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1.
Cell ; 186(2): 398-412.e17, 2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36669474

RESUMEN

Public health studies indicate that artificial light is a high-risk factor for metabolic disorders. However, the neural mechanism underlying metabolic modulation by light remains elusive. Here, we found that light can acutely decrease glucose tolerance (GT) in mice by activation of intrinsically photosensitive retinal ganglion cells (ipRGCs) innervating the hypothalamic supraoptic nucleus (SON). Vasopressin neurons in the SON project to the paraventricular nucleus, then to the GABAergic neurons in the solitary tract nucleus, and eventually to brown adipose tissue (BAT). Light activation of this neural circuit directly blocks adaptive thermogenesis in BAT, thereby decreasing GT. In humans, light also modulates GT at the temperature where BAT is active. Thus, our work unveils a retina-SON-BAT axis that mediates the effect of light on glucose metabolism, which may explain the connection between artificial light and metabolic dysregulation, suggesting a potential prevention and treatment strategy for managing glucose metabolic disorders.


Asunto(s)
Tejido Adiposo Pardo , Hipotálamo , Ratones , Animales , Humanos , Tejido Adiposo Pardo/metabolismo , Hipotálamo/metabolismo , Termogénesis/fisiología , Retina , Células Ganglionares de la Retina , Glucosa/metabolismo
2.
Mol Pharm ; 21(2): 373-392, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38252032

RESUMEN

Intervertebral disc degeneration (IVDD) is commonly associated with many spinal problems, such as low back pain, and significantly impacts a patient's quality of life. However, current treatments for IVDD, which include conservative and surgical methods, are limited in their ability to fully address degeneration. To combat IVDD, delivery-system-based therapy has received extensive attention from researchers. These delivery systems can effectively deliver therapeutic agents for IVDD, overcoming the limitations of these agents, reducing leakage and increasing local concentration to inhibit IVDD or promote intervertebral disc (IVD) regeneration. This review first briefly introduces the structure and function of the IVD, and the related pathophysiology of IVDD. Subsequently, the roles of drug-based and bioactive-substance-based delivery systems in IVDD are highlighted. The former includes natural source drugs, nonsteroidal anti-inflammatory drugs, steroid medications, and other small molecular drugs. The latter includes chemokines, growth factors, interleukin, and platelet-rich plasma. Additionally, gene-based and cell-based delivery systems are briefly involved. Finally, the limitations and future development of the combination of therapeutic agents and delivery systems in the treatment of IVDD are discussed, providing insights for future research.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Humanos , Calidad de Vida , Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/metabolismo , Péptidos y Proteínas de Señalización Intercelular
3.
J Intensive Care Med ; : 8850666241280900, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39262206

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the risk factors associated with postoperative pulmonary complications(PPCs) in critically ill patients transferred to intensive care unit(ICU) after abdominal surgery and develop a predictive model for this disease. METHODS: Data for 3716 patients who were admitted to ICU after abdominal surgery in Peking University People's Hospital between January 2015 and December 2020 were retrospectively collected and analyzed to identify the risk factors and develop a nomogram prediction model. Data for patients admitted to ICU following abdominal surgery at Peking University People's Hospital from March 2021 to December 2022 were prospectively collected as a validation set to validate and assess the model. RESULTS: 10 independent risk factors for PPCs in critically ill patients transferred to ICU after abdominal surgery were identified. A nomogram prediction model was constructed for PPCs in this group patients, the area under ROC curve was 0.771[95%CI: 0.756,0.786] and 0.759[95%CI: 0.726,0.792] in the training set and validation set, respectively. CONCLUSIONS: In this study, independent risk factors for PPCs in critically ill patients transferred to ICU after abdominal surgery were identified. A nomogram prediction model for PPCs in critically ill surgical population was constructed using these factors, demonstrating a good predictive value.

