Sample records for near-infrared light therapy

  1. Transcranial Red and Near Infrared Light Transmission in a Cadaveric Model

    PubMed Central

    Jagdeo, Jared R.; Adams, Lauren E.; Brody, Neil I.; Siegel, Daniel M.

    2012-01-01

    Background and Objective Low level light therapy has garnered significant interest within the past decade. The exact molecular mechanisms of how red and near infrared light result in physiologic modulation are not fully understood. Heme moieties and copper within cells are red and near infrared light photoreceptors that induce the mitochondrial respiratory chain component cytochrome C oxidase, resulting in a cascade linked to cytoprotection and cellular metabolism. The copper centers in cytochrome C oxidase have a broad absorption range that peaks around 830 nm. Several in vitro and in vivo animal and human models exist that have demonstrated the benefits of red light and near infrared light for various conditions. Clinical applications for low level light therapy are varied. One study in particular demonstrated improved durable functional outcomes status post-stroke in patients treated with near infrared low level light therapy compared to sham treatment [1]. Despite previous data suggesting the beneficial effect in treating multiple conditions, including stroke, with low level light therapy, limited data exists that measures transmission in a human model. Study Design/Materials and Methods To investigate this idea, we measured the transmission of near infrared light energy, using red light for purposes of comparison, through intact cadaver soft tissue, skull bones, and brain using a commercially available LED device at 830 nm and 633 nm. Results Our results demonstrate that near infrared measurably penetrates soft tissue, bone and brain parenchyma in the formalin preserved cadaveric model, in comparison to negligible red light transmission in the same conditions. Conclusion These findings indicate that near infrared light can penetrate formalin fixed soft tissue, bone and brain and implicate that benefits observed in clinical studies are potentially related to direct action of near infrared light on neural tissue. PMID:23077622

  2. Smart pH-responsive upconversion nanoparticles for enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

    PubMed

    Wang, Sheng; Zhang, Lei; Dong, Chunhong; Su, Lin; Wang, Hanjie; Chang, Jin

    2015-01-01

    A smart pH-responsive photodynamic therapy system based on upconversion nanoparticle loaded PEG coated polymeric lipid vesicles (RB-UPPLVs) was designed and prepared. These RB-UPPLVs which are promising agents for deep cancer photodynamic therapy applications can achieve enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

  3. Progress in the Field of Constructing Near-Infrared Light-Responsive Drug Delivery Platforms.

    PubMed

    Zhou, Fang; Wang, Hanjie; Chang, Jin

    2016-03-01

    Stimuli-responsive materials have taken replace of traditional drug carriers due to their ability to achieve controlled release of their encapsulated contents. A variety of sensitive materials, such as polymers that respond to pH, light, and magnetic fields, are widely used to construct drug carriers, and achieved good results. Specifically, near-infrared light (NIR) responsive materials are of particular interest in drug delivery, as NIR can penetrate body tissue and is minimally absorbed by the body's water and hemoglobin and is less harmful to healthy cells than UV or visible light. Thus, the near-infrared excitation drug delivery systems (NIRDDSs) have some essential advantages just like being efficient to kill tumor cells, accurate to achieve the tumor sites and less damage to human body. Also, in the process of building the carriers, we may achieve a combination of controlled release chemotherapy, photothermal therapy (PTT) or photodynamic therapy (PDT). In addition, besides utilizing as drug delivery platforms, some carriers can achieve multifunctional tumor diagnosis and treatment, such as magnetic resonance imaging, optical imaging, drug carriers and PTT. In this review, based on the mechanism of NIR, we highlight diverse near-infrared light-responsive drug delivery platforms and recent advances in the development of NIRDDSs for cancer therapy primarily.

  4. Spot fat reduction by red and near infrared LED phototherapy

    NASA Astrophysics Data System (ADS)

    Lim, Sungkyoo; Park, Eal-Whan

    2018-02-01

    Low level light therapy (LLLT) using light from red and near infrared LEDs or Lasers have been reported effective as noninvasive methods for reducing spot fat. A total of 55 subjects were randomly divided into test groups and control groups for abdominal fat reduction clinical trial using red and near infrared LED phototherapy devices. Red and near infrared light with irradiance of 10 mW/cm2 were irradiated over the abdominal area to the test group for 30 minutes followed by 30 minutes of aerobic exercise, 3 times a week for 4 weeks. Control group used sham devices for 30 minutes and followed by 30 minutes of aerobic exercise. It is expected that red and near infrared LED phototherapy combined with aerobic exercise would be effective and safe for abdominal fat reduction without any side effects.

  5. Near-infrared mediated tumor destruction by photothermal effect of PANI-Np in vivo

    NASA Astrophysics Data System (ADS)

    Ibarra, L. E.; Yslas, E. I.; Molina, M. A.; Rivarola, C. R.; Romanini, S.; Barbero, C. A.; Rivarola, V. A.; Bertuzzi, M. L.

    2013-06-01

    Photothermal therapy is a therapy in which photon energy is converted into heat to kill cancer. The purpose of this study is to evaluate the in vivo efficacy of photothermal therapy, toxicity and hepatic and renal function of polyaniline nanoparticles (PANI-Np) in a tumor-bearing mice model. The in vivo efficacy of nanoparticles, following NIR light exposure, was assessed by examining tumor growth over time compared to the untreated control. Signs of drug toxicity and the histopathology and morphology of tumor and tissues, after intratumoral injection treatment, were examined or monitored. Excellent photothermal therapy efficacy is achieved upon intratumoral injection of PANI-Np followed by near-infrared light exposure. These results suggest that PANI-Np could be considered as an effective photothermal agent and pave the way to future cancer therapeutics.

