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Additive manufacturing (3D printing) technology aligns with the direction of precision and customization in future medicine, presenting a significant opportunity for innovative development in high-end medical devices. Currently, research and industrialization of 3D printed medical devices mainly focus on nondegradable implants and degradable implants. Primary areas including metallic orthopaedic implants, polyether-ether-ketone (PEEK) bone implants, and biodegradable implants have been developed for clinical and industrial application. Recent research achievements in these areas are reviewed, with a discussion on the additive manufacturing technologies and applications for customized implants. Challenges faced by different types of implants are analyzed from technological, application, and regulatory perspectives. Furthermore, prospects and suggestions for future development are outlined.
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Impresión Tridimensional , Prótesis e Implantes , Benzofenonas , Polímeros , Humanos , Cetonas , Diseño de Prótesis , Materiales Biocompatibles , Polietilenglicoles , Implantes AbsorbiblesRESUMEN
Van der Waals epitaxy (vdWE) is crucial for heteroepitaxy of covalence-bonded semiconductors on 2D layered materials because it is not subject to strict substrate requirements and the epitaxial materials can be transferred onto various substrates. However, planar film growth in covalence-bonded semiconductors remains a critical challenge of vdWE because of the extremely low surface energy of 2D materials. In this study, direct growth of wafer-scale single-crystalline cadmium telluride (CdTe) films is achieved on 2D layered transparent mica through molecular beam epitaxy. The vdWE CdTe films exhibit a flat surface resulting from the 2D growth regime, and high crystal quality as evidenced by a low full width at half maximum of 0.05° for 120 nm thick films. A perfect lattice fringe appears at the interfaces, implying a fully relaxed state of the epitaxial CdTe films correlated closely to the unique nature of vdWE. Moreover, the vdWE CdTe photodetectors demonstrate not only ultrasensitive optoelectronic response with optimal responsivity of 834 A W-1 and ultrahigh detectivity of 2.4 × 1014 Jones but also excellent mechanical flexibility and durability, indicating great potential in flexible and wearable devices.
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The luminescences of zinc-blende MnTe epitaxial films are respectively excited by a laser and deuterium lamp to study Mn2+d-d multiplets transitions. Besides the inclusion of the band gap, all other excited states related to Mn2+d-d transitions including T14(G4), T24(G4), A14[E4(G4)], T24(D4), E4(D4), and T22(I2) are observed. The shift and broadening of the T14(G4) and T24(G4) lines with increasing temperature are described by the electron-phonon coupling. Step-like energy and intensity shifts for the A14[E4(G4)], T24(D4), E4(D4), and T22(I2) transitions occur in the vicinity of the Néel point, which can be ascribed to the different spin-ordering-induced energy relaxation in ground and excited states of Mn2+d-d multiplets, and these transitions show temperature independence and weak quenching.
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Prophenoloxidase (proPO) activating system is an important immune response for arthropods. ß-1, 3-glucanase related protein (previously named as lipopolysaccharide and ß-1, 3-glucan binding protein (LGBP) in crustaceans) is a typical pattern recognition receptor family involved in the proPO activation by recognizing the invading microbes. In this study, we pay special attention to a bacteria-induced ß-1,3-glucanase related protein from red swamp crayfish Procambarus clarkii, an important aquaculture specie in China. This protein, designated PcBGRP, was found a typical member of crustacean BGRP family with the glucanase-related domain and the characteristic motifs. PcBGRP was expressed in hemcoyes and hepatopancreas, and its expression could be induced by the carbohydrate and bacteria stimulants. The induction by lipopolysaccharide (LPS) and ß-1,3-glucan (ßG) was more significant than by peptidoglycan (PG). The response of PcBGRP to the native Gram-negative bacterial pathogen Aeromonas hydrophila was more obvious than to Gram-positive bacteria. Using RNA interference and recombinant protein, PcBGRP was found to protect crayfish from A. hydrophila infection revealed by the survival test and morphological analysis. A mechanism study found PcBGRP could bind LPS and ßG in a dose-dependent manner, and the LPS recognizing ability determined the Gram-negative bacterium binding activity of PcBGRP. PcBGRP was found to enhance the PO activation both in vitro and in vivo, and the protective role was related to the PO activating ability of PcBGRP. This study emphasized the role of BGRP family in crustacean immune response, and provided new insight to the immunity of red swamp crayfish which suffered serious disease during the aquaculture in China.
