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1.
Inorg Chem ; 62(16): 6439-6446, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37053452

RESUMEN

A heterobimetallic coordination polymer [Au4(dppmt)4(AgCl)2]n (1) incorporating an in situ generated P-S ligand (dppmtH) was synthesized from the solvothermal reaction of Au(tht)Cl, AgCl, and dpppyatc in CH3CN/CH2Cl2 (dppmtH = (diphenylphosphino)methanethiol, tht = tetrahydrothiophene, dpppyatc = N,N-bis((diphenylphosphaneyl)methyl)-N-(pyridin-2-yl)-amino-thiocarbamide). The structure of 1 contains a one-dimensional helical Au-Au chain in which the unique [Au4Ag2S2] cluster units are connected by [Au2(dppmt)2] dimers. Upon excitation at 343 nm, 1 exhibited cyan (495 nm) phosphorescent emission at quantum yield (QY) = 22.3% and τ = 0.78 µs (λex = 375 nm). Coordination polymer 1 exhibited a rapid, selective, reversible, and visible vapor-chromic response on exposure to methanol (MeOH) vapor with its emission shifting to a more intense green (530 nm, λex = 388 nm) with QY = 46.8% and τ = 1.24 µs (λex = 375 nm). A polymethylmethacrylate film containing 1 served as a reversible chemical sensor for the sensitive detection of MeOH in air.

2.
Proc Natl Acad Sci U S A ; 117(44): 27412-27422, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33087562

RESUMEN

Nuclear receptor Nur77 participates in multiple metabolic regulations and plays paradoxical roles in tumorigeneses. Herein, we demonstrated that the knockout of Nur77 stimulated mammary tumor development in two mouse models, which would be reversed by a specific reexpression of Nur77 in mammary tissues. Mechanistically, Nur77 interacted and recruited corepressors, the SWI/SNF complex, to the promoters of CD36 and FABP4 to suppress their transcriptions, which hampered the fatty acid uptake, leading to the inhibition of cell proliferation. Peroxisome proliferator-activated receptor-γ (PPARγ) played an antagonistic role in this process through binding to Nur77 to facilitate ubiquitin ligase Trim13-mediated ubiquitination and degradation of Nur77. Cocrystallographic and functional analysis revealed that Csn-B, a Nur77-targeting compound, promoted the formation of Nur77 homodimer to prevent PPARγ binding by steric hindrance, thereby strengthening the Nur77's inhibitory role in breast cancer. Therefore, our study reveals a regulatory function of Nur77 in breast cancer via impeding fatty acid uptake.


Asunto(s)
Neoplasias de la Mama/patología , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , PPAR gamma/metabolismo , Fenilacetatos/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Proliferación Celular , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Ácidos Grasos/metabolismo , Femenino , Humanos , Estimación de Kaplan-Meier , Metabolismo de los Lípidos/efectos de los fármacos , Glándulas Mamarias Animales/patología , Ratones , Persona de Mediana Edad , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/agonistas , PPAR gamma/agonistas , Cultivo Primario de Células , Pronóstico , Proteolisis/efectos de los fármacos , Análisis de Matrices Tisulares , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/metabolismo , Ubiquitinación/efectos de los fármacos
3.
Br J Nutr ; : 1-11, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35057872

RESUMEN

The current study aimed to investigate the protective effects of dietary thiamine supplementation on the regulation of colonic integrity and mucosal inflammation in goats fed a high-concentrate (HC) diet. Twenty-four Boer goats (live weight of 35·62 (sem 2·4) kg) were allocated to three groups (CON: concentrate/forage = 30:70; HC; concentrate/forage = 70:30 and HCT: concentrate/forage = 70:30 with 200 mg thiamine/kg DMI) for 12 weeks. Results showed that compared with the HC treatment, the HCT group had a significantly higher ruminal pH value from 0 to 12 h after the feeding. The haematoxylin-eosin staining showed that desquamation and severe cellular damage were observed in the colon epithelium of the HC group, whereas the HCT group exhibited more structural integrity of the epithelial cell morphology. Compared with the HC treatment, the HCT group showed a markedly increase in pyruvate dehydrogenase and α-ketoglutarate dehydrogenase enzymes activity. The mRNA expressions in the colonic epithelium of SLC19A2, SLC19A3, SLC25A19, Bcl-2, occludin, claudin-1, claudin-4 and ZO-1 in the HCT group were significantly increased in comparison with the HC diet treatment. Compared with the HC treatment, the HCT diet significantly increased the protein expression of claudin-1 and significantly decreased the protein expression of NF-κB-related proteins p65. The results show that dietary thiamine supplementation could improve the colon epithelial barrier function and alleviate mucosal inflammation injury in goats after lipopolysaccharide and low pH challenge.

