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1.
BMC Pregnancy Childbirth ; 24(1): 338, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702634

RESUMEN

OBJECTIVE: This study aims to perform a prenatal genetic diagnosis of a high-risk fetus with trisomy 7 identified by noninvasive prenatal testing (NIPT) and to evaluate the efficacy of different genetic testing techniques for prenatal diagnosis of trisomy mosaicism. METHODS: For prenatal diagnosis of a pregnant woman with a high risk of trisomy 7 suggested by NIPT, karyotyping and chromosomal microarray analysis (CMA) were performed on an amniotic fluid sample. Low-depth whole-genome copy number variation sequencing (CNV-seq) and fluorescence in situ hybridization (FISH) were used to clarify the results further. In addition, methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) was performed to analyze the possibility of uniparental disomy(UPD). RESULTS: Amniotic fluid karyotype analysis revealed a 46, XX result. Approximately 20% mosaic trisomy 7 was detected according to the CMA result. About 16% and 4% of mosaicism was detected by CNV-seq and FISH, respectively. MS-MLPA showed no methylation abnormalities. The fetal ultrasound did not show any detectable abnormalities except for mild intrauterine growth retardation seen at 39 weeks of gestation. After receiving genetic counseling, the expectant mother decided to continue the pregnancy, and follow-up within three months of delivery was normal. CONCLUSION: In high-risk NIPT diagnosis, a combination of cytogenetic and molecular genetic techniques proves fruitful in detecting low-level mosaicism. Furthermore, the exclusion of UPD on chromosome 7 remains crucial when NIPT indicates a positive prenatal diagnosis of trisomy 7.


Asunto(s)
Cromosomas Humanos Par 7 , Variaciones en el Número de Copia de ADN , Hibridación Fluorescente in Situ , Cariotipificación , Mosaicismo , Trisomía , Disomía Uniparental , Humanos , Femenino , Mosaicismo/embriología , Embarazo , Hibridación Fluorescente in Situ/métodos , Cromosomas Humanos Par 7/genética , Trisomía/diagnóstico , Trisomía/genética , Cariotipificación/métodos , Adulto , Disomía Uniparental/diagnóstico , Disomía Uniparental/genética , Diagnóstico Prenatal/métodos , Análisis por Micromatrices/métodos , Pruebas Prenatales no Invasivas/métodos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Líquido Amniótico
2.
bioRxiv ; 2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38559208

RESUMEN

Caloric restriction (CR) is known to extend lifespan across different species and holds great promise for preventing human age-onset pathologies. However, two major challenges exist. First, despite extensive research, the mechanisms of lifespan extension in response to CR remain elusive. Second, genetic differences causing variations in response to CR and genetic factors contributing to variability of CR response on lifespan are largely unknown. Here, we took advantage of natural genetic variation across 46 diploid wild yeast isolates of Saccharomyces species and the lifespan variation under CR conditions to uncover the molecular factors associated with CR response types. We identified genes and metabolic pathways differentially regulated in CR-responsive versus non-responsive strains. Our analysis revealed that altered mitochondrial function and activation of GCN4-mediated environmental stress response are inevitably linked to lifespan variation in response to CR and a unique mitochondrial metabolite might be utilized as a predictive marker for CR response rate. In sum, our data suggests that the effects of CR on longevity may not be universal, even among closely related species or strains of a single species. Since mitochondrial mediated signaling pathways are evolutionarily conserved, the dissection of related genetic pathways will be relevant to understanding the mechanism by which CR elicits its longevity effect.

3.
Front Oncol ; 14: 1360557, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38496755

RESUMEN

Background: While hemangiomas are the most commonly occurring benign vascular tumors, their occurrence in the gastrointestinal system is rare. This case report presents a unique instance of small intestinal hemangioma in a pediatric patient. Case description: A 21-month-old girl was admitted to the hospital with a history of "recurrent blood in the stool for one year and anemia for five months." Upon evaluation at our facility, abdominal color ultrasound and enhanced CT scans revealed a protruding mass in the wall of the small intestine, leading to a preliminary diagnosis of small intestinal hemangioma. Subsequent single-site umbilical laparoscopic exploration identified a tumor measuring approximately 6cm×2.5cm×1.2cm on the jejunum wall. Consequently, segmental resection of the intestine was performed, and the postoperative pathological diagnosis confirmed cavernous hemangioma. Conclusion: Small intestinal hemangiomas, particularly in pediatric patients, are exceptionally rare and challenging to diagnose as the cause of gastrointestinal bleeding prior to surgery. Hence, small intestinal hemangiomas should be considered in such cases. Laparoscopic surgical resection emerges as the optimal approach for addressing small intestinal hemangiomas.

