Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 105
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Chemphyschem ; 25(6): e202300835, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38372432

RESUMEN

With the popularity and development of electronic devices, the demand for lithium batteries is increasing, which also puts high demands on the energy density, cycle life and safety of lithium batteries. Gel electrolytes achieve both of these requirements by curing the electrolytes to reduce the interfacial side reactions of lithium metal batteries. The ionic conductivity of the gel electrolytes prepared by in situ curing reach 8.0×10-4  S cm-1 , and the ionic mobility number is 0.53. Meanwhile, the gel electrolytes maintain a stable electrochemical window of 1.0-5.0 V. Benefited with the interfacial regulation of PEGDA gel electrolytes, the gel lithium metal batteries show better cycling stability, and achieved 97 % capacity retention after 200 cycles (0.2 C) with a lower increasing rate of impedance.

2.
Arch Insect Biochem Physiol ; 117(1): e22148, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39250333

RESUMEN

Our previous research reported the influence of 50 µM selenium (Se) on the cytosolization (endocytosis) pathway, which in turn stimulates the growth and development of Bombyx mori. Lately, dynamin is recognized as one of the key proteins in endocytosis. To explore the underlying mechanisms of Se impact, the dynamin gene was knocked down by injecting siRNAs (Dynamin-1, Dynamin-2, and Dynamin-3). This was followed by an analysis of the target gene and levels of silk protein genes, as well as growth and developmental indices, Se-enrichment capacity, degree of oxidative damage, and antioxidant capacity of B. mori. Our findings showed a considerable decrease in the relative expression of the dynamin gene in all tissues 24 h after the interference and a dramatic decrease in the silkworm body after 48 h. RNAi dynamin gene decreased the silkworm body weight, cocoon shell weight, and the ratio of cocoon. In the meantime, malondialdehyde level increased and glutathione level and superoxide dismutase/catalase activities decreased. 50 µM Se markedly ameliorated these growth and physiological deficits as well as decreases in dynamin gene expression. On the other hand, there were no significant effects on fertility (including produced eggs and laid eggs) between the interference and Se treatments. Additionally, the Se content in the B. mori increased after the dynamin gene interference. The dynamin gene was highly expressed in the silk gland and declined significantly after interference. Among the three siRNAs (Dynamin-1, Dynamin-2, and Dynamin-3), the dynamin-2 displayed the highest interference effects to target gene expression. Our results demonstrated that 50 µM Se was effective to prevent any adverse effects caused by dynamin knockdown in silkworms. This provides practical implications for B. mori breeding industry.


Asunto(s)
Bombyx , Dinaminas , Técnicas de Silenciamiento del Gen , Selenio , Animales , Bombyx/genética , Bombyx/crecimiento & desarrollo , Bombyx/metabolismo , Bombyx/efectos de los fármacos , Selenio/farmacología , Dinaminas/genética , Dinaminas/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Larva/crecimiento & desarrollo , Larva/genética , Larva/metabolismo , Larva/efectos de los fármacos , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Femenino , Seda
3.
Phytother Res ; 38(8): 3954-3972, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38837315

RESUMEN

Driven by iron-dependent lipid peroxidation, ferroptosis is regulated by p53 and solute carrier family 7 member 11 (SLC7A11)/glutathione/glutathione peroxidase 4 (GPX4) axis in colorectal cancer (CRC). This study aimed to investigate the influence of curcumin (CUR) on ferroptosis in CRC. The efficacies of CUR on the malignant phenotype of CRC cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, wound healing, and clonogenic assays. The effects of CUR on ferroptosis of CRC cells were evaluated by transmission electron microscopy, lactate dehydrogenase release assay, Fe2+ staining, and analyses of reactive oxygen species, lipid peroxide, malondialdehyde, and glutathione levels. CUR's targets in ferroptosis were predicted by network pharmacological study and molecular docking. With SW620 xenograft tumors, the efficacy of CUR on CRC was investigated, and the effects of CUR on ferroptosis were assessed by detection of Fe2+, malondialdehyde, and glutathione levels. The effects of CUR on expressions of p53, SLC7A11, and GPX4 in CRC cells and tumors were analyzed by quantitative reverse transcription-polymerase chain reaction, western blotting, and immunohistochemistry. CUR suppressed the proliferation, migration, and clonogenesis of CRC cells and xenograft tumor growth by causing ferroptosis, with enhanced lactate dehydrogenase release and Fe2+, reactive oxygen species, lipid peroxide, and malondialdehyde levels, but attenuated glutathione level in CRC. In silico study indicated that CUR may bind p53, SLC7A11, and GPX4, consolidated by that CUR heightened p53 but attenuated SLC7A11 and GPX4 mRNA and protein levels in CRC. CUR may exert an inhibitory effect on CRC by inducing ferroptosis via regulation of p53 and SLC7A11/glutathione/GPX4 axis.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Neoplasias Colorrectales , Curcumina , Ferroptosis , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Proteína p53 Supresora de Tumor , Ferroptosis/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Humanos , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Sistema de Transporte de Aminoácidos y+/metabolismo , Curcumina/farmacología , Animales , Ratones , Línea Celular Tumoral , Transducción de Señal/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Glutatión/metabolismo , Ratones Desnudos , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto , Peroxidación de Lípido/efectos de los fármacos , Glutatión Peroxidasa/metabolismo , Masculino , Simulación del Acoplamiento Molecular , Proliferación Celular/efectos de los fármacos
4.
J Insect Sci ; 23(3)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37256698