4.
Mol Biol Rep ; 49(9): 8197-8207, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35854052

RESUMEN

BACKGROUND: JQ1, a BRD4 inhibitor, first identified its therapeutic role in cancer, has gradually demonstrated a protective effect on the heart in recent years; however, it is unclear whether JQ1 also plays a role in LPS-induced cardiac dysfunction. METHODS AND RESULTS: A total of forty eight mice were randomly divided into control, LPS(7.5 mg/kg), and LPS + JQ1 (50 mg/kg). JQ1 was preprotected for 1 h, and LPS was stimulated for 12 h, mouse survival and cardiac function were observed, and histopathological, serum myocardial injury markers, and inflammatory indicators, and oxidative stress levels in heart tissue were examined. The experiment found that the cardiac BRD4 levels were upregulated and the heart severe damage in the LPS group compared with the control group. While compared with the LPS group, JQ1 preprotected increased survival rate and cardiac function, reducated cardiomypathological injury and CD45 infiltration, and reduced the release of LDH, CK-MB, IL-1, IL-18, reduced MDA generation, and increased SOD viability. In addition, JQ1 preprotected also upregulated SIRT1, and inhibited the expression of NLRP3, caspase-1p20, and GSDMD. Meanwhile, similar results were obtained in LPS-treated H9C2 cells, and further intervention with the SIRT1 inhibitor EX527 partially blocked the JQ1-mediated down regulation of NLRP3, caspase-1p20, and GSDMD. CONCLUSIONS: We propose that JQ1 may improve LPS-induced cardiac dysfunction by inhibiting SIRT1-dependent activation of NLRP3 inflammasomes, which may be a promising strategy for treating sepsis cardiomyopathy.


Asunto(s)
Cardiopatías , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Caspasas , Cardiopatías/inducido químicamente , Inflamasomas/metabolismo , Lipopolisacáridos/toxicidad , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteínas Nucleares , Sirtuina 1/metabolismo , Factores de Transcripción
5.
Ecotoxicol Environ Saf ; 222: 112520, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34280842

RESUMEN

Mineral development and metal smelting are the main sources of heavy metal pollution, and copper (Cu) and cadmium (Cd) are the most serious mineral elements in heavy metal pollution. Food chain is the main channel for Cu and Cd to enter human body. Excessive accumulation of Cu and Cd can lead to a variety of diseases and threaten human health. Therefore, it is urgent to repair Cu and Cd-contaminated soil. Previous several studies found that sulfur (S) and molybdenum (Mo) had the effect of alleviating the decrease of antioxidant capacity caused by heavy metal poisoning. To investigate the co-combinations of S and Mo fertilizations on antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-contaminated meadow, and explore the control methods of co-pollutions of Cu and Cd in natural pastures, fertilizing and grazing experiments were carried out in the Wumeng Prairie in the northwest of Guizhou Province, Southwest China. 24 hm2 Cu and Cd-polluted meadows were fenced, and were randomly divided into four groups with 3 replications per group and 2 hm2 per replication. The tested groups included the control group (no fertilizer) and the three treatment groups, applied 40 kg S + 1 kg Mo, 80 kg S + 2 kg Mo, and 120 kg S + 3 kg Mo per hectare for group I, group II, and group III, respectively. 72 healthy Guizhou semi-fine wool sheep (one year old, 33.9 ± 1.2 kg) were randomly assigned to the tested pastures with 18 sheep per group. The grazing experiment lasted for 60 days. The results showed that the contents of Mn, Zn, Mo, and S in herbage in fertilized pastures were higher than that in the control group (P < 0.05). The content of Cu in herbage in fertilized pastures was lower than that in the control group (P < 0.05). The contents of Mn, Zn, Mo, and S in serum of grazing Guizhou semi-fine wool sheep were higher than that in the control group (P < 0.05). The content of Cu in serum of grazing Guizhou semi-fine wool sheep was lower than that in the control group (P < 0.05). The levels of blood Hb, RBC, and PCV, and the activities of serum SOD, GSH-Px, T-AOC, CAT, and Cp in group Ⅲ were higher than that in the control group, group Ⅰ, and group Ⅱ (P < 0.05). The MDA content of sheep in group Ⅲ was lower than that in the other treatment sheep (P < 0.05). In summary, the combinations of S and Mo fertilizers influenced the mineral contents in herbage and serum of grazing Guizhou semi-fine wool sheep. The combinations of 120 kg S + 3 kg Mo fertilizer reduced the toxicity and improved antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-polluted grasslands.


