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The geometric and electronic characteristics of phosphorus-atom doped aluminum nanoclusters, AlnPm (n = 7-17, m = 1 and 2), were investigated through a combination of experiments and theoretical calculations. The size dependences of the ionization energy (Ei) for AlnPm NCs exhibit a local minimum of 5.37 eV at Al12P1, attributed to an endohedral P@Al12 superatom (SA). This SA originates from an excess electron toward the 2P shell closing (40e), coexisting with an exohedral isomer featuring a vertex P atom. The stability of the endohedral P@Al12 is further enhanced in its cationic state compared to the exohedral isomer, when complexed with a fluorine (F) atom, forming an SA salt denoted as P@Al12+F- with an elevated Ei ranging from 6.42 to 7.90 eV. In contrast, for the anionic Al12P1-, the exohedral form is found to be more stable than the endohedral one using anion photoelectron spectroscopy and calculations. The geometric and electronic robustness of neutral P@Al12 SAs against electron donation and acceptance is discussed in comparison to rare-gas-like Si@Al12 SAs.
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Silver nanoclusters (Agn NCs) exhibit a remarkable optical property known as localized surface plasmon resonance (LSPR) in the visible to ultraviolet wavelengths. In this study, we address the size gap in LSPR responses between small NCs and nano-islands by synthesizing large Agn NCs with a countable number of atoms (n = 70-100) using a magnetron sputtering method, which were precisely size-selected and soft-landed onto substrates. The monodispersed Agn NCs were immobilized on a pre-decorated substrate with fullerene (C60) molecules, and their LSPR behaviors were characterized using two-photon photoemission (2PPE) spectroscopy. Due to the distinct polarization selectivity of incident light associated with LSPR, the intensity ratio between p- and s-polarized lights (Ip/Is) in 2PPE spectroscopy serves as a reliable indicator of LSPR and its structural correlations. From n = 70 to 100, the Ip/Is value gradually decreases as the cluster size increases. This decrease is attributed to the enhancement of s-polarized light (Is), indicating that large Agn NCs on a C60 substrate undergo a deformation from spherical to flattened geometries, particularly above approximately n = 55.
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Nintedanib (NTD), approved for the treatment of idiopathic pulmonary fibrosis and advanced non-small cell lung cancer, is one of brick dusts with high melting point. Although NTD has been marketed as Ofev®, a soft capsule of NTD ethanesulfonate (NTD-ESA) suspended in oil components, the oral bioavailability is quite low and highly variable. To improve the oral absorption behavior of NTD, we prepared SNEDDS formulation containing NTD-(+)-10-camphorsulfonic acid (CSA) complex with 2% HPMCP-50. CSA disrupted the high crystallinity of NTD-ESA and the formed complex, NTD-CSA, was found to be amorphous by DSC and XRPD. NTD-CSA provided solubilities in various vehicles much higher than NTD-ESA. Under the gastric luminal condition, NTD-CSA SNEDDS with or without 2% HPMCP-50 and NTD-CSA powder indicated very good dissolution of NTD from early time periods, while NTD was gradually dissolved until around 60 min from NTD-ESA and Ofev®. Under the small intestinal luminal condition, in contrast, both NTD-CSA SNEDDS formulations almost completely dissolved NTD throughout the experiments, while Ofev®, NTD-CSA, and NTD-ESA exhibited a very poor dissolution of NTD. In the in vivo absorption study, NTD-CSA SNEDDS with 2% HPMCP-50 significantly improved NTD absorption and reduced the inter-individual variation in oral absorption behavior compared with Ofev®.