RESUMEN

The tachinid fly, Exorista sorbillans, is a notorious ovolarviparous endoparasitoid of the silkworm, Bombyx mori, causing severe damage to silkworm cocoon industry. Silkworm larvae show typically precocious wandering behavior after being parasitized by E. sorbillans; however, the underlying molecular mechanism remains unexplored. Herein, we investigated the changes in the levels of 20-hydroxyecdysone (20E) and juvenile hormone (JH) titer, and they both increased in the hemolymph of parasitized silkworms. Furthermore, we verified the expression patterns of related genes, which showed an upregulation of 20E signaling and biosynthesis genes but a significant downregulation of ecdysone oxidase (EO), a 20E inactivation enzyme, in parasitized silkworms. In addition, related genes of the JH signaling were activated in parasitized silkworms, while related genes of the JH degradation pathway were suppressed, resulting in an increase in JH titer. Notably, the precocious wandering behavior of parasitized silkworms was partly recoverable by silencing the transcriptions of BmCYP302A1 or BmCYP307A1 genes. Our findings suggest that the developmental duration of silkworm post parasitism could be shortened by regulation of 20E and JH titers, which may help silkworm to resist the E. sorbillans infestation. These findings provide a basis for deeper insight into the interplay between silkworms and E. sorbillans and may serve as a reference for the development of a novel approach to control silkworm myiasis.


Asunto(s)
Bombyx , Dípteros , Lepidópteros , Manduca , Animales , Dípteros/metabolismo , Larva , Ecdisona/metabolismo , Lepidópteros/metabolismo , Hormonas Juveniles/metabolismo
5.
Mol Cancer ; 21(1): 144, 2022 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-35836256

RESUMEN

BACKGROUND: The Wnt signaling pathway is a complex network of protein interactions that functions most commonly in embryonic development and cancer, but is also involved in normal physiological processes in adults. The canonical Wnt signaling pathway regulates cell pluripotency and determines the differentiation fate of cells during development. The canonical Wnt signaling pathway (also known as the Wnt/ß-catenin signaling pathway) is a recognized driver of colon cancer and one of the most representative signaling pathways. As a functional effector molecule of Wnt signaling, the modification and degradation of ß-catenin are key events in the Wnt signaling pathway and the development and progression of colon cancer. Therefore, the Wnt signaling pathway plays an important role in the pathogenesis of diseases, especially the pathogenesis of colorectal cancer (CRC). OBJECTIVE: Inhibit the Wnt signaling pathway to explore the therapeutic targets of colorectal cancer. METHODS: Based on studying the Wnt pathway, master the biochemical processes related to the Wnt pathway, and analyze the relevant targets when drugs or inhibitors act on the Wnt pathway, to clarify the medication ideas of drugs or inhibitors for the treatment of diseases, especially colorectal cancer. RESULTS: Wnt signaling pathways include: Wnt/ß-catenin or canonical Wnt signaling pathway, planar cell polarity (Wnt-PCP) pathway and Wnt-Ca2+ signaling pathway. The Wnt signaling pathway is closely related to cancer cell proliferation, stemness, apoptosis, autophagy, metabolism, inflammation and immunization, microenvironment, resistance, ion channel, heterogeneity, EMT/migration/invasion/metastasis. Drugs/phytochemicals and molecular preparations for the Wnt pathway of CRC treatment have now been developed. Wnt inhibitors are also commonly used clinically for the treatment of CRC. CONCLUSION: The development of drugs/phytochemicals and molecular inhibitors targeting the Wnt pathway can effectively treat colorectal cancer clinically.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Transición Epitelial-Mesenquimal , Humanos , Microambiente Tumoral , Vía de Señalización Wnt , beta Catenina/metabolismo
6.
Proc Biol Sci ; 289(1982): 20221011, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36100029