  6. Development of a real-time and quantitative thrombus sensor for an extracorporeal centrifugal blood pump by near-infrared light

    PubMed Central

    Sakota, Daisuke; Fujiwara, Tatsuki; Ohuchi, Katsuhiro; Kuwana, Katsuyuki; Yamazaki, Hiroyuki; Kosaka, Ryo; Nishida, Masahiro; Mizuno, Tomohiro; Arai, Hirokuni; Maruyama, Osamu

    2017-01-01

    We developed an optical thrombus sensor for a monopivot extracorporeal centrifugal blood pump. In this study, we investigated its quantitative performance for thrombus detection in acute animal experiments of left ventricular assist using the pump on pathogen-free pigs. Optical fibers were set in the driver unit of the pump. The incident light at the near-infrared wavelength of 810 nm was aimed at the pivot bearing, and the resulting scattered light was guided to the optical fibers. The detected signal was analyzed to obtain the thrombus formation level. As a result, real-time and quantitative monitoring of the thrombus surface area on the pivot bearing was achieved with an accuracy of 3.6 ± 2.3 mm2. In addition, the sensing method using the near-infrared light was not influenced by changes in the oxygen saturation and the hematocrit. It is expected that the developed sensor will be useful for optimal anticoagulation management for long-term extracorporeal circulation therapies. PMID:29359096

  7. Development of a real-time and quantitative thrombus sensor for an extracorporeal centrifugal blood pump by near-infrared light.

    PubMed

    Sakota, Daisuke; Fujiwara, Tatsuki; Ohuchi, Katsuhiro; Kuwana, Katsuyuki; Yamazaki, Hiroyuki; Kosaka, Ryo; Nishida, Masahiro; Mizuno, Tomohiro; Arai, Hirokuni; Maruyama, Osamu

    2018-01-01

    We developed an optical thrombus sensor for a monopivot extracorporeal centrifugal blood pump. In this study, we investigated its quantitative performance for thrombus detection in acute animal experiments of left ventricular assist using the pump on pathogen-free pigs. Optical fibers were set in the driver unit of the pump. The incident light at the near-infrared wavelength of 810 nm was aimed at the pivot bearing, and the resulting scattered light was guided to the optical fibers. The detected signal was analyzed to obtain the thrombus formation level. As a result, real-time and quantitative monitoring of the thrombus surface area on the pivot bearing was achieved with an accuracy of 3.6 ± 2.3 mm 2 . In addition, the sensing method using the near-infrared light was not influenced by changes in the oxygen saturation and the hematocrit. It is expected that the developed sensor will be useful for optimal anticoagulation management for long-term extracorporeal circulation therapies.

  8. Near-Infrared-Light-Responsive Magnetic DNA Microgels for Photon- and Magneto-Manipulated Cancer Therapy.

    PubMed

    Wang, Yitong; Wang, Ling; Yan, Miaomiao; Dong, Shuli; Hao, Jingcheng

    2017-08-30

    Functional DNA molecules have been introduced into polymer-based nanocarrier systems to incorporate chemotherapy drugs for cancer therapy. Here is the first report of dual-responsive microgels composed of a core of Au nanorods and a shell of magnetic ionic liquid and DNA moieties in the cross-linking network simultaneously, as effective drug delivery vectors. TEM images indicated a magnetic polymer shell has an analogous "doughnut" shape which loosely surround the AuNRs core. When irradiated with a near-infrared-light (near-IR) laser, Au nanorods are the motors which convert the light to heat, leading to the release of the encapsulated payloads with high controllability. DNA acts not only as a cross-linker agent, but also as a gatekeeper to regulate the release of drugs. The internalization study and MTT assay confirm that these core-shell DNA microgels are excellent candidates which can enhance the cytotoxicity of cancer cells controlled by near-IR laser and shield the high toxicity of chemotherapeutic agents to improve the killing efficacy of chemotherapeutic agents efficiently in due course.

  9. Plasmonic photothermal heating of intraperitoneal tumors through the use of an implanted near-infrared source.

    PubMed

    Bagley, Alexander F; Hill, Samuel; Rogers, Gary S; Bhatia, Sangeeta N

    2013-09-24

    Plasmonic nanomaterials including gold nanorods are effective agents for inducing heating in tumors. Because near-infrared (NIR) light has traditionally been delivered using extracorporeal sources, most applications of plasmonic photothermal therapy have focused on isolated subcutaneous tumors. For more complex models of disease such as advanced ovarian cancer, one of the primary barriers to gold nanorod-based strategies is the adequate delivery of NIR light to tumors located at varying depths within the body. To address this limitation, a series of implanted NIR illumination sources are described for the specific heating of gold nanorod-containing tissues. Through computational modeling and ex vivo studies, a candidate device is identified and validated in a model of orthotopic ovarian cancer. As the therapeutic, imaging, and diagnostic applications of plasmonic nanomaterials progress, effective methods for NIR light delivery to challenging anatomical regions will complement ongoing efforts to advance plasmonic photothermal therapy toward clinical use.

  10. Near-infrared light-responsive nanomaterials in cancer therapeutics.

    PubMed

    Shanmugam, Vijayakumar; Selvakumar, S; Yeh, Chen-Sheng

    2014-09-07

    Noninvasive techniques, such as breath tests (urea breath test), blood pressure measurements using a sphygmomanometer and electrocardiography, were employed by a physician to perform classical diagnosis. The use of state-of-the-art noninvasive therapies at the organ level in modern medicine has gradually become possible. However, cancer treatment demands spatially and temporally controlled noninvasive therapy at the cell level because nonspecific toxicity often causes complicated side effects. To increase survival in cancer patients further, combination therapy and combination drugs are explored which demand high specificity to avoid combined-drug side effects. We believe that high specificity could be obtained by implementing near-infrared (NIR) light-assisted nanoparticles in photothermal therapy, chemotherapy, and photodynamic therapy. To refine this therapy and subsequently achieve high efficiency, novel nanomaterials have been designed and modified either to enhance the uptake and drug delivery to the cancer site, or control treatment to administer therapy efficiently. These modifications and developments have been demonstrated to achieve spatial and temporal control when conducting an in vivo xenograft, because the NIR light penetrated effectively the biological tissue. The nanoplatforms discussed in this review are grouped under the following subheadings: Au nanorods (NRs), Au nanoshells, other Au-related nanomaterials, graphene oxide, upconversion nanoparticles, and other related materials (including materials such as CuS, Fe3O4-related systems, and carbon nanotubes (CNTs)).