Asunto(s)
Cadmio , Lana , Animales , Antioxidantes , Cadmio/toxicidad , Cobre/toxicidad , Fertilización , Humanos , Molibdeno/toxicidad , Ovinos , Azufre
6.
Biol Reprod ; 99(2): 461-472, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29272345

RESUMEN

Immunocastration via vaccination against gonadotropin-releasing hormone (GnRH) is an effective alternative to surgical castration in livestock. In this study, male mice were immunized with eight GnRH peptide derivatives. Two, which exhibited highly significant effects in mice, and one which exhibited the least significant effects were selected for active immunization of 13-month-old bulls. The effects of these GnRH vaccines on sexual development and meat quality in bulls were evaluated by examining testis length, serum hormone and GnRH antibody concentrations, observation of sexual behavior and testicular tissue sections, and evaluation of meat quality indexes. The results indicated that anti-GnRH titers increased rapidly (P < 0.05) and serum follicle stimulating hormone, luteinizing hormone, and testosterone concentrations decreased sharply after booster immunization (P < 0.05), while testis volumes were lower (P < 0.01), testicular growth was arrested and spermatogenesis inhibited in group C GnRH-treated versus control bull groups. Meat quality was not significantly different in immunocastrates relative to bulls in the control group. Our collective results provide a scientific basis to further clarify the mechanisms underlying GnRH-mediated regulation of livestock reproduction, and contribute to the development of an efficient, safe, and reversible immune castration vaccine.


Asunto(s)
Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/inmunología , Espermatogénesis/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Anticuerpos , Bovinos , Hormona Folículo Estimulante/sangre , Hormona Luteinizante/sangre , Masculino , Carne , Ratones , Testosterona/sangre , Vacunación
7.
J Vasc Res ; 52(5): 291-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26890314

RESUMEN

Vascular calcification (VC) is a common feature in patients with type 2 diabetes mellitus, a metabolic disorder that is characterized by hyperglycemia (high blood glucose) in the context of insulin resistance and a relative lack of insulin. Recently, a few studies have indicated that a high concentration of glucose amplifies the osteogenesis of vascular smooth muscle cells (VSMCs). Some previous reports state that endoplasmic reticulum (ER) stress-mediated apoptosis was activated in and contributed to VC. However, whether or not high glucose could induce ER stress-mediated apoptosis and then involve the pathogenesis of VC remains unclear. The purpose of the present study was to investigate whether high blood glucose-induced VC in diabetes mellitus is caused by the ER response and subsequent apoptosis. We examined the effects of high glucose on the ER stress response of VSMCs. High glucose treatment drastically increased the ER stress response in VSMCs. The high glucose-induced osteoblastic differentiation of VSMCs was significantly attenuated by pretreatment with 500 µM of 4-PBA (an ER stress inhibitor) prior to the exposure to high glucose, as evidenced by decreases in the expression of Runx2 and activity of alkaline phosphatase, as well as calcium nodules. These results suggest that high glucose induces the ER stress response and apoptosis, leading to high glucose-elicited VC.