RESUMEN

The pet trade and Traditional Chinese Medicine (TCM) consumption are major drivers of global biodiversity loss. Tokay geckos (Gekko gecko) are among the most traded reptile species worldwide. In Hong Kong, pet and TCM markets sell tokay geckos while wild populations also persist. To clarify connections between trade sources and destinations, we compared genetics and stable isotopes of wild tokays in local and non-local populations to dried individuals from TCM markets across Hong Kong. We found that TCM tokays are likely not of local origin. Most wild tokays were related to individuals in South China, indicating a probable natural origin. However, two populations contained individuals more similar to distant populations, indicating pet trade origins. Our results highlight the complexity of wildlife trade impacts within trade hubs. Such trade dynamics complicate local legal regulation when endangered species are protected, but the same species might also be non-native and possibly damaging to the environment.


Asunto(s)
Especies en Peligro de Extinción , Lagartos , Animales , Animales Salvajes , Biodiversidad , Humanos , Medicina Tradicional
7.
BMC Neurol ; 22(1): 119, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35337288

RESUMEN

BACKGROUND: Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation to modulate cortical activity for improving motor function. However, the different tDCS applications for modulating cortical activity and dual task gait performance in chronic stroke have not yet been investigated. This study investigated the effects of different tDCS applications on dual task gait performance and contralesional M1 activation in chronic stroke. METHODS: Forty-eight participants were randomized to anodal, bilateral, cathodal, and sham tDCS groups. Each group received 20 min of tDCS stimulation, except the sham group. Gait performance was measured by GaitRite system during cognitive dual task (CDT) walking, motor dual task (MDT) walking, and single walking (SW). Contralesional M1 activity of unaffected tibialis anterior (TA) was measured using transcranial magnetic stimulation (TMS). Intragroup difference was analyzed by Wilconxon sign ranks test with Bonferroni correction, and Kruskal-Wallis one-way analysis of variance by ranks was used for intergroup comparisons, followed by post-hoc Mann-Whitney U tests with Bonferroni correction. RESULTS: The bilateral tDCS (p = 0.017) and cathodal tDCS (p = 0.010) improved the CDT walking speed more than sham group. The bilateral tDCS (p = 0.048) and cathodal tDCS (p = 0.048) also improved the MDT walking speed more than sham group. Furthermore, bilateral tDCS (p = 0.012) and cathodal tDCS (p = 0.040) increased the silent period (SP) more than the anodal and sham group. Thus, one-session of bilateral and cathodal tDCS improved dual task walking performance paralleled with increasing contralesional corticomotor inhibition in chronic stroke. CONCLUSIONS: Our results indicate that one-session of bilateral and cathodal tDCS increased contralesional corticomotor inhibition and improved dual task gait performance in chronic stroke. TRIAL REGISTRATION: Thai Clinical Trials Registry (TCTR20180116001). Registered prospectively on 16th Jan, 2018 at http://www.thaiclinicaltrials.org .


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Estimulación Transcraneal de Corriente Directa , Humanos , Accidente Cerebrovascular/terapia , Estimulación Transcraneal de Corriente Directa/métodos , Estimulación Magnética Transcraneal , Caminata
8.
Arch Insect Biochem Physiol ; 110(1): e21873, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35112397

RESUMEN

Phosphoacetyl glucosamine mutase (PGM) is the key gene for glycolysis of important metabolic pathways in silkworm, and H2 S (7.5 µM) can promote the growth and development of silkworm. Herein, we used body cavity injection of small-interfering RNA (siRNA) to interfere with the PGM gene in H2 S-treated silkworms. After RNA interference (RNAi), we investigated the growth and development of the silkworm. H2 S treatment could significantly recover the inhibition of body weight, cocoon weight, cocoon shell weight, and cocoon shell ratio by knocking down PGM gene in silkworm, without significant effects on eggs laying and production, and then analyzed the mRNA expression of PGM gene. The interference of siRNA significantly decreased the expression of targeted PGM gene and was concentrated in 48 h followed by gradual recovery. Three interference fragments also showed different interference effects, and siRNA of PGM-3 exerted the highest interference effect to the target gene expression. Fat body had the highest mRNA expression of PGM gene, and the best interference effect was observed after siRNA injection. The results showed that the gene based on H2 S treatment may have an important impact on the growth and development of silkworm by affecting its metabolic pathway.