4.
Congenit Anom (Kyoto) ; 64(3): 99-106, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38454888

RESUMEN

The phenotype of SCA patients are diversities, make prenatal counseling and parental decision-making following the prenatal diagnosis of SCA more complicated and challenging. NIPT has higher sensitivity and specificity in screening trisomy 21 syndrome, but the effectiveness of NIPT in detecting SCA is still controversial. This study is a large-scale retrospective cohort of positive SCA screened from unselected singleton pregnancies by non-invasive prenatal testing (NIPT) from a single prenatal center of a tertiary hospital. Clinical information, indications, diagnostic results, ultrasound findings, pregnancy determinations, and follow-up were reviewed and analyzed. 596 cases of SCA positive were screened out of 122 453, giving a positive detection rate of 0.49%. 510 cases (85.6%) conducted with amniocentesis to detect fetal chromosome, of which 236 were confirmed as true positive of SCA with PPV of 46.3% (236/510). Of the 236 cases confirmed as true positive SCA, 114 cases (48.3%)chose to terminate the pregnancy (93.0%, 65.3%, 15.4% and 10.9% for 45,X, 47,XXY, 47,XXX and 47,XYY, respectively), 122 cases (51.7%) elected to continue the pregnancy. In conclusions, NIPT as a first-tier routine method for screening autosomal aneuploidies, also could play an important role in screening SCA. Low-risk pregnant women are the main indication for the detection of SCA as NIPT test provides to non-selective population. For 47,XXX and 47,XYY with mild phenotype, couples would like to continue the pregnancy. But for 45,X and 47,XXY, parents apt to terminate pregnancy no matter ultrasound abnormalities were found or not.


Asunto(s)
Aneuploidia , Diagnóstico Prenatal , Aberraciones Cromosómicas Sexuales , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Adulto , Diagnóstico Prenatal/métodos , Pruebas Prenatales no Invasivas/métodos , Estudios de Seguimiento , Amniocentesis
5.
Drug Resist Updat ; 73: 101060, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309140

RESUMEN

Cancer lactate metabolic reprogramming induces an elevated level of extracellular lactate and H+, leading to an acidic immunosuppressive tumor microenvironment (TEM). High lactic acid level may affect the metabolic programs of various cells that comprise an antitumor immune response, therefore, restricting immune-mediated tumor destruction, and leading to therapeutic resistance and unsatisfactory prognosis. Here, we report a metal-phenolic coordination-based nanocomplex loaded with a natural polyphenol galloflavin, which inhibits the function of lactate dehydrogenase, reducing the production of lactic acid, and alleviating the acidic immunosuppressive TME. Besides, the co-entrapped natural polyphenol carnosic acid and the synthetic PEG-Ce6 polyphenol derivative (serving as a photosensitizer) could induce immunogenic cancer cell death upon laser irradiation, which further activates immune system and promotes immune cell recruitment and infiltration in tumor tissues. We demonstrated that this nanocomplex-based combinational therapy could reshape the TME and elicit immune responses in a murine breast cancer model, which provides a promising strategy to enhance the therapeutic efficiency of drug-resistant breast cancer.


