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1.
J Nanobiotechnology ; 22(1): 22, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184620

RESUMO

The accurate preoperative diagnosis and tracking of lung adenocarcinoma is hindered by non-targeting and diffusion of dyes used for marking tumors. Hence, there is an urgent need to develop a practical nanoprobe for tracing lung adenocarcinoma precisely even treating them noninvasively. Herein, Gold nanoclusters (AuNCs) conjugate with thyroid transcription factor-1 (TTF-1) antibody, then multifunctional nanoprobe Au-TTF-1 is designed and synthesized, which underscores the paramount importance of advancing the machine learning diagnosis and bioimaging-guided treatment of lung adenocarcinoma. Bright fluorescence (FL) and strong CT signal of Au-TTF-1 set the stage for tracking. Furthermore, the high specificity of TTF-1 antibody facilitates selective targeting of lung adenocarcinoma cells as compared to common lung epithelial cells, so machine learning software Lung adenocarcinoma auxiliary detection system was designed, which combined with Au-TTF-1 to assist the intelligent recognition of lung adenocarcinoma jointly. Besides, Au-TTF-1 not only contributes to intuitive and targeted visualization, but also guides the following noninvasive photothermal treatment. The boundaries of tumor are light up by Au-TTF-1 for navigation, it penetrates into tumor and implements noninvasive photothermal treatment, resulting in ablating tumors in vivo locally. Above all, Au-TTF-1 serves as a key platform for target bio-imaging navigation, machine learning diagnosis and synergistic PTT as a single nanoprobe, which demonstrates attractive performance on lung adenocarcinoma.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Fluorescência , Terapia Fototérmica , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/tratamento farmacológico , Anticorpos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Tomografia Computadorizada por Raios X
2.
Curr Urol Rep ; 25(1): 19-35, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38099997

RESUMO

PURPOSE OF REVIEW: The aim of the systematic review is to assess AI's capabilities in the genetics of prostate cancer (PCa) and bladder cancer (BCa) to evaluate target groups for such analysis as well as to assess its prospects in daily practice. RECENT FINDINGS: In total, our analysis included 27 articles: 10 articles have reported on PCa and 17 on BCa, respectively. The AI algorithms added clinical value and demonstrated promising results in several fields, including cancer detection, assessment of cancer development risk, risk stratification in terms of survival and relapse, and prediction of response to a specific therapy. Besides clinical applications, genetic analysis aided by the AI shed light on the basic urologic cancer biology. We believe, our results of the AI application to the analysis of PCa, BCa data sets will help to identify new targets for urological cancer therapy. The integration of AI in genomic research for screening and clinical applications will evolve with time to help personalizing chemotherapy, prediction of survival and relapse, aid treatment strategies such as reducing frequency of diagnostic cystoscopies, and clinical decision support, e.g., by predicting immunotherapy response. These factors will ultimately lead to personalized and precision medicine thereby improving patient outcomes.


Assuntos
Próstata , Neoplasias da Bexiga Urinária , Masculino , Humanos , Recidiva Local de Neoplasia/genética , Inteligência Artificial , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/terapia , Recidiva , Biomarcadores
3.
Biomacromolecules ; 24(1): 86-97, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36512504

RESUMO

Spinal cord injury (SCI) generally leads to long-term functional deficits and is difficult to repair spontaneously. Many biological scaffold materials and stem cell treatment strategies have been explored, but very little research focused on the method of combining exogenous neural stem cells (NSCs) with a biodegradable conductive hydrogel scaffold. Here, a NSC loaded conductive hydrogel scaffold (named ICH/NSCs) was assembled by amino-modified gelatin (NH2-Gelatin) and aniline tetramer grafted oxidized hyaluronic acid (AT-OHA). Desirably, the well-conducting ICH/NSCs can be simply injected into the target site of SCI for establishing a good electrical signal pathway of cells, and the proper degradation cycle facilitates new nerve growth. In vitro experiments indicated that the inherent electroactive microenvironment of the hydrogel could better manipulate the differentiation of NSCs into neurons and inhibit the formation of glial cells and scars. Collectively, the ICH/NSC scaffold has successfully stimulated the recovery of SCI and may provide a promising treatment strategy for SCI repair.