Asunto(s)
Enfermedades de la Aorta/inducido químicamente , Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Glucosa/toxicidad , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Calcificación Vascular/inducido químicamente , Fosfatasa Alcalina/metabolismo , Animales , Aorta/efectos de los fármacos , Aorta/metabolismo , Aorta/patología , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/patología , Osteogénesis/efectos de los fármacos , Fenilbutiratos/farmacología , Ratas Sprague-Dawley , Calcificación Vascular/metabolismo , Calcificación Vascular/patología
8.
Materials (Basel) ; 17(3)2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38591584

RESUMEN

Metal-coated lattice structures hold significant promise for customizing mechanical properties in diverse industrial applications, including the mechanical arms of unmanned aerial vehicles. However, their intricate geometries pose computational challenges, resulting in time-intensive and costly numerical evaluations. This study introduces a parameterization-based multiscale method to analyze body-centered cubic lattice structures with metal coatings. We establish the validity and precision of our proposed method with a comparative analysis of numerical results at the Representative Volume Element (RVE) scale and experimental findings, specifically addressing both elastic tensile and bending stiffness. Furthermore, we showcase the method's accuracy in interpreting the bending stiffness of coated lattice structures using a homogenized material-based solid model, underscoring its effectiveness in predicting the elastic properties of such structures. In exploring the mechanical characterization of coated lattice structures, we unveil positive correlations between elastic tensile stiffness and both coating thickness and strut diameter. Additionally, the metal coating significantly enhances the structural elastic bending stiffness multiple times over. The diverse failure patterns observed in coated lattices under tensile and bending loads primarily stem from varied loading-induced stress states rather than external factors. This work not only mitigates computational challenges but also successfully bridges the gap between mesoscale RVE mechanical properties and those at the global structural scale.

9.
Materials (Basel) ; 17(6)2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38541468

RESUMEN

Lattice materials are widely used in industries due to their designable capabilities of specific stiffness and energy absorption. However, evaluating the mechanical response of macroscopic lattice structures can be computationally expensive. Homogenization-based multi-scale analysis offers an efficient approach to address this issue. To achieve a simpler, while precise, homogenization, the authors proposed an equidistant segmentation (ES) method for the measurement of the effective shear modulus. In this method, the periodic boundary conditions (PBCs) are approximated by constraining the lateral displacement of nodes between parallel layers of periodic cells. The validations were applied to three typical lattice topologies: body-centered cubic (BCC) lattices, gyroid-, and primitive-triply periodic minimal surface (TPMS) lattices, to predict and compare their anti-vibration capacities. The results demonstrated the rationality and the promising precision of the multi-scale-based equivalent modal analysis through the proposed method and that it eliminated the geometric limitation of lattices with diverse frameworks. Overall, a higher anti-vibration capacity of TPMS was observed. In the study, the authors examined the influence of the relative densities on the balance between the anti-vibration capacity and loading capacity (per unit mass) of the TPMS topologies. Specifically, the unit mass of the TPMS with lower relative densities was able to resist higher frequencies, and the structures were dominated by the anti-vibration capacity. In contrast, a higher relative density is better when emphasizing the loading capacity. These findings may provide notable references to the designers and inform the selection of lattice materials for various industrial applications.

10.
Transplant Rev (Orlando) ; 38(2): 100841, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38518424

RESUMEN

Rat orthotopic liver transplantation (ROLT) serves as an ideal animal model and has gained popularity in addressing complications and perioperative treatments related to clinical liver transplantation. Through extensive research on ROLT model construction, the conventional "two-cuff" method has gradually become established. However, traditional methods still present challenges including limited visual field during vascular suturing, vascular torsion, biliary tract injuries, and prolonged anhepatic periods. Consequently, this paper aims to review the latest advancements and various techniques in this field, providing a valuable reference for individuals interested in constructing ROLT models.