Asunto(s)
Bombyx , Sulfuro de Hidrógeno , Animales , Bombyx/metabolismo , Técnicas de Silenciamiento del Gen , Glucosamina/metabolismo , Glucosamina/farmacología , Crecimiento y Desarrollo , Sulfuro de Hidrógeno/metabolismo , Sulfuro de Hidrógeno/farmacología , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo
9.
Ecotoxicol Environ Saf ; 236: 113469, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35367881

RESUMEN

Long-term manganese exposure causes a neurodegenerative disorder referred to as manganese poisoning, but the mechanism remains unclear and no specific treatment is available. Oxidative stress is widely recognised as one of the main causes of manganese-induced neurotoxicity. In recent years, the role of histone acetylation in neurodegenerative diseases has been widely concerned. curcumin is a natural polyphenol compound extracted from the rhizome of turmeric and exhibits both antioxidant and neuroprotective properties. Therefore, we aimed to investigate whether and how curcumin protects against manganese-induced neurotoxicity from the perspective of histone acetylation, based on the reversibility of histone acetylation modification. In this study, rats were treated with or without curcumin and subjected to long-term manganese exposure. Results that treatment of manganese decreased the protein expression of H3K18 acetylation and H3K27 acetylation at the promoters of oxidative stress-related genes and inhibited the expression of these genes. Nevertheless, curcumin increased the H3K27 acetylation level at the manganese superoxide dismutase (SOD2) gene promoter and promoted the expression of SOD2 gene. Oxidative damage in the rat striatum as well as learning and memory dysfunction were ameliorated after curcumin treatment. Taken together, our results suggest that the regulation of oxidative stress by histone acetylation may be a key mechanism of manganese-induced neurotoxicity. In addition, curcumin ameliorates Mn-induced neurotoxicity may be due to alleviation of oxidative damage mediated by increased activation of H3K27 acetylation at the SOD2 gene promoter.


Asunto(s)
Curcumina , Intoxicación por Manganeso , Acetilación , Animales , Curcumina/farmacología , Expresión Génica , Histonas/metabolismo , Manganeso/metabolismo , Manganeso/toxicidad , Estrés Oxidativo , Ratas
10.
Phytother Res ; 36(9): 3555-3570, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35708264

RESUMEN

It is being brought to light that smoothened (SMO)-independent non-canonical Hedgehog signaling is associated with the pathogenesis of various cancers. Ursolic acid (UA), a pentacyclic triterpenoid present in many medicinal herbs, manifests potent effectiveness against multiple malignancies including colorectal cancer (CRC). In our previous study, UA was found to protect against CRC in vitro by suppression of canonical Hedgehog signaling cascade. Here, the influence of UA on SMO-independent non-canonical Hedgehog signaling in CRC was investigated in the present study, which demonstrated that UA hampered the proliferation and migration, induced the apoptosis of HCT-116hSMO- cells with SMO gene knockdown, accompanied by the augmented expression of the suppressor of fused (SUFU), and lessened levels of MYC (c-Myc), glioma-associated oncogene (GLI1) and Sonic Hedgehog (SHH), and lowered phosphorylation of protein kinase B (PKB, AKT), suggesting that UA diminished non-canonical Hedgehog signal transduction in CRC. In HCT-116hSMO- xenograft tumor, UA ameliorated the symptoms, impeded the growth and caused the apoptosis of CRC, with heightened SUFU expression, and abated levels of MYC, GLI1, and SHH, and mitigated phosphorylation of AKT, indicating that UA down-regulated non-canonical Hedgehog signaling cascade in CRC. Taken together, UA may alleviate CRC by suppressing AKT signaling-dependent activation of SMO-independent non-canonical Hedgehog pathway.