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Indoles , Indoles/farmacocinética , Indoles/administración & dosificación , Indoles/química , Administración Oral , Animales , Masculino , Solubilidad , Ratas Sprague-Dawley , Disponibilidad Biológica , Absorción Intestinal , RatasRESUMEN
The silicon cage nanoclusters encapsulating a tantalum atom, termed Ta@Si16, exhibit characteristics of alkali metal "superatoms (SAs)". Despite this conceptual framework, the precise structures of Ta@Si16 and Ta@Si16+ remain unclear in quantum calculations due to three energetically close structural isomers: C3v, Td, and D4d structures. To identify the geometrical structure of Ta@Si16 SAs, structural analysis was conducted using extended X-ray absorption fine structure (EXAFS) with a high-intensity monochromatic X-ray source, keeping anaerobic conditions. Focusing on "superordered" films, which constitute amorphous thin films composed solely of Ta@Si16 SAs, this analysis preserved locally ordered structures. Spectral comparisons between experimental and simulated Ta L3-edge EXAFS unveil that Ta@Si16 SAs on a substrate adopt a C3v-derived structure, while Si K-edge EXAFS introduces spectral ambiguity in structural identifications, attributed to both intracluster and intercluster scatterings. These findings underscore the significance of locally ordered structure analyses in understanding and characterizing novel nanoscale materials.
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Elemental substitution and doping validate the optimization of chemical and physical properties of functional materials, and the composition ratio of the substituting atoms generally determines their properties by changing their geometric and electronic structures. For atomically precise nanoclusters (NCs) consisting of countable atom aggregates, the composition can be controlled accurately to provide an ideal model to study the heteroatom substitution effects. Since aluminum (Al) and boron (B) both belong to group 13 in the periodic table, the effect of B atom substitution on Aln NCs can be investigated while maintaining the total number of valence electrons in AlnBm NCs. In this study, oxidative reactivities of small Al NCs with B atom substitution are studied for AlnBm NCs (m = 1, n = 6-14 and m = 2, n = 11) supported on organic surfaces by using X-ray photoelectron spectroscopy and oxygen molecule (O2) exposure measurements. Before completing the endohedral B@Al12- superatomic NC, one B atom substitution in Al NCs (AlnB) enhances oxidative reactivities 3-20 times compared to those of Aln+1, particularly for n ≤ 11. When one Al atom of Al12B is further substituted by a B atom to form Al11B2, the reactivity drastically increases (6.6 × 102 times), showing that the B atom substitution makes the NC chemically active or inactive geometrically depending on the exohedral or endohedral site for the B atom in the Al NC. In addition, density functional theory calculations show that the electronegative B atom contributes to forming a locally positive Al site to facilitate O2 adsorption except in Al12B, in which the B atom is geometrically shielded by the surface of the Al12 cage in B@Al12.
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A 72-year-old female had persistent severe chest pain while climbing stairs. She was diagnosed as having acute coronary syndrome, and underwent an emergency coronary angiography (CAG). The right coronary artery (RCA) ostium was sub-totally occluded. Echocardiography revealed a 10 mm mobile mass at the right coronary cusp of the aortic valve. To avoid total obustruction on two drug eluting stents were placed at the RCA ostium so as to have the proximal end protrude into the right Valsalva sinus. Thus, her hemodynamic condition was stabilized. The tumor was surgically resected and the stents were easily removed. Pathologically, the tumor was papillary fibroelastoma. Postoperative aortic regurgitation was minimal echocardiography, and CAG showed normal RCA.