Asunto(s)
Trasplante de Hígado , Humanos , Ratas , Animales , Trasplante de Hígado/métodos , Modelos Animales , Anastomosis Quirúrgica
11.
Anal Chim Acta ; 1308: 342575, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38740448

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a prevalent neurodegenerative disease with no effective treatment. Efficient and rapid detection plays a crucial role in mitigating and managing AD progression. Deep learning-assisted smartphone-based microfluidic paper analysis devices (µPADs) offer the advantages of low cost, good sensitivity, and rapid detection, providing a strategic pathway to address large-scale disease screening in resource-limited areas. However, existing smartphone-based detection platforms usually rely on large devices or cloud servers for data transfer and processing. Additionally, the implementation of automated colorimetric enzyme-linked immunoassay (c-ELISA) on µPADs can further facilitate the realization of smartphone µPADs platforms for efficient disease detection. RESULTS: This paper introduces a new deep learning-assisted offline smartphone platform for early AD screening, offering rapid disease detection in low-resource areas. The proposed platform features a simple mechanical rotating structure controlled by a smartphone, enabling fully automated c-ELISA on µPADs. Our platform successfully applied sandwich c-ELISA for detecting the ß-amyloid peptide 1-42 (Aß 1-42, a crucial AD biomarker) and demonstrated its efficacy in 38 artificial plasma samples (healthy: 19, unhealthy: 19, N = 6). Moreover, we employed the YOLOv5 deep learning model and achieved an impressive 97 % accuracy on a dataset of 1824 images, which is 10.16 % higher than the traditional method of curve-fitting results. The trained YOLOv5 model was seamlessly integrated into the smartphone using the NCNN (Tencent's Neural Network Inference Framework), enabling deep learning-assisted offline detection. A user-friendly smartphone application was developed to control the entire process, realizing a streamlined "samples in, answers out" approach. SIGNIFICANCE: This deep learning-assisted, low-cost, user-friendly, highly stable, and rapid-response automated offline smartphone-based detection platform represents a good advancement in point-of-care testing (POCT). Moreover, our platform provides a feasible approach for efficient AD detection by examining the level of Aß 1-42, particularly in areas with low resources and limited communication infrastructure.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Biomarcadores , Ensayo de Inmunoadsorción Enzimática , Papel , Teléfono Inteligente , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/sangre , Humanos , Biomarcadores/sangre , Biomarcadores/análisis , Péptidos beta-Amiloides/análisis , Péptidos beta-Amiloides/sangre , Fragmentos de Péptidos/sangre , Fragmentos de Péptidos/análisis , Dispositivos Laboratorio en un Chip , Aprendizaje Profundo , Automatización , Técnicas Analíticas Microfluídicas/instrumentación
12.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167336, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38972433

RESUMEN

Epiregulin (EREG) is a member of the epidermal growth factor (EGF) family. An increasing body of evidence has demonstrated the pivotal role of EREG in the pathogenesis and progression of various malignancies. However, the clinical significance and biological role of EREG in pancreatic ductal adenocarcinoma (PDAC) have yet to be fully elucidated. We found that EREG is highly expressed in PDAC tissues compared with paracancerous tissues through public databases and clinical samples. High EREG expression predicted worse overall survival (OS) and recurrence-free survival (RFS) in patients with PDAC. Multivariate analysis revealed that EREG can serve as an independent prognostic indicator. In addition, EREG silencing inhibited PDAC cell proliferation, migration, progression, altered cell cycle, facilitated apoptosis in vitro and suppressed tumor growth in vivo. Conversely, EREG overexpression facilitated the proliferation, migration, and invasion in PaTu-8988 t cell. Through transcriptome sequencing and experimental verification, we found EREG mediates PDAC tumorigenesis through ERK/p38 MAPK signaling pathway. Moreover, we found EREG expression is closely related to PD-L1 expression in PDAC tissues and cells. Therefore, EREG is expected to be a prospective prognostic and therapeutic marker for PDAC.

