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1.
Nature ; 623(7985): 95-99, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37914947

RESUMO

Seismic images of Earth's interior have revealed two continent-sized anomalies with low seismic velocities, known as the large low-velocity provinces (LLVPs), in the lowermost mantle1. The LLVPs are often interpreted as intrinsically dense heterogeneities that are compositionally distinct from the surrounding mantle2. Here we show that LLVPs may represent buried relics of Theia mantle material (TMM) that was preserved in proto-Earth's mantle after the Moon-forming giant impact3. Our canonical giant-impact simulations show that a fraction of Theia's mantle could have been delivered to proto-Earth's solid lower mantle. We find that TMM is intrinsically 2.0-3.5% denser than proto-Earth's mantle based on models of Theia's mantle and the observed higher FeO content of the Moon. Our mantle convection models show that dense TMM blobs with a size of tens of kilometres after the impact can later sink and accumulate into LLVP-like thermochemical piles atop Earth's core and survive to the present day. The LLVPs may, thus, be a natural consequence of the Moon-forming giant impact. Because giant impacts are common at the end stages of planet accretion, similar mantle heterogeneities caused by impacts may also exist in the interiors of other planetary bodies.

2.
Carcinogenesis ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829328

RESUMO

Cancer cells exhibit heterogenous metastatic potential, and high metastatic subclones can enhance metastatic potential of low metastatic subclones by transmitting some factors. Exosomal miRNAs play a pivotal role in the crosstalk of heterogenous metastatic subclones. This study discovered that miR-20a-3p was upregulated in colorectal adenocarcinoma (CRA), correlated with metastasis, and potentially served as a prognostic indicator for CRA. miR-20a-3p could promote the proliferation, migration and invasion of CRA cells. Interestingly, high metastatic CRA cells could promote malignant phenotypes of low metastatic CRA cells by transmitting exosomal miR-20a-3p. Mechanically, miR-20a-3p could inhibit NF1, thereby activate the RAS-mediated mitogen-activated protein kinases (MAPK) signaling pathway to drive the metastasis of CRA. In summary, our study provided the evidence that colorectal cancer cells with high metastatic potential drive metastasis by transmitting exosomal miR-20a-3p through modulating NF1/MAPK pathway.

3.
Anal Chem ; 96(29): 11862-11868, 2024 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-38989925

RESUMO

Current molecular logic gates are predominantly focused on the qualitative assessment of target presence, which has certain limitations in scenarios requiring quantitative assessment, such as chemical contaminant monitoring. To bridge this gap, we have developed a novel DNA logic gate featuring a tunable threshold, specifically tailored to the limits of contaminants. At the core of this logic gate is a DNA-gold nanoparticle (AuNP) hybrid film that incorporates aptamer sequences to selectively bind to acetamiprid (ACE) and atrazine (ATR). Upon interaction with these contaminants, the film degrades, releasing AuNPs that, in the presence of Hg2+, catalyze the oxidation of TMB, resulting in a visible blue coloration on test paper. This aptamer-enabled process effectively establishes an OR logic gate, with ACE and ATR as inputs and the appearance of blue color as the output. A key innovation of our system is its tunable input threshold. By adjusting the concentration of Hg2+, we can fine-tune the color mutation points to match the input threshold to predefined limits, such as Maximum Residue Limits (MRLs). This alignment allows semiquantitative assessment of contaminant levels, providing intuitive visual feedback of contaminant exceedance. Validation experiments with spiked samples confirm its accuracy and reliability by closely matching HPLC results. Therefore, our colorimetric DNA logic gate is emerging as a promising tool for easy and semiquantitative monitoring of chemical contaminants across diverse applications.


Assuntos
Atrazina , Colorimetria , DNA , Ouro , Nanopartículas Metálicas , Neonicotinoides , Nanopartículas Metálicas/química , Ouro/química , Atrazina/análise , Atrazina/química , Neonicotinoides/análise , Neonicotinoides/química , DNA/química , Aptâmeros de Nucleotídeos/química , Computadores Moleculares , Mercúrio/análise , Mercúrio/química
4.
Opt Express ; 32(2): 2804-2816, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297800

RESUMO

Antimonide superlattice materials with tunable energy bands, high electron mobility, and easy attainment of good uniformity in large-area materials, are considered to be the material of choice for third-generation infrared photodetectors. Based on energy band engineering, this paper designs a series of long-wave infrared(LWIR) to very-long-wave infrared(VLWIR) photodetectors by employing M-structure superlattice(M-SL) as both absorber layer and barrier layer. The photodetectors' performances at different temperatures are simulated in this manuscript. At 77K, while minimizing the lattice mismatch, effectively suppresses the dark current of the device which can be as low as 1× 10-8A/cm2, with a quantum efficiency reaching 20.85% and normalized detectivity achieves 4.78×1011 cm·Hz1/2/W for LWIR photodetector with a cutoff wavelength of 11.1 µm. For the VLWIR photodetector with a cutoff wavelength of 16.7 µm, the corresponding figures are 1×10-6A/cm2, 16.77% and 3.09×1010 cm·Hz1/2/W, respectively.

