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OBJECTIVE: This study reports the results of a steerable delivery system under the guidance of transesophageal echocardiography (TEE) for the treatment of transjugular closure of secundum atrial septal defects (ASD). METHODS: From July 2015 to May 2016, 33 patients underwent transjugular closure of a secundum ASD under general anesthesia with TEE guidance. The right internal jugular vein was punctured and a FuStar™ steerable sheath was implanted into the right atrium and aligned vertically with the septum, and a closure device was deployed to close the defect. RESULTS: Thirty-two patients with an ASD were successfully occluded; one patient required ASD closure on cardiopulmonary bypass. Procedure time ranged from 5 to 15 (8.2 ± 3.8) min. The length of stay was three to five days after the operation. The follow-up time ranged from 1.1 to 11.0 (5.5 ± 1.5) months. There was no valve regurgitation, no malignant arrhythmias, no device dislocation, or other serious complications. CONCLUSIONS: A steerable delivery system under the guidance of TEE is a safe, effective, and cosmetic method for the transjugular closure of secundum ASDs.
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Cateterismo Cardíaco/métodos , Procedimientos Quirúrgicos Cardíacos/métodos , Defectos del Tabique Interatrial/cirugía , Dispositivo Oclusor Septal , Cirugía Asistida por Computador/métodos , Adolescente , Adulto , Niño , Preescolar , Ecocardiografía Transesofágica , Femenino , Estudios de Seguimiento , Defectos del Tabique Interatrial/diagnóstico , Humanos , Venas Yugulares , Masculino , Estudios Retrospectivos , Adulto JovenRESUMEN
Blending poly (butylene adipate-co-terephthalate) (PBAT) and polylactic acid (PLA) is a cost-effective strategy to obtain biodegradable plastic with complementary properties. However, the incompatibility between PBAT and PLA is a great challenge for fabricating high-performance composite films. Herein, the ethyl acetate fractionated lignin with the small glass transition temperature and low molecular weight was achieved and incorporated into the PBAT/PLA composite as a compatibilizer. The fractionated lignin can be uniformly dispersed within the PBAT/PLA matrix through a melt blending process and interact with the molecular chain of PBAT and PLA as a bonding bridge, which enhances the intermolecular interactions and reduces the interfacial tension of PBAT/PLA. By adding fractionated lignin, the tensile strength of the PBAT/PLA composite increased by 35.4 % and the yield strength increased by 37.7 %. Owing to lignin, the composite films possessed the ultraviolet shielding function and exhibited better water vapor barrier properties (1.73 ± 0.08 × 10-13 g·cm/cm2·s·Pa). This work conclusively demonstrated that fractionated lignin can be used as a green compatibilizer and a low-cost functional filler for PBAT/PLA materials, and provides guidance for the application of lignin in biodegradable plastics.
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Alquenos , Plásticos Biodegradables , Lignina , Ácidos Ftálicos , Adipatos , Poli A , PoliésteresRESUMEN
Kaidu River basin is a typical mountain oasis ecosystem in the northwest inland. Its hydrochemical environment information is of great significance to understand the regional hydrological process and optimize the allocation of water resources. Based on the collection of samples of various water bodies in mountainous and oasis areas in different seasons in 2020, this study analyzed the water chemical characteristics and hydraulic links in this region. The results showed that:â the water body in the study area was slightly alkaline as a whole, and the pH and TDS values showed the spatial changes of low in the oasis area and high in the mountain area; HCO3- and Ca2+ were the main anions and cations. The regional hydrochemical type was mostly HCO3--Ca2+, and the hydrochemical type of groundwater in the oasis area was more complex than that in the mountainous area. Regional hydrochemical changes were mainly controlled by rock weathering and human disturbance. â¡ The δ18O and δD values of the river water showed the seasonal changes of dilution in summer and enrichment in spring, whereas groundwater was depleted in winter and spring and enriched in autumn. Precipitation and glacial water did not change significantly within a year. In space, the δ18O and δD values of river water and groundwater showed the law of enrichment in the oasis area and dilution in the mountainous area. ⢠The relationship between surface water and groundwater in the study area was close, and the transformation was frequent in summer. The relationship between surface water and groundwater in the oasis area was closer than that in the mountainous area. Groundwater in the oasis area was recharged by groundwater in the previous period, river water, and precipitation, and the recharge rate was usually groundwater in the previous period>river water>precipitation.