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Síndrome Coronario Agudo , Insuficiencia de la Válvula Aórtica , Fibroelastoma Papilar Cardíaco , Fibroma , Humanos , Femenino , Anciano , Síndrome Coronario Agudo/diagnóstico por imagen , Síndrome Coronario Agudo/etiología , Síndrome Coronario Agudo/cirugía , Fibroelastoma Papilar Cardíaco/patología , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Angiografía Coronaria , Fibroma/complicaciones , Fibroma/diagnóstico por imagen , Fibroma/cirugíaRESUMEN
Coronavirus disease 2019 (COVID-19) is associated with endocrine disorders, but their long-term clinical course remains unclear. We here report the 15-month clinical course for an individual with multiple endocrine disorders of the pituitary gland and testis likely triggered by COVID-19. A 65-year-old man with no history of endocrinopathy was admitted for acute COVID-19 pneumonia. Although his respiratory condition improved after administration of antiviral drugs, his blood pressure dropped suddenly to a preshock level and was refractory to vasopressors. The circulating adrenocorticotropic hormone (ACTH) and cortisol concentrations were low, and secondary adrenal insufficiency was suspected. Administration of hydrocortisone rapidly ameliorated the hypotension, and the patient was discharged taking 15 mg of hydrocortisone daily. An insulin tolerance test performed 3 months later revealed impaired ACTH, cortisol, and growth hormone (GH) responses, indicative of combined hypopituitarism. The patient also manifested symptoms of hypogonadism, and a hormonal workup suggested primary hypogonadism. At 12 months after discharge, GH and ACTH responses had recovered completely and partially, respectively. After another 3 months, basal ACTH and cortisol levels had been restored to the normal range and the patient discontinued hydrocortisone replacement without exacerbation of symptoms, although his hypogonadism persisted. The patient thus developed transient GH and ACTH deficiency that lasted for more than a year as well as persistent primary hypogonadism during intensive care for COVID-19. Certain prolonged symptoms of COVID-19 might be accounted for by such hormonal disturbance.
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Tratamiento Farmacológico de COVID-19 , COVID-19 , Hormona de Crecimiento Humana , Hipogonadismo , Masculino , Humanos , Anciano , Hormona Adrenocorticotrópica , Hormona del Crecimiento , Hidrocortisona/uso terapéutico , COVID-19/complicaciones , Hormona de Crecimiento Humana/uso terapéutico , TestosteronaRESUMEN
A 35-years-old pregnant woman with Marfan's syndrome visited the emergent department. She had sudden severe back pain. She was at the 20th week of gestation. An emergent chest computed tomo-graphy scan showed Stanford type B acute aortic dissection. After admission, strict blood pressure control was started. According to aortic valve insufficiency and fluid retention with pregnancy, acute heart and respiratory failure was getting worse. It seemed risky for both mother and the fetus to continue pregnancy. After sincere and detailed discussion between the patient and our multidisciplinary medical team, the patient decided to continue pregnancy. An urgent Bentall operation was performed. A careful attention was paid for the fetus during and after the surgery. Strict blood pressure control was also continued. The mother and the 30-week-gestation newborn recovered uneventfully. During four years of follow-up, thoracic and thoraco-abdominal aortic replacement was performed. The patient survived all of these procedures without any complication.
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Aneurisma de la Aorta Torácica , Disección Aórtica , Síndrome de Marfan , Adulto , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/etiología , Disección Aórtica/cirugía , Aorta/cirugía , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/etiología , Aneurisma de la Aorta Torácica/cirugía , Femenino , Humanos , Recién Nacido , Síndrome de Marfan/complicaciones , Síndrome de Marfan/cirugía , Embarazo , Mujeres EmbarazadasRESUMEN
Objectives: The objectives of this study were to evaluate the results when tissue-engineered vascular grafts (TEVGs) are used as alternatives to autologous pericardium for surgically augmenting the pulmonary artery (PA) or aortic valve. Methods: TEVG molds were embedded into subcutaneous spaces for more than 4 weeks preoperatively. Since 2014, 6 patients have undergone PA reconstruction, whereas 1 has undergone aortic valve plasty (AVP) with TEVGs. The time from mold implantation to the operation was 8.9 (range, 6.0-26.4) months. The age and body weight at the time of operation were 2.7 (range, 1.8-9.2) and 11.6 (range, 7.9-24.4) kg, respectively. Concomitant procedures comprised the Rastelli, palliative Rastelli, and Fontan operations in 2, 2, and 1 patient, respectively. Results: The median follow-up period was 14.4 (range, 3-39.6) months. There were no early or late mortalities. Moreover, there were no TEVG-related complications, including aneurysmal changes, degeneration, and infection. In 5 patients who underwent PA augmentation, the postoperative PA configuration was satisfactorily dilated. The reconstructed aortic valve function was good in the patient who underwent AVP. Decreased leaflet flexibility due to leaflet thickening was not observed. One patient had postoperative PA re-stenosis; therefore, re-PA augmentation with TEVGs was performed. On histological examination, TEVGs consisted of collagen fibers and few fibroblasts, and elastic fiber formation and/or smooth muscle cells were not observed. Conclusions: The midterm results of PA reconstruction and AVP with TEVGs were satisfactory. TEVGs might be a useful alternative to autologous pericardium in pediatric cardiovascular surgeries that often require multistage operations.