Assuntos
Células-Tronco Neurais , Traumatismos da Medula Espinal , Humanos , Gelatina , Hidrogéis/metabolismo , Alicerces Teciduais , Traumatismos da Medula Espinal/terapia , Diferenciação Celular , Medula Espinal/metabolismo
4.
PLoS Comput Biol ; 17(7): e1009193, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34297718

RESUMO

Epithelial-mesenchymal transition (EMT) and its reverse process, mesenchymal-epithelial transition (MET), are believed to play key roles in facilitating the metastatic cascade. Metastatic lesions often exhibit a similar epithelial-like state to that of the primary tumour, in particular, by forming carcinoma cell clusters via E-cadherin-mediated junctional complexes. However, the factors enabling mesenchymal-like micrometastatic cells to resume growth and reacquire an epithelial phenotype in the target organ microenvironment remain elusive. In this study, we developed a workflow using image-based cell profiling and machine learning to examine morphological, contextual and molecular states of individual breast carcinoma cells (MDA-MB-231). MDA-MB-231 heterogeneous response to the host organ microenvironment was modelled by substrates with controllable stiffness varying from 0.2kPa (soft tissues) to 64kPa (bone tissues). We identified 3 distinct morphological cell types (morphs) varying from compact round-shaped to flattened irregular-shaped cells with lamellipodia, predominantly populating 2-kPa and >16kPa substrates, respectively. These observations were accompanied by significant changes in E-cadherin and vimentin expression. Furthermore, we demonstrate that the bone-mimicking substrate (64kPa) induced multicellular cluster formation accompanied by E-cadherin cell surface localisation. MDA-MB-231 cells responded to different substrate stiffness by morphological adaptation, changes in proliferation rate and cytoskeleton markers, and cluster formation on bone-mimicking substrate. Our results suggest that the stiffest microenvironment can induce MET.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , Aprendizado de Máquina , Modelos Biológicos , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/fisiopatologia , Adaptação Fisiológica , Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Fenômenos Biofísicos , Caderinas/metabolismo , Adesão Celular/fisiologia , Contagem de Células , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Forma Celular/fisiologia , Biologia Computacional , Matriz Extracelular/patologia , Matriz Extracelular/fisiologia , Feminino , Humanos , Metástase Neoplásica/patologia , Metástase Neoplásica/fisiopatologia , Microambiente Tumoral/fisiologia , Vimentina/metabolismo
5.
Macromol Rapid Commun ; 43(10): e2200034, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35332623

RESUMO

Cancer remains a formidable global problem with a high mortality rate. There are many effective anti-cancer drugs in clinical use, among which paclitaxel (PTX) has good effects on non-small cell lung cancer, ovarian cancer, and breast cancer. However, when applied to the clinic, PTX still has many limitations, such as poor water solubility, drug resistance, and side effects on healthy tissues. A gold nanodots-paclitaxel-polylysine (AuNDs-PTX-PLL) core-shell nano-system of integrated diagnosis and treatment is constructed to achieve intelligent responsive drug delivery. On the one hand, the problem of poor water-solubility and drug resistance of PTX are solved. On the other hand, the nano-system has an excellent intelligent response effect. Drugs can only be released in the weakly acidic environment of the tumor, which reduces the damage and side effects to normal tissues. Moreover, the nano-system can be used for real-time tracking and auxiliary diagnosis for the tumor through the multi-mode imaging mode, such as fluorescence, photoacoustic, and computed tomography to achieve accurate visualization. The photothermal effect of AuNDs is beneficial to promote the release of drugs. The nano-system integrates multi-mode imaging, chemotherapy, intelligent drug release in tumor weakly acidic environment, and has excellent practical application prospects in tumor diagnosis and treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Ouro , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Água
6.
Macromol Rapid Commun ; 42(20): e2100362, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34435714