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Proteínas de Artrópodos/inmunología , Astacoidea/inmunología , Proteínas Portadoras/inmunología , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones Estafilocócicas/inmunología , Aeromonas hydrophila , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos/genética , Astacoidea/genética , Proteínas Portadoras/genética , Glucano 1,3-beta-Glucosidasa/farmacología , Infecciones por Bacterias Gramnegativas/genética , Infecciones por Bacterias Gramnegativas/veterinaria , Hemocitos/inmunología , Hepatopáncreas/inmunología , Lipopolisacáridos/farmacología , Sistemas de Lectura Abierta , Peptidoglicano/farmacología , Infecciones Estafilocócicas/genética , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureusRESUMEN
Microsporidiosis is an important zoonotic disease, even leading to severe diarrhea. However, no information about prevalence and genotypes of Enterocytozoon bieneusi infection in Asiatic black bears in southwestern China is available. The objectives of the present study were to investigate the prevalence of E. bieneusi and to characterize their genotypes using the nested PCR amplification of the internal transcribed spacer region of the ribosomal RNA gene cluster and multilocus sequence typing (MLST). The overall prevalence of E. bieneusi was 19.75% (80/405) and the rate of E. bieneusi in Xishuangbanna (33.33%) was significantly higher than that in any other regions (Honghe, 17.65%; Dehong, 13.04%; Kunming, 0; P = 0.01). Sequence analysis revealed that 4 known genotypes (D, n = 2; SC02, n = 10; SC01, n = 5; and CHB1, n = 4) and 13 novel genotypes (designed MJ1-MJ13) were identified. When 17, 5, 14, and 34 sequences at loci MS1, MS3, MS4, and MS7 via MLST analyses, representing 4, 4, 5, and 10 genotypes, respectively, were completed, one multilocus genotype (MLG novel-ABB1) was identified. This is the first report of E. bieneusi in Asiatic black bear in Yunnan province, Southwestern China. The results indicated the potential zoonotic risk of this parasite through the Asiatic black bear in this region and provided foundation data for preventing and controlling E. bieneusi infection of many other animals and humans in these regions.
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Enterocytozoon/genética , Microsporidiosis/epidemiología , Ursidae/parasitología , Zoonosis/epidemiología , Animales , China/epidemiología , ADN Espaciador Ribosómico/genética , Enterocytozoon/clasificación , Enterocytozoon/aislamiento & purificación , Genotipo , Microsporidiosis/parasitología , Tipificación de Secuencias Multilocus , Filogenia , Reacción en Cadena de la Polimerasa , Prevalencia , Factores de Riesgo , Zoonosis/parasitologíaRESUMEN
Antimicrobial peptides (AMPs) are small effectors in host defense by directly targeting microorganisms or by indirectly modulating immune responses. In the present study, two arasin like AMPs, named as Pc-arasin1 and Pc-arasin2, were identified in red swamp crayfish Procambarus clarkii with sequence similarity to the arasins found in Hyas araneus. Both Pc-arasins consisted of signal peptide, N-terminal proline-rich region and C-terminal region containing four conserved cysteine residues. The similarity of two Pc-arasins was 44.44%, and Pc-arasin2 contained several additional residues in the N-terminus. Multiple alignment of arasin family suggested the conservation of the C-terminus and the variation of the N-terminus of Pc-arasins. Both AMPs were found hemocytes-specific, and the expression could be induced the challenge of bacteria, espeacially by the pathogenic bacterium Aeromonas hydrophila. Knockdown of each Pc-arasin expression by double strand RNA would suppress the host immunity against A. hydrophila, and the commercially synthetic Pc-arasins could rescue the knockdown consequence. Both synthetic peptide showed broad antimicrobial activity towards 3 Gram-positive bacterium and 3 Gram-negative bacterium, and the minimal inhibitory concentrations varied from 6.25 µM to 50 µM. These results presented new data about the sequence, expression and function of arasin family, and emphasized the role of this family in host immune response against bacterial pathogens. The characterization of Pc-arasins also provided potential of therapeutic agent development for disease control in aquaculture based on these two newly identified AMPs.