Asunto(s)
Neoplasias de la Mama , Neoplasias , Humanos , Animales , Ratones , Femenino , Ácido Láctico , Polifenoles/farmacología , Reprogramación Metabólica , Neoplasias/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Fenoles , Microambiente Tumoral
6.
Soft Matter ; 20(9): 2017-2023, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38334445

RESUMEN

Surgical adhesives play a crucial role in tissue integration and repair, yet their application in wet conditions has been severely limited by inadequate adhesive strength and subpar biocompatibility. Furthermore, tissue adhesives have rarely been reported in cartilage tissue repair. In this study, a three-armed dopamine-modified hyaluronic acid derivative adhesive was prepared to function as a bio-inspired adhesive in moist environments. To meet the clinical requirements for cartilage tissue adhesion, we studied its chemical structure, including microscopic morphology, adhesion properties with materials and tissues, in vivo degradation rules, and biological evaluation. The OGMHA8-DOPA adhesive with the optimal aldehyde substitution degree and dopamine-grafting rate was determined by analyzing the experimental conditions. SEM results revealed that the cartilage tissue adhered to a porous interconnected structure. The excellent biocompatibility of the material not only facilitated chondrocyte adhesion but also supported their proliferation on its surface. Animal experiments have demonstrated that this material has no observable inflammatory response or incidence of fibrous capsule formation. The degradation timeline of the material extends beyond the duration of two weeks. The dopamine-modified adhesive exhibited a tight interfacial binding force between the biomaterial and cartilage tissue and excellent biocompatibility in watery tissue, revealing its potential for application in cartilage tissue repair and minimally invasive surgery.


Asunto(s)
Adhesivos , Materiales Biocompatibles , Animales , Materiales Biocompatibles/farmacología , Adhesivos/química , Dopamina/química , Cartílago , Condrocitos
7.
ACS Appl Mater Interfaces ; 16(9): 11336-11348, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38407027

RESUMEN

Articular cartilage injury is a common disease in clinical medicine. Because of its special physiological structure and lack of blood, lymph, and nerves, its ability to regenerate once damaged is very limited. In this study, we designed and synthesized a series of self- and coassembled cartilage-inducing functional peptide molecules and constructed a coassembled functional peptide hydrogel based on phenylboronic acid-o-dihydroxy "click chemistry" cross-linking to promote aggregation and signal transduction of mesenchymal stem cells (MSCs) in the early stage and differentiation toward cartilage, thereby promoting the repair of cartilage damage. Three functional peptide molecules were produced using solid-phase peptide synthesis technology, yielding a purity higher than 95%. DOPA-FEFEFEFEGHSNGLPL (DFP) and PBA-FKFKFKFKGHAVDI (BFP) were coassembled at near-neutral pH to form hydrogels (C Gels) based on phenylboronic acid-o-dihydroxy click chemistry cross-linking and effectively loaded transforming growth factor (TGF)-ß1 with a release period of up to 2 weeks. Furthermore, chondrocytes and bone marrow mesenchymal stem cells (BMSCs) were cocultured with functional peptide hydrogels, and the results displayed that the coassembled functional peptide hydrogel group C Gels significantly promoted the proliferation of chondrocytes and MSCs. The chondrocyte markers collagen type I, collagen type II, and glycosaminoglycan (GAG) in the coassembled functional peptide hydrogel group were significantly higher than those in the control group, indicating that it can induce the differentiation of MSCs into cartilage. In vivo experiments demonstrated that the size and thickness of the new cartilage in the compound gel group were the most beneficial to cartilage regeneration. These results indicated that peptide hydrogels are a promising therapeutic option for cartilage regeneration.


Asunto(s)
Ácidos Borónicos , Cartílago Articular , Hidrogeles , Hidrogeles/química , Cartílago Articular/metabolismo , Condrocitos , Diferenciación Celular , Péptidos/farmacología , Péptidos/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Factor de Crecimiento Transformador beta1/metabolismo , Condrogénesis , Ingeniería de Tejidos/métodos
8.
Microbiome ; 12(1): 37, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388458

RESUMEN

BACKGROUND: Host-microbial interactions are expected to affect species' adaptability to climate change but have rarely been explored in ectothermic animals. Some studies have shown that short-term warming reduced gut microbial diversity that could hamper host functional performance. RESULTS: However, our longitudinal experiments in semi-natural conditions demonstrated that warming decreased gut microbiota diversity at 2 months, but increased diversity at 13 and 27 months in a desert lizard (Eremias multiocellata). Simultaneously, long-term warming significantly increased the antibacterial activity of serum, immune responses (higher expression of intestinal immune-related genes), and the concentration of short-chain fatty acids (thereby intestinal barrier and immunity) in the lizard. Fecal microbiota transplant experiments further revealed that increased diversity of gut microbiota significantly enhanced antibacterial activity and the immune response of lizards. More specifically, the enhanced immunity is likely due to the higher relative abundance of Bacteroides in warming lizards, given that the bacteria of Bacteroides fragilis regulated IFN-ß expression to increase the immune response of lizards under a warming climate. CONCLUSIONS: Our study suggests that gut microbiota can help ectotherms cope with climate warming by enhancing host immune response, and highlights the importance of long-term studies on host-microbial interactions and their biological impacts.