RESUMO

The treatment of large segmental bone defects and complex types of fractures caused by trauma, inflammation, or tumor resection is still a challenge in the field of orthopedics. Various natural or synthetic biological materials used in clinical applications cannot fully replicate the structure and performance of raw bone. This highlights how to endow materials with multiple functions and biological properties, which is a problem that needs to be solved in practical applications. Hydrogels with outstanding biocompatibility, for their casting into any shape, size, or form, are suitable for different forms of bone defects. Therefore, they have been used in regenerative medicine more widely. In this review, versatile hydrogels are compounded with nanoparticles of different dimensions, and many desirable features of these materials in bone regeneration are introduced, including drug delivery, cell factor vehicle, cell scaffolds, which have potential in bone regeneration applications. The combination of hydrogels and nanoparticles of different dimensions encourages better filling of bone defect areas and has higher adaptability. This is due to the minimally invasive properties of the material and ability to match irregular defects. These biological characteristics make composite hydrogels with different dimensional nanoparticles become one of the most attractive options for bone regeneration materials.


Assuntos
Hidrogéis , Nanopartículas , Materiais Biocompatíveis , Regeneração Óssea , Engenharia Tecidual
7.
Proc Natl Acad Sci U S A ; 115(39): 9690-9695, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30194234

RESUMO

We report combined therapy using upconversion nanoparticles (UCNP) coupled to two therapeutic agents: beta-emitting radionuclide yttrium-90 (90Y) fractionally substituting yttrium in UCNP, and a fragment of the exotoxin A derived from Pseudomonas aeruginosa genetically fused with a targeting designed ankyrin repeat protein (DARPin) specific to HER2 receptors. The resultant hybrid complex UCNP-R-T was tested using human breast adenocarcinoma cells SK-BR-3 overexpressing HER2 receptors and immunodeficient mice, bearing HER2-positive xenograft tumors. The photophysical properties of UCNPs enabled background-free imaging of the UCNP-R-T distribution in cells and animals. Specific binding and uptake of UCNP complexes in SK-BR-3 cells was observed, with separate 90Y- and PE40-induced cytotoxic effects characterized by IC50 140 µg/mL (UCNP-R) and 5.2 µg/mL (UCNP-T), respectively. When both therapeutic agents were combined into UCNP-R-T, the synergetic effect increased markedly, ∼2200-fold, resulting in IC50 = 0.0024 µg/mL. The combined therapy with UCNP-R-T was demonstrated in vivo.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Endotoxinas/uso terapêutico , Nanopartículas/uso terapêutico , Nanotecnologia/métodos , Neoplasias/terapia , Radioterapia/métodos , Adenocarcinoma/terapia , Repetição de Anquirina , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias/diagnóstico por imagem , Pseudomonas aeruginosa , Cintilografia/métodos , Receptor ErbB-2/metabolismo , Proteínas Recombinantes , Radioisótopos de Ítrio/uso terapêutico
8.
Int J Urol ; 28(12): 1290-1297, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34498294

RESUMO

OBJECTIVES: To investigate whether anti-glypican-1 antibody Miltuximab conjugated with near-infrared dye IRDye800CW can be used for in vivo fluorescence imaging of urothelial carcinoma. METHODS: The conjugate, Miltuximab-IRDye800CW, was produced and characterized by size exclusion chromatography and flow cytometry with glypican-1-expressing cells. Balb/c nude mice bearing subcutaneous urothelial carcinoma xenografts were intravenously injected with Miltuximab-IRDye800CW or control IgG-IRDye800CW and imaged daily by fluorescence imaging. After 10 days, tumors and major organs were collected for ex vivo study of the conjugate biodistribution, including its accumulation in the tumor. RESULTS: The intravenous injection of Miltuximab-IRDye800CW to tumor-bearing mice showed its specific accumulation in the tumors with the tumor-to-background ratio of 12.7 ± 2.4, which was significantly higher than that in the control group (4.6 ± 0.9, P < 0.005). The ex vivo imaging was consistent with the in vivo findings, with tumors from the mice injected with Miltuximab-IRDye800CW being significantly brighter than the organs or the control tumors. CONCLUSIONS: The highly specific accumulation and retention of Miltuximab-IRDye800CW in glypican-1-expressing tumors in vivo shows its high potential for fluorescence imaging of urothelial carcinoma and warrants its further investigation toward clinical translation.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Animais , Linhagem Celular Tumoral , Glipicanas , Camundongos , Camundongos Nus , Imagem Molecular , Imagem Óptica , Distribuição Tecidual , Neoplasias da Bexiga Urinária/diagnóstico por imagem
9.
Int J Mol Sci ; 22(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34830253