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Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/inmunología , Astacoidea/genética , Astacoidea/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos/química , Proteínas de Artrópodos/química , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Secuencia de Bases , ADN , Perfilación de la Expresión Génica , Filogenia , ARN , Alineación de SecuenciaRESUMEN
Janus kinase (Jak) and signal transducers and activators of transcription (STAT) signaling pathway is associated in antiviral and antibacterial immune response. Previous studies primarily investigated the function of STATs in mammals. For most invertebrates, only one STAT was found in each species, such as STAT92E was found in Drosophila melanogaster. The studies, which focus on the functional difference between various STATs in the same species of invertebrate, are limited. In the present study, three STATs (HcSTAT1, HcSTAT2 and HcSTAT3) were identified in triangle shell pearl mussel, Hyriopsis cumingii. Phylogenetic analysis showed that HcSTAT1 and HcSTAT3 were clustered with Homo sapiens STAT5, and HcSTAT2 was clustered with Pinctada fucata STAT and Crassostea gigas STAT6. All three STATs could be detected in all tested tissues (hemocytes, hepatopancreas, gill, mantle and foot), and were induced expression when challenged with Staphylococcus aureus or Aeromonas hydrophilia in hemocytes and hepatopancreas. HcSTAT1 regulated the expression of HcDef, HcWAP, HcThe and HcTNF. The expression of HcWAP and HcTNF was down-regulated in HcSTAT2-RNAi mussel. And HcSTAT3 affected the expression of HcTNF. The study is the first report of different functions in antibacterial immune responses between STATs in mollusks.
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Aeromonas hydrophila/fisiología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Factores de Transcripción STAT/metabolismo , Staphylococcus aureus/fisiología , Unionidae/genética , Unionidae/inmunología , Animales , Especificidad de Órganos , Filogenia , Factores de Transcripción STAT/genética , Análisis de Secuencia de ADN , Unionidae/microbiologíaRESUMEN
Based on wavelet transforms (WTs), an alternative multi-frequency fringe projection profilometry is described. Fringe patterns with multiple frequencies are projected onto an object and the reflected patterns are recorded digitally. Phase information for every pattern is calculated by identifying the ridge that appears in WT results. Distinct from the phase unwrapping process, a peak searching algorithm is applied to obtain object height from the phases of the different frequency for a single point on the object. Thus, objects with large discontinuities can be profiled. In comparing methods, the height profiles obtained from the WTs have lower noise and higher measurement accuracy. Although measuring times are similar, the proposed method offers greater reliability.