4.
Phys Chem Chem Phys ; 25(45): 31206-31221, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37955184

RESUMEN

The biological characteristics of planar heterojunction nanomaterials and their interactions with biomolecules are crucial for the potential application of these materials in the biomedical field. This study employed molecular dynamics (MD) simulations to investigate the interactions between proteins with distinct secondary structures (a single α-helix representing the minimal oligomeric domain protein, a single ß-sheet representing the WW structural domain of the Yap65 protein, and a mixed α/ß structure representing the BBA protein) and a planar two-dimensional heterojunction (a GRA/h-BN heterojunction consisting of a graphene nanoplate (GRA) and a hexagonal boron nitride nanoplate (h-BN)). The results indicate that all three kinds of protein can be quickly and stably adsorbed on the GRA/h-BN heterojunction due to the strong van der Waals interaction, regardless of their respective types, structures and initial orientations. Moreover, the proteins exhibit a pronounced binding preference for the hBN region of the GRA/h-BN heterojunction. Upon adsorption, the α-helix structure of the minimal oligomeric domain protein experiences partial or complete denaturation. Conversely, while the secondary structure of the single ß-sheet and mixed α/ß structure (BBA protein) undergoes slight changes (focus on the coil and turn regions), the main α-helix and ß-sheet structures remain intact. The initial orientation significantly impacts the degree of protein adsorption and its position on the GRA/h-BN heterojunction. However, regardless of the initial orientation, proteins can ultimately be adsorbed onto the GRA/h-BN heterojunction. Furthermore, the initial orientation has a minor influence on the structural changes of proteins. Significantly, the combination of different secondary structures helps mitigate the denaturation of a single α-helix structure to some extent. Overall, the adsorption of proteins on GRA/h-BN is primarily driven by van der Waals and hydrophobic interactions. Proteins with ß-sheet or mixed structures exhibit stronger biocompatibility on the GRA/h-BN heterojunction. Our research elucidated the biological characteristics of GRA/h-BN heterojunction nanomaterials and their interactions with proteins possessing diverse secondary structures. It offers a theoretical foundation for considering heterojunction nanomaterials as promising candidates for biomedical applications.


Asunto(s)
Grafito , Grafito/química , Adsorción , Simulación de Dinámica Molecular , Compuestos de Boro/química
5.
Lasers Surg Med ; 55(7): 680-689, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37365922

RESUMEN

BACKGROUND: Dynamic in vivo changes in melanin in melasma lesions after exposure to ultraviolet (UV) irradiation have not been described. OBJECTIVES: To determine whether melasma lesions and nearby perilesions demonstrated different adaptive responses to UV irradiation and whether the tanning responses were different among different locations on face. METHODS: We collected sequential images from real-time cellular resolution full-field optical coherence tomography (CRFF-OCT) at melasma lesions and perilesions among 20 Asian patients. Quantitative and layer distribution analyses for melanin were performed using a computer-aided detection (CADe) system that utilizes spatial compounding-based denoising convolutional neural networks. RESULTS: The detected melanin (D) is melanin with a diameter >0.5 µm, among which confetti melanin (C) has a diameter of >3.3 µm and corresponds to a melanosome-rich package. The calculated C/D ratio is proportional to active melanin transportation. Before UV exposure, melasma lesions had more detected melanin (p = 0.0271), confetti melanin (p = 0.0163), and increased C/D ratio (p = 0.0152) in the basal layer compared to those of perilesions. After exposure to UV irradiation, perilesions have both increased confetti melanin (p = 0.0452) and the C/D ratio (p = 0.0369) in basal layer, and this effect was most prominent in right cheek (p = 0.030). There were however no significant differences in the detected, confetti, or granular melanin areas before and after exposure to UV irradiation in melasma lesions in all the skin layers. CONCLUSIONS: Hyperactive melanocytes with a higher baseline C/D ratio were noted in the melasma lesions. They were "fixed" on the plateau and were not responsive to UV irradiation regardless of the location on face. Perilesions retained adaptability with a dynamic response to UV irradiation, in which more confetti melanin was shed, mainly in the basal layer. Therefore, aggravating effect of UV on melasma was mainly due to UV-responsive perilesions rather than lesions.