RESUMO

Zinc oxide nanoparticle (ZnO NP)-based sunscreens are generally considered safe because the ZnO NPs do not penetrate through the outermost layer of the skin, the stratum corneum (SC). However, cytotoxicity of zinc ions in the viable epidermis (VE) after dissolution from ZnO NP and penetration into the VE is ill-defined. We therefore quantified the relative concentrations of endogenous and exogenous Zn using a rare stable zinc-67 isotope (67Zn) ZnO NP sunscreen applied to excised human skin and the cytotoxicity of human keratinocytes (HaCaT) using multiphoton microscopy, zinc-selective fluorescent sensing, and a laser-ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) methodology. Multiphoton microscopy with second harmonic generation imaging showed that 67ZnO NPs were retained on the surface or within the superficial layers of the SC. Zn fluorescence sensing revealed higher levels of labile and intracellular zinc in both the SC and VE relative to untreated skin, confirming that dissolved zinc species permeated across the SC into the VE as ionic Zn and significantly not as ZnO NPs. Importantly, the LA-ICP-MS estimated exogenous 67Zn concentrations in the VE of 1.0 ± 0.3 µg/mL are much lower than that estimated for endogenous VE zinc of 4.3 ± 0.7 µg/mL. Furthermore, their combined total zinc concentrations in the VE are much lower than the exogenous zinc concentration of 21 to 31 µg/mL causing VE cytotoxicity, as defined by the half-maximal inhibitory concentration of exogenous 67Zn found in human keratinocytes (HaCaT). This speaks strongly for the safety of ZnO NP sunscreens applied to intact human skin and the associated recent US FDA guidance.


Assuntos
Epiderme/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Protetores Solares/farmacologia , Óxido de Zinco/farmacologia , Abdominoplastia/métodos , Administração Cutânea , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Epiderme/ultraestrutura , Feminino , Fluoresceínas/química , Corantes Fluorescentes/química , Humanos , Queratinócitos/citologia , Queratinócitos/ultraestrutura , Nanopartículas Metálicas/ultraestrutura , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Pessoa de Meia-Idade , Nanopartículas/administração & dosagem , Nanopartículas/ultraestrutura , Quinolonas/química , Absorção Cutânea/fisiologia , Compostos de Tosil/química
10.
Molecules ; 25(18)2020 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-32961731

RESUMO

Theranostic approach is currently among the fastest growing trends in cancer treatment. It implies the creation of multifunctional agents for simultaneous precise diagnosis and targeted impact on tumor cells. A new type of theranostic complexes was created based on NaYF4: Yb,Tm upconversion nanoparticles coated with polyethylene glycol and functionalized with the HER2-specific recombinant targeted toxin DARPin-LoPE. The obtained agents bind to HER2-overexpressing human breast adenocarcinoma cells and demonstrate selective cytotoxicity against this type of cancer cells. Using fluorescent human breast adenocarcinoma xenograft models, the possibility of intravital visualization of the UCNP-based complexes biodistribution and accumulation in tumor was demonstrated.


Assuntos
Nanopartículas Metálicas/química , Nanomedicina Teranóstica , Animais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Corantes Fluorescentes/química , Fluoretos/química , Humanos , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/toxicidade , Camundongos , Camundongos Nus , Polietilenoglicóis/química , Receptor ErbB-2/metabolismo , Túlio/química , Transplante Heterólogo , Itérbio/química , Ítrio/química
11.
Appl Opt ; 55(21): 5554-63, 2016 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-27463904

RESUMO

A retroemission device (REM) is an incoherent holographic device that represents a lenslet array situated on a substrate containing fluorescent material. Each lenslet focuses each wavelet of an optical wavefront incident on the REM device into a diffraction-limited volume (voxel) in the fluorescent material, so that the voxel coordinates encode the angle of incidence and curvature of the wavelet. The back-propagating fraction of the excited fluorescence is collected by the lenslet and quasi-collimated into a back-propagating wavelet. All wavelets are combined to reconstruct the incident wavefront propagating in the backward direction. We present a theoretical model of REM based on Fresnel-Kirchhoff approximation describing the reconstructed 3D image characteristics versus the thickness of the fluorescence film at the focal plane of the lenslets. Results of the computer simulations of the REM-based images of a point source, two axially separated point sources and an extended object (a circular rim) situated in the sagittal plane are presented. These results speak in favor of using a fluorescence film of minimum diffraction-limited thickness at the lenslet back focal plane. This REM structure minimizes the fluorescence background and improves the 3D imaging resolution in virtue of the exclusion of out-of-voxel fluorescence contributions to the reconstructed wavefront.