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BACKGROUND: There is a lack of understanding of the morphological characteristics of the cartilage-bone interface. Materials that are currently being used in tissue engineering do not adequately support the regeneration of bone and cartilage tissues. The present study aimed to explore the morphological characteristics of cartilage-bone transitional structures in the human knee joint and to design a biomimetic osteochondral scaffold based on morphological data. METHODS: Histology, micro-computed tomography (micro-CT), and scanning electron microscopy (SEM) were used to investigate the microstructure of the cartilage-bone transitional structures. Morphological characteristics and their distribution were obtained and summarized into a biomimetic design. A three-dimensional model of a biomimetic osteochondral scaffold was CAD designed. A prototype of the resulting subchondral bone scaffold was constructed by stereolithography using resin. RESULTS: Micro-CT revealed that subchondral bone presented a gradually changing structure from the subchondral to spongy bone tissue. The subchondral bone plate was more compact with ~20 % porosity compared with ~60 % porosity for the spongy bone. Histology and SEM showed that cartilage was stabilized on the subchondral bone plate by conjunctions, imbedding, interlocking, and binding forces generated by collagen fibers. Some scattered defects allow blood vessel invasion and nutritional supply. CONCLUSIONS: The subchondral bone plate is not an intact plate between the cartilage and bone cavity, and some scattered defects exist that allow blood vessel invasion and nutritional supply. This characteristic was used to design an osteochondral scaffold. This could be used to construct an osteochondral complex that is similar to native bones.
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Materiales Biomiméticos , Huesos/citología , Cartílago Articular/citología , Diseño Asistido por Computadora , Articulación de la Rodilla/citología , Andamios del Tejido , Adulto , Huesos/diagnóstico por imagen , Cartílago Articular/diagnóstico por imagen , Femenino , Humanos , Imagenología Tridimensional , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Microtomografía por Rayos XRESUMEN
We propose a novel multi-frequency color-marked fringe projection profilometry approach to measure the 3D shape of objects with depth discontinuities. A digital micromirror device projector is used to project a color map consisting of a series of different-frequency color-marked fringe patterns onto the target object. We use a chromaticity curve to calculate the color change caused by the height of the object. The related algorithm to measure the height is also described in this paper. To improve the measurement accuracy, a chromaticity curve correction method is presented. This correction method greatly reduces the influence of color fluctuations and measurement error on the chromaticity curve and the calculation of the object height. The simulation and experimental results validate the utility of our method. Our method avoids the conventional phase shifting and unwrapping process, as well as the independent calculation of the object height required by existing techniques. Thus, it can be used to measure complex and dynamic objects with depth discontinuities. These advantages are particularly promising for industrial applications.
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All cases with total anomalous pulmonary venous connection (TAPVC) were reported in neonates and children in the previous literature. This report describes the only case in which a mixed supra- and intracardiac TAPVC was discovered in a 25-year-old adult female and multidetector-row computed tomography (MDCT) angiography was used in its pre- and postoperative evaluation. Multidetector-row computed tomography angiography is superior to echocardiography in showing the draining sites and courses of the anomalous connected pulmonary veins, as well as postoperative evaluation in a patient with mixed TAPVC. It indicates that MDCT angiography may be a more suitable diagnostic modality for use in the pre- and postoperative evaluation of the mixed TAPVC.
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Angiografía , Tomografía Computarizada Multidetector , Síndrome de Cimitarra , Adulto , Femenino , Humanos , Síndrome de Cimitarra/diagnóstico por imagen , Síndrome de Cimitarra/fisiopatología , Síndrome de Cimitarra/cirugíaRESUMEN
Focusing on the poor mechanical strength of porous bioceramics bone scaffold, and taking into account of the good mechanical properties of biodegradable magnesium alloy, we proposed a novel method to fabricate magnesium alloy/bioceramics composite bone scaffold with stereolithography double channels. Firstly, a scaffold structure without mutually connected double channels was designed. Then, an optimized bioceramics scaffold was fabricated according to stereolithography and gel-casing. Molten AZ31 magnesium alloy was perfused into the secondary channel of scaffold by low-pressure casting, and magnesium alloy/bioceramics composite bone scaffold was obtained when magnesium alloy was solidified. The compression test showed that the strength of bioceramics scaffold with only one channel and without magnesium alloy was (9.76 ± 0.64) MPa, while the strength of magnesium alloy/bioceramics composite scaffold with double channels was (17.25 ± 0.88) MPa. It can be concluded that the magnesium alloy/bioceramics composite is obviously able to improve the scaffold strength.