13.
Cell Rep ; 43(6): 114277, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38805397

RESUMEN

Affective empathy enables social mammals to learn and transfer emotion to conspecifics, but an understanding of the neural circuitry and genetics underlying affective empathy is still very limited. Here, using the naive observational fear between cagemates as a paradigm similar to human affective empathy and chemo/optogenetic neuroactivity manipulation in mouse brain, we investigate the roles of multiple brain regions in mouse affective empathy. Remarkably, two neural circuits originating from the ventral hippocampus, previously unknown to function in empathy, are revealed to regulate naive observational fear. One is from ventral hippocampal pyramidal neurons to lateral septum GABAergic neurons, and the other is from ventral hippocampus pyramidal neurons to nucleus accumbens dopamine-receptor-expressing neurons. Furthermore, we identify the naive observational-fear-encoding neurons in the ventral hippocampus. Our findings highlight the potentially diverse regulatory pathways of empathy in social animals, shedding light on the mechanisms underlying empathy circuity and its disorders.


Asunto(s)
Empatía , Hipocampo , Animales , Empatía/fisiología , Hipocampo/fisiología , Hipocampo/metabolismo , Ratones , Masculino , Miedo/fisiología , Ratones Endogámicos C57BL , Neuronas GABAérgicas/metabolismo , Neuronas GABAérgicas/fisiología , Células Piramidales/fisiología , Células Piramidales/metabolismo , Vías Nerviosas/fisiología , Núcleo Accumbens/fisiología
14.
Chem Asian J ; : e202400413, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38822713

RESUMEN

Reaction of a P/N/S hybrid ligand dpppyatc (N,N-bis((diphenylphosphaneyl)methyl)-N-(pyridin-2-yl)-amino-thiocarbamide) with Au(tht)Cl (tht=tetrahydrothiophene) and [Cu(MeCN)4]BF4 afforded cluster complex [Au2Cu(dpppyatc)2](BF4)2Cl (1). Upon excitation at 480 nm, 1 emitted orange phosphorescence at 646 nm, which was red-shifted to ~698 nm selectively in the presence of ammonia or amine vapor. This chromic photoluminescent response toward ammonia was sensitive and reversible. Complex1 could detect ammonia in aqueous solution down to concentrations of 2 ppm (w/w).

15.
Heliyon ; 9(3): e14448, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36967951

RESUMEN

Reliable extreme lightweight is the pursuit in many high-end manufacturing areas. Aided by additive manufacturing (AM), lattice material has become a promising candidate for lightweight optimization. Configuration of lattice units at the material level and the distribution of lattice units at the structure level are the two main research directions recently. This paper proposes a generative strategy for lattice infilling optimization using organic strut-based lattices. A sphere packing algorithm driven by von Mises stress fields determines the lattice distribution density. Two typical configurations, Voronoi polygons and Delaunay triangles, are adopted to constitute the frames, respectively. Based on finite element analysis, a simplified truss model is utilized to evaluate the lattice distribution in terms of mechanical properties. Optimization parameters, including node number, mapping gradient, and the range of varying circle size, are investigated through the genetic algorithm (GA). Multiple feasible solutions are obtained for further solidification modelling. To avoid the stress concentration, the organic strut-based lattice units are created by the iso-surface modelling method. The effectiveness of the proposed generative approach is illustrated through a classical 3-point bending beam. The stiffness of the optimized structure, verified through experimental testing, has increased 80% over the one using the traditional uniform body center cubic (BCC) lattice distribution.

16.
Materials (Basel) ; 16(21)2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37959490

RESUMEN

Based on the lightweight characteristics of automotive energy absorption boxes and the requirement of good energy absorption effect, this article first applies the node-enhanced body centered cubic (NBCC) lattice structure to the inner core design of automotive energy absorption boxes. The gradient study of the NBCC lattice structure was carried out using a drop hammer impact and split Hopkinson pressure bar (SHPB). The results indicate that gradient lattice structures have advantages in energy absorption, but there are differences under different gradient strategies. When the impact is not sufficient to compact the structure, the vertical rod diameter gradient node-enhanced lattice structure (RGNBCC) can absorb more energy and improve energy absorption performance by 25%. The vertical height gradient node-enhanced lattice structure (HGNBCC) is more suitable for high-speed impact conditions. Based on the advantages of the RGNBCC in resisting low-speed impacts, it is applied to the inner core design of automotive energy absorption boxes and optimized using multi-objective optimization methods. The optimization results show that the maximum peak impact force is reduced by 45.6% and the specific energy absorption is increased by 30.4%.