12.
Opt Lett ; 40(7): 1169-72, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25831284

RESUMO

This Letter addresses wavefront reconstruction by a retroemission device (REM). REM represents a lenslet array mounted on a substrate made of photoluminescent optical material, such as a polymer film impregnated with upconversion nanoparticles. An excitation light wavefront incident on the REM was sampled by the lenslet array piece-wise. Each wavelet at the lenslet aperture was converged into a voxel in the substrate, with its coordinates encoding the angle of incidence and curvature of the wavelet. Photoluminescence excited in the voxel was radiated isotropically, its back-propagating fraction was captured by the lenslet and transformed into a back-propagating wavelet, which contributed to reproduction of the entire incident wavefront with some fidelity. We experimentally proved the wavefront reconstruction based on REM, and present its theoretical model based on a Fresnel-Kirchhoff approximation.

13.
Int J Mol Sci ; 17(1)2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26729091

RESUMO

Targeted radionuclide therapy is one of the most intensively developing directions of nuclear medicine. Unlike conventional external beam therapy, the targeted radionuclide therapy causes less collateral damage to normal tissues and allows targeted drug delivery to a clinically diagnosed neoplastic malformations, as well as metastasized cells and cellular clusters, thus providing systemic therapy of cancer. The methods of targeted radionuclide therapy are based on the use of molecular carriers of radionuclides with high affinity to antigens on the surface of tumor cells. The potential of targeted radionuclide therapy has markedly grown nowadays due to the expanded knowledge base in cancer biology, bioengineering, and radiochemistry. In this review, progress in the radionuclide therapy of hematological malignancies and approaches for treatment of solid tumors is addressed.


Assuntos
Neoplasias/radioterapia , Radioimunoterapia , Sistemas de Liberação de Medicamentos , Humanos
14.
Mol Pain ; 10: 12, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24521084

RESUMO

BACKGROUND: Somatostatin (SST) and some of its receptor subtypes have been implicated in pain signaling at the spinal level. In this study we have investigated the role of SST and its sst2A receptor (sst2A) in dorsal root ganglia (DRGs) and spinal cord. RESULTS: SST and sst2A protein and sst2 transcript were found in both mouse and human DRGs, sst2A-immunoreactive (IR) cell bodies and processes in lamina II in mouse and human spinal dorsal horn, and sst2A-IR nerve terminals in mouse skin. The receptor protein was associated with the cell membrane. Following peripheral nerve injury sst2A-like immunoreactivity (LI) was decreased, and SST-LI increased in DRGs. sst2A-LI accumulated on the proximal and, more strongly, on the distal side of a sciatic nerve ligation. Fluorescence-labeled SST administered to a hind paw was internalized and retrogradely transported, indicating that a SST-sst2A complex may represent a retrograde signal. Internalization of sst2A was seen in DRG neurons after systemic treatment with the sst2 agonist octreotide (Oct), and in dorsal horn and DRG neurons after intrathecal administration. Some DRG neurons co-expressed sst2A and the neuropeptide Y Y1 receptor on the cell membrane, and systemic Oct caused co-internalization, hypothetically a sign of receptor heterodimerization. Oct treatment attenuated the reduction of pain threshold in a neuropathic pain model, in parallel suppressing the activation of p38 MAPK in the DRGs CONCLUSIONS: The findings highlight a significant and complex role of the SST system in pain signaling. The fact that the sst2A system is found also in human DRGs and spinal cord, suggests that sst2A may represent a potential pharmacologic target for treatment of neuropathic pain.