Asunto(s)
Neoplasias Colorrectales , Triterpenos , Animales , Proliferación Celular , Neoplasias Colorrectales/tratamiento farmacológico , Proteínas Hedgehog/metabolismo , Humanos , Ácido Oleanólico/análogos & derivados , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Triterpenos/farmacología , Proteína con Dedos de Zinc GLI1/genética , Ácido Ursólico
11.
Opt Express ; 29(19): 29960-29971, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34614729

RESUMEN

To meet the current need for high-precision and environment-insensitive measurement of the radius of curvature (ROC), we proposed a transverse differential confocal radius measurement (TDCRM) method based on the optical system of the confocal ROC measurement. Using a D-shaped aperture and the virtual pinhole technology, two signals, analogous to the pre-focus and post-focus signals in the two-detector-based differential confocal radius measurement (DCRM), can be obtained from two segmentations of a single CCD image. The difference of these two signals can be used to precisely determine the cat's-eye and confocal positions, thereby achieving the high-accuracy ROC measurement as DCRM with a relative repeatability of 3.4 ppm. Furthermore, compared to DCRM, no optical alignment is needed after replacing the objective lens, which significantly reduces the time cost of measurements. We believe this novel and high-precision ROC measurement method will widen its application to optical manufacturing and provide an exciting opportunity for mass production of the ROC measurement instrument.

12.
J Appl Toxicol ; 40(12): 1661-1672, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32608101

RESUMEN

Long-term arsenic exposure is a worldwide public health problem that causes serious harm to human health. The liver is the main target organ of arsenic toxicity; arsenic induces disruption of the DNA damage repair pathway, but its mechanisms remain unclear. In recent years, studies have found that epigenetic mechanisms play an important role in arsenic-induced lesions. In this study, we conducted experiments in vitro using normal human liver cells (L-02) to explore the mechanism by which the histone demethylase JHDM2A regulates H3K9 dimethylation (me2) in response to arsenic-induced DNA damage. Our results indicated that arsenic exposure upregulated the expression of JHDM2A, downregulated global H3K9me2 modification levels, increased the H3K9me2 levels at the promoters of base excision repair (BER) genes (N-methylpurine-DNA glycosylase [MPG], XRCC1 and poly(ADP-ribose)polymerase 1) and inhibited their expression levels, causing DNA damage in cells. In addition, we studied the effects of overexpression and inhibition of JHDM2A and found that JHDM2A can participate in the molecular mechanism of arsenic-induced DNA damage via the BER pathway, which may not be involved in the BER process because H3K9me2 levels at the promoter region of the BER genes were unchanged following JHDM2A interference. These results suggest a potential mechanism by which JHDM2A can regulate the MPG and XRCC1 genes in the process of responding to DNA damage induced by arsenic exposure and can participate in the process of DNA damage repair, which provides a scientific basis for understanding the epigenetic mechanisms and treatments for endemic arsenic poisoning.


Asunto(s)
Intoxicación por Arsénico/etiología , Arsenitos/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Daño del ADN , Reparación del ADN , Histonas/metabolismo , Histona Demetilasas con Dominio de Jumonji/metabolismo , Hígado/efectos de los fármacos , Compuestos de Sodio/toxicidad , Intoxicación por Arsénico/enzimología , Intoxicación por Arsénico/genética , Intoxicación por Arsénico/patología , Línea Celular , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , ADN Glicosilasas/genética , ADN Glicosilasas/metabolismo , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Hígado/enzimología , Hígado/patología , Metilación , Poli(ADP-Ribosa) Polimerasa-1/genética , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Regiones Promotoras Genéticas , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X/genética , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X/metabolismo
13.
J Insect Sci ; 20(2)2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32186739

RESUMEN

Hydrogen sulfide (H2S) is a highly poisonous gas with an unpleasant smell of rotten eggs. Previous studies of H2S have primarily focused on its effects on mammalian nervous and respiratory systems. In this study, silkworm developmental parameters and changes in metabolites in response to H2S exposure were investigated using a hemolymph metabolomic approach, based on liquid chromatography-mass spectrometry (LC-MS). The developmental parameters, body weight, cocoon weight, cocoon shell weight, and cocoon shell ratio, were noticeably increased following H2S exposure, with the greatest effects observed at 7.5-µM H2S. Metabolites upregulated under H2S exposure (7.5 µM) were related to inflammation, and included (6Z, 9Z, 12Z)-octadecatrienoic acid, choline phosphate, and malic acid, while hexadecanoic acid was downregulated. Identified metabolites were involved in biological processes, including pyrimidine, purine, and fatty acid metabolism, which are likely to affect silk gland function. These results demonstrate that H2S is beneficial to silkworm development and alters metabolic pathways related to spinning function and inflammation. The present study provides new information regarding the potential functions of H2S in insects and metabolic pathways related to this phenomenon.