  11. Near-infrared deep brain stimulation via upconversion nanoparticle–mediated optogenetics

    NASA Astrophysics Data System (ADS)

    Chen, Shuo; Weitemier, Adam Z.; Zeng, Xiao; He, Linmeng; Wang, Xiyu; Tao, Yanqiu; Huang, Arthur J. Y.; Hashimotodani, Yuki; Kano, Masanobu; Iwasaki, Hirohide; Parajuli, Laxmi Kumar; Okabe, Shigeo; Teh, Daniel B. Loong; All, Angelo H.; Tsutsui-Kimura, Iku; Tanaka, Kenji F.; Liu, Xiaogang; McHugh, Thomas J.

    2018-02-01

    Optogenetics has revolutionized the experimental interrogation of neural circuits and holds promise for the treatment of neurological disorders. It is limited, however, because visible light cannot penetrate deep inside brain tissue. Upconversion nanoparticles (UCNPs) absorb tissue-penetrating near-infrared (NIR) light and emit wavelength-specific visible light. Here, we demonstrate that molecularly tailored UCNPs can serve as optogenetic actuators of transcranial NIR light to stimulate deep brain neurons. Transcranial NIR UCNP-mediated optogenetics evoked dopamine release from genetically tagged neurons in the ventral tegmental area, induced brain oscillations through activation of inhibitory neurons in the medial septum, silenced seizure by inhibition of hippocampal excitatory cells, and triggered memory recall. UCNP technology will enable less-invasive optical neuronal activity manipulation with the potential for remote therapy.

  12. Near-infrared roll-off-free electroluminescence from highly stable diketopyrrolopyrrole light emitting diodes

    PubMed Central

    Sassi, Mauro; Buccheri, Nunzio; Rooney, Myles; Botta, Chiara; Bruni, Francesco; Giovanella, Umberto; Brovelli, Sergio; Beverina, Luca

    2016-01-01

    Organic light emitting diodes (OLEDs) operating in the near-infrared spectral region are gaining growing relevance for emerging photonic technologies, such as lab-on-chip platforms for medical diagnostics, flexible self-medicated pads for photodynamic therapy, night vision and plastic-based telecommunications. The achievement of efficient near-infrared electroluminescence from solution-processed OLEDs is, however, an open challenge due to the low photoluminescence efficiency of most narrow-energy-gap organic emitters. Diketopyrrolopyrrole-boron complexes are promising candidates to overcome this limitation as they feature extremely high photoluminescence quantum yield in the near-infrared region and high chemical stability. Here, by incorporating suitably functionalized diketopyrrolopyrrole derivatives emitting at ~760 nm in an active matrix of poly(9,9-dioctylfluorene-alt-benzothiadiazole) and without using complex light out-coupling or encapsulation strategies, we obtain all-solution-processed NIR-OLEDs with external quantum efficiency as high as 0.5%. Importantly, our test-bed devices show no efficiency roll-off even for high current densities and high operational stability, retaining over 50% of the initial radiant emittance for over 50 hours of continuous operation at 10 mA/cm2, which emphasizes the great applicative potential of the proposed strategy. PMID:27677240

  13. Near Infrared Fluorescence Imaging in Nano-Therapeutics and Photo-Thermal Evaluation

    PubMed Central

    Vats, Mukti; Mishra, Sumit Kumar; Baghini, Mahdieh Shojaei; Chauhan, Deepak S.; Srivastava, Rohit; De, Abhijit

    2017-01-01

    The unresolved and paramount challenge in bio-imaging and targeted therapy is to clearly define and demarcate the physical margins of tumor tissue. The ability to outline the healthy vital tissues to be carefully navigated with transection while an intraoperative surgery procedure is performed sets up a necessary and under-researched goal. To achieve the aforementioned objectives, there is a need to optimize design considerations in order to not only obtain an effective imaging agent but to also achieve attributes like favorable water solubility, biocompatibility, high molecular brightness, and a tissue specific targeting approach. The emergence of near infra-red fluorescence (NIRF) light for tissue scale imaging owes to the provision of highly specific images of the target organ. The special characteristics of near infra-red window such as minimal auto-fluorescence, low light scattering, and absorption of biomolecules in tissue converge to form an attractive modality for cancer imaging. Imparting molecular fluorescence as an exogenous contrast agent is the most beneficial attribute of NIRF light as a clinical imaging technology. Additionally, many such agents also display therapeutic potentials as photo-thermal agents, thus meeting the dual purpose of imaging and therapy. Here, we primarily discuss molecular imaging and therapeutic potentials of two such classes of materials, i.e., inorganic NIR dyes and metallic gold nanoparticle based materials. PMID:28452928

  14. In vivo multimodality imaging and cancer therapy by near-infrared light-triggered trans-platinum pro-drug-conjugated upconverison nanoparticles.

    PubMed

    Dai, Yunlu; Xiao, Haihua; Liu, Jianhua; Yuan, Qinghai; Ma, Ping'an; Yang, Dongmei; Li, Chunxia; Cheng, Ziyong; Hou, Zhiyao; Yang, Piaoping; Lin, Jun

    2013-12-18

    Controlling anticancer drug activity and release on demand is very significant in cancer therapy. The photoactivated platinum(IV) pro-drug is stable in the dark and can be activated by UV light. In this study, we develop a multifunctional drug delivery system combining upconversion luminescence/magnetic resonance/computer tomography trimodality imaging and NIR-activated platinum pro-drug delivery. We use the core-shell structured upconversion nanoparticles to convert the absorbed NIR light into UV to activate the trans-platinum(IV) pro-drug, trans,trans,trans-[Pt(N3)2(NH3)(py)(O2CCH2CH2COOH)2]. Compared with using the UV directly, the NIR has a higher tissue penetration depth and is less harmful to health. Meanwhile, the upconversion nanoparticles can effectively deliver the platinum(IV) pro-drugs into the cells by endocytosis. The mice treated with pro-drug-conjugated nanoparticles under near-infrared (NIR) irradiation demonstrated better inhibition of tumor growth than that under direct UV irradiation. This multifunctional nanocomposite could be used as multimodality bioimaging contrast agents and transducers by converting NIR light into UV for control of drug activity in practical cancer therapy.