17.
Bioresour Technol ; 369: 128461, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36503086

RESUMEN

Solid-state anaerobic digestion (SSAD) is vulnerable to excess volatile fatty acids (VFA), mainly acetate and propionate. The co-effects of VFAs and microbial dynamics under VFA accumulation were investigated in SSAD of pig manure and corn straw. Adding 2 and 4 mg/g acetate or propionate caused initial increases in total VFAs, followed by decreases after day 6, resulting in 'mild' VFA accumulation, while adding 6 mg/g caused similarly increased VFAs, but with no subsequent decrease, causing 'severe' VFA accumulation and poor methanation performance. Mild propionate accumulation promoted acetate consumption, whereas acetate accumulation inhibited propionate degradation by affecting crucial redox reactions. Under severe VFA accumulation, hydrolysis and acidification mainly conducted by acid-tolerant Clostridium sp. exacerbated VFA inhibition, causing a competition between Methanosarcina and Methanosaeta, and impairments of acetoclastic and hydrogenotrophic methanogenesis and interspecies formate transfer. This study provides new insights into mechanisms of VFA accumulation in SSAD, and its effects on methanogenesis.


Asunto(s)
Microbiota , Propionatos , Animales , Porcinos , Propionatos/metabolismo , Anaerobiosis , Reactores Biológicos , Metano/metabolismo , Ácidos Grasos Volátiles/metabolismo , Acetatos , Redes y Vías Metabólicas
18.
Front Oncol ; 13: 1174999, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38162488

RESUMEN

Objective: To assess the efficacy and safety of camrelizumab plus different targeted drugs in adjuvant therapy after hepatocellular carcinoma (HCC) surgery. Patients and methods: This retrospective cohort study included HCC patients who, after undergoing failed postoperative adjuvant lenvatinib therapy, received intravenous camrelizumab 200 mg every 3 weeks (C group, n = 97), camrelizumab plus oral apatinib 250 mg daily (C+A group, n = 125), camrelizumab plus oral lenvatinib 12 mg daily (for bodyweight ≥60 kg)/lenvatinib 8 mg daily (for bodyweight <60 kg) (C+L group, n = 120), or camrelizumab plus oral sorafenib 400 mg bi-daily (C+S group, n = 114) between October 2020 and October 2021. The outcomes including the objective response rate (ORR) and disease control rate (DCR) were evaluated by RECIST 1.1 and iRECIST. The median progression-free survival (mPFS), median overall survival (mOS), 6-month OS rate, 12-month OS rate, and adverse events were evaluated. Results: As of 31 May 2022 with last follow-up time, the ORR was 17.2% for the C group, 44.6% for the C+A group, 47.9% for the C+L group, and 36.3% for the C+S group. The DCR was 72.0% for the C group, 81.8% for the C+A group, 85.5% for the C+L group, and 77.9% for the C+S group. The mPFS was 11.0 months (10.1-12.8) for the C group, 14.0 months (12.7-16.5) for the C+A group, 18.0 months (16.9-20.1) for the C+L group, and 12.0 months (9.7-14.4) for the C+S group. The mOS was 13.0 months (11.6-15.3) for the C group, 17.0 months (15.8-19.4) for the C+A group, 19.0 months (17.7-20.2) for the C+L group, and 15.0 months (14.1-17.3) for the C+S group. Grade 3 or 4 treatment-related adverse events occurred in 14 patients (14.4%) for the C group, 10 patients (8.0%) for the C+A group, 5 patients (4.2%) for the C+L group, and 11 patients (9.6%) for the C+S group. The most common adverse events were fatigue and transaminitis. Conclusion: Camrelizumab combined with lenvatinib as adjuvant therapy showed promising efficacy and manageable safety in HCC patients. It might be a potential adjuvant therapy or second-line treatment for these patients.