Asunto(s)
Bombyx/crecimiento & desarrollo , Sulfuro de Hidrógeno/metabolismo , Animales , Bombyx/efectos de los fármacos , Bombyx/metabolismo , Cromatografía Liquida , Hemolinfa/metabolismo , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/metabolismo , Espectrometría de Masas , Metabolómica
14.
J Nanosci Nanotechnol ; 19(9): 5656-5660, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30961721

RESUMEN

Polypyrrole encapsulated nickel nanorods (PPy@Ni) have been prepared by electro-polymerization using Ni nanorods as template. PPy@Ni were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectrometer, Fourier transform infrared (FTIR) spectra and vibrating sample magnetometry (VSM). The maximum saturation magnetization of PPy@Ni was up to 44.6 emu g-1. Further, PPy@Ni was used as the additive for the conductivity improvement in polymer matrix. Experimental results showed that the electric conductivity reached 1.8×10-3 S m-1 when 5% PPy@Ni was added in the poly(urethane acrylate) matrix by applying a magnetic field. Further tests showed that when the additive concentration increased from 0.1% to 5%, the correspondence saturation magnetization increased from 15.1 emug-1 to 31.3 emug-1. This work provides new light on controllable fabrication of conducting polymer by adding magnetic alignment conductive additives.

15.
BMC Musculoskelet Disord ; 20(1): 367, 2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31399083

RESUMEN

BACKGROUND: Reconstruction for large bone defect of distal tibia after wide resection of tumor is difficult, and the best option remains controversial. This study presents a novel "double-strut" fibula ankle arthrodesis for this issue. METHODS: Nine patients with malignant or aggressive tumors of distal tibia underwent novel "double-strut" fibula ankle arthrodesis after wide tumor resection were retrospectively reviewed. We assessed the bone union time, complications and oncology outcome clinically and radiographically. The Musculoskeletal Tumor Society (MSTS) score and the Foot and Ankle Outcome Score (FAOS) were used to evaluate the functional outcome. RESULTS: The average followup period was 53 ± 46 months. There was no deep infection or graft fracture observed in this series. Internal fixation loosening was found in one case. In these patients, eight achieved union at both proximal and distal junctions, while one achieved union only distally. The mean union time of the proximal junctions and distal junctions was 10.5 ± 1.6 months and 8.7 ± 2.3 months, respectively. The mean postoperative MSTS score was 83% ± 8%. The subscales of FAOS indicating the most problem was Sport and Recreation Function with a mean score of 18 ± 11. At the final follow-up, one of them (1/9, 11%) experienced local recurrence in soft tissue and received another resection surgery, and four (4/9, 44%) patients developed lung metastases. CONCLUSIONS: For large bone defect of distal tibia, this novel "double-strut" fibula reconstruction can be a viable alternative, which is capable of achieving durable ankle fusion and functional salvaged limb with low rate of complications.


Asunto(s)
Artrodesis/métodos , Neoplasias Óseas/cirugía , Trasplante Óseo/métodos , Peroné/trasplante , Recuperación del Miembro/métodos , Osteosarcoma/cirugía , Adolescente , Adulto , Articulación del Tobillo/cirugía , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteotomía/efectos adversos , Estudios Retrospectivos , Tibia/cirugía , Resultado del Tratamiento , Adulto Joven
16.
Luminescence ; 34(2): 200-204, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30680910