Asunto(s)
Microbioma Gastrointestinal , Lagartos , Animales , Lagartos/microbiología , Cambio Climático , Bacterias/genética , Antibacterianos
9.
Zool Res ; 44(6): 1064-1079, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37914522

RESUMEN

The timing of mammalian diversification in relation to the Cretaceous-Paleogene (KPg) mass extinction continues to be a subject of substantial debate. Previous studies have either focused on limited taxonomic samples with available whole-genome data or relied on short sequence alignments coupled with extensive species samples. In the present study, we improved an existing dataset from the landmark study of Meredith et al. (2011) by filling in missing fragments and further generated another dataset containing 120 taxa and 98 exonic markers. Using these two datasets, we then constructed phylogenies for extant mammalian families, providing improved resolution of many conflicting relationships. Moreover, the timetrees generated, which were calibrated using appropriate molecular clock models and multiple fossil records, indicated that the interordinal diversification of placental mammals initiated before the Late Cretaceous period. Additionally, intraordinal diversification of both extant placental and marsupial lineages accelerated after the KPg boundary, supporting the hypothesis that the availability of numerous vacant ecological niches subsequent to the mass extinction event facilitated rapid diversification. Thus, our results support a scenario of placental radiation characterized by both basal cladogenesis and active interordinal divergences spanning from the Late Cretaceous into the Paleogene.


Asunto(s)
Marsupiales , Placenta , Humanos , Femenino , Embarazo , Animales , Filogenia , Marsupiales/genética , Alineación de Secuencia/veterinaria , Mamíferos/genética , Evolución Biológica
10.
RSC Adv ; 13(48): 33743-33753, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38020034

RESUMEN

To counter the hyperspectral detection under the background of vegetation, a light scattering camouflage polyvinyl alcohol membrane containing lithium chloride, chlorophyll (Chl) and titanium dioxide (TD) particles was developed according to the bionic principle. Based on the reflectance and transmittance of the membrane, the optical constants of all components of the membrane were inverted via the ray tracing model and four flux Kubelka-Munk model. Using the determined optical constants, the reflectances of the membranes with different component contents were predicted through the model, and the effects of TD, Chl and water contents on the reflectance of the membrane were elucidated, respectively. Besides, a military specification of the USA in the region of 760 to 1200 nm and an Osmanthus fragrans leaf were used as a spectrum requirement and a simulation object of the camouflage membrane, respectively, to determine the appropriate contents of TD, Chl and water. It is found that when the volume fractions of TD, Chl and water are 0.7%, 5% and 50%, respectively, the 0.3 mm thick membrane can not only meet the military specification but also exhibit a reflection spectrum similar to that of the leaf with a similarity of 0.976.