  15. Ultralow-Power Near Infrared Lamp Light Operable Targeted Organic Nanoparticle Photodynamic Therapy.

    PubMed

    Huang, Ling; Li, Zhanjun; Zhao, Yang; Zhang, Yuanwei; Wu, Shuang; Zhao, Jianzhang; Han, Gang

    2016-11-09

    Tissue penetration depth is a major challenge in practical photodynamic therapy (PDT). A biocompatible and highly effective near infrared (NIR)-light-absorbing carbazole-substituted BODIPY (Car-BDP) molecule is reported as a class of imaging-guidable deep-tissue activatable photosensitizers for PDT. Car-BDP possesses an intense, broad NIR absorption band (600-800 nm) with a remarkably high singlet oxygen quantum yield (Φ Δ = 67%). After being encapsulated with biodegradable PLA-PEG-FA polymers, Car-BDP can form uniform and small organic nanoparticles that are water-soluble and tumor-targetable. Rather than using laser light, such nanoparticles offer an unprecedented deep-tissue, tumor targeting photodynamic therapeutic effect by using an exceptionally low-power-density and cost-effective lamp light (12 mW cm -2 ). In addition, these nanoparticles can be simultaneously traced in vivo due to their excellent NIR fluorescence. This study signals a major step forward in photodynamic therapy by developing a new class of NIR-absorbing biocompatible organic nanoparticles for effective targeting and treatment of deep-tissue tumors. This work also provides a potential new platform for precise tumor-targeting theranostics and novel opportunities for future affordable clinical cancer treatment.

  16. Construction of near-infrared light-triggered reactive oxygen species-sensitive (UCN/SiO2-RB + DOX)@PPADT nanoparticles for simultaneous chemotherapy and photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Zhou, Fang; Zheng, Bin; Zhang, Ying; Wu, Yudong; Wang, Hanjie; Chang, Jin

    2016-06-01

    Combined therapy now plays a major role in cancer therapy due to the outcome of huge amounts of scientific experiments in recent years. However, all systems designed previously have been unable to simultaneously deliver therapy effects using several methods to produce a greater overall therapeutic effect. To solve the problem, we constructed a delivery system of near-infrared light (NIR)-triggered reactive oxygen species (ROS)-sensitive nanoparticles (NPs) for simultaneous chemotherapy and photodynamic therapy (PDT). The inner NP was assembled from a hydrophobic upconverting nanoparticle (UCN) core, with a thin silica shell linked with rose bengal (RB). Finally, a type of ROS-induced biodegradable polymer named poly-(1, 4-phenyleneacetone dimethylenethioketal) (PPADT) was self-assembled to form the NP as an outer shell to load the inner NP and doxorubicin (DOX). As the results show, the UCN core works as a transducer to convert deeply penetrating NIR to visible light for activating the photosensitizer RB for PDT under NIR excitation. In the meantime, the redundant ROS caused PPADT to biodegrade to release the loaded DOX, realizing simultaneous chemotherapy and PDT. Properties such as structure, size distribution, morphology, Fourier transform infrared spectroscopy, ROS production test, cell uptake test and combined therapy treatment effect in vitro were evaluated to prove NIR triggered ROS-sensitive (UCN/SiO2-RB + DOX)@PPADT NPs. Based on our data, this delivery system could provide an effective means to realize simultaneous chemotherapy and PDT through external NIR-triggered ROS sensitivity.

  17. Near-infrared light excited upconverting persistent nanophosphors in vivo for imaging-guided cell therapy.

    PubMed

    Zheng, Bin; Bai, Yang; Chen, Hongbin; Pan, Huizhuo; Ji, Wanying; Gong, Xiaoqun; Wu, Xiaoli; Wang, Hanjie; Chang, Jin

    2018-05-14

    Optical imaging for biological applications is in need of more sensitive tool. Persistent luminescent nanophosphors enable highly sensitive in vivo optical detection and almost completely avoids tissue autofluorescence. Nevertheless, the actual persistent luminescent nanophosphors necessitates ex vivo activation before systemic operation, which severely restricted the use of long-term imaging in vivo. Hence, we introduced a novel generation of optical nanophosphors, based on (Zn2SiO4: Mn): Y3+, Yb3+, Tm3+ upconverting persistent luminescent nanophosphors, these nanophosphors can be excited in vivo through living tissues by highly penetrating near-infrared light. We can trace labeled tumor therapeutic macrophages in vivo after endocytosing these nanophosphors in vitro and follow macrophages biodistribution by a simple whole animal optical detection. These nanophosphors will open novel potentials for cell therapy research and for a variety of diagnosis applications in vivo.

  18. Effect of NIR photobiomodulation therapy in a cellular wound healing model.

    PubMed

    König, Anke; Missalla, Svenja; Valesky, Eva M; Bernd, August; Kaufmann, Roland; Kippenberger, Stefan; Zöller, Nadja N

    2018-04-26

    Wound healing is a complex process which can be divided into four phases: hemostasis, inflammation, proliferation and scar-remodelling (1). Imbalance of cell proliferation, synthesis and degradation of extracellular matrix proteins can cause e.g. chronic wounds or the development of hypertrophic scars. In recent years the application of photobiomodulatory therapies has increased. Both low level light therapy (LLLT) and near infrared (NIR) have a high tissue penetration efficiency without inducing a severe surface temperature increase or pain (2). Water-filtered near-infrared irradiation (wIRA), composed of a thermal component and NIR (780nm-1.400nm), is applied for a variety of different clinical conditions including wound healing (3). This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Effects of linear-polarized near-infrared light irradiation on chronic pain.

