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1.
Behav Brain Res ; 447: 114422, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37030546

RESUMO

BACKGROUND: Conduct disorder (CD) has been conceptualized as a psychiatric disorder associated with white-matter (WM) structural abnormalities. Although diffusion tensor imaging could identify WM structural architecture changes, it cannot characterize functional connectivity (FC) within WM. Few studies have focused on disentangling the WM dysfunctions in CD patients by using functional magnetic resonance imaging (fMRI). METHODS: The resting-state fMRI data were first obtained from both adolescent CD and typically developing (TD) controls. A voxel-based clustering analysis was utilized to identify the large-scale WM FC networks. Then, we examined the disrupted WM network features in CD, and further investigated whether these features could predict the impulsive symptoms in CD using support vector regression prediction model. RESULTS: We identified 11 WM functional networks. Compared with TDs, CD patients showed increased FCs between occipital network (ON) and superior temporal network (STN), between orbitofrontal network (OFN) and corona radiate network (CRN), as well as between deep network and CRN. Further, the disrupted FCs between ON and STN and between OFN and CRN were significantly negatively associated with non-planning impulsivity scores in CD. Moreover, the disrupted WM networks could be served as features to predict the motor impulsivity scores in CD. CONCLUSIONS: Our results provided further support on the existence of WM functional networks and could extended our knowledge about the WM functional abnormalities related with emotional and perception processing in CD patients from the view of WM dysfunction.


Assuntos
Transtorno da Conduta , Substância Branca , Humanos , Adolescente , Imagem de Tensor de Difusão/métodos , Transtorno da Conduta/diagnóstico por imagem , Transtorno da Conduta/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Imageamento por Ressonância Magnética/métodos , Emoções , Encéfalo
2.
Mol Pharm ; 20(6): 3234-3240, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37083400

RESUMO

Folic acid (FA) is a ligand that has been renowned for its strong binding to FA receptor (FR), and the robustness of the specific interaction has led to the generation of multitudinous tumor-targeted nano-drug delivery systems. However, selecting the appropriate FA targeted nano-drugs according to types of cancerous cells to achieve a high effect is critical. Understanding of how the drug is transported through the cell membrane and is delivered intracellularly is very important in screening ideal targeted nano-drugs for cancerous changes in different organs. Herein, by using a force tracing technique based on atomic force microscopy (AFM), the dynamic process of FA-polyamidoamine-Doxorubicin (FA-PAMAM-DOX) entry into different tumor cells (HeLa and A549) and normal cells (Vero) was monitored in real time. The cell membrane transport efficacy of FA-PAMAM-DOX in tumor cells with an FR high overexpression level (HeLa) and FR low overexpression level (A549) is analyzed, which is significantly higher than that in normal cells (Vero), especially for HeLa cells. Subsequently, the intracellular delivery efficiency of FA-PAMAM-DOX in different cell lines was measured by using fluorescence imaging and AFM-based nanoindentation techniques. This report will help to discover the cellular transport mechanism of nano-drugs and screen out optimal therapeutic nano-drugs for different types of tumors.


Assuntos
Sistemas de Liberação de Medicamentos , Ácido Fólico , Humanos , Células HeLa , Preparações Farmacêuticas , Ácido Fólico/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Doxorrubicina/farmacologia , Doxorrubicina/metabolismo , Linhagem Celular Tumoral
3.
Phys Chem Chem Phys ; 25(14): 9766-9771, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36946095

RESUMO

Transferrin (Tf) has been effectively used to promote the cellular uptake of HAIYPRH (T7) peptide-conjugated nano-drugs. In this study, the enhancing effect of Tf on T7-decorated nano-drug transport was investigated using force tracing and nano-indentation techniques at a single-particle/cell level. Furthermore, the results were confirmed by ensemble fluorescence imaging.


Assuntos
Peptídeos , Transferrina , Linhagem Celular Tumoral , Transporte Biológico , Sistemas de Liberação de Medicamentos
4.
J Craniofac Surg ; 34(4): 1226-1230, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36872515

RESUMO

OBJECTIVE: To investigate the clinicopathologic features, immunophenotype, molecular genetic changes, and differential diagnosis of cranial fasciitis (CF). METHODS: The clinical manifestations, imaging, surgical technique, pathologic characteristics, special staining, and immunophenotype, as well as break-apart fluorescence in situ hybridization assay for USP6 of 19 CF cases were analyzed, retrospectively. RESULTS: The patients were 11 boys and 8 girls, aged 5 to 144 months, with a median age of 29 months. There were 5 cases (26.31%) in the temporal bone, 4 cases (21.05%) in the parietal bone, 3 cases (15.78%) in the occipital bone, 3 cases (15.78%) in the frontotemporal bone, 2 cases (10.52%) in the frontal bone, 1 case (5.26%) in the mastoid of middle ear, and 1 case (5.26%) in the external auditory canal. The main clinical manifestations were painless, with the presentation of masses that grew rapidly and frequently eroded the skull. There was no recurrence and no metastasis after the operation. Histologically, the lesion consists of spindle fibroblasts/myofibroblasts arranged in bundles, braided or atypical spokes. Mitotic figures could be seen, but not atypical forms. Immunohistochemical studies showed diffuse strong positive SMA and Vimentin in all CFs. These cells were negative for Calponin, Desmin, ß-catenin, S-100, and CD34. The ki-67 proliferation index was 5% to 10%. Ocin blue-PH2.5 staining showed blue-stained mucinous features in the stroma. The positive rate of USP6 gene rearrangement detected by fluorescence in situ hybridization assay was about 10.52%, and the positive rate was not related to age. All patients were observed for 2 to 124 months and showed no signs of recurrence or metastasis. CONCLUSIONS: In summary, CF was a benign pseudosarcomatous fasciitis that occurs in the skull of infants. Preoperative diagnosis and differential diagnosis were difficult. Computed tomography typing might be beneficial for imaging diagnosis, and pathologic examination might be the most reliable way to diagnose CF.


Assuntos
Fasciite , Fibroma , Masculino , Lactente , Feminino , Humanos , Pré-Escolar , Hibridização in Situ Fluorescente , Estudos Retrospectivos , Fibroma/patologia , Proteínas S100 , Fasciite/diagnóstico por imagem , Fasciite/genética , Ubiquitina Tiolesterase/genética
5.
Fetal Pediatr Pathol ; 42(4): 545-556, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36734681

RESUMO

Objective: To investigate the clinicopathological features of children with Sturge-Weber syndrome and to analyze the correlation between the distribution area of leptomeningeal angiomatosis, the degree of cerebral cortical calcification, and the degree of cerebral atrophy associated with epileptic seizures. Methods: 10 children were diagnosed with SWS with FCD IIIc by histopathology and immunohistochemistry. Spearman correlation analysis was used to calculate the association of SWS with FCD IIIc and seizures in children. Results: The leptomeningeal angiomatosis area was markedly positively correlated with the degree of brain atrophy in 10 children with SWS (r = 0.783, p = 0.007). The distribution of leptomeningeal hemangiomatosis, the degree of cortical calcification, and brain atrophy were not significantly correlated with epilepsy. Conclusion: SWS may be accompanied by FCD IIIc. The more extensive the cerebral lobes of leptomeningeal angiomatosis in SWS, the more pronounced the brain atrophy.


Assuntos
Angiomatose , Epilepsia , Displasia Cortical Focal , Síndrome de Sturge-Weber , Criança , Humanos , Síndrome de Sturge-Weber/complicações , Síndrome de Sturge-Weber/diagnóstico , Síndrome de Sturge-Weber/patologia , Convulsões/etiologia , Angiomatose/complicações , Angiomatose/diagnóstico , Atrofia/complicações
6.
Comput Math Methods Med ; 2022: 5691099, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277015

RESUMO

Medical image fusion technology can integrate complementary information from different modality medical images to provide a more complete and accurate description of the specific diagnosed object, which is very helpful for image-guided clinical diagnosis and treatment. This paper proposes an effective brain image fusion framework based on improved rolling guidance filter (IRGF). Firstly, input images are decomposed into base layers and detail layers using the IRGF and Wiener filter. Secondly, the visual saliency maps of the input image are computed by pixel-level saliency value, and the weight maps of detail layers are constructed by max-absolute strategy and are further smoothed with Gaussian filter, the purpose of which is to make the fused image appear more naturally and more suitable for human visual perception. Lastly, base layers are fused by visual saliency map based fusion rule and the corresponding weight maps from detail layers are fused by the weighted least squares optimization scheme. Experimental results testify that our method is superior to some state-of-the-art methods in both subjective and objective assessments.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Encéfalo/diagnóstico por imagem , Distribuição Normal
7.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142189

RESUMO

Migratory birds spend several months in their breeding grounds in sympatry with local resident birds and relatively shorter periods of time at stopover sites. During migration, parasites may be transmitted between migratory and resident birds. However, to what extent they share these parasites remains unclear. In this study, we compared the assemblages of haemosporidian parasites in migratory, resident, and passing birds, as well as the correlations between parasite assemblages and host phylogeny. Compared with passing birds, migratory birds were more likely to share parasites with resident birds. Shared lineages showed significantly higher prevalence rates than other lineages, indicating that common parasites are more likely to spill over from the current host to other birds. For shared lineages, the prevalence was significantly higher in resident birds than in migratory birds, suggesting that migratory birds pick up parasites at their breeding ground. Among the shared lineages, almost two-thirds presented no phylogenetic signal in their prevalence, indicating that parasite transmission among host species is weakly or not correlated with host phylogeny. Moreover, similarities between parasite assemblages are not correlated with either migration status or the phylogeny of hosts. Our results show that the prevalence, rather than host phylogeny, plays a central role in parasite transmission between migratory and resident birds in breeding grounds.


Assuntos
Doenças das Aves , Haemosporida , Parasitos , Plasmodium , Animais , Doenças das Aves/epidemiologia , Aves , Haemosporida/genética , Filogenia , Plasmodium/genética , Prevalência
8.
Nanoscale ; 14(25): 8919-8928, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35699091

RESUMO

The popularity of RNA nanoparticles (RNPs) has risen rapidly during the past decade due to the development of RNA nanotechnology. Understanding the fast dynamic process of cell entry and intracellular delivery of RNPs is essential for the design of intelligent therapeutic RNA nano-drugs and mRNA vaccines.How the interaction between the membrane and target ligand of RNPs influences the cell entry, and how the dynamic mechanism of RNPs takes place in different organelles remain ill-defined. Herein, the cell entry of Antimir21-RNP-Apt is monitored using a force tracing technique with a high spatiotemporal resolution at the single particle level, the specific interaction of Apt and EGFR promotes the cell entry efficiency and achieves long-lasting curative effects. Furthermore, the intracellular delivery pathway through different organelles is discovered using fluorescence tracking, and the low motility in early endosomes and the high motility in late endosomes are analyzed. This report provides key strategies for engineering RNA nanomedicines and facilitating clinical translation.


Assuntos
Nanopartículas , RNA , Endossomos/metabolismo , Nanomedicina/métodos , Nanopartículas/metabolismo , Preparações Farmacêuticas , RNA/metabolismo
9.
J Hazard Mater ; 436: 128983, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35525216

RESUMO

Ultrathin fibers can increase the contact area between adsorbents and seawater during the uranium extraction process; however, their construction usually aggravates the complex spinning technology and lowers their mechanical strength. Meanwhile, high strength and antifouling ability are essential for ocean adsorbents to withstand the complex natural environment and microbial systems. Herein, we design high-strength and anti-biofouling poly(amidoxime) nanofiber membranes (HA-PAO NFMs) via a supramolecular crosslinking. Bacterial cellulose supplies the NFMs with ultrathin fiber structure, and large amounts of adsorption ligands are immobilized on the framework via the crosslinking with antibacterial ions. Thus, different from other fibers, HA-PAO NFMs achieve ultrathin diameter (20-30 nm), high BET area (51 m2 g-1), and excellent mechanical strength (13.6 MPa). The uranium adsorption capacity reaches to 409 mg-U/g-Ads in the simulated seawater, 99.2% uranium can be removed from the U-contained wastewater, and the adsorption process can be observed by the naked eye due to the significant color changes. The inhibition zones indicate their excellent anti-biofouling ability, which contributes to 1.83 times more uranium extraction amount from natural seawater than the non-antifouling adsorbents. Furthermore, they display a long service life and can be large-scale prepared, and the HA-PAO NFMs have potential in the massive uranium recovery.


Assuntos
Incrustação Biológica , Nanofibras , Urânio , Adsorção , Incrustação Biológica/prevenção & controle , Nanofibras/química , Água do Mar/química , Urânio/química , Águas Residuárias
10.
Chem Res Chin Univ ; 38(3): 838-842, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35530119

RESUMO

The rabies virus is a neurotropic virus that causes fatal diseases in humans and animals. Although studying the interactions between a single rabies virus and the cell membrane is necessary for understanding the pathogenesis, the internalization dynamic mechanism of single rabies virus in living cells remains largely elusive. Here, we utilized a novel force tracing technique based on atomic force microscopy(AFM) to record the process of single viral entry into host cell. We revealed that the force of the rabies virus internalization distributed at (65±25) pN, and the time was identified by two peaks with spacings of (237.2±59.1) and (790.3±134.4) ms with the corresponding speed of 0.12 and 0.04 µm/s, respectively. Our results provide insight into the effects of viral shape during the endocytosis process. This report will be meaningful for understanding the dynamic mechanism of rabies virus early infection. Electronic Supplementary Material: Supplementary material is available in the online version of this article at 10.1007/s40242-022-2069-y.

11.
Nanotechnology ; 33(28)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35320792

RESUMO

The potential of converting traditional biomass into low-cost HER catalysts has broad application prospects. In this paper, fungus is used as a carbon-based carrier. The bimetallic catalyst RuM-C (M = V, Mo, W, Zn, Cu) was synthesized under inert gas protection at high temperature. The order of electrocatalytic activity is RuV-C > RuZn-C > RuW-C > RuMo-C > Ru-C > RuCu-C > BF-C, which indicates that RuV-C exhibits excellent HER activity. Due to its irregular sheet structure, the specific surface area of the catalyst is increased. Impressively, it exhibits extremely high catalytic activity for HER in 1 M KOH due to favorable kinetics and excellent specific activity. Consequently, the prepared RuV-C exhibited excellent and stable HER activity compared Ru-C with a low overpotential of 65.78 mV at the current densities of 10 mA cm-2and Tafel slope of 45.26 mV dec-1. The potential only decreased by 88 mV after 24 h of continuous testing, which indicates that the catalyst has outstanding stability. This work will provide positive inspiration for the promotion of a new Ru-based biomass HER electrocatalyst.

12.
Int J Parasitol Parasites Wildl ; 15: 177-183, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34141566

RESUMO

The diversity of waterbirds is threatened, and haemosporidian parasite infection is considered one of the most important causative factors. However, to date, only a few studies focusing on specific parasite species have been carried out, which cannot reflect the general patterns at the community level. To test whether the reported haemosporidian diversity in waterbirds is underestimated, we estimated the prevalence and lineage diversity of avian haemosporidian parasites in 353 waterbirds from 26 species in the Tumuji National Nature Reserve, Northeast China, as well as the host-parasite associations. According to the molecular analysis of cytochrome b (cyt b) barcode sequences, 28.3% of the birds were infected by 49 distinct parasite lineages, including 11 Plasmodium, 12 Haemoproteus, and 26 Leucocytozoon lineages, of which 39 were novel. The highest prevalence was contributed by Leucocytozoon (13.31%), followed by Plasmodium (13.03%) and Haemoproteus (4.25%), which suggested that waterbirds were infected to a lesser extent by Haemoproteus than by the other two genera. Among the most sampled birds, species belonging to Anatidae appeared to be susceptible to Leucocytozoon but resistant to Plasmodium, while Rallidae presented the opposite pattern. On the phylogenetic tree, most of the Leucocytozoon lineages detected in Anatidae clustered together and formed two well-supported clades, while lineages restricted to Gruidae were distantly related to other parasites in all three genera. SW5 was the most abundant lineage and therefore might be a major threat to waterbirds; among the hosts, the common coot harboured the highest diversity of parasite lineages and thus could act as a reservoir for potential transmission. This is the first study of avian haemosporidian infections in a wild waterbird community in Asia. Our findings have doubled the number of lineages recorded in waterbirds, broadened our understanding of host-parasite associations, and addressed the importance of studying haemosporidian infections in wild waterbird conservation.

13.
Front Oncol ; 11: 647352, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34168984

RESUMO

As a research hotspot, circular RNAs (circRNAs) is one type of non-coding RNAs which have many different functions in biological processes. However, there is lack of study investigating the underlying molecular mechanism and the potential roles of circRNAs in Wilms tumor. We conducted a high-throughput microarray sequencing to screen differentially expressed circRNAs in Wilms tumor. A novel circRNA (circ0093740) was identified as a frequently upregulated circRNA in Wilms tumor cells and tissues. Suppression of circ0093740 remarkably inhibited the proliferation and migration ability in Wilms tumor, validated by several experiments. The molecular mechanism of circ0093740 was investigated by luciferase assays and RNA immunoprecipitation assays. The results revealed that circ0093740 promotes the growth and migration ability by sponging miR-136/145 and upregulating DNMT3A. In conclusion, our study discovered the biological role of the circ0093740-miR-136/145-DNMT3A axis in Wilms tumor growth and metastasis which is important for developing new treatment strategy.

14.
Neuropsychologia ; 157: 107865, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-33894243

RESUMO

Conduct disorder (CD) is a psychiatric condition characterized by severe aggressive and antisocial behaviors. Prior neuroimaging work reported that CD is associated with abnormal resting-state local intrinsic brain activity (IBA). However, few studies detected the time-varying brain activity patterns in CD. In this study, eighteen adolescent patients with CD and 18 typically developing controls underwent resting-state functional magnetic resonance imaging scans. We then compared the dynamic characteristics of IBA by calculating the dynamic regional homogeneity (dReHo) through a sliding-window approach between the two groups, and the correlations between the dReHo variability and clinical symptoms in CD were further examined. Moreover, the statistical between-group differences in dReHo were selected as classification features to help distinguish CD patients from controls by adopting a linear support vector machine (SVM) classifier. CD patients showed increased dReHo variability in the left precuneus, right postcentral gyrus, right precentral gyrus, left middle cingulate gyrus, and left paracentral lobule compared to controls, and dReHo variability in the left precuneus was significantly positively associated with impulsiveness scores in CD patients. Importantly, SVM combined with the leave-one-out cross-validation method results demonstrated that 75% (p < 0.001) subjects were correctly classified with sensitivity of 61% and specificity of 89%. Our results provided the initial evidence that CD is characterized by abnormal dynamic IBA patterns, giving novel insights into the neuropathological mechanisms of CD. Further, our findings exhibited that the dReHo variability may distinguish CD patients from controls with high accuracy.


Assuntos
Transtorno da Conduta , Adolescente , Encéfalo/diagnóstico por imagem , Transtorno da Conduta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Lobo Parietal , Máquina de Vetores de Suporte
15.
Analyst ; 146(7): 2321-2329, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33623934

RESUMO

Guanine (G) oxidation products, such as 8-hydroxy-2'-deoxyguanosine (8-OHdG) and 8-oxo-guanine (8-OXOG), have been widely studied as promising biomarkers for DNA oxidative damage. In this work, we develop a new method to detect G oxidative products released from live cells after chromium (vi) ion or hydrogen peroxide treatments by using a glass nanopipette-based flexible gold nanoelectrode (fGNE). Specific response to G oxidative products with high sensitivity can be detected from the fGNE tip through integrated electrochemical measurements and surface-enhanced Raman spectroscopy. The fGNE apex can be positioned very close to the cell membrane noninvasively because of its high flexibility and nanoscale tip size. With the assistance of the electrophoretic force, the fGNEs can effectively collect and detect the G-derived DNA damage products released from individual cells in the cell culture medium with high sensitivity.


Assuntos
Dano ao DNA , Ouro , 8-Hidroxi-2'-Desoxiguanosina , Desoxiguanosina , Guanina , Oxirredução
16.
ACS Appl Mater Interfaces ; 13(7): 8832-8843, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33587587

RESUMO

The design and synthesis of low-cost and efficient bifunctional electrocatalysts for water splitting are critical and challenging. Hereby, a bimetallic phosphide embedded in a N and P co-doped porous carbon (FeCoP2@NPPC) material was synthesized by using sustainable biomass-derived N- and P-containing carbohydrates and non-noble metal salts as precursors. The obtained material exhibits good catalytic activities in hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and overall water splitting. The bimetallic alloy phosphide (FeCoP2) is the active site for electrocatalysis. Theoretical calculation indicates that the sub-layer Fe atoms and top-layer Co atoms in FeCoP2 exhibit a synergistic effect for enhanced electrocatalytic performance. The carbon matrix around the FeCoP2 can prevent the corrosion during the catalytic reactions. The hierarchically porous structure of the FeCoP2@NPPC material can promote the transfer of electrons and electrolyte, and increase the contact area of the active sites and electrolytes. N- and P-containing functionalities improve the wetting and conductivity properties of the porous carbon. Due to the synergistic effects, FeCoP2@NPPC requires a low overpotential of 114 and 150 mV at the current density of 10 mA cm-2 for HER in 0.5 M H2SO4 and 1.0 M KOH, and an overpotential of 236 mV for OER in 1.0 M KOH solution, which are much lower than those of FeP@NPPC and CoP@NPPC. Based on the density functional theory calculation, FeCoP2 yields the smallest Gibbs free energy change of rate-determining step among the samples, which leads to better electrochemical performances. In addition, when FeCoP2@NPPC was used as a bifunctional catalyst in water splitting, the electrolyzer needed a low voltage of 1.60 V to deliver the current density of 10 mA cm-2. Furthermore, this work provides a strategy for preparing sustainable, stable, and highly active electrocatalysts for water splitting.

17.
Mol Pharm ; 18(3): 1480-1485, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33517655

RESUMO

The HAIYPRH (T7) peptide has been widely used as a ligand for constructing tumor-targeted nanodrug delivery systems since it can target the transferrin receptor (TfR) and then enter cells easily with the help of transferrin (Tf). However, the dynamic mechanism by which transferrin promotes the entry of T7-conjugated nanostructures into cells remains unclear. Herein, a force tracing technique based on atomic force microscopy (AFM) was used to track the ultrafast dynamic process of a T7-conjugated gold nanoparticle (AuNP-T7) entering a cell at the single-particle level in real time. Tf helped decrease the endocytosis force and increase the endocytosis speed of AuNP-T7 in A549 cells. However, Tf only increased the endocytosis speed of AuNP-T7 in HeLa cells. In contrast, in Vero cells without TfR overexpression, Tf decreased the endocytosis speed. This report provides important insights for redesigning and developing T7-conjugated nanodrug carriers in targeted nanodrug delivery systems.


Assuntos
Nanoestruturas/química , Peptídeos/metabolismo , Transferrina/metabolismo , Células A549 , Animais , Transporte Biológico/fisiologia , Linhagem Celular Tumoral , Chlorocebus aethiops , Sistemas de Liberação de Medicamentos/métodos , Endocitose/fisiologia , Ouro/metabolismo , Células HeLa , Humanos , Nanopartículas Metálicas/química , Receptores da Transferrina/metabolismo , Células Vero
18.
J Mater Chem B ; 9(4): 952-957, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33437980