11.
ESC Heart Fail ; 10(6): 3622-3636, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37798907

RESUMEN

AIMS: Left ventricular remodelling subsequent to myocardial infarction (MI) constitutes a pivotal underlying cause of heart failure. Intervention with the nontoxic endogenous aryl hydrocarbon receptor (AHR) agonist 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) in the acute phase of MI has been shown to ameliorate cardiac function, but its role in the chronic phase remains obscured. This study explores the beneficial role of ITE in delaying the progression of heart failure in the chronic phase of MI. METHODS AND RESULTS: MI rats established by ligating the left anterior descending coronary artery were treated with the indicated concentration of the AHR agonist ITE or vehicle alone. Echocardiography was performed to determine cardiac structure and function; myocardial morphology and fibrosis were observed by haematoxylin and eosin and Masson's trichrome staining; serum biochemical indices, BNP, and inflammatory cytokine levels were detected by enzyme-linked immunosorbent assay; F4/80+ iNOS+ M1 macrophages and F4/80+ CD206+ M2 macrophages were detected by immunofluorescence; the terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay was used to detect the apoptosis of cardiomyocytes; ultrastructural changes in myocardial tissue were observed by transmission electron microscopy; and Cyp1a1, Akt, P-Akt, p70S6K, P-p70S6K, Bcl-2, Bax, caspase-3, and cleaved caspase-3 protein levels were determined via Western blotting. We found that therapy with the AHR agonist ITE rescued cardiac remodelling and dysfunction in rats with MI and attenuated myocardial fibrosis, inflammation, and mitochondrial damage. Further studies confirmed that ITE dose-dependently improved myocardial cell apoptosis after MI, as demonstrated by reduced levels of the apoptosis-related proteins cleaved caspase-3 and Bax but increased expression levels of Bcl-2. These effects were attributed to ITE-induced activation of AHR receptors, leading to the down-regulation of Akt and p70S6K phosphorylation. CONCLUSIONS: The AHR agonist ITE alleviates cardiomyocyte apoptosis through the Akt/p70S6K signalling pathway, thereby rescuing left ventricular adverse remodelling and cardiac dysfunction after MI.


Asunto(s)
Insuficiencia Cardíaca , Infarto del Miocardio , Ratas , Animales , Caspasa 3 , Proteínas Quinasas S6 Ribosómicas 70-kDa , Proteínas Proto-Oncogénicas c-akt , Receptores de Hidrocarburo de Aril/agonistas , Receptores de Hidrocarburo de Aril/metabolismo , Remodelación Ventricular , Proteína X Asociada a bcl-2 , Infarto del Miocardio/complicaciones , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/metabolismo
12.
Aging Cell ; 22(9): e13917, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37395176

RESUMEN

The naked mole rat (Heterocephalus glaber), bats (e.g., genus Myotis), and elephants (family Elephantidae) are known as long-lived mammals and are assumed to be excellent cancer antagonists. However, whether there are common genetic changes underpinning cancer resistance in these long-lived species is yet to be fully established. Here, we newly generated a high-quality chromosome-level Asian elephant (Elephas maximus) genome and identified that the expanded gene families in elephants are involved in Ras-associated and base excision repair pathways. Moreover, we performed comparative genomic analyses of 12 mammals and examined genes with signatures of positive selection in elephants, naked mole rat, and greater horseshoe bat. Residues at positively selected sites of CDR2L and ALDH6A1 in these long-lived mammals enhanced the inhibition of tumor cell migration compared to those in short-lived relatives. Overall, our study provides a new genome resource and a preliminary survey of common genetic changes in long-lived mammals.


Asunto(s)
Elefantes , Neoplasias , Animales , Elefantes/genética , Mamíferos/genética , Neoplasias/genética , Genómica , Cromosomas , Ratas Topo/genética
13.
EMBO J ; 42(17): e112740, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37427458

RESUMEN

Lifespan varies significantly among mammals, with more than 100-fold difference between the shortest and longest living species. This natural difference may uncover the evolutionary forces and molecular features that define longevity. To understand the relationship between gene expression variation and longevity, we conducted a comparative transcriptomics analysis of liver, kidney, and brain tissues of 103 mammalian species. We found that few genes exhibit common expression patterns with longevity in the three organs analyzed. However, pathways related to translation fidelity, such as nonsense-mediated decay and eukaryotic translation elongation, correlated with longevity across mammals. Analyses of selection pressure found that selection intensity related to the direction of longevity-correlated genes is inconsistent across organs. Furthermore, expression of methionine restriction-related genes correlated with longevity and was under strong selection in long-lived mammals, suggesting that a common strategy is utilized by natural selection and artificial intervention to control lifespan. Our results indicate that lifespan regulation via gene expression is driven through polygenic and indirect natural selection.