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Utilizing starch, an abundant polysaccharide, as the renewable filler to blend with poly(butylene adipate-co-terephthalate) (PBAT) is a feasible tactic to construct cost-effective and high-performance biodegradable materials. It's worth noting that the thermal processing properties of starch can be manipulated by its plasticized behavior. Herein, epoxidized soybean oil (ESO) and glycerol were used as the plasticizer for native corn starch and the plasticized starch was integrated with PBAT to manufacture starch-based biodegradable blend films. ESO breaks the hydrogen bonds between starch chains through the fatty chains grafting reaction and increases the distance between starch molecular chains due to the large molecular weight of ESO. Meanwhile, glycerol molecules are incorporated into the starch molecular chains, and fatty chains grafted starch chains, effectively reducing the intermolecular forces of molecular chains. On account of the synergistic plasticization of ESO and glycerol which possess good compatibility with PBAT, the PSG20E10 blend film achieved a tensile strength, an elongation at break of 16.11 MPa and 612.09 %, and the balanced water and oxygen permeability properties.
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Glicerol , Poliésteres , Poliésteres/química , Almidón/química , AdipatosRESUMEN
Complex and heterogeneous structures of lignin impede its further conversion and valorization. Herein, three technical lignins (from softwood, hardwood, and grass) were fractionated with acetone solvent to reduce their structural heterogeneity, which were then blended with poly-(butylene adipate-co-terephthalate) (PBAT) to fabricate biodegradable bio-composites. Macromolecular structures of lignins and their effects on the properties of lignin/PBAT composites were thoroughly investigated. Results showed that all fractionated lignin composites displayed better properties. Particularly, the raw and fractionated softwood lignin-based composites exhibited superior performance compared with others. Benefiting from the lower molecular weight, hydroxyl groups, and condensation, acetone fractionated softwood lignin presented the lowest Tg (115.7 °C), achieving ideal melt miscibility and interfacial interaction between lignin and PBAT. The decreased Tg of lignin facilitated the lignin dispersion in the matrix and increase the mechanical strength of the composites. Overall, the fractionated technical lignin possessed desirable physical and chemical structure features, conferring composites good miscibility and mechanical properties.
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Lignina , Poliésteres , Acetona , Adipatos , Alquenos , Lignina/química , Ácidos Ftálicos , Poliésteres/químicaRESUMEN
BACKGROUND: LncRNA AK044604 (regulator of insulin sensitivity and autophagy, Risa) and autophagy-related factors Sirt1 and GSK3ß play important roles in diabetic nephropathy (DN). In this study, we sought to explore the effect of Risa on Sirt1/GSK3ß-induced podocyte injury. METHODS: Diabetic db/db mice received Risa-inhibition adeno-associated virus (AAV) via tail vein injection, and intraperitoneal injection of lithium chloride (LiCl). Blood, urine, and kidney tissue samples were collected and analyzed at different time points. Immortalized mouse podocyte cells (MPCs) were cultured and treated with Risa-inhibition lentivirus (LV), EX-527, and LiCl. MPCs were collected under different stimulations as noted. The effects of Risa on podocyte autophagy were examined by qRT-PCR, Western blotting analysis, transmission electron microscopy, Periodic Acid-Schiff staining, and immunofluorescence staining. RESULTS: Risa and activated GSK3ß were overexpressed, but Sirt1 was downregulated in DN mice and high glucose-treated MPCs (P < 0.001, db/m vs. db/db, NG or HM vs. HG), which was correlated with poor prognosis. Risa overexpression attenuated Sirt1-mediated downstream autophagy levels and aggravated podocyte injury by inhibiting the expression of Sirt1 (P < 0.001, db/m vs. db/db, NG or HM vs. HG). In contrast, Risa suppression enhanced Sirt1-induced autophagy and attenuated podocyte injury, which could be abrogated by EX-527 (P < 0.001, db/db + Risa-AAV vs. db/db, HG + Risa-LV vs. HG). Furthermore, LiCl treatment could restore GSK3ß-mediated autophagy of podocytes (P < 0.001, db/db + LiCl vs. db/db, HG + LiCl vs. HG), suggesting that Risa overexpression aggravated podocyte injury by decreasing autophagy. CONCLUSION: Risa could inhibit autophagy by regulating the Sirt1/GSK3ß axis, thereby aggravating podocyte injury in DN. Risa may serve as a therapeutic target for the treatment of DN.