Asunto(s)
Melaninas , Melanosis , Humanos , Melaninas/análisis , Melanocitos/química , Melanocitos/patología , Piel/patología , Epidermis/patología , Rayos Ultravioleta
6.
Lasers Med Sci ; 38(1): 236, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37843672

RESUMEN

Conventional 5-aminolevulinic acid-photodynamic (ALA-PDT) therapy (10-20%) has been widely applied for moderate-to-severe acne. The aim of this study is to investigate the effects of non-ablative Q-switched 1064-nm Nd:YAG laser-assisted ALA-PDT with low concentration (2%) on the treatment of acne vulgaris. Enrolled patients were randomly assigned to 2 groups. One group received combined therapy of 2% ALA-PDT and non-ablative Q-switched 1064-nm Nd:YAG laser, and the other received only 2% ALA-PDT. Patients in each group had received 3-session treatments with 4-week intervals (week 0, 4, and 8). Sebum secretion, melanin index, erythema index, and transepidermal water loss (TEWL) were assessed at week 2, 8, 12, and 24. VISIA® skin image system score and global esthetic improvement scale (GAIS) were also evaluated. Twenty-four participants were enrolled and evenly randomized to two groups. Significant improvement in sebum secretion was noted in combined therapy group compared to the monotherapy group at week 12 (37.5% versus 16.3%), and the improvement would still be noted until week 24 (18.3% versus 17.4%). Combined group also showed more severe melanin index and erythema index after treatment. For VISIA® skin analysis, patients in combined group had better percentile ranking in porphyrins and red-light images. There were no significant differences in GAIS at the end of the follow-up between each group, whereas higher proportion of satisfaction was noted in combined group at week 2. With the assistance of laser, low concentrations (2%) of 5-ALA can provide effective phototoxic reactions in treating acne vulgaris. The satisfaction of patients is high with acceptable adverse effects.


Asunto(s)
Acné Vulgar , Láseres de Estado Sólido , Fotoquimioterapia , Humanos , Ácido Aminolevulínico/uso terapéutico , Láseres de Estado Sólido/uso terapéutico , Melaninas , Resultado del Tratamiento , Fotoquimioterapia/métodos , Acné Vulgar/tratamiento farmacológico , Eritema/etiología
7.
Phys Chem Chem Phys ; 24(43): 26879-26889, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36317582

RESUMEN

Due to its advantages of superior oxidation resistance, excellent chemical stability and non-toxicity, molybdenum disulfide (MoS2) has shown prospects in seawater desalination applications. In this manuscript, molecular dynamics (MD) simulation has been employed to explore the effect of charge distribution in MoS2 nanosheets on the desalination performance of the lamellar MoS2 membrane. It is found that the model considering the atomic charge better describes the transport behavior of salt solution in the membranes. The water flux passing through the lamellar MoS2 membrane would be influenced little by the atomic charges in the MoS2 nanosheet. The lamellar MoS2 membrane considering the atomic charge distribution shows a screening effect between Na+ and Cl- ions.

8.
Int J Mol Sci ; 23(23)2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36498953

RESUMEN

Psoriasis is a chronic autoimmune disease, and until now, it remains an incurable disease. Therefore, the development of new drugs or agents that ameliorate the disease will have marketing potential. Taiwanofungus camphoratus (TC) is a specific fungus in Taiwan. It is demonstrated to have anticancer, anti-inflammation, and hepatoprotective effects. However, the effects of TC fermented extract on psoriasis are under investigation. In this research, we studied the ability of TC on antioxidative activity and the efficacy of TC on interleukin-17 (IL-17A)-induced intracellular oxidative stress, inflammation-relative, and proliferation-relative protein expression in human keratinocytes. The results of a DPPH radical scavenging assay, reducing power assay, and hydroxyl peroxide inhibition assay indicated that TC has a potent antioxidant ability. Furthermore, TC could reduce IL-17A-induced intracellular ROS generation and restore the NADPH level. In the investigation of pathogenesis, we discovered TC could regulate inflammatory and cell proliferation pathways via p-IKKα/p-p65 and p-mTOR/p-p70S6k signaling pathways in human keratinocytes. In conclusion, TC showed characteristics such as antioxidant, anti-inflammatory, and anti-psoriatic-associated responses. It is expected to be developed as a candidate for oxidative-stress-induced skin disorders or psoriasis treatment.