Asunto(s)
Longevidad , Mamíferos , Animales , Mamíferos/clasificación , Mamíferos/genética , Mamíferos/crecimiento & desarrollo , Mamíferos/metabolismo , Longevidad/genética , Perfilación de la Expresión Génica , Expresión Génica , Hígado/metabolismo , Encéfalo/metabolismo , Riñón/metabolismo , Humanos , Masculino , Femenino
14.
Langmuir ; 39(30): 10565-10575, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37474454

RESUMEN

The difficulty of short-process bonded Nd-Fe-B magnet waste recycling lies in the effective removal of the cured polymer matrix while protecting the magnetic powder. In this study, the polymer matrix in bonded Nd-Fe-B magnet waste was destroyed using sodium hydroxide ethanol solution, and the effect of the recycling process on the magnetic powders was studied. The nonmagnetic polymer matrix was removed, while the magnetic phase was not destroyed. The carbon and oxygen contents of the recycled magnetic powders decreased by 92.96 and 89.30%, respectively, while the MS (saturation magnetization), Mr (remanence), and Hcj (coercivity) values of the recycled magnetic powders were 99.8, 98.5, and 95.9% of the original magnetic powders, respectively. The curing and decomposition processes of the polymer matrix were also analyzed. During the curing process, dicyandiamide and bisphenol A epoxy resin acted as bridges and skeletons, respectively, finally forming a thermosetting three-dimensional network structure. In the alkaline alcohol solution, the bridges and skeletons were destroyed by the free hydroxyl groups and free hydrogen radicals in ethanol, and small molecular products were dissolved in the solution.

15.
Front Pediatr ; 11: 1205155, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37342532

RESUMEN

Small-intestinal duplication is a rare congenital developmental anomaly that is mainly single; multiple small-intestinal duplications are rare. Most malformations are located in the ileocecal region. The primary surgical treatment is complete resection of the malformations and adjacent intestinal ducts. However, the ileocecal junction plays an important role in children, and it is difficult to preserve it; multiple intestinal repairs increase the risk of postoperative intestinal fistula, which is a challenge for pediatric surgeons. Herein, we report a case of ileocecal preservation surgery for the treatment of multiple small intestinal duplication malformations near the ileocecal area. The child underwent laparoscopically assisted cyst excision and multiple intestinal repairs and had good postoperative recovery and follow-up.

16.
Sheng Wu Gong Cheng Xue Bao ; 39(4): 1462-1476, 2023 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-37154317

RESUMEN

Antibiotics are playing an increasingly important role in clinical antibacterial applications. However, their abuse has also brought toxic and side effects, drug-resistant pathogens, decreased immunity and other problems. New antibacterial schemes in clinic are urgently needed. In recent years, nano-metals and their oxides have attracted wide attention due to their broad-spectrum antibacterial activity. Nano-silver, nano-copper, nano-zinc and their oxides are gradually applied in biomedical field. In this study, the classification and basic properties of nano-metallic materials such as conductivity, superplasticity, catalysis, and antibacterial activities were firstly introduced. Secondly, the common preparation techniques, including physical, chemical and biological methods, were summarized. Subsequently, four main antibacterial mechanisms, such as cell membrane, oxidative stress, DNA destruction and cell respiration reduction, were summarized. Finally, the effect of size, shape, concentration and surface chemical characteristics of nano-metals and their oxides on antibacterial effectiveness and the research status of biological safety such as cytotoxicity, genotoxicity and reproductive toxicity were reviewed. At present, although nano-metals and their oxides have been applied in medical antibacterial, cancer treatment and other clinical fields, some issues such as the development of green preparation technology, the understanding of antibacterial mechanism, the improvement of biosafety, and the expansion of application fields, require further exploration.


Asunto(s)
Nanopartículas del Metal , Óxidos , Óxidos/farmacología , Óxidos/química , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Zinc , Cobre
17.
Adv Sci (Weinh) ; 10(16): e2301312, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37069783

RESUMEN

The development of low-cost RE-Fe-B sintered magnets with large La/Ce content is of great significance for the balanced utilization of rare earth (RE) resources, but it is limited by reduced magnetic properties. In this work, the coercivity (Hcj ), remanence (Br ), maximum energy product [(BH)max ], and temperature stability are simultaneously enhanced for magnets with LaCe accounting for 40 wt% of the total RE. The synergistic regulation of the REFe2 phase, Ce-valence, and grain boundaries (GBs) in RE-Fe-B sintered magnets is realized for the first time by introducing appropriate La elements. The La elements inhibit the generation of the REFe2 phase and tend to stay in the triple junctions, promoting the segregation of the RE/Cu/Ga elements and contributing to the formation of Ce/Nd/Cu/Ga-rich continuous thicker lamellar GBs, and as a result, weakening the detrimental effect on HA caused by La element substitution and enhancing Hcj . In addition, partial La atoms entering the RE2 Fe14 B phase are beneficial for improving the Br and temperature stability of the magnets and promoting the Ce3+ ion ratio, which also provides additional benefit for Br . The findings provide an effective and feasible way to co-enhance the remanence and coercivity of RE-Fe-B sintered magnets with high Ce content.