    PubMed

    Huang, Dong; Gu, Yong-Hong; Liao, Qin; Yan, Xue-Bin; Zhu, Shai-Hong; Gao, Chang-Qing

    2012-01-01

    In order to study the efficacy of linear-polarized near-infrared light irradiation (LPNIR) on relieving chronic pain in conjunction with nerve block (NB) or local block (LB), a 3-week prospective, randomized, double-blind, controlled study was conducted to evaluate the pre- and post-therapy pain intensity. Visual analogue scales (VASs) were measured in all patients before and 6 months after therapy visiting the pain clinic during the period of August 2007 to January 2008. A total of 52 patients with either shoulder periarthritis or myofascial pain syndrome or lateral epicondylitis were randomly assigned into two groups by drawing lots. Patients in Group I were treated with NB or LB plus LPNIR; Group II patients, for their part, were treated with the same procedures as in Group I, but not using LPNIR. In both groups, the pain intensity (VAS score) decreased significantly immediately after therapy as compared to therapy. There was a significant difference between the test and control groups immediately after therapy (P < 0.05), while no effect 6 months later. No side effects were observed. It is concluded that LPNIR is an effective and safe modality to treat various chronic pains, which has synergic effects with NB or LB.

  20. Effects of Linear-Polarized Near-Infrared Light Irradiation on Chronic Pain

    PubMed Central

    Huang, Dong; Gu, Yong-Hong; Liao, Qin; Yan, Xue-Bin; Zhu, Shai-Hong; Gao, Chang-Qing

    2012-01-01

    In order to study the efficacy of linear-polarized near-infrared light irradiation (LPNIR) on relieving chronic pain in conjunction with nerve block (NB) or local block (LB), a 3-week prospective, randomized, double-blind, controlled study was conducted to evaluate the pre- and post-therapy pain intensity. Visual analogue scales (VASs) were measured in all patients before and 6 months after therapy visiting the pain clinic during the period of August 2007 to January 2008. A total of 52 patients with either shoulder periarthritis or myofascial pain syndrome or lateral epicondylitis were randomly assigned into two groups by drawing lots. Patients in Group I were treated with NB or LB plus LPNIR; Group II patients, for their part, were treated with the same procedures as in Group I, but not using LPNIR. In both groups, the pain intensity (VAS score) decreased significantly immediately after therapy as compared to therapy. There was a significant difference between the test and control groups immediately after therapy (P < 0.05), while no effect 6 months later. No side effects were observed. It is concluded that LPNIR is an effective and safe modality to treat various chronic pains, which has synergic effects with NB or LB. PMID:22593697

  1. Fabrication of Photothermal Stable Gold Nanosphere/Mesoporous Silica Hybrid Nanoparticle Responsive to Near-Infrared Light.

    PubMed

    Cheng, Bei; Xu, Peisheng

    2017-01-01

    Various gold nanoparticles have been explored in biomedical systems and proven to be promising in photothermal therapy and drug delivery. Among them, nanoshells were regarded as traditionally strong near infrared absorbers that have been widely used to generate photothermal effect for cancer therapy. However, the nanoshell is not photo-thermal stable and thus is not suitable for repeated irradiation. Here, we describe a novel discrete gold nanostructure by mimicking the continuous gold nanoshell-gold/mesoporous silica hybrid nanoparticle (GoMe). It possesses the best characteristics of both conventional gold nanoparticles and mesoporous silica nanoparticles, such as excellent photothermal converting ability as well as high drug loading capacity and triggerable drug release.

  2. [Theragnostic approaches using gold nanorods and near infrared light].

    PubMed

    Niidome, Takuro; Shiotani, Atsushi; Akiyama, Yasuyuki; Ohga, Akira; Nose, Keisuke; Pissuwan, Dakrong; Niidome, Yasuro

    2010-12-01

    Gold nanoparticles have unique optical properties such as surface-plasmon and photothermal effects. Such properties have resulted in gold nanoparticles having several clinical applications. Gold nanorods (which are rod-shaped gold nanoparticles) show a surface plasmon band in the near-infrared region. They have therefore been proposed as contrast agents for bioimaging, or as heating devices for photothermal therapy. Polyethylene glycol-modified gold nanorods systemically administrated into mice can be detected with integrating sphere, and the stability of the gold nanorods in blood flow evaluated. After intravenous injection of gold nanorods followed by near-infrared laser irradiation, significant tumor damage triggered by the photothermal effect was observed. To deliver gold nanorods to the target tissue, thermosensitive polymer gel-coated gold nanorods were prepared. After intravenous injection of the gel-modified gold nanorods and irradiation of the tumor, a larger amount of gold was detected in the irradiated tumor than in the non-irradiated tumor. This effect is due to the hydrophobic interaction between the cellular membrane or the extracellular matrix and the gel surfaces induced by the photothermal effect. Furthermore, the photothermal effect enhanced the permeability of the stratum corneum of the skin. As a result of treatment of the skin with ovalbumin and gold nanorods followed by near-infrared light irradiation, a significant amount of protein was detected in the skin. The gold nanorods therefore showed several functions as a photothermal nanodevice for bioimaging, thermal therapy, and a drug delivery system.

  3. Intense pulsed light, near infrared pulsed light, and fractional laser combination therapy for skin rejuvenation in Asian subjects: a prospective multi-center study in China.

    PubMed

    Tao, Li; Wu, Jiaqiang; Qian, Hui; Lu, Zhong; Li, Yuanhong; Wang, Weizhen; Zhao, Xiaozhong; Tu, Ping; Yin, Rui; Xiang, Leihong

    2015-09-01

    Ablative skin rejuvenation therapies have limitations for Asian people, including post-inflammatory hyperpigmentation and long down time. Non-ablative lasers are safer but have limited efficacy. This study is to investigate the safety and efficacy of a combination therapy consisting of intense pulsed light (IPL), near infrared (NIR) light, and fractional erbium YAG (Er:YAG) laser for skin rejuvenation in Asian people. This study recruited 113 subjects from six sites in China. Subjects were randomly assigned to a full-face group, who received combination therapy, and split-face groups, in which one half of the face received combination therapy and the other half received IPL monotherapy. Each subject received five treatment sessions during a period of 90 days. Subjects were followed up at 1 and 3 months post last treatment. Three months after last treatment, the full-face group (n = 57) had a global improvement rate of 29 % and 29 % for wrinkles, 32 % for skin texture, 33 % for pigment spots, 28 % for pore size, respectively. For patients in the split-face groups (n = 54), monotherapy side had a global improvement rate of 23 % and 20 % for wrinkles, 27 % for skin texture, 25 % for pigment spots, 25 % for pore size, respectively. Both combination therapy and monotherapy resulted in significant improvements at the follow-up visits compared to baseline (P < 0.001). Combination therapy showed significantly greater improvements compared to monotherapy at two follow-up visits (P < 0.05). Combination therapy is a safe and more effective strategy than IPL monotherapy for skin rejuvenation in Asian people.