Asunto(s)
Productos Biológicos , Queratinocitos , Psoriasis , Humanos , Antiinflamatorios/farmacología , Células HaCaT/efectos de los fármacos , Células HaCaT/metabolismo , Interleucina-17/metabolismo , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , FN-kappa B/metabolismo , Psoriasis/patología , Serina-Treonina Quinasas TOR/metabolismo , Productos Biológicos/farmacología
9.
Int J Mol Sci ; 23(13)2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35806013

RESUMEN

Although nude mice are an ideal photoaging research model, skin biopsies result in inflammation and are rarely performed at baseline. Meanwhile, studies on antiphotoaging antioxidants or rejuvenation techniques often neglect the spontaneous reversal capacity. Full-field optical coherence tomography (FFOCT) can acquire cellular details noninvasively. This study aimed to establish a photoaging and sequential function reversal nude mice model assisted by an in vivo cellular resolution FFOCT system. We investigated whether a picosecond alexandrite laser (PAL) with a diffractive lens array (DLA) accelerated the reversal. In the sequential noninvasive assessment using FFOCT, a spectrophotometer, and DermaLab Combo®, the photodamage percentage recovery plot demonstrated the spontaneous recovery capacity of the affected skin by UVB-induced transepidermal water loss and UVA-induced epidermis thickening. A PAL with DLA not only accelerated skin barrier regeneration with epidermal polarity, but also increased dermal neocollagenesis, whereas the nonlasered group still had >60% collagen intensity loss and 40% erythema from photodamage. Our study demonstrated that FFOCT images accurately resemble the living tissue. The photoaging and sequential function reversal model provides a reference to assess the spontaneous recovery capacity of nude mice from photodamage. This model can be utilized to evaluate the sequential noninvasive photodamage and reversal effects after other interventions.


Asunto(s)
Envejecimiento de la Piel , Animales , Ratones , Ratones Desnudos , Rejuvenecimiento , Piel/patología , Tomografía de Coherencia Óptica , Rayos Ultravioleta
10.
Phys Chem Chem Phys ; 22(14): 7224-7233, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-32207513

RESUMEN

Graphene-based membranes have been extensively explored owing to their excellent separation properties. In this paper, multiple factors regarding desalination performance were investigated by molecular dynamics (MD) simulations. These factors include the interlayer spacing distance (H), the gap width (dG), offset (O), and the number of gaps and layers in a multilayer graphene membrane (MGM). It is found that salt rejection is influenced significantly by the interlayer spacing distance owing to the largest free energy between ions and graphene sheets as well as the relatively larger size of the hydration layer around the ions. The optimal desalting parameter (dG = 1 nm, H = 0.8 nm) was selected; MGM systems based on the optimized parameter exhibited excellent salt rejection for NaCl, MgCl2 and CaCl2 solutions. These results can provide some ideas for the future design of graphene-based membranes.

11.
Mol Pharm ; 16(3): 987-994, 2019 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-30624945

RESUMEN

A combination of different chemotherapy approaches can obtain the best response for many cancers. However, the greatest challenge is the development of a nanoparticle formulation that can encapsulate different chemotherapeutic agents to achieve the proper synergetic chemotherapy for the tumor. Here, amphiphilic ferrocenium-tetradecyl (Fe-C14) was constructed to form cationic micelles in an aqueous solution via self-assembly. Then, it was coated by hyaluronic acid (HA) through electrostatic interactions to generate HA-Fe-C14 micelles. The HA-Fe-C14 micelles were used to deliver doxorubicin (DOX), and it showed that the DOX could be released rapidly under a high-GSH tumor environment. The HA-Fe-C14/DOX micelles were able to accumulate efficiently in tumor and showed significant anticancer effect both in vitro and in vivo. These results suggest that HA-Fe-C14/DOX micelles are a useful drug delivery system that enhances synergic antitumor treatment effects.


