeneic HSCT.


Assuntos
Antieméticos/uso terapêutico , Melfalan/efeitos adversos , Morfolinas/uso terapêutico , Agonistas Mieloablativos/efeitos adversos , Náusea/tratamento farmacológico , Condicionamento Pré-Transplante/efeitos adversos , Vômito/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aprepitanto , Feminino , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Agonistas Mieloablativos/administração & dosagem , Náusea/induzido quimicamente , Estudos Retrospectivos , Transplante Homólogo , Vômito/induzido quimicamente
15.
Chem Commun (Camb) ; 48(42): 5085-7, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22517276

RESUMO

We show how an array of ion-sensitive-field-effect-transistors can be used to both spatially and temporally image the oscillating pH/ion waves produced by the Belousov-Zhabotinsky (BZ) reaction with high resolution.

16.
Biosystems ; 103(3): 331-41, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21070831

RESUMO

The regeneration process of contractile oscillation in the plasmodium of Physarum polycephalum is investigated experimentally and modelled computationally. When placed in a well, the Physarum cell restructures the body (fusion of small granule-like cells) and shows various complex oscillation patterns. After it completed the restructuring and regained synchronized oscillation within the body, the cell shows bilateral oscillation or rotating wave pattern. This regeneration process did not depend on the well size and all the cases tested here showed similar time course. Phase synchronization analysis based on Hilbert Transform also suggested that the cell can develop a fully synchronized oscillation within a fixed time no matter what the cell size is. A particle-based computational model was developed in order to model the emergence of oscillation patterns. Particles employing very simple and identical sensory and motor behaviors interacted with each other via the sensing and deposition of chemoattractants in a diffusive environment. From a random and almost homogeneous distribution, emergent domains of oscillatory activity emerged. By increasing the sensory radius the model simulated the regeneration process of the real plasmodium. In addition, the model replicated the rotating wave and bilateral oscillation pattern when the sensory radius was increased. The results suggest that complex emergent oscillatory behaviors (and thus the high-level systems which may utilize them, such as pumping and transport mechanisms) may be developed from simple materials inspired by Physarum slime mold.


Assuntos
Corrente Citoplasmática , Modelos Biológicos , Physarum polycephalum/fisiologia , Fenômenos Biomecânicos , Quimiotaxia , Difusão , Oscilometria , Periodicidade , Regeneração
17.
Biosens Bioelectron ; 25(5): 1109-15, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19850464

RESUMO

Electrical impedance tomography is an imaging technology that spatially characterizes the electrical properties of an object. We present a miniaturized electrical impedance tomography system that can image the electrical conductivity distribution within a two-dimensional cell culture. A chip containing a circular 16-electrode array was fabricated using printed circuit board developing technology and used to inject current and to measure spatial voltage across the object. The signal stimulation and voltage data acquisition were performed using an impedance analyzer, operating in four-electrode mode. An open source software, EIDORS was used for image reconstruction. Finite element modelling was used to simulate the image reconstruction process by imaging two ellipsoidal phantoms in the circular 16-electrode array. The effect of the regularization parameter in the reconstruction algorithm and the influence from noise on the fidelity of the images has been numerically analyzed. Experimentally, we show reconstructed images of a multi-nuclear single cellular organism, Physarum Polycephalum, demonstrating the first step towards impedance imaging of single cells in culture. Our system provides a non-invasive lab-on-a-chip technology for spatially mapping the electrical properties of single cells, which would be significant and useful for diagnostic and clinical applications.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas de Cultura de Células/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Physarum polycephalum/fisiologia , Pletismografia de Impedância/instrumentação , Tomografia/instrumentação , Impedância Elétrica , Eletrodos , Desenho de Equipamento , Análise de Falha de Equipamento , Physarum polycephalum/citologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Biosystems ; 87(2-3): 215-23, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17188804

RESUMO

At present there exists a large gap in size, performance, adaptability and robustness between natural and artificial information processors for performing coherent perception-action tasks under real-time constraints. Even the simplest organisms have an enviable capability of coping with an unknown dynamic environment. Robots, in contrast, are still clumsy if confronted with such complexity. This paper presents a bio-hybrid architecture developed for exploring an alternate approach to the control of autonomous robots. Circuits prepared from amoeboid plasmodia of the slime mold Physarum polycephalum are interfaced with an omnidirectional hexapod robot. Sensory signals from the macro-physical environment of the robot are transduced to cellular scale and processed using the unique micro-physical features of intracellular information processing. Conversely, the response form the cellular computation is amplified to yield a macroscopic output action in the environment mediated through the robot's actuators.


Assuntos
Physarum polycephalum/fisiologia , Robótica , Animais , Modelos Biológicos , Movimento (Física) , Transdução de Sinais , Biologia de Sistemas
19.
Biosystems ; 73(1): 45-55, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14729281

RESUMO

There have been many attempts for realization of emergent computing, but the notion of emergent computing is still ambiguous. In an open system, emergence and an error cannot be specified distinctly, because they are dependent on the dis-equilibration process between local and global behaviors. To manifest such an aspect, we implement a Boolean gate as a biological device made of slime mold Physarum polycephalum. A Physarum (slime mold) Boolean gate could be an internally instable machine, while it has the potential for emergent computing. First, we examined whether Physarum Boolean gate works properly, and then examined its behaviors when the gate is collapsed in terms of hardware. The behavior of Physarum changes and self-repairing computing is achieved as a result. The self-repairing against internal failure is one of attributes of emergent and robust computing.


Assuntos
Biologia Computacional/métodos , Physarum polycephalum/fisiologia , Animais , Simulação por Computador
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