Assuntos
Gânglios Espinais/patologia , Receptores de Somatostatina/metabolismo , Ciática/metabolismo , Ciática/patologia , Células Receptoras Sensoriais/metabolismo , Somatostatina/metabolismo , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Lateralidade Funcional/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Glutamato Descarboxilase/genética , Proteínas de Fluorescência Verde/deficiência , Proteínas de Fluorescência Verde/genética , Humanos , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Octreotida/uso terapêutico , Oligopeptídeos/farmacologia , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/genética , Receptores de Somatostatina/antagonistas & inibidores , Receptores de Somatostatina/deficiência , Receptores de Somatostatina/genética , Ciática/complicações , Ciática/tratamento farmacológico , Células Receptoras Sensoriais/efeitos dos fármacos , Somatostatina/genética
15.
Adv Sci (Weinh) ; 11(20): e2307060, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38516744

RESUMO

Biodegradable nanomaterials can significantly improve the safety profile of nanomedicine. Germanium nanoparticles (Ge NPs) with a safe biodegradation pathway are developed as efficient photothermal converters for biomedical applications. Ge NPs synthesized by femtosecond-laser ablation in liquids rapidly dissolve in physiological-like environment through the oxidation mechanism. The biodegradation of Ge nanoparticles is preserved in tumor cells in vitro and in normal tissues in mice with a half-life as short as 3.5 days. Biocompatibility of Ge NPs is confirmed in vivo by hematological, biochemical, and histological analyses. Strong optical absorption of Ge in the near-infrared spectral range enables photothermal treatment of engrafted tumors in vivo, following intravenous injection of Ge NPs. The photothermal therapy results in a 3.9-fold reduction of the EMT6/P adenocarcinoma tumor growth with significant prolongation of the mice survival. Excellent mass-extinction of Ge NPs (7.9 L g-1 cm-1 at 808 nm) enables photoacoustic imaging of bones and tumors, following intravenous and intratumoral administrations of the nanomaterial. As such, strongly absorbing near-infrared-light biodegradable Ge nanomaterial holds promise for advanced theranostics.


Assuntos
Germânio , Técnicas Fotoacústicas , Fototerapia , Animais , Camundongos , Técnicas Fotoacústicas/métodos , Germânio/química , Fototerapia/métodos , Modelos Animais de Doenças , Lasers , Nanopartículas/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Neoplasias/terapia , Neoplasias/diagnóstico por imagem , Feminino
16.
Proteomics ; 13(9): 1437-43, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23456920

RESUMO

High-affinity molecular pairs provide a convenient and flexible modular base for the design of molecular probes and protein/antigen assays. Specificity and sensitivity performance indicators of a bioassay critically depend on the dissociation constant (K(D)) of the molecular pair, with avidin:biotin being the state-of-the-art molecular pair (K(D) ∼ 1 fM) used almost universally for applications in the fields of nanotechnology and proteomics. In this paper, we present an alternative high-affinity protein pair, barstar:barnase (K(D) ∼ 10 fM), which addresses several shortfalls of the avidin:biotin system, including non-negligible background due to the non-specific binding. A quantitative assessment of the non-specific binding carried out using a model assay revealed inherent irreproducibility of the [strept]avidin:biotin-based assays, attributed to the avidin binding to solid phases, endogenous biotin molecules and serum proteins. On the other hand, the model assays assembled via a barstar:barnase protein linker proved to be immune to such non-specific binding, showing good prospects for high-sensitivity rare biomolecular event nanoproteomic assays.


Assuntos
Proteínas de Bactérias/metabolismo , Bioensaio/métodos , Proteômica/métodos , Ribonucleases/metabolismo , Anticorpos/genética , Avidina/metabolismo , Biotina/metabolismo , Escherichia coli/genética , Microscopia de Fluorescência , Análise Serial de Proteínas/métodos , Receptor ErbB-2/imunologia , Estreptavidina/metabolismo
17.
Small ; 9(1): 132-9, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23024073

RESUMO

Control over the quantum states of individual luminescent nitrogen-vacancy (NV) centres in nanodiamonds (NDs) is demonstrated by careful design of the crystal host: its size, surface functional groups, and interfacing substrate. By progressive etching of the ND host, the NV centres are induced to switch from latent, through continuous, to intermittent or "blinking" emission states. The blinking mechanism of the NV centre in NDs is elucidated and a qualitative model proposed to explain this phenomenon in terms of the centre electron(s) tunnelling to acceptor site(s). These measurements suggest that the substrate material and its proximity to the NV are responsible for the fluorescence intermittency.