Asunto(s)
Doxorrubicina/química , Doxorrubicina/uso terapéutico , Sistemas de Liberación de Medicamentos , Compuestos Ferrosos/química , Glutatión/química , Ácido Hialurónico/química , Metalocenos/química , Micelas , Neoplasias/terapia , Alcanos/química , Animales , Supervivencia Celular/efectos de los fármacos , Terapia Combinada , Liberación de Fármacos , Compuestos Ferrosos/síntesis química , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/patología , Células PC-3 , Solubilidad , Resultado del Tratamiento , Carga Tumoral
13.
Phys Chem Chem Phys ; 20(45): 28886-28893, 2018 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-30420980

RESUMEN

Nanopore-based DNA sequencing is considered to be a low-cost, high resolution and superfast method. Solid state nanopores, especially MoS2 nanopores, have been considered to be a promising choice for DNA sequencing. However, researchers still have a very limited understanding of the effects of multiple factors on MoS2-based DNA sequencing. In this study, the effects of the applied voltage and the diameter of the MoS2 nanopore on the resolution of DNA sequencing were investigated. Our results demonstrate that the translocation time of DNA can increase with a decrease in the applied voltage. DNA can be stretched significantly to translocate a 2 nm nanopore under a high applied voltage (>400 mV nm-1). To achieve a 1 base per µs translocation speed (1 GHz bandwidth), we suggest that three methods could be applied, including a decrease in the applied voltage, a decrease in the diameter of the MoS2 nanopore or modification of the MoS2 nanopore. In addition, the size of the nanopore can severely affect the possibility of DNA entering the nanopore, and the translocation time of DNA could be significantly increased with a smaller MoS2 nanopore. These findings may help to design MoS2 nanopores with higher resolution for use in DNA sequencing.


Asunto(s)
ADN/química , Disulfuros/química , Molibdeno/química , Nanoporos , Secuencia de Bases , Técnicas Electroquímicas/métodos , Simulación de Dinámica Molecular , Análisis de Secuencia de ADN/métodos
14.
Langmuir ; 33(42): 11321-11331, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-28666388

RESUMEN

The crystallization mechanism for natural mineral, especially the role of biological molecules in biomineralization, is still under debate. Protein adsorption on material surfaces plays a key role in biomineralization. In this article, molecular dynamics (MD) simulations were performed to systematically investigate the adsorption behavior of struthio camelus eggshell protein struthiocalcin-1 (SCA-1) on the calcite (104) surface with several different starting orientations in an explicit water environment. For each binding configuration, detailed adsorption behaviors and a mechanism were presented with the analysis of interaction energy, binding residues, hydrogen bonding, and structures (such as DSSP, dipole moment, and the electrostatic potential calculation). The results indicate that the positively charged and polar residues are the dominant residues for protein adsorption on the calcite (104) surface, and the strong electrostatic interaction drives the binding of model protein to the surface. The hydrogen bond bridge was found to play an important role in surface interactions as well. These results also demonstrate that SCA-1 is relatively rigid in spite of strong adsorption with few structural changes in α-helix and ß-sheet contents. The results of the orientation calculation suggest that the dipole moment of the protein tends to remain parallel to calcite in most stable cases, which was confirmed by electrostatic potential isosurfaces analysis.


Asunto(s)
Carbonato de Calcio/química , Adsorción , Proteínas del Huevo , Enlace de Hidrógeno , Modelos Moleculares , Simulación de Dinámica Molecular , Propiedades de Superficie
15.
Phys Chem Chem Phys ; 19(44): 30031-30038, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29094132

RESUMEN

Development of high-efficiency and low-cost seawater desalination technologies is critical to solving the global water crisis. Herein we report a fast water filtering method with high salt rejection by boron nitride nanotubes (BNNTs). The effect of the radius of BNNTs on water filtering and salt rejection was investigated by molecular dynamics (MD) simulation. Our simulation results demonstrate that fast water permeation and high salt rejection could be achieved by BNNT(7,7) under both high pressure and low pressure. The potential of mean force (PMF) of Na+ ion and water molecule through BNNT(7,7) further revealed the mechanism of seawater desalination by BNNT(7,7). Using BNNT(7,7) array, a 10 cm2 nanotube membrane with 1.5 × 1013 pores per cm2 will produce freshwater with a flow rate of 98 L per day per MPa under 100 MPa. Our study shows the potential application of BNNTs membrane for fast and efficient desalination.