  4. A thermo-degradable hydrogel with light-tunable degradation and drug release.

    PubMed

    Hu, Jingjing; Chen, Yihua; Li, Yunqi; Zhou, Zhengjie; Cheng, Yiyun

    2017-01-01

    The development of thermo-degradable hydrogels is of great importance in drug delivery. However, it still remains a huge challenge to prepare thermo-degradable hydrogels with inherent degradation, reproducible, repeated and tunable dosing. Here, we reported a thermo-degradable hydrogel that is rapidly degraded above 44 °C by a facile chemistry. Besides thermo-degradability, the hydrogel also undergoes rapid photolysis with ultraviolet light. By embedding photothermal nanoparticles or upconversion nanoparticles into the gel, it can release the entrapped cargoes such as dyes, enzymes and anticancer drugs in an on-demand and dose-tunable fashion upon near-infrared light exposure. The smart hydrogel works well both in vitro and in vivo without involving sophisticated syntheses, and is well suited for clinical cancer therapy due to the high transparency and non-invasiveness features of near-infrared light. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. The potential of transcranial photobiomodulation therapy for treatment of major depressive disorder.

    PubMed

    Salehpour, Farzad; Rasta, Seyed Hossein

    2017-05-24

    Major depressive disorder is a common debilitating mood disorder that affects quality of life. Prefrontal cortex abnormalities, an imbalance in neurotransmitters, neuroinflammation, and mitochondrial dysfunction are the major factors in the etiology of major depressive disorder. Despite the efficacy of pharmacotherapy in the treatment of major depressive disorder, 30%-40% of patients do not respond to antidepressants. Given this, exploring the alternative therapies for treatment or prevention of major depressive disorder has aroused interest among scientists. Transcranial photobiomodulation therapy is the use of low-power lasers and light-emitting diodes in the far-red to near-infrared optical region for stimulation of neuronal activities. This non-invasive modality improves the metabolic capacity of neurons due to more oxygen consumption and ATP production. Beneficial effects of transcranial photobiomodulation therapy in the wide range of neurological and psychological disorders have been already shown. In this review, we focus on some issue relating to the application of photobiomodulation therapy for major depressive disorder. There is some evidence that transcranial photobiomodulation therapy using near-infrared light on 10-Hz pulsed mode appears to be a hopeful technique for treatment of major depressive disorder. However, further studies are necessary to find the safety of this method and to determine its effective treatment protocol.

  6. Novel concept of the smart NIR-light-controlled drug release of black phosphorus nanostructure for cancer therapy.

    PubMed

    Qiu, Meng; Wang, Dou; Liang, Weiyuan; Liu, Liping; Zhang, Yin; Chen, Xing; Sang, David Kipkemoi; Xing, Chenyang; Li, Zhongjun; Dong, Biqin; Xing, Feng; Fan, Dianyuan; Bao, Shiyun; Zhang, Han; Cao, Yihai

    2018-01-16

    A biodegradable drug delivery system (DDS) is one the most promising therapeutic strategies for cancer therapy. Here, we propose a unique concept of light activation of black phosphorus (BP) at hydrogel nanostructures for cancer therapy. A photosensitizer converts light into heat that softens and melts drug-loaded hydrogel-based nanostructures. Drug release rates can be accurately controlled by light intensity, exposure duration, BP concentration, and hydrogel composition. Owing to sufficiently deep penetration of near-infrared (NIR) light through tissues, our BP-based system shows high therapeutic efficacy for treatment of s.c. cancers. Importantly, our drug delivery system is completely harmless and degradable in vivo. Together, our work proposes a unique concept for precision cancer therapy by external light excitation to release cancer drugs. If these findings are successfully translated into the clinic, millions of patients with cancer will benefit from our work.

  7. The Use of NASA Light-Emitting Diode Near-Infrared Technology for Biostimulation

    NASA Technical Reports Server (NTRS)

    Whelan, Harry T.

    2002-01-01

    Studies on cells exposed to microgravity and hypergravity indicate that human cells need gravity to stimulate growth. As the gravitational force increases or decreases, the cell function responds in a linear fashion. This poses significant health risks for astronauts in long-term spaceflight. The application of light therapy with the use of NASA LEDs will significantly improve the medical care that is available to astronauts on long-term space missions. NASA LEDs stimulate the basic energy processes in the mitochondria (energy compartments) of each cell, particularly when near-infrared light is used to activate the color sensitive chemicals (chromophores, cytochrome systems) inside. Optimal LED wavelengths include 680, 730 and 880 nm and our laboratory has improved the healing of wounds in laboratory animals by using both NASA LED light and hyperbaric oxygen. Furthermore, DNA synthesis in fibroblasts and muscle cells has been quintupled using NASA LED light alone, in a single application combining 680, 730 and 880 nm each at 4 Joules per centimeter squared. Muscle and bone atrophy are well documented in astronauts, and various minor injuries occurring in space have been reported not to heal until landing on Earth. An LED blanket device may be used for the prevention of bone and muscle atrophy in astronauts. The depth of near-infrared light penetration into human tissue has been measured spectroscopically.