5.
Environ Res ; 251(Pt 2): 118714, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518916

RESUMO

Disposal and recycling of heavy metal-enriched biomass is the key to measure the success of phytoremediation. This study employed innovative approach to use Aspergillus niger (A. niger) for the treatment of Cd-contaminated Helianthus annuus L. (sunflower) stalk after phytoremediation. Single-factor results showed that the removal of Cd at an initial pH of 3 was superior to sucrose and inoculation amount. 67.67% of Cd was removed by A. niger leaching system after 11 days based on response surface methodology optimum conditions (sucrose: 76.266 g L-1; inoculation amount: 10%; initial pH: 3), while the concentrations of nitrogen, phosphorus and potassium (N, P and K) of sunflower stalk were unaffected. While physicochemical pretreatment effectively enhanced the bioleaching efficiency, it also resulted in significant loss of P and K elements, thereby reducing the value of biomass for recycling and utilization. Therefore, the direct A. niger leaching method without pretreatment is more advantageous for the safe treatment and recycling of Cd-contaminated sunflower stalks.


Assuntos
Aspergillus niger , Biodegradação Ambiental , Cádmio , Helianthus , Helianthus/metabolismo , Aspergillus niger/metabolismo , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Biomassa
6.
BMC Musculoskelet Disord ; 25(1): 213, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481217

RESUMO

Osteoporosis is caused by the imbalance of osteoblasts and osteoclasts. The regulatory mechanisms of differentially expressed genes (DEGs) in pathogenesis of osteoporosis are of significant and needed to be further investigated. GSE100609 dataset downloaded from Gene Expression Omnibus (GEO) database was used to identified DEGs in osteoporosis patients. KEGG analysis was conducted to demonstrate signaling pathways related to enriched genes. Osteoporosis patients and the human mesenchymal stem cells (hMSCs) were obtained for in vivo and in vitro resaerch. Lentivirus construction and viral infection was used to knockdown genes. mRNA expression and protein expression were detected via qRT-PCR and western blot assay separately. Alkaline phosphatase (ALP) activity detection, alizarin Red S (ARS) staining, and expression of bone morphogenetic protein 2 (BMP2), osteocalcin (OCN) and Osterix were evaluated to determine osteoblast differentiation capacity. UL-16 binding protein 1 (ULBP1) gene was upregulated in osteoporosis and downregulated in differentiated hMSCs. Knockdown of ULBP1 increased ALP activity, mineralization ability evaluated by ARS staining, expression of BMP2, OCN and Osterix in differentiated hMSCs. Furthermore, rescue experiment demonstrated that suppressed ULBP1 boosted osteoblast differentiation by activating TNF-ß signaling pathway. Knockdown of ULBP1 gene could promoted osteoblast differentiation by activating TNF-ß signaling pathway in differentiated hMSCs. ULBP1 may be a the Achilles' heel of osteoporosis, and suppression of ULBP1 could be a promising treatment for osteoporosis.


Assuntos
Células-Tronco Mesenquimais , Osteoporose , Humanos , Proteínas de Transporte/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Linfotoxina-alfa/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteogênese/genética , Osteoporose/genética , Proteína Smad2/metabolismo
7.
Int Endod J ; 57(9): 1315-1325, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38923421

RESUMO

AIM: Autophagy is involved in human apical periodontitis (AP). However, it is not clear whether autophagy is protective or destructive in bone loss via the receptor activator of nuclear factor-κB ligand (RANKL)/RANK/osteoprotegerin (OPG) axis. This study aimed to investigate the involvement of autophagy via the RANKL/RANK/OPG axis during the development of AP in an experimental rat model. METHODOLOGY: Twenty-four female Sprague-Dawley rats were divided into control, experimental AP (EAP) + saline, and EAP + 3-methyladenine (An autophagy inhibitor, 3-MA) groups. The control group did not receive any treatment. The EAP + saline group and the EAP + 3-MA group received intraperitoneal injections of saline and 3-MA, respectively, starting 1 week after the pulp was exposed. Specimens were collected for microcomputed tomography (micro-CT) scanning, histological processing, and immunostaining to examine the expression of light chain 3 beta (LC3B), RANK, RANKL, and OPG. Data were analysed using one-way analysis of variance (p < .05). RESULTS: Micro-CT showed greater bone loss in the EAP + 3-MA group than in the EAP + saline group, indicated by an elevated trabecular space (Tb.Sp) (p < .05). Inflammatory cell infiltration was observed in the EAP + saline and EAP + 3-MA groups. Compared with EAP + saline group, the EAP + 3-MA group showed weaker expression of LC3B (p < .01) and OPG (p < .05), more intense expression of RANK (p < .01) and RANKL (p < .01), and a higher RANKL/OPG ratio (p < .05). CONCLUSION: Autophagy may exert a protective effect against AP by regulating the RANKL/RANK/OPG axis, thereby inhibiting excessive bone loss.