19.
Shock ; 60(3): 385-391, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37548623

RESUMEN

ABSTRACT: Background: Cardiogenic shock complicating acute myocardial infarction (AMICS) remains a high 30-day mortality. Mechanical circulatory support devices are increasingly used in AMICS, but their effects on mortality vary partly because of shock severity. Aims: This study aimed to evaluate the association between intra-aortic balloon pump (IABP) and 30-day mortality in patients with early-stage AMICS. Methods: We retrospectively analyzed patients with ST-segment elevation myocardial infarction (STEMI) based on a multicenter clinical trial (NCT04996901). Patients were stratified by IABP use, and shock severity was classified according to the Society for Cardiovascular Angiography and Interventions (SCAI) SHOCK stages. The primary outcome was 30-day all-cause mortality. The association between IABP and 30-day mortality was evaluated across shock stages using propensity score matching, weighting, and logistic regression. Results: Five thousand three hundred forty-three patients were included, and 299 received IABP. The SCAI SHOCK stage was associated with 30-day mortality (odds ratio [OR], 20.19; 95% confidence interval [CI], 13.60-29.97; P < 0.001). In the 580 matched patients, a significant interaction between IABP and 30-day mortality at different shock stages was observed ( P = 0.005). Intra-aortic balloon pump was associated with lower 30-day mortality among patients with shock stage A/B (5.8% vs. 1.2%; OR, 0.19; 95% CI, 0.03-0.73; P = 0.034) but not stage C/D/E (29.3% vs. 38.1%; OR, 1.49; 95% CI, 0.84-2.65; P = 0.172). These results were confirmed by sensitivity analyses of the weighted cohort. Conclusions: Intra-aortic balloon pump reduced 30-day mortality in patients with early-stage AMICS. The SCAI SHOCK stage provides risk stratification for patients with STEMI and helps identify those who may respond well to IABP.


Asunto(s)
Infarto del Miocardio , Infarto del Miocardio con Elevación del ST , Humanos , Choque Cardiogénico/etiología , Infarto del Miocardio con Elevación del ST/complicaciones , Infarto del Miocardio con Elevación del ST/cirugía , Estudios Retrospectivos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/terapia , Contrapulsador Intraaórtico , Resultado del Tratamiento
20.
Biol Trace Elem Res ; 200(3): 1156-1163, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33899168

RESUMEN

Copper (Cu) is an essential trace element, but excessive Cu intake can induce poor performance and Cu poisoning and result in various health problems. Cu and molybdenum (Mo) antagonize each other in vivo. Therefore, Mo can reduce the absorption and utilization of Cu. The aims of this study were to investigate the impacts of Mo fertilization on antioxidant capacity of grazing Nanjiang brown goat on Cu-polluted meadow and explore the control methods of Cu pollution in natural pasture. Fertilization and grazing experiments were carried out in Liangshan Yi Nationality Prefecture of the Western Sichuan Plateau, Sichuan Province, Southwest China. Cu-polluted meadows of 12 hm2 were fenced, and randomly divided into two groups (3 replications/group, 2 hm2/replication), control group and treatment group, fed with basic diets supplemented with 0 and 3 kg Mo/hm2 [ammonium molybdate tetrahydrate, (NH4)6Mo7O24·4H2O], respectively. In the current study, 36 healthy Nanjiang brown goats (1 year old, 32.8 ± 1.1 kg) were randomly divided into two groups (3 replications/group, 6 goats/replication) and assigned to the experimental pastures. The grazing experiment lasted for 60 days. The results showed that the concentration of Mo in soil in treatment group was 96.28 mg/kg, far exceeding the normal levels. At days 30 and 60, the levels of Hb, RBC, and PCV in blood in treatment group and the activities of serum SOD, GSH-Px, T-AOC, CAT, and Cp were higher than those in control group (P < 0.01). The MDA content in treatment group was lower than that in control group (P < 0.01). The contents of Cu in blood and liver in treatment goats were lower than those in control animals (P < 0.01). The contents of Zn and Mo in blood and liver in treatment goats were higher than those in control animals (P < 0.01). The Mn content in liver in treatment group was higher than that in control animals (P < 0.01). These results indicated that fertilization of (NH4)6Mo7O24 not only markedly influenced the mineral contents in blood and liver, but also extremely improved antioxidant capacity of grazing Nanjiang brown goat from fertilized pastures and relieved the damage caused by Cu pollution.


Asunto(s)
Antioxidantes , Molibdeno , Animales , Cobre , Fertilización , Cabras
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