  8. Measurement of light penetration of near-infrared laser at the lumbosacral nerves in rats

    NASA Astrophysics Data System (ADS)

    Ishibashi, Naoya; Shimoyama, Hiroshi; Kawase, Yuki; Motohara, Shosaku; Okayama, Takamitsu; Niwa, Daisuke; Koyama, Jun

    2018-02-01

    Photobiomodulation or low level laser therapy (LLLT) has been utilized in various areas of medical practice including pain relief, wound healing, and inflammation treatment. Some recent animal studies have reported that near-infrared laser irradiation to the lumbosacral nerves transcutateously relieves neuropathic pain by controlling activity of lumbosacral nerves. However, transcutaneous laser penetration to the nerves has not yet been fully elucidated. Our aim is to determine the light penetration to lumbosacral nerves when near-infrared laser was irradiated transcutateously to lumbosacral nerves. We implanted photodiodes near the lumbosacral nerves of rats and connected the photodiodes to an oscilloscope through an amplifier. Near-infrared lasers (wavelengths: 808 nm and 830 nm) were irradiated through the skin at 2, 5 and 10 W pulses (Duty 10%, 5 Hz) and outputs of photodiodes were collected. After irradiation, the depth of the photodiodes and the nerves from the skin surface were determined by micro-CT device. The result showed that the fluence rate at the lumbosacral nerves was 179+/-19.2 mW/cm2 and 232+/-20.7 mW/cm2 when the 808-nm and 830-nm laser was irradiated at 10 W respectively. These findings would be beneficial for following study of photobiomodulation.

  9. A visible Chinese human-combined Monte Carlo simulation study on low-level light therapy of stroke

    NASA Astrophysics Data System (ADS)

    Wang, Pengbo; Pan, Boan; Zhong, Fulin; Li, Ting

    2017-02-01

    Stroke is a devastating disease, which is the third leading cause of death and disability worldwide. Although the incidence of stroke increases progressively with age, morbidity among young and middle-aged adults is increasing annually. Medications nevertheless remain the bulwarks of stroke. The treatment is ineffective, speculative and has a long treatment cycle. The function of acupuncture and moxibustion, which are potential therapeutic tools for stroke, is still controversial. Recently, Low-level light therapy (LLLT) has been demonstrated potent in vivo efficacy for treatment of ischemic conditions of acute myocardial infraction and stroke in multiple validated animal models. Optimum LLLT treatment has a dominant influence on therapy of stroke. While more than a thousand clinical trials have been halted, only a few trials on animals have been reported. We addressed this issue by simulating near-infrared light propagation with accurate visible Chinese human head by Monte Carlo modeling. The visible human head embody region of atherosclerotic plaques in head. Through comparing the light propagation of different light illumination, we can get a precise, optimized and straightforward treatment. Here, we developed a LLLT helmet for treating stroke depend on near-infrared light. There are more than 30 LED arrays in in multi-layered 3D printed helmet. Each LED array has independent water-cooling module and can be adjusted to touch the head of different subjects based on Electro pneumatic module. Moreover, the software provides the setup of illumination parameters and 3D distribution of light fluence rate distribution in human brain.

  10. Effect of low-level light therapy on diabetic foot ulcers: a near-infrared spectroscopy study

    NASA Astrophysics Data System (ADS)

    Salvi, Massimo; Rimini, Daniele; Molinari, Filippo; Bestente, Gianni; Bruno, Alberto

    2017-03-01

    Diabetic foot ulcer (DFU) is a diabetic complication due to peripheral vasculopathy and neuropathy. A promising technology for wound healing in DFU is low-level light therapy (LLLT). Despite several studies showing positive effects of LLLT on DFU, LLLT's physiological effects have not yet been studied. The objective of this study was to investigate vascular and nervous systems modification in DFU after LLLT. Two samples of 45 DFU patients and 11 healthy controls (HCs) were recruited. The total hemoglobin (totHb) concentration change was monitored before and after LLLT by near-infrared spectroscopy and analyzed in time and frequency domains. The spectral power of the totHb changes in the very-low frequency (VLF, 20 to 60 mHz) and low frequency (LF, 60 to 140 mHz) bandwidths was calculated. Data analysis revealed a mean increase of totHb concentration after LLLT in DFU patients, but not in HC. VLF/LF ratio decreased significantly after the LLLT period in DFU patients (indicating an increased activity of the autonomic nervous system), but not in HC. Eventually, different treatment intensities in LLLT therapy showed a different response in DFU. Overall, our results demonstrate that LLLT improves blood flow and autonomic nervous system regulation in DFU and the importance of light intensity in therapeutic protocols.

  11. Effect of low-level light therapy on diabetic foot ulcers: a near-infrared spectroscopy study.

    PubMed

    Salvi, Massimo; Rimini, Daniele; Molinari, Filippo; Bestente, Gianni; Bruno, Alberto

    2017-03-01

    Diabetic foot ulcer (DFU) is a diabetic complication due to peripheral vasculopathy and neuropathy. A promising technology for wound healing in DFU is low-level light therapy (LLLT). Despite several studies showing positive effects of LLLT on DFU, LLLT’s physiological effects have not yet been studied. The objective of this study was to investigate vascular and nervous systems modification in DFU after LLLT. Two samples of 45 DFU patients and 11 healthy controls (HCs) were recruited. The total hemoglobin (totHb) concentration change was monitored before and after LLLT by near-infrared spectroscopy and analyzed in time and frequency domains. The spectral power of the totHb changes in the very-low frequency (VLF, 20 to 60 mHz) and low frequency (LF, 60 to 140 mHz) bandwidths was calculated. Data analysis revealed a mean increase of totHb concentration after LLLT in DFU patients, but not in HC. VLF/LF ratio decreased significantly after the LLLT period in DFU patients (indicating an increased activity of the autonomic nervous system), but not in HC. Eventually, different treatment intensities in LLLT therapy showed a different response in DFU. Overall, our results demonstrate that LLLT improves blood flow and autonomic nervous system regulation in DFU and the importance of light intensity in therapeutic protocols.

