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Sinus venosus atrial septal defects (SVASDs), concurrent with partial anomalous pulmonary venous connections (PAPVCs), are a rare congenital heart disease in dogs. Surgical correction is essential when clinical signs or significant hemodynamic changes are present. We aimed to report on the successful surgical correction of an SVASD with PAPVCs, using a computed tomography (CT)-based customized 3D cardiac model. A 10-month-old male poodle was referred for corrective surgery for an ASD. Echocardiography confirmed a hemodynamically significant left-to-right shunting flow through an interatrial septal defect and severe right-sided heart volume overload. For a comprehensive diagnosis, a CT scan was performed, which confirmed an SVASD with PAPVCs. A customized 3D cardiac model was used for preoperative decision-making and surgical rehearsal. The defect was repaired using an autologous pericardial patch under a cardiopulmonary bypass (CPB). Temporary pacing was applied for sinus bradycardia and third-degree atrioventricular block. The patient recovered from the anesthesia without further complications. The pacemaker was removed during hospitalization and the patient was discharged without complications 2 weeks post-surgery. At the three-month follow-up, there was no shunting flow in the interatrial septum and the right-sided volume overload had been resolved. The cardiac medications were discontinued, and there were no complications. This report indicates the validity of surgical correction under CPB for an SVASD with PAPVCs, and the advantages of utilizing a CT-based 3D cardiac model for preoperative planning to increase the surgical success rate.
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To advance cancer treatment, we have developed a novel composite material consisting of conjugated polymer dots (CPDs) and Prussian blue (PB) particles, which were immobilized on, and encapsulated within, silica particles, respectively. The CPDs functioned as both a photosensitizer and a photodynamic agent, and the PB acted as a photothermal agent. The silica platform provided a biocompatible matrix that brought the two components into close proximity. Under laser irradiation, the fluorescence from the CPDs in the composite material enabled cell imaging and was subsequently converted to thermal energy by PB. This efficient energy transfer was accomplished because of the spectral overlap between the emission of donor CPDs and the absorbance of acceptor PB. The increase in local temperature in the cells resulted in a significant increase in the amount of reactive oxygen species (ROS) generated by CPDs, in which their independent use did not produce sufficient ROS for cancer cell treatment. To assess the impact of the enhanced ROS generation by the composite material, we conducted experiments using cancer cells under 532 nm laser irradiation. The results showed that with the increase in local temperature, the generated ROS increased by 30% compared with the control, which did not contain PB. When the silica-based composite material was positioned at the periphery of the tumor for 120 h, it led to a much slower tumor growth than other materials tested. By using a CPD-based photodynamic therapy platform, a new simplified approach to designing and preparing cancer treatments could be achieved, which included photothermal PB-assisted enhanced ROS generation using a single laser. This advancement opens up an exciting new opportunity for effective cancer treatment.
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Neoplasias , Fotoquimioterapia , Humanos , Especies Reactivas de Oxígeno , Neoplasias/tratamiento farmacológico , Polímeros/farmacología , Dióxido de SilicioRESUMEN
Cor triatriatum dexter (CTD) is an uncommon congenital cardiac anomaly in dogs. This case report describes successful membranectomy for CTD via partial venous inflow occlusion under mild hypothermia in a dog. A 7-month-old intact male mixed-breed dog weighing 20.5 kg presented with a history of abdominal distention, lethargy, and anorexia. Clinical examination, radiography, echocardiography, microbubble testing, and computed tomography revealed a remnant right atrium membrane obscuring the venous blood inflow from the vena cava. Considering the potential risk of re-stenosis following interventional treatment, curative resection involving surgical membranectomy via venous inflow occlusion was performed. By performing partial venous inflow occlusion under mild hypothermia (34.5 °C), sufficient time was obtained to explore the defect and resect the remnant membrane. The dog recovered without any complications, and the clinical signs were relieved. This case illustrates that partial venous inflow occlusion under mild hypothermia is feasible for achieving curative resection of cor triatriatum dexter in dogs.