16.
BMC Med Genet ; 16: 66, 2015 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-26290326

RESUMEN

BACKGROUND: Gout is a common arthritic disease resulting from elevated serum uric acid (SUA) level. A large meta-analysis including 28,141 individuals identified nine single nucleotide polymorphisms (SNPs) associated with altered SUA level in a Caucasian population. However, raised SUA level alone is not sufficient for the development of gout arthritis and most of these SNPs have not been studied in a Han Chinese population. Here, we performed a case-control association analysis to investigate the relationship between these SUA correlated SNPs and gout arthritis in Han Chinese. METHODS: A total of 622 ascertained gout p9atients and 917 healthy controls were genotyped. Genome-wide significant SNPs, rs12129861, rs780094, rs734553, rs742132, rs1183201, rs12356193, rs17300741 and rs505802 in the previous SUA study, were selected for our analysis. RESULTS: No deviation from the Hardy-Weinberg equilibrium was observed either in the case or control cohorts (corrected p > 0.05). Three SNPs, rs780094 (located in GCKR, corrected p = 1.78E(-4), OR = 0.723), rs1183201 (located in SLC17A1, corrected p = 1.39E(-7), OR = 0.572) and rs505802 (located in SLC22A12, corrected p = 0.007, OR = 0.747), were significantly associated with gout on allelic level independent of potential cofounding traits. While the remaining SNPs were not replicated. We also found significant associations of uric acid concentrations with these three SNPs (rs780094 in GCKR, corrected p = 3.94E(-5); rs1183201 in SLC17A1, corrected p = 0.005; rs505802 in SLC22A12, corrected p = 0.003) and of triglycerides with rs780094 (located in GCKR, corrected p = 2.96E(-4)). Unfortunately, SNP-SNP interactions for these three significant SNPs were not detected (rs780094 vs rs1183201, p = 0.402; rs780094 vs rs505802, p = 0.434; rs1183201 vs rs505802, p = 0.143). CONCLUSIONS: Three SUA correlated SNPs in Caucasian population, rs780094 in GCKR, rs1183201 in SLC17A1 and rs505802 in SLC22A12 were confirmed to be associated with gout arthritis and uric acid concentrations in Han Chinese males. Considering genetic differences among populations and complicated pathogenesis of gout arthritis, more validating tests in independent populations and relevant functional experiments are suggested in future.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Pueblo Asiatico/genética , Gota/genética , Transportadores de Anión Orgánico/genética , Proteínas de Transporte de Catión Orgánico/genética , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo I/genética , Estudios de Casos y Controles , Técnicas de Genotipaje , Gota/etnología , Humanos , Modelos Logísticos , Masculino
17.
Mol Ecol ; 24(4): 771-84, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25581109

RESUMEN

Identifying the molecular markers for complex quantitative traits in natural populations promises to provide novel insight into genetic mechanisms of adaptation and to aid in forecasting population dynamics. In this study, we investigated single nucleotide polymorphisms (SNPs) using candidate gene approach from high- and low-fecundity populations of the brown planthopper (BPH) Nilaparvata lugens Stål (Hemiptera: Delphacidae) divergently selected for fecundity. We also tested whether the population fecundity can be predicted by a few SNPs. Seven genes (ACE, fizzy, HMGCR, LpR, Sxl, Vg and VgR) were inspected for SNPs in N. lugens, which is a serious insect pest of rice. By direct sequencing of the complementary DNA and promoter sequences of these candidate genes, 1033 SNPs were discovered within high- and low-fecundity BPH populations. A panel of 121 candidate SNPs were selected and genotyped in 215 individuals from 2 laboratory populations (HFP and LFP) and 3 field populations (GZP, SGP and ZSP). Prior to association tests, population structure and linkage disequilibrium (LD) among the 3 field populations were analysed. The association results showed that 7 SNPs were significantly associated with population fecundity in BPH. These significant SNPs were used for constructing general liner models with stepwise regression. The best predictive model was composed of 2 SNPs (ACE-862 and VgR-816 ) with very good fitting degree. We found that 29% of the phenotypic variation in fecundity could be accounted for by only two markers. Using two laboratory populations and a complete independent field population, the predictive accuracy was 84.35-92.39%. The predictive model provides an efficient molecular method to predict BPH fecundity of field populations and provides novel insights for insect population management.