18.
Anal Chem ; 95(12): 5331-5339, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36926822

RESUMEN

As an enzyme-free exponential nucleic acid amplification method, the click chemistry-mediated ligation chain reaction (ccLCR) has shown great prospects in the molecular diagnosis. However, the current optics-based ccLCR is challenged by remarkable nonspecific amplification, severely hindering its future application. This study demonstrated that the severe nonspecific amplification was generated probably due to high random collision in the high DNA probe concentration (µM level). To solve this hurdle, a nucleic acid template-dominated ccLCR was constructed using nM-level DNA probes and read on an electrochemical platform (cc-eLCR). Under the optimal conditions, the proposed cc-eLCR detected a low-level nucleic acid target (1 fM) with a single-base resolution. Furthermore, this assay was applied to detect the target of interest in cell extracts with a satisfactory result. The proposed cc-eLCR offers huge possibility for click chemistry-mediated enzyme-free exponential nucleic acid amplification in the application of medical diagnosis and biomedical research.


Asunto(s)
Técnicas Biosensibles , ARN , Química Clic/métodos , Técnicas Biosensibles/métodos , ADN/química , Sondas de ADN/genética , Sondas de ADN/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Electroquímicas/métodos , Límite de Detección , Hibridación de Ácido Nucleico
19.
Materials (Basel) ; 16(6)2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36984134

RESUMEN

Orbital angular momentum (OAM) has made it possible to regulate classical waves in novel ways, which is more energy- or information-efficient than conventional plane wave technology. This work aims to realize the transition of antenna radiation mode through the rapid design of an anisotropic dielectric lens. The deep learning neural network (DNN) is used to train the electromagnetic properties of dielectric cell structures. Nine variable parameters for changing the dielectric unit structure are present in the input layer of the DNN network. The trained network can predict the transmission phase of the unit cell structure with greater than 98% accuracy within a specific range. Then, to build the corresponding relationship between the phase and the parameters, the gray wolf optimization algorithm is applied. In less than 0.3 s, the trained network can predict the transmission coefficients of the 31 × 31 unit structure in the arrays with great accuracy. Finally, we provide two examples of neural network-based rapid anisotropic dielectric lens design. Dielectric lenses produce the OAM modes +1, -1, and -1, +2 under TE and TM wave irradiation, respectively. This approach resolves the difficult phase matching and time-consuming design issues associated with producing a dielectric lens.

20.
J Funct Biomater ; 14(2)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36826912

RESUMEN

Porous titanium interbody scaffolds are growing in popularity due to their appealing advantages for bone ingrowth. This study aimed to investigate the biomechanical effects of scaffold materials in both normal and osteoporotic lumbar spines using a finite element (FE) model. Four scaffold materials were compared: Ti6Al4V (Ti), PEEK, porous titanium of 65% porosity (P65), and porous titanium of 80% porosity (P80). In addition, the range of motion (ROM), endplate stress, scaffold stress, and pedicle screw stress were calculated and compared. The results showed that the ROM decreased by more than 96% after surgery, and the solid Ti scaffold provided the lowest ROM (1.2-3.4% of the intact case) at the surgical segment among all models. Compared to solid Ti, PEEK decreased the scaffold stress by 53-66 and the endplate stress by 0-33%, while porous Ti decreased the scaffold stress by 20-32% and the endplate stress by 0-32%. Further, compared with P65, P80 slightly increased the ROM (<0.03°) and pedicle screw stress (<4%) and decreased the endplate stress by 0-13% and scaffold stress by approximately 18%. Moreover, the osteoporotic lumbar spine provided higher ROMs, endplate stresses, scaffold stresses, and pedicle screw stresses in all motion modes. The porous Ti scaffolds may offer an alternative for lateral lumbar interbody fusion.

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