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Del-Nido cardioplegia (DNc) is a single-dose cardioplegia that is widely used in human medicine because of its long duration. In this report, we describe two cases of open-heart surgery with cardiopulmonary bypass (CPB) using DNc. One dog was diagnosed with partial atrioventricular septal defect, and the other dog was diagnosed with myxomatous mitral valve disease stage D. Both dogs were treated with open-heart surgery with DNc to induce temporary cardiac arrest. No complications from DNc were observed, and the patients were discharged. Veterinary heart surgeons should consider DNc as an option for temporary cardiac arrest during open-heart surgery with CPB.
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Procedimientos Quirúrgicos Cardíacos , Enfermedades de los Perros , Paro Cardíaco , Humanos , Perros , Animales , Soluciones Cardiopléjicas , Paro Cardíaco Inducido/veterinaria , Procedimientos Quirúrgicos Cardíacos/veterinaria , Paro Cardíaco/veterinaria , Estudios Retrospectivos , Enfermedades de los Perros/cirugíaRESUMEN
Surgical ligation of a patent ductus arteriosus is regarded as a standard treatment approach with a low complication rate if performed by experienced surgeons, and it has been performed successfully for decades in dogs. However, there are no reports describing the clinical symptoms related to granulomatous inflammation after the surgical ligation of the patent ductus arteriosus. This report describes the clinical symptoms caused by granulomatous inflammation and subacute pericarditis in a dog that had undergone the surgical closure of a patent ductus arteriosus 2 years previously. Exploratory thoracotomy was performed for subtotal pericardiectomy, and a biopsy was performed to obtain specimens for histopathological examination and culture tests. The clinical symptoms were relieved after surgery. The persistent leukocytosis improved with steroid administration. This case illustrates that the granulomatous inflammatory response associated with silk suture granuloma is a rare postoperative complication of ductal ligation. In such cases, pericardiectomy can help relieve the clinical symptoms.
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Mitral regurgitation (MR) is the most common heart disease in small-breed dogs. Mitral repair, which comprise artificial chorda tendineae implantation and mitral annuloplasty, has become the mainstay of treatment in the veterinary field. We report on two small dogs who underwent mitral repair surgery for MR. A Hegar dilator was used during mitral annuloplasty for accurate and reproducible surgery. In both cases, mitral regurgitant flow almost disappeared after surgery, and clinical signs improved. The treatment regimen was terminated 3 months after the surgery. We concluded that using a Hegar dilator may facilitate mitral valve repair surgery.
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Enfermedades de los Perros , Anuloplastia de la Válvula Mitral , Insuficiencia de la Válvula Mitral , Animales , Enfermedades de los Perros/cirugía , Perros , Anuloplastia de la Válvula Mitral/veterinaria , Insuficiencia de la Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/veterinaria , Resultado del TratamientoRESUMEN
An 11-year-old spayed female Toy Poodle presented with acute tetraparesis. A small subcutaneous mass was found in the right trunk region, and the magnetic resonance revealed a compressive spinal cord lesion due to an irregular bone proliferation at the third cervical vertebra. After surgical resection of the vertebral lesion, the neurological symptoms improved, and the patient could walk on her own. The excised vertebral and subcutaneous masses were diagnosed as a mammary adenocarcinoma on the histopathological examination, with Ki-67 and HER-2 immunohistochemistry staining. This case report highlights the importance of defining the primary tumours of metastatic vertebral tumours and the necessity of palliative surgery to improve the patient's quality of life.
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Formic acid (HCOOH, FA) has long been considered as a promising hydrogen-storage material due to its efficient hydrogen release under mild conditions. In this work, FA decomposes to generate CO2 and H2 selectively in the presence of aqueous Pd2+ complex solutions at 333â K. Pd(NO3 )2 was the most effective in generating H2 among various Pd2+ complexes explored. Pd2+ complexes were inâ situ reduced to Pd0 species by the mixture of FA and sodium formate (SF) during the course of the reaction. Since C-H activation reaction of Pd2+ -bound formate is occurred for both Pd2+ reduction and H2 /CO2 gas generation, FA decomposition pathways using several Pd2+ species were explored using density functional theory (DFT) calculations. Rotation of formate bound to Pd2+ , ß-hydride elimination, and subsequent CO2 and H2 elimination by formic acid were examined, providing different energies for rate determining step depending on the ligand electronics and geometries coordinated to the Pd2+ complexes. Finally, Pd2+ reduction toward Pd0 pathways were explored computationally either by generated H2 or reductive elimination of CO2 and H2 gas.