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Huesos , Cerámica , Ensayo de Materiales , Andamios del Tejido , Aleaciones , Fenómenos Biomecánicos , Humanos , Magnesio , PorosidadRESUMEN
Elevated evidence has reported the important role of oxidative stress injury and inflammatory response in the progression of colitis. Tumor Suppressor TSBF1, TRIM59, is a ubiquitin E3 ligase and mediates immune response. However, the underlying molecular function of TRIM59 on regulation of colitis is still not understood. In the current study, we identify the TRIM59 as a critical and novel endogenous suppressor of kelch-like ECH-associated protein 1 (KEAP1), and we also determine that TRIM59 is a KEAP1-interacting partner protein that catalyses its ubiquitination and degradation in intestinal epithelial cells (IEC). Moreover, IEC-specific loss of the Trim59 disrupts colon metabolic homeostasis, accompanied by intestinal oxidative stress injury, elevated endogenous reactive oxygen species (ROS) production and pro-inflammatory cytokines release, significantly promotes acute or chronic colitis progression. Conversely, transgenic mice with Trim59 overexpression by adeno-associated virus (AAV)-induced Trim59 gene therapeutics mitigates colitis in acute or chronic colitis rodent models and in vitro experiments. Mechanistically, in response to onset of colitis, TRIM59 directly interacts with KEAP1 and promotes ubiquitin-proteasome degradation, thus results in NRF2 activation and its downstream cascade anti-oxidative stress-related pathway activation, which facilitates anti-oxidant defense and reduces tissue damage. All the findings elucidated the potential role of TRIM59 in colitis progression by mediating KEAP1 deactivation and degradation, and could be considered as a therapeutic target for the treatment of such disease.
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Colitis , Factor 2 Relacionado con NF-E2 , Animales , Ratones , Enfermedad Crónica , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Ratones Transgénicos , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Transducción de Señal , Ubiquitina/metabolismo , Ubiquitina/farmacologíaRESUMEN
The antibacterial and antiviral functions of human defensin 5 lay the foundation for its role as a core host protective component. In addition, HD5 also has the function of inhibiting tumor proliferation and immune regulation. However, everything has two sides; cytotoxic and proinflammatory properties may exist, while HD5 performs physiological functions. Accordingly, the modification and engineering of HD5 are particularly important. Therefore, this review summarizes the role of HD5 in various aspects of host defense, as well as modification of HD5 to ameliorate the biological activity, with a view to promoting the clinical use of HD5.
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alfa-Defensinas , Humanos , alfa-Defensinas/química , alfa-Defensinas/metabolismo , alfa-Defensinas/farmacología , AntibacterianosRESUMEN
This study aimed to investigate the effects of selenium (Se)-enriched Bacillus subtilis (Se-BS) on growth performance, antioxidant capacity, immune status, and gut health in broilers. A total of 240 one-day-old Arbor Acres broilers were randomly allotted to four groups and fed with basal diet (control group), 0.30 mg/kg Se (SS group), 3 × 109 CFU/g B. subtilis (BS group), and 0.30 mg/kg Se + 3 × 109 CFU/g B. subtilis (Se-BS group) for 42 days. The results showed that Se-BS supplementation increased body weight (BW), average daily gain, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and peroxidase (POD), total antioxidant capacity (T-AOC), and the contents of interleukin (IL)-2, IL-4, and immunoglobulin (Ig) G in plasma, the index and wall thickness of the duodenum, the villus height and crypt depth of the jejunum, and GPx-1 and thioredoxin reductase 1 mRNA levels in liver and intestine and decreased feed conversion ratio (FCR) and plasma malondialdehyde (MDA) content compared with the control group on day 42 (P < 0.05). Compared with groups SS and BS, Se-BS supplementation increased BW, the activities of GPx, CAT, and POD, and the contents of IL-2, IL-4, and IgG in plasma, the index and wall thickness of the duodenum, the crypt depth and secretory IgA content of the jejunum, and GPx-1 mRNA levels in liver and intestine and decreased FCR and plasma MDA content on day 42 (P < 0.05). In conclusion, Se-BS supplementation effectively improved the growth performance antioxidant capacity, immune status, and gut health of broilers.