Assuntos
Perda do Osso Alveolar , Autofagia , Modelos Animais de Doenças , Osteoprotegerina , Periodontite Periapical , Ligante RANK , Ratos Sprague-Dawley , Receptor Ativador de Fator Nuclear kappa-B , Microtomografia por Raio-X , Animais , Feminino , Ratos , Adenina/análogos & derivados , Adenina/farmacologia , Perda do Osso Alveolar/metabolismo , Perda do Osso Alveolar/patologia , Osteoprotegerina/metabolismo , Periodontite Periapical/metabolismo , Periodontite Periapical/patologia , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo
8.
BMC Med Educ ; 24(1): 499, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705981

RESUMO

AIMS: This study aimed to investigate the feasibility and effectiveness of utilizing three-dimensional (3D) printing technology in the simulation teaching of congenital malformations. METHODS: We conducted a comparative analysis between an experimental group that received traditional teaching supplemented with 3D printing model demonstrations and hands-on model operation, and a control group that received traditional teaching methods. Various parameters, including classroom interest, classroom interaction, learning enthusiasm, disease awareness, teaching satisfaction, and independent operation confidence, were assessed, along with theoretical and practical tests. RESULTS: The results showed no significant difference in theoretical test scores between the two groups (91.92 ± 15.04 vs. 89.44 ± 14.89), but the practical test revealed a significantly higher number of qualified trainees in the experimental group compared to the control group (23 vs. 8). In terms of classroom engagement, both groups exhibited similar levels of interest (8.08 ± 1.52 vs. 8.74 ± 0.984), classroom interaction (7.88 ± 1.97 vs. 8.7 ± 1.33), learning enthusiasm (8.81 ± 1.021 vs. 8.52 ± 1.189), and disease awareness (8.58 ± 0.99 vs. 8.58 ± 0.99). However, the experimental group demonstrated significantly higher teaching satisfaction (8.81 ± 1.06 vs. 9.19 ± 0.96) and greater operation confidence (7.67 ± 2.56 vs. 5.5 ± 2.79) than the control group. CONCLUSION: 3D printing technology can be effectively utilized to create surgical teaching models, enhancing the confidence of standardized training doctors and improving teaching outcomes.


Assuntos
Anormalidades Congênitas , Estudos de Viabilidade , Impressão Tridimensional , Treinamento por Simulação , Humanos , Modelos Anatômicos , Avaliação Educacional , Masculino , Feminino
9.
Pediatr Surg Int ; 40(1): 94, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551785

RESUMO

OBJECTIVE: To evaluate whether infants with prenatal diagnosis of meconium peritonitis (MP) have a poorer prognosis. METHODS: A retrospective analysis of data from infants treated with surgery from January 2008 to December 2020 was conducted. The patients were divided into prenatal diagnosis group and postnatal diagnosis group based on the timing of diagnosis. The intraoperative and postoperative parameters of the two groups of patients were compared. RESULTS: A total of 71 cases of MP were included in the study, with 48 cases in the prenatal diagnosis group and 23 cases in the postnatal diagnosis group. The comparison of preoperative indicators between the two groups of patients showed no statistically significant differences in baseline (p > 0.05). Intraoperative indicators, including blood loss, anastomosis, retained intestinal tube length and excised intestinal tube length, showed no statistically significant differences between the two groups (p > 0.05). However, the postnatal diagnosis group had a significantly shorter operation time than the prenatal diagnosis group (p < 0.05). Postoperative indicators, including fasting time, albumin usage, complications, and abandonment or mortality rates, show no difference (p > 0.05). Nevertheless, the postnatal diagnosis group exhibited significantly shorter hospital stay and time to first bowel movement compared to the prenatal diagnosis group (p < 0.05). CONCLUSION: Prenatal diagnosis of meconium peritonitis is associated with increased surgical complexity, prolonged hospital stay, and delayed recovery of intestinal function. However, there is no evidence of higher mortality or more complications compared to infants diagnosed postnatally, and there is no significant difference in long-term prognosis.


Assuntos
Doenças do Recém-Nascido , Peritonite , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Mecônio , Estudos Retrospectivos , Ultrassonografia Pré-Natal/efeitos adversos , Idade Gestacional , Diagnóstico Pré-Natal , Peritonite/diagnóstico , Peritonite/cirurgia
10.
Perfusion ; : 2676591241237133, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39175255

RESUMO

Background: Extracorporeal life support echniques as an Adjunct to Advanced Cardiac Life Support is usually suitable for complex heart surgery such as cardiopulmonary bypass (CPB). Cerebral perfusion is a clinically feasible neuroprotective strategy; however, the lack of a reliable small animal model.Methods: Based on the rat model of ECLS we evaluate the effects of ECLS-CP using HE staining, Nissl staining, TUNEL staining and ELISA.Result: We found that ECLS combined with the cerebral perfusion model did not cause brain injury and immune inflammation. There was no difference between the two by a left carotid artery or right carotid artery CP.Conclusion: These experimental results can provide the experimental basis for selecting blood vessels for ECLS patients and clinical CP to offers a trustworthy animal model for future exploration of applying brain perfusion strategies during ECLS-CP.

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