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Diabetes Mellitus , Nefropatías Diabéticas , Glucógeno Sintasa Quinasa 3 beta , Podocitos , ARN Largo no Codificante , Sirtuina 1 , Animales , Autofagia/genética , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/metabolismo , Regulación hacia Abajo , Glucógeno Sintasa Quinasa 3 beta/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/farmacología , Ratones , Podocitos/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Largo no Codificante/farmacología , Sirtuina 1/genética , Sirtuina 1/metabolismo , Sirtuina 1/farmacologíaRESUMEN
BACKGROUND: Stress tolerance is one of the important desired microbial traits for industrial bioprocesses, and global regulatory protein engineering is an efficient approach to improve strain tolerance. In our study, IrrE, a global regulatory protein from the prokaryotic organism Deinococcus radiodurans, was engineered to confer yeast improved tolerance to the inhibitors in lignocellulose hydrolysates or high temperatures. RESULTS: Three IrrE mutations were developed through directed evolution, and the expression of these mutants could improve the yeast fermentation rate by threefold or more in the presence of multiple inhibitors. Subsequently, the tolerance to multiple inhibitors of single-site mutants based on the mutations from the variants were then evaluated, and 11 mutants, including L65P, I103T, E119V, L160F, P162S, M169V, V204A, R244G, Base 824 Deletion, V299A, and A300V were identified to be critical for the improved representative inhibitors, i.e., furfural, acetic acid and phenol (FAP) tolerance. Further studies indicated that IrrE caused genome-wide transcriptional perturbation in yeast, and the mutant I24 led to the rapid growth of Saccharomyces cerevisiae by primarily regulating the transcription level of transcription activators/factors, protecting the intracellular environment and enhancing the antioxidant capacity under inhibitor environments, which reflected IrrE plasticity. Meanwhile, we observed that the expression of the wild-type or mutant IrrE could also protect Saccharomyces cerevisiae from the damage caused by thermal stress. The recombinant yeast strains were able to grow with glucose at 42 â. CONCLUSIONS: IrrE from Deinococcus radiodurans can be engineered as a tolerance-enhancer for Saccharomyces cerevisiae. Systematic research on the regulatory model and mechanism of a prokaryotic global regulatory factor IrrE to increase yeast tolerance provided valuable insights for the improvements in microbial tolerance to complex industrial stress conditions.
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Debugging a genome sequence is imperative for successfully building a synthetic genome. As part of the effort to build a designer eukaryotic genome, yeast synthetic chromosome X (synX), designed as 707,459 base pairs, was synthesized chemically. SynX exhibited good fitness under a wide variety of conditions. A highly efficient mapping strategy called pooled PCRTag mapping (PoPM), which can be generalized to any watermarked synthetic chromosome, was developed to identify genetic alterations that affect cell fitness ("bugs"). A series of bugs were corrected that included a large region bearing complex amplifications, a growth defect mapping to a recoded sequence in FIP1, and a loxPsym site affecting promoter function of ATP2 PoPM is a powerful tool for synthetic yeast genome debugging and an efficient strategy for phenotype-genotype mapping.