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The present study was conducted for developing a new method to reduce the tannins content of Xuan Mugua fruits. Lactic acid bacteria fermentation-like incubation was explored as an efficient method to reduce the astringency of Mugua fruits by reducing tannins content. To ensure the efficient removal of tannins, the fermentation conditions were optimized such as temperature, time, and ratio of bacteria to Mugua. Bacteria were able to reduce 78% of the tannins content in Mugua under the optimized conditions as assessed by the methylcellulose perceptible tannins assay. Meanwhile, the active components including polysaccharides, triterpenes, and antioxidants of Mugua with bacterial incubation were also explored, which showed the significant decrease compared to non-fermented Mugua. However, the trend for flavor components was different. This research provides a natural method to solve the astringency problem of these fruits and it will extend their application in food industry.
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Frutas/metabolismo , Lactobacillales/metabolismo , Rosaceae/metabolismo , Taninos/metabolismo , Antioxidantes/análisis , Astringentes/metabolismo , Fermentación , Industria de Procesamiento de Alimentos/métodos , Metilcelulosa/metabolismo , Gusto , Temperatura , Triterpenos/análisis , Triterpenos/metabolismoRESUMEN
Bisphenol A (BPA) is an environmental toxin widely used in manufacturing industries. Studies conducted on the neurotoxicity of BPA demonstrated that at excessive, high concentrations (≥ 200 µM) adverse responses occurred which were not detectable using traditional toxicity tests at lower chemical quantities than 200 µM. Thus, a method capable of effectively detecting neurotoxicity at low concentrations (≤ 100 µM) was devised. Bisphenol A-mediated neurotoxicity was examined in primary cultured neurons using various methods, including Western blot, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity and reactive oxygen species assays. These methods confirmed BPA-induced toxicity at 200 µM, but no marked effect was observed at concentrations below 200 µM. However, when immunocytochemistry (ICC) was performed using a co-immunofluorescence assay of doublecortin (DCX) and microtubule-associated protein 2 (MAP2), BPA adversely affected neuronal maturation in neural progenitor cells at concentrations as low as 100 µM, at which the three traditional methods failed to detect any neurotoxic effect. Our DCX/MAP2 ICC findings indicate that low concentrations of BPA are toxic to developing neurons, and suggest that the devised double ICC technique might provide an effective means of assessing neurotoxic effects of environmental toxins at low concentrations.
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Compuestos de Bencidrilo/toxicidad , Contaminantes Ambientales/toxicidad , Neuronas/efectos de los fármacos , Síndromes de Neurotoxicidad/etiología , Fenoles/toxicidad , Animales , Encéfalo/efectos de los fármacos , Encéfalo/embriología , Muerte Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Proteína Doblecortina , Proyección Neuronal/efectos de los fármacos , Neuronas/patología , Síndromes de Neurotoxicidad/metabolismo , Síndromes de Neurotoxicidad/patología , Cultivo Primario de Células , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismoRESUMEN
OBJECTIVE: The usefulness of optic nerve sheath diameter (ONSD) in predicting increased intracranial pressure (ICP) is not well established in adults with hydrocephalus. In this retrospective study, we evaluated the correlation between ONSD measured on brain computed tomography (CT) and ICP in adults with hydrocephalus. PATIENTS AND METHODS: ONSDs were measured on preoperative brain CT images from 64 adult patients with hydrocephalus who underwent extracranial ventricular drainage or a ventriculoperitoneal shunt in 2016. ICP was defined as ventricular fluid pressure. RESULTS: The ONSD measured on preoperative CT was greater in patients (nâ¯=â¯8) with a higher ICP (>20â¯mmHg, 5.8vs. 4.9â¯mm, Pâ¯=â¯0.001). The ONSD was linearly correlated with ICP (râ¯=â¯0.543, Pâ¯<â¯0.001) and was predictive of increased ICP with an area under the receiver operating characteristic curve of 0.834. The optimal cut-off value of 5.3â¯mm ONSD yielded 88% sensitivity and 79% specificity. The inter-class coefficient of ONSD on preoperative CT was 0.882. The correlation between ONSD on preoperative CT and ICP was detected only in patients with communicating and non-communicating hydrocephalus (râ¯=â¯0.437 and râ¯=â¯0.585, Pâ¯=â¯0.037 and Pâ¯=â¯0.002, respectively). CONCLUSION: ONSD measured on preoperative brain CT was linearly correlated with ICP in adult patients with communicating and non-communicating hydrocephalus, and it was a predictor of increased ICP with good discrimination and high inter-observer reliability. These results suggest that preoperative ONSD measurement on brain CT can be helpful to safely manage such patients by providing information about ICP.