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Antioxidantes , Selenio , Animales , Selenio/farmacología , Pollos , Bacillus subtilis , Suplementos Dietéticos , Interleucina-4 , Dieta/veterinaria , Glutatión Peroxidasa , ARN Mensajero/genética , Alimentación Animal/análisisRESUMEN
In-situ three-dimensional (3D) bioprinting has been emerging as a promising technology designed to rapidly seal cutaneous defects according to their contour. Improvements in the formulations of multi-component bioink are needed to support cytocompatible encapsulation and biological functions. Platelet-rich plasma (PRP), as a source of patient-specific autologous growth factors, exhibits capabilities in tissue repair and rejuvenation. This study aimed to prepare PRP-integrated alginate-gelatin (AG) composite hydrogel bioinks and evaluate the biological effects in vitro and in vivo. 3D bioprinted constructs embedded with dermal fibroblasts and epidermal stem cells were fabricated using extrusion strategy. The integration of PRP not only improved the cellular behavior of seeded cells, but regulate the tube formation of vascular endothelial cells and macrophage polarization in a paracrine manner, which obtained an optimal effect at an incorporation concentration of 5%. For in-situ bioprinting, PRP integration accelerated the high-quality wound closure, modulated the inflammation and initiated the angiogenesis compared with the AG bioink. In conclusion, we revealed the regenerative potential of PRP, readily available at the bedside, as an initial signaling provider in multi-component bioink development. Combined with in-situ printing technology, it is expected to accelerate the clinical translation of rapid individualized wound repair.
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The 18 biochemical parameters of serum were measured to analyze the pathogenic risks of the Yangtze River Source of Drinking Water in Nanjing area (YZR-SDW-NJ) on mouse Mus musculus for protection of human health in this research. The male mice Mus musculus were sampled and fed with YZR-SDW-NJ for 90 days then the eighteen serum biochemical levels were measured with Automatic Biochemical Analysis/RerLi 600. And the parameter data were treated by One-Way ANOVA statistic approach. The results showed that five parameter levels for the sample group mice were different from those for the control group significantly (0.01 < P or 0.05 < P). Four 4 of the 5 altered parameter levels were decreased including glutamate pyruvate transaminase 38% lower, glutamine-oxaloacetic transaminase 24% lower, triglyceride 76% lower and cystatin C 73% lower, only creatinine level was 26% higher than that in the control group. The data suggest that YZR-SDW-NJ had toxicity on the mouse and the organic pollutants in YZR-SDW-NJ might lead to liver, kidney, cardiovascular and metabolic pathogenic risks on the human beings. The results might be cited as evidence to control pollutants in the source water for the protection of NJ people's health.
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Contaminantes Químicos del Agua/toxicidad , Abastecimiento de Agua/análisis , Alanina Transaminasa/metabolismo , Animales , China , Ciudades , Monitoreo del Ambiente/métodos , Agua Dulce/química , Masculino , Ratones , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/estadística & datos numéricosRESUMEN
Referring to the anatomical characterization of natural spongy bone and channel network in cortical bone, we designed a new pattern of biomimetic impalnt with preset channel for blood vessel inserting to treat early femoral head necrosis. The surgical ptrocedure was simulated by CAD model. Ceramic stereolithography was applied to fabricate the green part. Other process, such as dehydration, rinsing, drying and sintering, were taken successively. The final ceramic part kept identical with the engineered part either in the shape or in the internal structure. No deformation or crack happened. Pore size, interconnected pore size, porosity and interconnected porosity of ceramic part could satisfy cellular grouth. Spectrum analysis showed that no phase transition or chemical reaction happened during fabrication process. The biocompatibility of the final part kept the same with original during beta-TCP powder. The compressive strength was 23.54 MPa, close to natural spongy bone. It is an ideal implant to treat early femoral head necroseis because it makes preimplantation of cells and biological factors, blood velssel inserting, early establishment of blood supply possible. At the same time, it could provide enough mechanical support to prevent collapse of femoral head. It could provide a wide clinical foreground.