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Aluminum nanoclusters (Aln NCs), particularly Al13- (n = 13), exhibit superatomic behavior with interplay between electron shell closure and geometrical packing in an anionic state. To fabricate superatom (SA) assemblies, substrates decorated with organic molecules can facilitate the optimization of cluster-surface interactions, because the molecularly local interactions for SAs govern the electronic properties via molecular complexation. In this study, Aln NCs are soft-landed on organic substrates pre-deposited with n-type fullerene (C60) and p-type hexa-tert-butyl-hexa-peri-hexabenzocoronene (HB-HBC, C66H66), and the electronic states of Aln are characterized by X-ray photoelectron spectroscopy and chemical oxidative measurements. On the C60 substrate, Aln is fixed to be cationic but highly oxidative; however, on the HB-HBC substrate, they are stably fixed as anionic Aln- without any oxidations. The results reveal that the careful selection of organic molecules controls the design of assembled materials containing both Al13- and boron-doped B@Al12- SAs through optimizing the cluster-surface interactions.
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Poorly water-soluble and poorly lipid-soluble drugs are called as "brick dust" and it is very hard for them to be formulated as some dosage form which can provide an effective bioavailability after oral administration. Mebendazole (MBZ), an anti-helminthic drug having anti-cancer properties, is one of the brick dusts and its poor bioavailability has been well known. The strategy of the current study was to improve the oral absorption of MBZ by SNEDDS formulation prepared by utilizing an MBZ-counter ion complex, of which the formation would disrupt the high crystallinity of MBZ. Among five different counter ions examined, (+)-10-camphorsulfonic acid (CSA), 2-naphthalene-sulfonic acid (NSA) and p-toluenesulfonic acid (TSA) largely improved MBZ solubility in the SNEDDS vehicle by forming the complex with MBZ. The solid state of these complexes, MBZ-CSA, MBZ-NSA and MBZ-TSA, was suggested to be amorphous by XRPD and DSC. SNEDDS formulations of the three complexes extensively improved MBZ dissolution under gastric and intestinal luminal conditions, compared with MBZ crystalline powder. However, since the dissolved concentrations of MBZ were time-dependently decreased so much by precipitation, we tried to maintain the high dissolution property by applying some polymer for SNEDDS preparation of MBZ-CSA which provided the highest solubility in the SNEDDS vehicle. Among ten different polymers examined, HPMCP-50 successfully maintained the high dissolution property of MBZ-CSA SNEDDS under both gastric and intestinal luminal conditions. In the in vivo oral administration study, SNEDDS preparations for the three MBZ complexes significantly improved MBZ absorption compared with MBZ crystalline powder, but 2% HPMCP-50-containing SNEDDS of MBZ-CSA provided further improvement of MBZ absorption, resulting in around 10-fold of crystalline powder in AUC.