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Hidrocefalia/cirugía , Hipertensión Intracraneal/patología , Presión Intracraneal/fisiología , Nervio Óptico/patología , Tomografía Computarizada por Rayos X , Adulto , Anciano , Encéfalo/cirugía , Femenino , Humanos , Hipertensión Intracraneal/fisiopatología , Masculino , Persona de Mediana Edad , Neuroimagen/métodos , Nervio Óptico/fisiopatología , Curva ROC , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X/métodosRESUMEN
The core functions of stem cells (SCs) are critically regulated by their cellular redox status. Glutathione is the most abundant non-protein thiol functioning as an antioxidant and a redox regulator. However, an investigation into the relationship between glutathione-mediated redox capacity and SC activities is hindered by lack of probe. Here, we demonstrate that cyanoacrylamide-based coumarin derivatives are ratiometric probes suitable for the real-time monitoring of glutathione levels in living SCs. These probes revealed that glutathione levels are heterogeneous among subcellular organelles and among individual cells and show dynamic changes and heterogeneity in repopulating SCs depending on oxidative stress or culture conditions. Importantly, a subpopulation of SCs with high glutathione levels exhibited increased stemness and migration activities in vitro and showed improved therapeutic efficiency in treating asthma. Our results indicate that high glutathione levels are required for maintaining SC functions, and monitoring glutathione dynamics and heterogeneity can advance our understanding of the cellular responses to oxidative stress.
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Antioxidantes/metabolismo , Glutatión/metabolismo , Mitocondrias/metabolismo , Células Madre/metabolismo , Citosol/metabolismo , Glutatión/aislamiento & purificación , Proteínas Fluorescentes Verdes/genética , Humanos , Oxidación-Reducción , Estrés Oxidativo/genética , Especies Reactivas de OxígenoRESUMEN
UV irradiation elicits acute inflammation in the skin by increasing proinflammatory cytokine production in keratinocytes. However, the downstream protein target(s) that link UV radiation to the activation of signaling pathways responsible for cytokine expression have not been fully elucidated. In this study, we report a novel role of transglutaminase 2 (TG2), a member of the TG enzyme family whose activities are critical for cornified envelope formation, in mediating UV-induced inflammation. Our results showed that TG2-deficient mice exhibited reduced inflammatory responses to UV irradiation, including reduced erythema, edema, dilation of blood vessels, inflammatory cell infiltration, and levels of inflammatory cytokines. Using primary mouse keratinocytes and HaCaT cells, we found that UV irradiation-induced cytokine production by activating TG2, but not by upregulating TG2 expression, and that ER calcium release triggered by the UV-induced activation of phospholipase C was required for TG2 activation. Moreover, TG2 activity enhanced p65 phosphorylation, leading to an increase in NF-κB transcriptional activity. These results indicate that TG2 is a critical mediator of cytokine expression in the UV-induced inflammatory response of keratinocytes, and suggest that TG2 inhibition might be useful for preventing UV-related skin disorders, such as photoaging and skin cancer caused by chronic UV exposure.