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Fosfatos de Calcio/química , Diseño Asistido por Computadora , Necrosis de la Cabeza Femoral/terapia , Ingeniería de Tejidos , Andamios del Tejido/química , Materiales Biocompatibles/química , Sustitutos de Huesos/síntesis química , Sustitutos de Huesos/química , Humanos , Porosidad , Prótesis e ImplantesRESUMEN
Living cells are highly scalable biological actuators found in nature, and they are efficient technological solutions to actuate robotic systems. Recent advancements in biofabrication and tissue engineering have bridged the gap to interface muscle cells with artificial technology. In this review, we summarize the recent progress in engineering the attributes of individual components for the development of fully functional biohybrid robots. First, we address the fabrication of biological actuators for biohybrid robots with muscle cells and tissues, including cardiomyocytes, skeletal muscles, insect tissues, and neuromuscular tissues, in well-organized pattern of 2D sheets and 3D constructs. Next, we discuss the performance of biohybrid robots for various biomimetic tasks such as swimming, walking, gripping, and pumping. Finally, the challenges and future directions in the development of biohybrid robots are described from different viewpoints of living material engineering, multiscale modeling, 3D printing for manufacturing, and multifunctional robotic system development.
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Robótica , Biomimética , Músculo Esquelético , Impresión Tridimensional , Ingeniería de TejidosRESUMEN
BACKGROUND: Acute arterial occlusive mesenteric ischemia with transmural intestinal necrosis (TIN) is a fatal disease, which is difficult to diagnose on multidetector computed tomography (MDCT). The aim of the present study was to determine the relationship of superior mesenteric artery (SMA) thrombus density with TIN on MDCT in patients with acute mesenteric ischemia (AMI) due to SMA thromboembolism. METHODS: In this retrospective study, 33 patients who underwent abdominal MDCT and angiography for AMI due to SMA thromboembolism were divided into two groups: the AMI with TIN group and the AMI without TIN group. We analyzed the relationships of clinical characteristics, qualitative MDCT signs, and SMA thrombus density with TIN. The SMA thrombus density was measured on non-contrast MDCT. Univariate and multivariate analyses were performed to determine the risk factors for predicting TIN. The diagnostic performances of risk factors were evaluated by receiver-operating characteristic (ROC) curve analysis. RESULTS: Of the patients with AMI enrolled in this study, 33.3% (11/33) were diagnosed with TIN. Peritonitis (P=0.042), bowel wall thinning (P=0.033), and pneumatosis/portomesenteric gas (P=0.010) were significantly associated with TIN. AMI patients with TIN exhibited a higher SMA thrombus density than AMI patients without TIN [41.2±6.1 vs. 34.2±3.0 Hounsfield unit (HU), P=0.003]. Multivariate analysis showed that SMA thrombus density was an independent predictor of TIN [P=0.044, hazard ratio (HR): 1.82, 95% confidence interval (CI): 1.02-3.25]. For diagnosing AMI with TIN, the area under the ROC curve (AUC) of SMA thrombus density (0.83) was larger than those of peritonitis (0.68), bowel wall thinning (0.66), and pneumatosis/portomesenteric gas (0.71). CONCLUSIONS: In patients with AMI, erythrocyte-rich thrombus blocking the SMA trunk which has a higher density on MDCT is prone to the occurrence of TIN compared with erythrocyte-scarce thrombus with a lower density. SMA thrombus density could be an independent risk factor for TIN in patients with AMI due to SMA thromboembolism.