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Mebendazol , Nanopartículas , Administración Oral , Disponibilidad Biológica , Sistemas de Liberación de Medicamentos , Polvo , Emulsiones , Tamaño de la Partícula , Polímeros , Solubilidad , AguaRESUMEN
BACKGROUND: We have previously applied in vivo tissue-engineered vascular grafts constructed in patients' subcutaneous spaces. However, since the formation of these vascular grafts depends on host health, their application is challenging in patients with suppressed regenerative ability. Therefore, the allogeneic implantation of grafts from healthy donors needs to be evaluated. This study aimed to fabricate allogeneic cardiovascular grafts in animals. MATERIALS AND METHODS: Silicone rod molds were implanted into subcutaneous pouches in dogs; the implants, along with surrounding connective tissues, were harvested after four weeks. Tubular connective tissues were decellularized and stored before they were cut open, trimmed to elliptical sheets, and implanted into the common carotid arteries of another dog as vascular patches (n = 6); these were resected and histologically evaluated at 1, 2, and 4 weeks after implantation. RESULTS: No aneurysmal changes were observed by echocardiography. Histologically, we observed neointima formation on the luminal graft surface and graft wall cell infiltration. At 2 and 4 weeks after implantation, α-SMA-positive cells were observed in the neointima and graft wall. At 4 weeks after implantation, the endothelial lining was observed at the grafts' luminal surfaces. CONCLUSION: Our data suggest that decellularized connective tissue membranes can be prepared and stored for later use as allogeneic cardiovascular grafts.
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Bioprótesis , Trasplante de Células Madre Hematopoyéticas , Animales , Prótesis Vascular , Tejido Conectivo , Perros , Humanos , Ingeniería de TejidosRESUMEN
Delicate animal experiments and microdose clinical trials using short-lived radioisotopes require rapid preparation with high accuracy and careful attention to safety within a limited timeframe. We have developed an open-style electrowetting on dielectric (EWOD) device containing dimple structures for the rapid preparation of radiolabelled reagents. The device was demonstrated by automatic preparation of a technetium diethylenetriamine pentaacetate (99mTc-DTPA) with high chelation efficiency (99.7 ± 0.13%). Additionally, we demonstrated the single-photon emission computed tomography/computed tomography imaging of mouse kidney using the 99mTc-DTPA prepared with the EWOD device. The obtained organ tomographic images were sufficient for the evaluation of mouse models for specific diseases. These results indicate that manual radiolabelling for a small amount of nuclear medicine can be replaced by a process using the proposed EWOD device as a human error reduction technique.
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In vivo tissue-engineered vascular grafts constructed in the subcutaneous spaces of graft recipients have functioned well clinically. Because the formation of vascular graft tissues depends on several recipient conditions, chemical pretreatments, such as dehydration by ethanol (ET) or crosslinking by glutaraldehyde (GA), have been attempted to improve the initial mechanical durability of the tissues. Here, we compared the effects of short-duration (10 min) chemical treatments on the mechanical properties of tissues. Tubular tissues (internal diameter, 5 mm) constructed in the subcutaneous tissues of beagle dogs (4 weeks, n = 3), were classified into three groups: raw tissue without any treatment (RAW), tissue dehydrated with 70% ET (ET), and tissue crosslinked with 0.6% GA (GA). Five mechanical parameters were measured: burst pressure, suture retention strength, ultimate tensile strength (UTS), ultimate strain (%), and Young's modulus. The tissues were also autologously re-embedded into the subcutaneous spaces of the same dogs for 4 weeks (n = 2) for the evaluation of histological responses. The burst pressure of the RAW group (1275.9 ± 254.0 mm Hg) was significantly lower than those of ET (2115.1 ± 262.2 mm Hg, p = 0.0298) and GA (2570.5 ± 282.6 mm Hg, p = 0.0017) groups. Suture retention strength, UTS or the ultimate strain did not differ significantly among the groups. Young's modulus of the ET group was the highest (RAW: 5.41 ± 1.16 MPa, ET: 12.28 ± 2.55 MPa, GA: 7.65 ± 1.18 MPa, p = 0.0185). No significant inflammatory tissue response or evidence of residual chemical toxicity was observed in samples implanted subcutaneously for four weeks. Therefore, short-duration ET and GA treatment might improve surgical handling and the mechanical properties of in vivo tissue-engineered vascular tissues to produce ideal grafts in terms of mechanical properties without interfering with histological responses.