RESUMEN

It is a challenging task to prepare well-dispersed and highly luminescent quantum dots (QDs) powder and a new strategy is reported in this article. Sodium carboxymethyl starch (CMS-Na) was employed in this work to prepare the QDs-starch composite. Ultraviolet (UV) light shows that the blank starches had no fluorescence, while the QDs-starches were highly luminescent. Scanning electron microscopy (SEM) observation shows that the QDs-starch composite has the typical particle morphology with the diameter around 200 nm. Energy dispersive X-ray spectroscopy (EDX) results show that there are intensive tellurium (Te) and cadmium (Cd) element signals. Combined fluorescent lifetime and steady-state spectrometer show that the QDs-starch quantum yields (QYs) increase when the QDs loading increases from 1 × 10-6 mol/g to 2 × 10-6 mol/g, but when the loadings further increase, the QYs decrease slightly. For the red colour (λem  = 660 nm) QDs, the QYs can reach to as high as 28.2%, and for the other colour QDs they can also have the QYs above 22%. Time-resolved photobleaching experiments show that the fluorescent QDs-starch composite has a half-decay time of 40.23 s. These results indicate that the CMS-Na is a promising QDs dispersant to obtain high QY QD composites.


Asunto(s)
Luminiscencia , Puntos Cuánticos/química , Teoría Cuántica , Almidón/análogos & derivados , Almidón/química , Rayos Ultravioleta
17.
J Nanosci Nanotechnol ; 18(10): 6949-6956, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29954515

RESUMEN

Nitrogen doped carbon nanocage with graphitic shell (NGCS) was fabricated through in-situ solid reaction between calcium acetate and dicyandiamide in an inert atmosphere followed by acid etching. The role played by the calcium acetate (Ca(Ac)2) and dicyandiamide (DCD) during the synthesis process is one-stone-two-birds. Calcium acetate plays multiple functions: template agent, graphitization catalyst, and carbon source. Dicyandiamide can be considered as the nitrogen sources and the chemical reaction agent that can be reacted with calcium acetate to form it into CaCN2. The NGCS obtained at 800 °C has a specific surface area of 420 m2/g and nitrogen content of 8.87 at%. The excellent electrochemical performance can be attributed to the combination effects of porous structure, nitrogen doping and graphitized nanocage shell of NGCS electrode. The hollow structure serves as the reservoir for fast electrolyte ion supplement. Nitrogen groups not only improve the wettability of interfaces between carbon surface and electrolyte, but also generate extra pseudocapacitance through redox reaction. The graphitic carbon nanocage shell can enhance the conductivity and facilitates the fast charge transfer. At a current density of 0.5 A/g, the specific capacitance of the NGCS-800 electrode is 215 F/g. Furthermore, the NGCS-800 electrode exhibits excellent rate capability (80% capacitance retention at 10 A/g) and outstanding cycling stability (96.89% capacitance retention after 5000 cycles). These intriguing results demonstrate that nitrogen doped carbon with graphitic shell will be highly promising as electrode materials for supercapacitors and other energy storage and conversation applications.

18.
J Arthroplasty ; 33(5): 1507-1514, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29366726

RESUMEN

BACKGROUND: Hip dislocation is a major complication of total femoral prosthetic reconstruction (TFR) after femoral tumor resection. Hip dislocation can occur because of inadequate functional abductor musculature, inadequate hip capsule repair, or a long lever arm after total femur replacement. To eliminate the negative effects of these factors on the risk of hip dislocation, the use of artificial ligaments may help to increase the stability of the hip joint. We aimed to determine whether application of an artificial ligament would improve limb function and active range of movement (ROM) after TFR. METHODS: Fifty-eight patients who underwent femoral tumor resection and TFR were included. A band-shaped artificial ligament was wrapped spirally around the proximal site of the total femur prosthesis for periacetabular soft tissue reconstruction in 12 patients. The other 46 patients did not consent to receiving the artificial ligament. Complications including hip dislocation and infection, limb function, and active hip ROM were compared between patients who did and did not receive the artificial ligament. RESULTS: The hip dislocation rate was lower in the patients who received the artificial ligament. The risk of deep infection did not differ between groups. The group that received the ligament also achieved better limb function and active ROM on flexion and abduction. CONCLUSION: Patients treated with total femur resection and endoprosthetic replacement with an artificial ligament for periacetabular soft tissue reconstruction had a more stable hip joint, better limb function, and greater active hip ROM than did patients who did not receive an artificial ligament.


