33 research outputs found
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Accurate in vivo tumor detection using plasmonic-enhanced shifted-excitation Raman difference spectroscopy (SERDS)
For the majority of cancer patients, surgery is the primary method of treatment. In these cases, accurately removing the entire tumor without harming surrounding tissue is critical; however, due to the lack of intraoperative imaging techniques, surgeons rely on visual and physical inspection to identify tumors. Surface-enhanced Raman scattering (SERS) is emerging as a non-invasive optical alternative for intraoperative tumor identification, with high accuracy and stability. However, Raman detection requires dark rooms to work, which is not consistent with surgical settings. Methods: Herein, we used SERS nanoprobes combined with shifted-excitation Raman difference spectroscopy (SERDS) detection, to accurately detect tumors in xenograft murine model. Results: We demonstrate for the first time the use of SERDS for in vivo tumor detection in a murine model under ambient light conditions. We compare traditional Raman detection with SERDS, showing that our method can improve sensitivity and accuracy for this task. Conclusion: Our results show that this method can be used to improve the accuracy and robustness of in vivo Raman/SERS biomedical application, aiding the process of clinical translation of these technologies. © The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/). See http://ivyspring.com/terms for full terms and conditions
Plasmonics-enhanced and optically modulated delivery of gold nanostars into brain tumor
Plasmonics-active gold nanostars exhibiting strong imaging contrast and efficient photothermal transduction were synthesized for a novel pulsed laser-modulated plasmonics-enhanced brain tumor microvascular permeabilization. We demonstrate a selective, optically modulated delivery of nanoprobes into the tumor parenchyma with minimal off-target distribution
Plasmonics-enhanced and optically modulated delivery of gold nanostars into brain tumor
Plasmonics-active gold nanostars exhibiting strong imaging contrast and efficient photothermal transduction were synthesized for a novel pulsed laser-modulated plasmonics-enhanced brain tumor microvascular permeabilization. We demonstrate a selective, optically modulated delivery of nanoprobes into the tumor parenchyma with minimal off-target distribution
Resting-State Quantitative Electroencephalography Reveals Increased Neurophysiologic Connectivity in Depression
Symptoms of Major Depressive Disorder (MDD) are hypothesized to arise from dysfunction in brain networks linking the limbic system and cortical regions. Alterations in brain functional cortical connectivity in resting-state networks have been detected with functional imaging techniques, but neurophysiologic connectivity measures have not been systematically examined. We used weighted network analysis to examine resting state functional connectivity as measured by quantitative electroencephalographic (qEEG) coherence in 121 unmedicated subjects with MDD and 37 healthy controls. Subjects with MDD had significantly higher overall coherence as compared to controls in the delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–12 Hz), and beta (12–20 Hz) frequency bands. The frontopolar region contained the greatest number of “hub nodes” (surface recording locations) with high connectivity. MDD subjects expressed higher theta and alpha coherence primarily in longer distance connections between frontopolar and temporal or parietooccipital regions, and higher beta coherence primarily in connections within and between electrodes overlying the dorsolateral prefrontal cortical (DLPFC) or temporal regions. Nearest centroid analysis indicated that MDD subjects were best characterized by six alpha band connections primarily involving the prefrontal region. The present findings indicate a loss of selectivity in resting functional connectivity in MDD. The overall greater coherence observed in depressed subjects establishes a new context for the interpretation of previous studies showing differences in frontal alpha power and synchrony between subjects with MDD and normal controls. These results can inform the development of qEEG state and trait biomarkers for MDD
Ceremonial plant consumption at Middle Bronze Age Büklükale, Kırıkkale Province, central Turkey
A shaft-like room at the Middle Bronze Age site of Büklükale in central Turkey preserved a rich archaeobotanical assemblage of charred and mineralised plant remains, dominated by fruits, spices and nuts mixed with probable bread and wood charcoals. The remains were recovered in association with numerous ceramic vessels, jewellery and exotic artefacts. We combine identification and analysis of the seeds and wood charcoals contained in this deposit with studies of Old Assyrian and Hittite textual records to investigate the circumstances of the assemblage’s formation and its significance for further understanding trade and plant consumption in Bronze Age Anatolia. We present the earliest archaeobotanical example in the region of rare and exotic plant species being consumed in the context of one or more social gatherings, including those possibly linked to ceremonial or ritual events. This offers new insights into the role of plants in the economic and social life of the southwest Asian Bronze Age, as well as the role of commensality and feasting in early states
Folate Receptor-Targeted Theranostic Nanoconstruct for Surface-Enhanced Raman Scattering Imaging and Photodynamic Therapy
We report the synthesis of a folate
receptor (FR)-targeted theranostic
nanocomposite for surface-enhanced Raman scattering (SERS) imaging
and photodynamic therapy (PDT). FR-specific SERS detection and PDT
are demonstrated in vitro using two FR-positive cancer cell lines
and one FR-negative cancer cell lines
TAT Peptide-Functionalized Gold Nanostars: Enhanced Intracellular Delivery and Efficient NIR Photothermal Therapy Using Ultralow Irradiance
Gold nanoparticles have great potential in plasmonic
photothermal
therapy (photothermolysis), but their intracellular delivery and photothermolysis
efficiency have yet to be optimized. We show that TAT-peptide-functionalized
gold nanostars (NS) enter cells significantly more than bare or PEGylated
NS. The cellular uptake mechanism involves actin-driven lipid raft-mediated
macropinocytosis, where particles primarily accumulate in macropinosomes
but may also leak out into the cytoplasm. After 4-h incubation of
TAT-NS on BT549 breast cancer cells, photothermolysis was accomplished
using 850 nm pulsed laser under 0.2 W/cm<sup>2</sup> irradiation,
below the maximal permissible exposure of skin. These results demonstrate
the enhanced intracellular delivery and efficient photothermolysis
of TAT-NS, promising agents in cancer therapy
Cell-Penetrating Peptide Enhanced Intracellular Raman Imaging and Photodynamic Therapy
We present the application of a theranostic
system combining Raman
imaging and the photodynamic therapy (PDT) effect. The theranostic
nanoplatform was created by loading the photosensitizer, protoporphyrin
IX, onto a Raman-labeled gold nanostar. A cell-penetrating peptide,
TAT, enhanced intracellular accumulation of the nanoparticles in order
to improve their delivery and efficacy. The plasmonic gold nanostar
platform was designed to increase the Raman signal via the surface-enhanced
resonance Raman scattering (SERRS) effect. Theranostic SERS imaging
and photodynamic therapy using this construct were demonstrated on
BT-549 breast cancer cells. The TAT peptide allowed for effective
Raman imaging and photosensitization with the nanoparticle construct
after a 1 h incubation period. In the absence of the TAT peptide,
nanoparticle accumulation in the cells was not sufficient to be observed
by Raman imaging or to produce any photosensitization effect after
this short incubation period. There was no cytotoxic effect observed
after nanoparticle incubation, prior to light activation of the photosensitizer.
This report shows the first application of combined SERS imaging and
photosensitization from a theranostic nanoparticle construct