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Bioprótesis , Prótesis Vascular , Ingeniería de Tejidos , Injerto Vascular , Animales , Perros , Módulo de Elasticidad , FemeninoRESUMEN
Computational fluid dynamics (CFD) analysis using computed tomography images can reveal the details of the blood flow in cardiovascular disease. In double aortic arch, it is difficult to assess the hemodynamics because of the strong influence of various anatomical features, such as the angle of the aortic bifurcation. In the present study, we reported that CFD analysis is a valuable method for hemodynamic assessment in patients with double aortic arch.
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Hidrodinámica , Anillo Vascular , Aorta Torácica/diagnóstico por imagen , Simulación por Computador , Hemodinámica , Humanos , Modelos Cardiovasculares , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVES: The actual underlying mechanisms of acute type A aortic dissection (AAAD) are not well understood. The present study aimed to elucidate the mechanism of AAAD using computational fluid dynamics (CFD) analysis. METHODS: We performed CFD analysis using patient-specific computed tomography imaging in 3 healthy control cases and 3 patients with AAAD. From computed tomography images, we made a healthy control model or pre-dissection model for CFD analysis. Pulsatile cardiac flow during one cardiac cycle was simulated, and a three-dimensional flow streamline was visualized to evaluate flow velocity, wall shear stress and oscillatory shear index (OSI). RESULTS: In healthy controls, the transvalvular aortic flow was parallel to the ascending aorta. There was no spotty high OSI area at the ascending aorta. In pre-dissection patients, accelerated transvalvular aortic flow was towards the posterolateral ascending aorta. The vortex flow was observed on the side of the lesser curvature in mid-systole and expanded throughout the entire ascending aorta during diastole. Systolic wall shear stress was high due to the accelerated aortic blood flow on the side of the greater curvature of the ascending aorta. On the side of the lesser curvature, high OSI areas were observed around the vortex flow. In all pre-dissection cases, a spotty high OSI area was in close proximity to the actual primary entry site of the future AAAD. CONCLUSIONS: The pre-onset high OSI area with vortex flow is closely associated with the future primary entry site. Therefore, we can elucidate the mechanism of AAAD with CFD analysis.
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Disección Aórtica , Hidrodinámica , Disección Aórtica/diagnóstico por imagen , Aorta/diagnóstico por imagen , Velocidad del Flujo Sanguíneo , Simulación por Computador , Hemodinámica , Humanos , Modelos Cardiovasculares , Estrés MecánicoRESUMEN
The plasmonic response of metallic nanostructures plays a key role in amplifying photocatalytic and photoelectric conversion. Since the plasmonic behavior of noble metal nanoparticles is known to generate energetic charge carriers such as hot electrons, it is expected that the hot electrons can enhance conversion efficiency if they are transferred into a neighboring molecule or semiconductor. However, the method of transferring the energized charge carriers from the plasmonically generated hot electrons to the neighboring species remains controversial. Herein, we fabricated a molecularly well-defined heterointerface between the size-selected plasmonic noble-metal nanoclusters (NCs) of Agn (n = 3-55)/Aun (n = 21) and the organic C60 film to investigate hot electron generation and relaxation dynamics using time-resolved two-photon photoemission (2PPE) spectroscopy. By tuning the NC size and the polarization of the femtosecond excitation photons, the plasmonic behavior is characterized by 2PPE intensity enhancement by 10-100 times magnitude, which emerge at n ≥ 9 for Agn NCs. The 2PPE spectra exhibit contributions from low-energy electrons forming coherent plasmonic currents and hot electrons with an excitation energy up to photon energy owing to two-photon excitation of an occupied state of the Agn NC below the Fermi level. The time-resolved pump-probe measurements demonstrate that plasmon dephasing generates hot electrons which undergo electron-electron scattering. However, no photoemission occurs via the charge transfer state forming Agn+C60- located in the vicinity of the Fermi level. Thus, this study reveals the mechanism of ultrafast confined hot electron relaxation within plasmonic Agn NCs at the molecular heterointerface.