Asunto(s)
Fertilidad/genética , Genética de Población , Hemípteros/genética , Animales , China , Femenino , Frecuencia de los Genes , Genes de Insecto , Hemípteros/fisiología , Desequilibrio de Ligamiento , Modelos Genéticos , Datos de Secuencia Molecular , Fenotipo , Polimorfismo de Nucleótido Simple
18.
Langmuir ; 30(46): 13815-22, 2014 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-25358083

RESUMEN

Understanding the behavior of fluorocarbon surfactants at the air/water interface is crucial for many applications, such as lubricants, paints, cosmetics, and fire-fighting foams. In this study, molecular dynamics (MD) simulations were employed to investigate the microscopic properties of non-ionic fluorocarbon surfactants at the air/water interface. Several properties, including the distribution of head groups, the distribution probability of the tilt angle between hydrophobic tails with respect to the xy plane, and the order parameter of surfactants, were computed to probe the structure of hydrophobic surfactants at the air/water interface. The effects of the monomer structure on interfacial phenomena of non-ionic surfactants were investigated as well. It is observed that the structure of fluorocarbon surfactants at the air/water interface is more ordered than that of hydrocarbons, which is dominated by the van der Waals interaction between surfactants and water molecules. However, replacing one or two CF2 with one or two CH2 group does not significantly influence the interfacial structure, suggesting that hydrocarbons may be promising alternatives to perfluorinated surfactants.


Asunto(s)
Fluorocarburos/química , Simulación de Dinámica Molecular , Transición de Fase , Tensoactivos/química , Agua/química , Aire
19.
Colloids Surf B Biointerfaces ; 245: 114340, 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39476655

RESUMEN

In recent years, as a new type of quasi-zero-dimensional nanomaterials, graphene quantum dots (GQDs) have shown excellent performance in advanced drug targeted delivery and controlled release. In this work, the delivery process of model drugs translocating into POPC lipid membrane with the assistance of GQDs was investigated via molecular dynamics (MD) simulation. Our simulation results demonstrated that a single doxorubicin (DOX) or deoxyadenine (DA) molecule is difficult to penetrate into the cell membrane. GQD7 could form sandwich-like structure with DOX and assist DOX to enter into the POPC membrane. However, due to the weak interaction with DA, both GQD7 and GQD19 can not assist DA translocating the POPC membrane in the limited MD simulation time. The drug delivery process for DOX could be divided into two steps: 1. GQDs and DOX aggregated into a cluster; 2. the aggregates enter into the POPC membrane. In all our simulation systems, if GQDs loaded with model drugs and entered the cell membrane, it had little effect on the cell membrane structure, and the cell membrane could maintain high integrity and stability. These results may promote the molecular design and application of GQD-based drug delivery systems.

20.
J Control Release ; 376: 646-658, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39427774

RESUMEN

The advancement of rational nano drug delivery systems offers robust tools for achieving synergistic therapeutic outcomes in tumor treatment. In this study, we present the development of pH and near-infrared laser dual-responsive nanoparticles (DOX-CuS@CaCO3@PL-PEG, DCCP NPs) based on calcium carbonate, utilizing a one-pot gas diffusion reaction. These nanoparticles enable combined photothermal therapy (PTT), chemodynamic therapy (CDT), chemotherapy, and Ca2+-overloading synergistic therapy. Doxorubicin (DOX) and copper sulfide (CuS) NPs were co-loaded in CaCO3, followed by PEG surface functionalization. The presence of PEG enhanced the stability of DCCP NPs in aqueous environments. Controlled release of DOX, CuS NPs, and Ca2+ occurs specifically in the acidic tumor microenvironment. Released DOX enhances chemotherapy efficiency, while CuS NPs, upon laser irradiation, induce thermal damage, promoting further drug release and cellular uptake. Additionally, CuS NPs in our system consume excess GSH and generate toxic hydroxyl radicals (·OH) through a Fenton-like reaction, contributing to CDT. These radicals not only directly eliminate tumor cells but also disrupt mitochondrial Ca2+ buffering capacity. Furthermore, Ca2+ released from CaCO3 induces Ca2+-overloading, intensifying mitochondrial disruption and oxidative damage. The synergistic combination of PTT, CDT, chemotherapy, and Ca2+-overloading showcases significant therapeutic potential, indicating broad applications in tumor therapy. This multifaceted approach holds promise for advancing the field of tumor therapeutics.

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