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Citocinas/biosíntesis , Proteínas de Unión al GTP/metabolismo , Enfermedades de la Piel/enzimología , Piel/enzimología , Piel/efectos de la radiación , Transglutaminasas/metabolismo , Animales , Apoptosis/fisiología , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Ratones Noqueados , Proteína Glutamina Gamma Glutamiltransferasa 2 , Transducción de Señal , Piel/metabolismo , Enfermedades de la Piel/etiología , Enfermedades de la Piel/metabolismo , Rayos UltravioletaRESUMEN
BACKGROUND: We evaluated the posterior tibial artery as an alternative arterial cannulation site to the radial artery in small children. METHODS: A two-stage study was conducted. First, we evaluated the anatomical characteristics of the posterior tibial artery compared with the radial and dorsalis pedis arteries. Next, a parallel-arm single-blind randomized controlled study compared the initial success rate of ultrasound-guided arterial cannulation among three arteries as a primary outcome. RESULTS: Sixty patients were analyzed in the observational study. The diameter of the posterior tibial artery (1.5 ± 0.2 mm) was similar to that of the radial artery (1.5 ± 0.2 mm) and larger than that of the dorsalis pedis artery (1.2 ± 0.2 mm; P < 0.001). The posterior tibial artery has a larger cross-sectional area (2.8 ± 1.1 mm) compared with the radial (2.3 ± 0.8 mm; P = 0.013) and dorsalis pedis arteries (1.9 ± 0.6 mm; P = 0.001). In total, 234 patients were analyzed in the randomized study. The first-attempt success rate of the posterior tibial artery (75%) was similar to that of the radial (83%; P = 0.129; odds ratio, 1.53; 95% CI, 0.69 to 3.37) and higher than that of the dorsalis pedis artery (45%; P < 0.001; odds ratio, 3.95; 95% CI, 1.99 to 7.87). Median cannulation time of the posterior tibial artery (21 s; interquartile range, 14 to 30) was similar to that of the radial artery (27 s; interquartile range, 17 to 37) and shorter than that of the dorsalis pedis artery (34 s; interquartile range, 21 to 50). CONCLUSIONS: The posterior tibial artery is a reasonable alternative to the radial artery for ultrasound-guided arterial cannulation in small children.
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Cateterismo Periférico/métodos , Arteria Radial/anatomía & histología , Arteria Radial/diagnóstico por imagen , Arterias Tibiales/anatomía & histología , Arterias Tibiales/diagnóstico por imagen , Ultrasonografía Intervencional , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos , Método Simple CiegoRESUMEN
The study aimed at discriminating washed specialty Bourbon coffee from major coffee growing areas in Rwanda and evaluating the feasibility of using flavor to predict the geographical origin of Arabica coffees from different origins. Discrimination was achieved by performing a principal component analysis, and a discriminant factorial analysis (DFA) model was used to predict the geographical origin of coffee samples based on their intrinsic flavor. Discrimination results from both e-nose and e-tongue indicated clear grouping of coffee samples from areas within the same geographical sub-regions. A DFA model using e-nose was successful in predicting the geographical origin of coffee samples but not with e-tongue. Therefore, the study demonstrated that aroma could reliably be used to predict the geographical origin of coffee samples from different origins than their taste profile.
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We present a hybrid architecture, inspired by asynchronous BVH construction [1], for ray tracing animated scenes. Our hybrid architecture utilizes heterogeneous hardware resources: dedicated ray-tracing hardware for BVH updates and ray traversal and a CPU for BVH reconstruction. We also present a traversal scheme using a primitive's axis-aligned bounding box (PrimAABB). This scheme reduces ray-primitive intersection tests by reusing existing BVH traversal units and the primAABB data for tree updates; it enables the use of shallow trees to reduce tree build times, tree sizes, and bus bandwidth requirements. Furthermore, we present a cache scheme that exploits consecutive memory access by reusing data in an L1 cache block. We perform cycle-accurate simulations to verify our architecture, and the simulation results indicate that the proposed architecture can achieve real-time Whitted ray tracing animated scenes at 1,920 × 1,200 resolution. This result comes from our high-performance hardware architecture and minimized resource requirements for tree updates.
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The biopolymer chitosan has been investigated as a potential binder for the fabrication of LiFePO4 cathode electrodes in lithium ion batteries. Chitosan is compared to the conventional binder, polyvinylidene fluoride (PVDF). Dispersion of the active material, LiFePO4, and conductive agent, Super P carbon black, is tested using a viscosity analysis. The enhanced structural and morphological properties of chitosan are compared to the PVDF binder using X-ray diffraction analysis (XRD) and field emission scanning electron microscopy (FE-SEM). Using an electrochemical impedance spectroscopy (EIS) analysis, the LiFePO4 electrode with the chitosan binder is observed to have a high ionic conductivity and a smaller increase in charge transfer resistance based on time compared to the LiFePO4 electrode with the PVDF binder. The electrode with the chitosan binder also attains a higher discharge capacity of 159.4 mAh g(-1) with an excellent capacity retention ratio of 98.38% compared to the electrode with the PVDF binder, which had a discharge capacity of 127.9 mAh g(-1) and a capacity retention ratio of 85.13%. Further, the cycling behavior of the chitosan-based electrode is supported by scrutinizing its charge-discharge behavior at specified intervals and by a plot of dQ/dV.
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Biopolímeros/química , Quitosano/química , Suministros de Energía Eléctrica , Electrodos , Tecnología Química Verde/métodos , Litio/química , Conductividad Eléctrica , Transferencia de Energía , Diseño de Equipo , Análisis de Falla de Equipo , Iones , Ensayo de Materiales , Polivinilos/químicaRESUMEN
Lithium-ion batteries with vinylene carbonate (VC) in the electrolyte exhibit superior electrochemical and thermal behavior at elevated temperature, especially with a high Ni content in the cathode material. When VC is added to the electrolyte, polymeric species are formed on the cathode surface by a ring-opening reaction of ethylene carbonate (EC) in the electrolyte and VC, respectively. Through X-ray photoelectron spectroscopy (XPS) depth profiling, we have confirmed that these polymer layers are porous and complementary to each other. XPS results of C1s and O1s show that the outer surface and the inner layer consist of different components. Based on the XPS depth profiling results, we have suggested a reaction mechanism for the formation of a thermally stable layer on the cathode when vinylene carbonate is added to the electrolyte.
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Screening of zearalenone (ZEN)-producing species and monitoring of ZEN in feed were performed by using anti-zearalenone monoclonal antibodies. ELISA recoveries of ZEN from corn distillers dried grains with solubles (DDGS) feed, corn feed, rice bran, soybean meal, wheat bran and rapeseed dregs were between 78.6% and 88.6%. ZEN recovery from culture media was 96.3% at the spiked level of 500 µg/kg. Eighty-three samples of DDGS feed, corn feed and other fee ingredients were collected from 11 provinces of China and analysed for ZEN. Average ZEN levels were 563.4 µg/kg for DDGS feed, 393.1 µg/kg for corn feed and 65.7 µg/kg for other feed ingredients. Eighteen Fusarium species such as Fusarium graminearum which could produce ZEN were isolated from corn feed and other feed ingredients.
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Anticuerpos Monoclonales , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Fusarium , Zea mays/microbiología , Zearalenona/análisis , Animales , China , Fusarium/genética , Fusarium/metabolismo , Humanos , Reacción en Cadena de la PolimerasaRESUMEN
Type I collagen is a major extracellular matrix component and its hierarchical structure plays an essential role in the regulation of cellular behavior. Here, we have analyzed the changes in the morphological, chemical, and mechanical properties of collagen fibrils induced by acidic and thermal treatments and the influence on the cellular response of MC3T3-E1 cells. Morphological changes induced by the disintegration of the fibrillar structure of collagen were observed using atomic force microscopy. The changes in the surface chemistry due to the disassembly of native collagen fibrils were observed using time-of-flight secondary ion mass spectroscopy (ToF-SIMS). ToF-SIMS spectra were very sensitive to changes in the molecular configuration of the collagen fibrils induced by acidic and thermal treatments due to the extreme surface specificity. In addition, ToF-SIMS showed clear and reproducible changes in the surface amino acid composition corresponding to the acidic and thermal treatments of collagen fibrils. Based on the quantitative map of surface elastic modulus measured by contact-resonance force microscopy, acid and thermally treated collagen showed a lower elastic modulus than native collagen fibrils. Compared with native collagen fibrils, reduced cell spreading and decreased viability of MC3T3-E1 cells were observed on both the acid and thermally treated collagen.