18.
Exp Dermatol ; 22(7): 458-63, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23800056

RESUMO

Skin photoageing results from a combination of factors including ultraviolet (sun) exposure, leading to significant changes in skin morphology and composition. Conventional methods assessing the degree of photoageing, in particular histopathological assessment involve an invasive multistep process. Advances in microscopy have enabled a shift towards non-invasive in vivo microscopy techniques such as reflectance confocal microscopy (RCM) in this context. Computational image analysis of RCM images has the potential to be of use in the non-invasive assessment of photoageing. In this report, we computationally characterized a clinical RCM data set from younger and older Caucasians with varying levels of photoageing. We identified several mathematical relationships that related to the degree of photoageing as assessed by conventional scoring approaches (clinical photography, SCINEXA and RCM). Furthermore, by combining the mathematical features into a single computational assessment score, we observed significant correlations with conventional RCM (P < 0.0001) and the other clinical assessment techniques.


Assuntos
Processamento de Imagem Assistida por Computador , Microscopia Confocal/métodos , Envelhecimento da Pele , Neoplasias Cutâneas/diagnóstico , Adulto , Fatores Etários , Algoritmos , Automação , Feminino , Humanos , Luz , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Reconhecimento Automatizado de Padrão , Pele/patologia , Dermatopatias/diagnóstico , População Branca
19.
Talanta ; 256: 124255, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652761

RESUMO

The high incidence and complex subtypes of prostate cancer put forward higher requirements for accurate diagnosis. Furthermore, advanced prostate cancer is prone to metastasis. Single biological imaging mode faces a challenge of sensitive and fast bioimaging of metastasic prostate cancer. Thus, exploring a nanoprobe with multi-mode imaging function has an important impact on preoperative imaging and intraoperative visualization guide of metastatic prostate cancer. Herein, based on the optical properties and X-ray attenuation capability of Au nanodots as well as the slow electronic relaxation of Gd3+, we designed and fabricated the multifunctional nanoprobe Au/Gd nanodots for multi-mode imaging and accurate diagnosis of bone metastatic prostate cancer. The results showed that multiple imaging modes complement each other to achieve high-precision of metastasic prostate cancer detection and accurately guide treatment. In addition, in vitro/vivo experiments showed that Au/Gd nanodots had good biocompatibility and biosafety. Therefore, the prepared multifunctional nanoprobe may provide new strategies and insights for precise diagnosis of metastatic prostate cancer in clinical practice.


Assuntos
Neoplasias da Próstata , Tomografia Computadorizada por Raios X , Masculino , Humanos , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem
20.
Biosens Bioelectron ; 235: 115386, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37187060

RESUMO

Diabetic wounds are chronically hard-healing wounds. Bacterial infection, persistent inflammation and impaired angiogenesis are key factors affecting diabetic wound healing. Herein, inspired by pomegranate, Au/Ag nanodots (Au/AgNDs) with fluorescent and photothermal properties were adopted as the pomegranate-like core, and the polyvinyl alcohol hydrogel as the pomegranate-like shell to obtain the multifunctional nanocomposite wound dressing for promoting diabetic wounds healing and real-time self-monitoring the dressing state. On the one hand, the antibacterial and photothermal therapy synergistic strategy based on the nanocomposite has an excellent treatment effect on diabetic wounds by highly antibacterial, anti-inflammation, accelerating collagen deposition and angiogenesis. On the other hand, the nanocomposite can be used as "smart messenger" to determine the appropriate time for dressing replacement. With the release of Au/AgNDs from the nanocomposite, the photothermal performance and antibacterial activity of the wound dressing were reduced, and the fluorescence intensity decreased. The change of fluorescence intensity can be visualized by the naked eye, which guides the appropriate time for dressing replacement, and avoids secondary wound damage caused by frequent and blind dressing replacement. This work provides an effective strategy for the treatment of diabetic wounds and intelligent self-monitoring of the state of dressings in clinical practice.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus , Nanocompostos , Bandagens , Cicatrização , Antibacterianos , Diabetes Mellitus/terapia
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