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PURPOSE: Autologous pericardium is an ideal material for cardiovascular reconstruction including pulmonary artery plasty. Despite the fact that dehydration by ethanol has been used to improve its surgical handling, the effects of the ethanol on mechanical properties of the pericardium have not been previously investigated. The effects of short-duration ethanol dehydration on the mechanical properties of porcine pericardium were evaluated. METHODS: Porcine pericardia (n = 3) were separated into three groups: the raw group with no treatments (RAW), the group immersed in 70% ethanol for 10 min (ET group), and the group immersed in 0.6% glutaraldehyde for 10 min (GA). We measured five parameters of mechanical properties as specified in ISO 7198. RESULTS: ET treatment improved surgical handling as well as GA treatment. There were no significant differences in burst pressure (P = 0.639), suture retention strength (P = 0.529), ultimate tensile strength (UTS; P = 0.486), or Young's modulus (P = 0.408). Only the ultimate strain of the GA group was significantly higher among the three groups (RAW: 33.34% ± 2.02%, ET: 37.48% ± 1.84%, GA: 44.74% ± 2.87%; P = 0.046). CONCLUSIONS: Short-duration ethanol dehydration did not compromise its mechanical properties while maintaining its surgical handling improvements.
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Etanol/química , Fijadores/química , Pericardio/cirugía , Técnicas de Sutura , Fijación del Tejido/métodos , Animales , Desecación , Módulo de Elasticidad , Glutaral/química , Sus scrofa , Resistencia a la Tracción , Factores de Tiempo , Recolección de Tejidos y ÓrganosRESUMEN
PURPOSE: This study sought to evaluate the histologic and mechanical properties of autologous in vivo tissue-engineered vascular grafts (in vivo TEVGs) used for pediatric heart surgery. DESCRIPTION: Molds of in vivo TEVGs made of silicone drain tubes were embedded into subcutaneous spaces in 2 boys during their first operation and were used as patch materials to treat pulmonary artery stenosis during the second operation. The remaining pieces of the patches were evaluated histologically and mechanically. EVALUATION: In vivo TEVGs had very smooth luminal surfaces, and their walls mainly comprised collagen fibers and small numbers of fibroblasts. Mean wall thickness was 200 µm, mean suture retention strength was 2.26 N, and burst pressure was 3057 mm Hg. CONCLUSIONS: Human in vivo TEVGs mainly comprise collagen fibers, and their mechanical properties prove them safe for pulmonary arterioplasty. Therefore, human in vivo TEVGs may be promising alternatives to autologous pericardium for pediatric cardiovascular surgical procedures that often require multistage operations.
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Prótesis Vascular , Pericardio/citología , Estenosis de Arteria Pulmonar/cirugía , Ingeniería de Tejidos/métodos , Procedimientos Quirúrgicos Cardíacos/métodos , Preescolar , Estudios de Seguimiento , Humanos , Lactante , Masculino , Diseño de Prótesis , Estudios Retrospectivos , Estenosis de Arteria Pulmonar/congénitoRESUMEN
A 80-year-old man was transferred to our hospital for hemoptysis caused by erosion(perforation) of thoracic aortic stent graft infection into the airway. Blood cultures on admission detected Gram-positive rods, and a microarray-based, multiplexed, automated molecular diagnosis instrument (Verigene® system) identified Listeria spp. Although Listeria monocytogenes is rare organism of stent graft infection, we were able to start appropriate antibiotic therapy on the second hospital day due to rapid identification of bacteria. Verigene® system is considered to be useful in severe infectious diseases including stent graft infections, even if the causative organism is rare.