Asunto(s)
Artroplastia de Reemplazo , Neoplasias Femorales/cirugía , Fémur/cirugía , Luxación de la Cadera/prevención & control , Articulación de la Cadera/cirugía , Prótesis de Cadera , Adolescente , Adulto , Anciano , Artroplastia de Reemplazo de Cadera , Niño , Femenino , Neoplasias Femorales/complicaciones , Luxación de la Cadera/etiología , Humanos , Ligamentos/cirugía , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
19.
Clin Orthop Relat Res ; 475(12): 3060-3070, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28948491

RESUMEN

BACKGROUND: Pelvic reconstruction after periacetabular tumor resection is technically difficult and characterized by a high complication rate. Although endoprosthetic replacement can result in immediate postoperative functional recovery, biologic reconstructions with autograft may provide an enhanced prognosis in patients with long-term survival; however, little has been published regarding this approach. We therefore wished to evaluate whether whole-bulk femoral head autograft that is not contaminated by tumor can be used to reconstruct segmental bone defects after intraarticular resection of periacetabular tumors. QUESTIONS/PURPOSES: In a pilot study, we evaluated (1) local tumor control, (2) complications, and (3) postoperative function as measured by the Musculoskeletal Tumor Society score. METHODS: Between 2009 and 2015, we treated 13 patients with periacetabular malignant or aggressive benign tumors with en bloc resection, bulk femoral head autograft, and cemented THA (with or without a titanium acetabular reconstruction cup), and all were included for analysis here. During that time, the general indications for this approach were (1) patients anticipated to have a good oncologic prognosis and adequate surgical margins to allow this approach, (2) patients whose pelvic bone defects did not exceed two types (Types I + II or Types II + III as defined by Enneking and Dunham), and (3) patients whose medical insurance would not cover what otherwise might have been a pelvic tumor prosthesis. During this period, another 91 patients were treated with pelvic prosthetic replacement, which was our preferred approach. Median followup in this study was 36 months (range, 24-99 months among surviving patients; one patient died 8 months after surgery); no patients were lost to followup. Bone defects were Types II + III in five patients, and Types I + II in eight. After intraarticular resection, ipsilateral femoral head autograft combined with THA was used to reconstruct the segmental bone defect of the acetabulum. In patients with Types I + II resections, the connection between the sacrum and the acetabulum was reestablished with a fibular autograft or a titanium cage filled with dried bone-allograft particles which was enhanced by using a pedicle screw and rod system. Functional evaluation was done in 11 patients who remained alive and maintained the femoral head autograft at final followup; one other patient received secondary resection involving removal of the femoral head autograft and internal fixation, and was excluded from functional evaluation. Endpoints were assessed by chart review. RESULTS: Two patients experienced local tumor recurrence. Finally, eight patients did not show signs of the disease, one patient died of disease for local and distant tumor relapse, and four patients survived, but still had the disease. Three of these four patients had distant metastases without local recurrence and one had local control after secondary resection but still experienced system relapse. We observed the following complications: hematoma (one patient; treated surgically with hematoma clearance), delayed wound healing (one patient; treated by débridement), deep vein thrombosis (one patient), and hip dislocation (one patient; treated with open reduction). The median 1993 Musculoskeletal Tumor Society score was 83% (25 of 30 points; range, 19-29 points), and all patients were community ambulators; one used a cane, three used a walker, and nine did not use any assistive devices. CONCLUSIONS: In this small series at short-term followup, we found that reconstruction of segmental bone defects after intraarticular resection of periacetabular tumors with femoral head autograft does not appear to impede local tumor control; complications were in the range of what might be expected in a series of large pelvic reconstructions, and postoperative function was generally good. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Asunto(s)
Acetábulo/cirugía , Artroplastia de Reemplazo de Cadera , Neoplasias Óseas/cirugía , Trasplante Óseo/métodos , Cabeza Femoral/cirugía , Osteotomía , Neoplasias Pélvicas/cirugía , Acetábulo/diagnóstico por imagen , Acetábulo/patología , Adolescente , Adulto , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/instrumentación , Artroplastia de Reemplazo de Cadera/mortalidad , Autoinjertos , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/mortalidad , Neoplasias Óseas/patología , Trasplante Óseo/efectos adversos , Trasplante Óseo/mortalidad , Progresión de la Enfermedad , Femenino , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/patología , Prótesis de Cadera , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Osteotomía/efectos adversos , Osteotomía/mortalidad , Neoplasias Pélvicas/diagnóstico por imagen , Neoplasias Pélvicas/mortalidad , Neoplasias Pélvicas/patología , Proyectos Piloto , Diseño de Prótesis , Estudios Retrospectivos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA