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1.
Folia Primatol (Basel) ; 86(5): 446-54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26575480

RESUMO

This study analyzed conflict and postconflict (PC) conciliation between males and females within one-male breeding units in Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in the Qinling Mountains, China. The PC matched-control and time rule methods were used to collect and analyze data recorded from September 2013 to June 2014. The conciliatory tendency among individuals following conflict was 82.07%, and affiliation occurred within a few minutes after the conflict, which was not significantly different between mating and nonmating seasons. The PC conciliation scenarios were different from those reported from captivity. Lumbar hold and grooming were the most common expressions in reconciliation. In addition, bystander affiliation was uniquely found, which may be associated with the more terrestrial locomotion of R. roxellana, compared with other colobines.


Assuntos
Colobinae/fisiologia , Comportamento Social , Animais , Comportamento Animal , China , Colobinae/psicologia , Conflito Psicológico , Feminino , Asseio Animal , Masculino , Estações do Ano
2.
Opt Express ; 19(21): 19919-24, 2011 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-21997000

RESUMO

Fresnel zone plates (450 nm thick Au, 25 nm outermost zone width) used as objective lenses in a full field transmission reached a spatial resolution better than 20 nm and 1.5% efficiency with 8 keV photons. Zernike phase contrast was also realized without compromising the resolution. These are very significant achievements in the rapid progress of high-aspect-ratio zone plate fabrication by combined electron beam lithography and electrodeposition.


Assuntos
Microscopia de Contraste de Fase/métodos , Eletroquímica/métodos , Elétrons , Desenho de Equipamento , Ouro/química , Lentes , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão/métodos , Dispositivos Ópticos , Óptica e Fotônica/métodos , Fótons , Raios X
3.
Opt Lett ; 36(7): 1269-71, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21479054

RESUMO

Since its invention in 1930, Zernike phase contrast has been a pillar in optical microscopy and more recently in x-ray microscopy, in particular for low-absorption-contrast biological specimens. We experimentally demonstrate that hard-x-ray Zernike microscopy now reaches a lateral resolution below 30 nm while strongly enhancing the contrast, thus opening many new research opportunities in biomedicine and materials science.


Assuntos
Microscopia/métodos , Animais , Linhagem Celular Tumoral , Técnicas de Cocultura , Ouro/química , Nanopartículas Metálicas , Camundongos , Poliestirenos/química , Raios X
4.
Langmuir ; 27(13): 8424-9, 2011 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-21630657

RESUMO

We describe a simple and effective method to obtain colloidal surface-functionalized Au nanoparticles. The method is primarily based on irradiation of a gold solution with high-flux X-rays from a synchrotron source in the presence of 11-mercaptoundecanoic acid (MUA). Extensive tests of the products demonstrated high colloidal density as well as excellent stability, shelf life, and biocompatibility. Specific tests with X-ray diffraction, UV-visible spectrometry, visible microscopy, Fourier transform infrared spectroscopy, dark-field visible-light scattering microscopy, and transmission electron microscopy demonstrated that MUA, being an effective surfactant, not only allows tunable size control of the nanoparticles, but also facilitates functionalization. The nanoparticle sizes were 6.45 ± 1.58, 1.83 ± 1.21, 1.52 ± 0.37 and 1.18 ± 0.26 nm with no MUA and with MUA-to-Au ratios of 1:2, 1:1, and 3:1. The MUA additionally enabled functionalization with l-glycine. We thus demonstrated flexibility in controlling the nanoparticle size over a large range with narrow size distribution.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Coloides/química , Coloides/farmacologia , Relação Dose-Resposta a Droga , Ácidos Graxos/química , Ouro/farmacologia , Camundongos , Tamanho da Partícula , Relação Estrutura-Atividade , Compostos de Sulfidrila/química , Propriedades de Superfície
5.
Nanotechnology ; 22(6): 065605, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21212491

RESUMO

We synthesized AuPt alloyed nanoparticles in colloidal solution by a one-pot procedure based on synchrotron x-ray irradiation in the presence of PEG (polyethylene glycol). The exclusive presence of alloyed nanoparticles with fcc structure was confirmed by several different experiments including UV-vis spectroscopy, x-ray diffraction (XRD) and transmission electron microscopy (TEM). The composition of the AuPt alloyed nanoparticles can be varied in a continuous fashion by simply varying the feed ratios of Au and Pt precursors. The nanoparticles exhibited colloidal stability and biocompatibility, important for potential applications.

6.
Anal Bioanal Chem ; 401(3): 809-16, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21537916

RESUMO

Well-dispersed gold nanoparticles (NP) coated with tiopronin were synthesized by X-ray irradiation without reducing agents. High-resolution transmission electron microscopy shows that the average core diameters of the NPs can be systematically controlled by adjusting the tiopronin to Au mole ratio in the reaction. Three methods were used to study the NP uptake by cells: quantitative measurements by inductively coupled plasma mass spectrometry, direct imaging with high lateral resolution transmission electron microscopy and transmission X-ray microscopy. The results confirmed that the NP internalization mostly occurred via endocytosis and concerned the cytoplasm. The particles, in spite of their small sizes, were not found to arrive inside the cell nuclei. The synthesis without reducing agents and solvents increased the biocompatibility as required for potential applications in analysis and biomedicine in general.


Assuntos
Endocitose , Ouro/metabolismo , Nanopartículas Metálicas/química , Tiopronina/química , Sobrevivência Celular , Células/diagnóstico por imagem , Células/metabolismo , Células Cultivadas , Humanos , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Radiografia , Síncrotrons , Tiopronina/síntese química , Raios X
7.
J Nanobiotechnology ; 9: 14, 2011 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-21477355

RESUMO

BACKGROUND: Quantitative analysis of nanoparticle uptake at the cellular level is critical to nanomedicine procedures. In particular, it is required for a realistic evaluation of their effects. Unfortunately, quantitative measurements of nanoparticle uptake still pose a formidable technical challenge. We present here a method to tackle this problem and analyze the number of metal nanoparticles present in different types of cells. The method relies on high-lateral-resolution (better than 30 nm) transmission x-ray microimages with both absorption contrast and phase contrast -- including two-dimensional (2D) projection images and three-dimensional (3D) tomographic reconstructions that directly show the nanoparticles. RESULTS: Practical tests were successfully conducted on bare and polyethylene glycol (PEG) coated gold nanoparticles obtained by x-ray irradiation. Using two different cell lines, EMT and HeLa, we obtained the number of nanoparticle clusters uptaken by each cell and the cluster size. Furthermore, the analysis revealed interesting differences between 2D and 3D cultured cells as well as between 2D and 3D data for the same 3D specimen. CONCLUSIONS: We demonstrated the feasibility and effectiveness of our method, proving that it is accurate enough to measure the nanoparticle uptake differences between cells as well as the sizes of the formed nanoparticle clusters. The differences between 2D and 3D cultures and 2D and 3D images stress the importance of the 3D analysis which is made possible by our approach.


Assuntos
Endocitose/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Microtomografia por Raio-X/métodos , Apoptose , Linhagem Celular Tumoral , Ouro/administração & dosagem , Ouro/efeitos adversos , Humanos , Imageamento Tridimensional/métodos , Nanopartículas Metálicas/efeitos adversos , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão/métodos , Microscopia de Contraste de Fase/métodos , Polietilenoglicóis/química , Coloração e Rotulagem
8.
J Orthop Surg Res ; 16(1): 80, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482854

RESUMO

BACKGROUND: Only a few studies have described the effect of full arthroscopic surgery in treatment of excessive lateral pressure syndrome (ELPS). Therefore, the purpose of this study was to assess the clinical efficacy and experience of total arthroscopic lateral retinacular (LR) release and lateral patelloplasty for the treatment of ELPS. METHODS: A total of 73 patients (88 knees) with ELPS underwent arthroscopic LR release and lateral patelloplasty. The visual analogue scale (VAS), Kujala score, Lysholm scores, patella medial pushing distance, patellar tilt angle (PTA), and lateral patellofemoral angle (LPFA) were measured and evaluated before and after surgery. RESULTS: Follow-up ranged from 12 to 36 months with an average of 24 ± 5.8 months. The VAS was significantly lower at the last follow-up than before surgery (P < 0.01). The patella medial pushing distance, Kujala score, Lysholm score, PTA, and LPFA were significantly higher at the last follow-up than before surgery (P < 0.01, respectively). Years and lateral patella Outerbridge classification at the last follow-up have negative correlation with Kujala score, Lysholm score, Patella medial pushing distance, PTA, and LPFA (P < 0.01, respectively) and have positive correlation with VAS (P < 0.01, respectively). Related complications were not reported. CONCLUSIONS: Full arthroscopic LR release combined with lateral patelloplasty in the treatment of ELPS is an effective minimally invasive method, which can effectively correct anomalies of force line and skeleton of patella, relieve pain, and restore knee joint motor function with less complications.


Assuntos
Artroscopia/métodos , Patela/cirurgia , Articulação Patelofemoral/cirurgia , Síndrome da Dor Patelofemoral/cirurgia , Pressão , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
9.
Nanotechnology ; 21(33): 335604, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20657043

RESUMO

Monodisperse gold nanorods with high aspect ratio were synthesized by x-ray irradiation. Irradiation was first used to stimulate the creation of seeds. Afterward, nanorod growth was stimulated either by chemical reduction or again by x-ray irradiation. In the last case, the entire process took place without reducing agents. The shape of the final products could be controlled by modulating the intensity of the x-ray irradiation during the seed synthesis. In turn, the nanorod aspect ratio determines the absorption wavelength of the nanorods that can thus be optimized for different applications. Likewise, the aspect ratio influences the uptake of the nanorods by HeLa cells.


Assuntos
Materiais Biocompatíveis/química , Ouro/química , Nanotubos/química , Tamanho da Partícula , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacocinética , Ouro/farmacocinética , Células HeLa , Humanos , Microscopia Eletrônica de Transmissão , Nanotecnologia/métodos , Nitrato de Prata/química , Espectrofotometria Ultravioleta , Raios X
10.
Front Genet ; 11: 609414, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33408742

RESUMO

The genes of the major histocompatibility complex (MHC) are an important component of the vertebrate immune system and play a significant role in mate choice in many species. However, it remains unclear whether female mate choice in non-human primates is based on specific functional genes and/or genome-wide genes. The golden snub-nosed monkey (Rhinopithecus roxellana) lives in a multilevel society, which consists of several polygynous one-male-several-female units. Although adult females tend to mainly socialize with one adult male, females often initiate extra-pair copulations with other males resulting in a high proportion of offspring being fathered by extra-pair males. We investigated the effects of adaptive MHC genes and neutral microsatellites on female mate choice in a wild R. roxellana population. We sequenced 54 parent-offspring triads using two MHC class II loci (Rhro-DQA1 and Rhro-DQB1) and 20 microsatellites from 3 years of data. We found that the paternities of offspring were non-randomly associated with male MHC compositions not microsatellite genotypes. Our study showed that the fathers of all infants had significantly less variance for several estimates of genetic similarity to the mothers compared with random males at both MHC loci. Additionally, the MHC diversity of these fathers was significantly higher than random males. We also found support for choice based on specific alleles; compared with random males, Rhro-DQA1∗ 05 and Rhro-DQB1∗ 08 were more common in both the OMU (one-male unit) males and the genetic fathers of offspring. This study provides new evidence for female mate choice for MHC-intermediate dissimilarity (rather than maximal MHC dissimilarity) and highlights the importance of incorporating multiple MHC loci and social structure into studies of MHC-based mate choice in non-human primates.

11.
J Synchrotron Radiat ; 16(Pt 3): 395-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19395805

RESUMO

Dose measurements based on methylene blue (MB) bleaching, widely used for ultraviolet light, can also be applied to X-rays including very high flux levels. This method has been tested by using both MB bleaching and Fricke dosimetry for a conventional monochromatic X-ray source and then for 'white-beam' synchrotron radiation. The results show that MB bleaching dosimetry can easily measure X-ray doses up to at least 10(5) Gy s(-1), as long as the MB concentration is sufficiently high. This condition can be verified from the deviations from linearity of the bleaching versus exposure time.


Assuntos
Algoritmos , Radiometria/instrumentação , Radiometria/métodos , Síncrotrons/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Raios X
12.
Zool Res ; 40(2): 129-138, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30559334

RESUMO

Golden snub-nosed monkeys (Rhinopithecus roxellana), as typical arboreal group-living Old World monkeys, provide an appropriate animal model to research manual laterality and explore the factors affecting hand preference in nonhuman primates. This study investigated hand preference based on 63 subjects and four spontaneous manual tasks (including unimanual and bimanual feeding and grooming), and assessed the effects of age, gender and type of task on handedness in R. roxellana. A population-level left-handedness was found not only in the bimanual coordinated tasks (bimanual feeding and grooming), but also in one unimanual reaching task (unimanual feeding). There were no significant differences between the sexes in either direction or strength of hand preference among any task. However, a significant difference between adults and juveniles was found in the unimanual feeding task. This is the first report on handedness in unimanual and bimanual feeding tasks that require bipedal posture in wild R. roxellana. Furthermore, this study demonstrated spontaneous feeding tasks reported previously only in the quadrupedal posture in this species, supporting the importance of factors such as posture and task complexity in the evolution of primate manual lateralization.


Assuntos
Envelhecimento , Colobinae/fisiologia , Lateralidade Funcional/fisiologia , Animais , Feminino , Masculino , Fatores Sexuais
13.
Ying Yong Sheng Tai Xue Bao ; 30(2): 627-636, 2019 Feb 20.
Artigo em Zh | MEDLINE | ID: mdl-30915815

RESUMO

Land carrying capacity is one of the important research fields for land management and sustainable use. Urban-rural construction land is an essential component of land use type, the rationality of whose structure and layout is crucial to the sustainable use of land. Here, we executed the evaluation of the suitability of urban-rural construction land development, accounted the bearable critical threshold of urban-rural construction land, calculated the bearable abundance of urban-rural construction land, and compared with the current urban-rural construction land, analyzed the matching of the space layout, and then obtained the remaining development intensity of each county (city or district) of the Poyang Lake urban agglomeration. The results showed that the most suitable, more suitable, less suitable and unsuitable area about the evaluation results of urban-rural construction land development suitability were 3130.62, 2477.29, 867.03 and 29509.14 km2, respectively. The bearable critical threshold of urban-rural construction land (developable strength) was 16.6%, and the value of each county (city, district) was 7.7%-100%. The abundance of urban-rural construction land in each county (city, district) was mainly 0.15-1.30. The remaining development intensity was 12.3%, and the spatial matching degree was 0.76. The remaining develo-pment intensity of each county (city, district) was 4.9%-53.5%, and the spatial matching degree of each county (city, district) was 0.11- 1.00, with a wide range. Our results would help to clarify the relationship between the current development status and the rational development status, which could provide a basis for the refined management of urban-rural construction land and the regulatory policies' formulation of spatial pattern optimization.


Assuntos
Lagos , China , Cidades , Conservação dos Recursos Naturais
15.
Biotechnol Adv ; 31(3): 362-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22659216

RESUMO

An original synthesis method based on X-ray irradiation produced gold nanoparticles (AuNPs) with two important properties for biomedical research: intense visible photoluminescence and very high accumulation in cancer cells. The nanoparticles, coated with MUA (11-mercaptoundecanoid acid), are very small (1.4 nm diameter); the above two properties are not present for even slightly larger sizes. The small MUA-AuNPs are non-cytotoxic (except for very high concentrations) and do not interfere with cancer cell proliferation. Multimodality imaging using visible light fluorescence and X-ray microscopy is demonstrated by tracing the nanoparticle-loaded tumor cells.


Assuntos
Nanopartículas Metálicas/ultraestrutura , Animais , Proliferação de Células/efeitos dos fármacos , Ácidos Graxos , Ouro , Humanos , Luz , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Microscopia/métodos , Microscopia Eletrônica de Transmissão , Neoplasias Experimentais/diagnóstico , Neoplasias Experimentais/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Sulfidrila , Termogravimetria , Distribuição Tecidual , Células Tumorais Cultivadas , Raios X
16.
Biotechnol Adv ; 31(3): 396-401, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22193280

RESUMO

Complete profiling would substantially facilitate the fundamental understanding of tumor angiogenesis and of possible anti-angiogenesis cancer treatments. We developed an integrated synchrotron-based methodology with excellent performances: detection of very small vessels by high spatial resolution (~1 µm) and nanoparticle contrast enhancement, in vivo dynamics investigations with high temporal resolution (~1 ms), and three-dimensional quantitative morphology parametrization by computer tracing. The smallest (3-10 µm) microvessels were found to constitute >80% of the tumor vasculature and exhibit many structural anomalies. Practical applications are presented, including vessel microanalysis in xenografted tumors, monitoring the effects of anti-angiogenetic agents and in vivo detection of tumor vascular rheological properties.


Assuntos
Diagnóstico por Imagem/métodos , Microrradiografia/métodos , Microvasos/patologia , Neovascularização Patológica/diagnóstico , Algoritmos , Inibidores da Angiogênese/farmacologia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Sulfato de Bário , Bevacizumab , Meios de Contraste , Diagnóstico por Imagem/instrumentação , Humanos , Imageamento Tridimensional/métodos , Camundongos , Camundongos Endogâmicos BALB C , Microrradiografia/instrumentação , Microvasos/efeitos dos fármacos , Nanopartículas , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Síncrotrons , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Phys Med Biol ; 55(4): 931-45, 2010 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-20090183

RESUMO

Biocompatible Au nanoparticles with surfaces modified by PEG (polyethylene glycol) were developed in view of possible applications for the enhancement of radiotherapy. Such nanoparticles exhibit preferential deposition at tumor sites due to the enhanced permeation and retention (EPR) effect. Here, we systematically studied their effects on EMT-6 and CT26 cell survival rates during irradiation for a dose up to 10 Gy with a commercial biological irradiator (E(average) = 73 keV), a Cu-Kalpha(1) x-ray source (8.048 keV), a monochromatized synchrotron source (6.5 keV), a radio-oncology linear accelerator (6 MeV) and a proton source (3 MeV). The percentage of surviving cells after irradiation was found to decrease by approximately 2-45% in the presence of PEG-Au nanoparticles ([Au] = 400, 500 or 1000 microM). The cell survival rates decreased as a function of the dose for all sources and nanoparticle concentrations. These results could open the way to more effective cancer irradiation therapies by using nanoparticles with optimized surface treatment. Difficulties in applying MTT assays were also brought to light, showing that this approach is not suitable for radiobiology.


Assuntos
Compostos de Ouro , Nanopartículas Metálicas , Polietilenoglicóis , Radioterapia/métodos , Animais , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Coloides/química , Dano ao DNA/efeitos da radiação , Compostos de Ouro/química , Nanopartículas Metálicas/química , Camundongos , Polietilenoglicóis/química , Dosagem Radioterapêutica , Fatores de Tempo
19.
Phys Med Biol ; 55(2): 469-82, 2010 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-20023329

RESUMO

We investigated iron oxide nanoparticles with two different surface modifications, dextran coating and cross-linked dextran coating, showing that their different internalization affects their capability to enhance radiation damage to cancer cells. The internalization was monitored with an ultrahigh resolution transmission x-ray microscope (TXM), indicating that the differences in the particle surface charge play an essential role and dominate the particle-cell interaction. We found that dextran-coated iron oxide nanoparticles cannot be internalized by HeLa and EMT-6 cells without being functionalized with amino groups (the cross-linked dextran coating) that modify the surface potential from -18 mV to 13.4 mV. The amount of cross-linked dextran-coated iron oxide nanoparticles uptaken by cancer cells reached its maximum, 1.33 x 10(9) per HeLa cell, when the co-culture concentration was 40 microg Fe mL(-1) or more. Standard tests indicated that these internalized nanoparticles increased the damaging effects of x-ray irradiation, whereas they are by themselves biocompatible. These results could lead to interesting therapy applications; furthermore, iron oxide also produces high contrast for magnetic resonance imaging (MRI) in the diagnosis and therapy stages.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma/radioterapia , Carcinoma/terapia , Dextranos/uso terapêutico , Compostos Férricos/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Animais , Antineoplásicos/administração & dosagem , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Técnicas de Cocultura , Dextranos/administração & dosagem , Relação Dose-Resposta a Droga , Compostos Férricos/administração & dosagem , Células HeLa , Humanos , Nanopartículas Metálicas/administração & dosagem , Camundongos , Microscopia Eletrônica de Transmissão , Terapia por Raios X/métodos
20.
Nanotechnology ; 19(39): 395302, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21832591

RESUMO

The fabrication of devices to focus hard x-rays is one of the most difficult-and important-challenges in nanotechnology. Here we show that Fresnel zone plates combining 30 nm external zones and a high aspect ratio finally bring hard x-ray microscopy beyond the 30 nm Rayleigh spatial resolution level and measurable spatial frequencies down to 20-23 nm feature size. After presenting the overall nanofabrication process and the characterization test results, we discuss the potential research impact of these resolution levels.

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