RESUMO

A targeted nano-drug delivery system has provided great potential and benefits to the diagnosis and therapy of cancers. Cell entry is a critical step for taking effect of the targeted nano-drug. In this report, the dynamics of delivering a single aptamer targeted polyamindoamine-camptothecin-AS1411 (PAMAM-CPT-AS1411) nano-drug into cells was investigated using a force tracing technique based on atomic force microscopy. The results show that the specific interaction of AS1411 and nucleolin, which is overexpressed on cancer cells, enhances the efficiency of the PAMAM-CPT-AS1411 cell entry. Moreover, the specific interaction induced receptor-mediated endocytosis prolongs the duration and decreases the speed of a single PAMAM-CPT-AS1411 cell entry, which is helpful to understand the targeted nano-drugs prolonging the therapeutic drug level. However, the required force for PAMAM-CPT-AS1411 cell entry is not changed. This report will provide a novel and potential method for achieving the precise dynamics of targeted nano-drug delivery.


Assuntos
Aptâmeros de Nucleotídeos/química , Camptotecina/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Oligodesoxirribonucleotídeos/química , Poliaminas/química , Células A549 , Animais , Chlorocebus aethiops , Humanos , Estrutura Molecular , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície , Células Vero
19.
Parasit Vectors ; 13(1): 354, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32680557

RESUMO

BACKGROUND: Accurate quantification of infection intensity is essential to estimate infection patterns of avian haemosporidian parasites in order to understand the evolution of host-parasite associations. Traditional microscopy is cost-effective but requires high-quality blood smears and considerable experience, while the widely used semi-quantitative qPCR methods are mostly employed with ideal, laboratory-based golden samples and standard curves, which may limit the comparison of parasitemia from different laboratories. METHODS: Here we present a digital droplet PCR (ddPCR) protocol for absolute quantification of avian haemosporidians in raptors. Novel primers were designed that target a conserved fragment of a rRNA region of the mitochondrial genome of the parasites. Sensitivity and repeatability were evaluated compared to qPCR and other assays. RESULTS: This ddPCR assay enables accurate quantification of haemosporidian parasites belonging to Plasmodium, Haemoproteus and Leucocytozoon with minimum infection quantities of 10-5 (i.e. one parasite copy in 105 host genomes) without the use of standard curves. Quantities assessed by ddPCR were more accurate than qPCR using the same primers through reduction of non-specific amplification in low-intensity samples. The ddPCR technique was more consistent among technical duplicates and reactions, especially when infection intensities were low, and this technique demonstrated equal sensitivity with high correspondence (R2 = 0.97) compared to the widely used qPCR assay. Both ddPCR and qPCR identified more positive samples than the standard nested PCR protocol for the cytb gene used for barcoding avian haemosporidians. CONCLUSIONS: We developed a novel ddPCR assay enabling accurate quantification of avian haemosporidians without golden samples or standard curves. This assay can be used as a robust method for investigating infection patterns in different host-parasite assemblages and can facilitate the comparison of results from different laboratories.


Assuntos
Haemosporida/isolamento & purificação , Aves Predatórias/parasitologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Doenças das Aves/parasitologia , Aves , Genes de Protozoários , Haemosporida/genética , Patologia Molecular/métodos , Plasmodium/genética , Plasmodium/isolamento & purificação
20.
ACS Omega ; 5(17): 9864-9869, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32391473

RESUMO

Gold nanocages (Au NCs), as drug carriers, have been widely applied for cancer diagnosis and photothermal therapy (PTT). Transmembrane transporting efficacy of Au NCs is the fundamental and important issue for their use in PTT. Herein, we used a force tracing technique based on atomic force microscopy to track the dynamic transmembrane process of Au NCs at the single-particle level in real time. Meanwhile, we measured and compared the dynamic parameters of Au NCs with sizes of 50 and 100 nm usually used as nanodrug carriers of PTT. It is concluded that the 50 nm Au NC transmembrane transporting needs smaller force and shorter duration with a much faster speed. However, both the 50 and 100 nm Au NC transmembrane transporting depends on the caveolin-mediated endocytosis, clathrin-mediated endocytosis, and macropinocytosis, which was also confirmed by confocal fluorescence imaging. This report will provide a potential technique for screening nanodrug carriers from the perspective of transmembrane transporting efficacy.

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