  12. Optoacoustic theranostics

    NASA Astrophysics Data System (ADS)

    Petrov, Irene Y.; Micci, Maria-Adelaide; Prough, Donald S.; Petrov, Yuriy; Guptarak, Jutatip; Grant, Auston C.; Parsley, Margaret A.; Bolding, Ian J.; Esenaliev, Rinat O.

    2018-03-01

    Optoacoustic diagnostics is based on detection and analysis of optoacoustic waves induced in tissues. It may find a number of important clinical applications in large populations of patients such as diagnostics of cerebral hypoxia, circulatory shock, etc. Recently, we proposed Nano-Pulse Laser Therapy (NPLT) which utilizes short optical pulses (typically, shorter than hundreds of nanoseconds) to generate optoacoustic waves in tissues upon stress-confined irradiation. It is well known that continuous wave low-level near-infrared light can be used for therapy/photobiomodulation to stimulate, repair, regenerate, and protect injured tissue. In the past few years, new works emerged on therapeutic effects of low-intensity ultrasound waves. The NPLT consists of irradiating tissue by both lowlevel light and optoacoustic waves/ultrasound that combines merits of low-level light and ultrasound therapies. In this work we propose optoacoustic theranostics that can be used for diagnostics, optoacoustic therapy/NPLT, and monitoring of therapeutic response during and after therapy. We developed and built pulsed, tunable, near infrared (680-1064 nm), fiber-coupled systems for optoacoustic theranostics and tested them in rats with traumatic brain injury (TBI). Low energy pulses were used for optoacoustic monitoring of cerebral blood oxygenation, while higher energy pulses were used for the NPLT. Our studies show that TBI results in cerebral hypoxia, while a 5-minute transcranial application of NPLT significantly reduces negative effects of TBI as assessed by vestibulomotor, cognitive, and immunofluorescence tests. The obtained results suggest that the optoacoustic theranostics may be used for diagnostics and management of TBI and other disorders.

  13. Gold Nanorods as Nanodevices for Bioimaging, Photothermal Therapeutics, and Drug Delivery.

    PubMed

    Haine, Aung Thu; Niidome, Takuro

    2017-01-01

    Gold nanorods are promising metals in several biomedical applications such as bioimaging, thermal therapy, and drug delivery. Gold nanorods have strong absorption bands in near-infrared (NIR) light region and show photothermal effects. Since NIR light can penetrate deeply into tissues, their unique optical, chemical, and biological properties have attracted considerable clinical interest. Gold nanorods are expected to act not only as on-demand thermal converters for photothermal therapy but also as mediators of a controlled drug-release system responding to light irradiation. In this review, we discuss current progress using gold nanorods as bioimaging platform, phototherapeutic agents, and drug delivery vehicles.

  14. Near-infrared light-activated red-emitting upconverting nanoplatform for T1-weighted magnetic resonance imaging and photodynamic therapy.

    PubMed

    Tang, Xiang-Long; Wu, Jun; Lin, Ben-Lan; Cui, Sheng; Liu, Hong-Mei; Yu, Ru-Tong; Shen, Xiao-Dong; Wang, Ting-Wei; Xia, Wei

    2018-05-12

    Photodynamic therapy (PDT) has increasingly become an efficient and attractive cancer treatment modality based on reactive oxygen species (ROS) that can induce tumor death after irradiation with ultraviolet or visible light. Herein, to overcome the limited tissue penetration in traditional PDT, a novel near-infrared (NIR) light-activated NaScF 4 : 40% Yb, 2% Er@CaF 2 upconversion nanoparticle (rUCNP) is successfully designed and synthesized. Chlorin e6, a photosensitizer and a chelating agent for Mn 2+ , is loaded into human serum albumin (HSA) that further conjugates onto rUCNPs. To increase the ability to target glioma tumor, an acyclic Arg-Gly-Asp peptide (cRGDyK) is linked to rUCNPs@HSA(Ce6-Mn). This nanoplatform enables efficient adsorption and conversion of NIR light (980 nm) into bright red emission (660 nm), which can trigger the photosensitizer Ce6-Mn complex for PDT and T 1 -weighted magnetic resonance imaging (T 1 -weighted MRI) for glioma diagnosis. Our in vitro and in vivo experiments demonstrate that NIR light-activated and glioma tumor-targeted PDT can generate large amounts of intracellular ROS that induce U87 cell apoptosis and suppress glioma tumor growth owing to the deep tissue penetration of irradiated light and excellent tumor-targeting ability. Thus, this nanoplatform holds potential for applications in T 1 -weighted MRI diagnosis and PDT of glioma for antitumor therapy. A near-infrared (NIR) light-activated nanoplatform for photodynamic therapy (PDT) was designed and synthesized. The Red-to-Green (R/G) ratio of NaScF 4 : 40% Yb, 2% Er almost reached 9, a value that was much higher than that of a traditional Yb/Er-codoped upconversion nanoparticle (rUCNP). By depositing a CaF 2 shell, the red-emission intensities of the rUCNPs were seven times strong as that of NaScF 4 : 40% Yb, 2% Er. The enhanced red-emitting rUCNPs could be applied in many fields such as bioimaging, controlled release, and real-time diagnosis. The nanoplatform had a strong active glioma-targeting ability, and all results achieved on subcutaneous glioma demonstrated that our NIR light-activated red-emitting upconverting nanoplatform was efficient for PDT. By loading Ce6-Mn complex into rUCNPs@HSA-RGD, the nanoplatform could be used as a T 1 -weighted magnetic resonance imaging agent for tumor diagnosis. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Broadband near-field infrared spectroscopy with a high temperature plasma light source.

    PubMed

    Lahneman, D J; Huffman, T J; Xu, Peng; Wang, S L; Grogan, T; Qazilbash, M M

    2017-08-21

    Scattering-type scanning near-field optical microscopy (S-SNOM) has enormous potential as a spectroscopy tool in the infrared spectral range where it can probe phonon resonances and carrier dynamics at the nanometer lengths scales. However, its applicability is limited by the lack of practical and affordable table-top light sources emitting intense broadband infrared radiation in the 100 cm -1 to 2,500 cm -1 spectral range. This paper introduces a high temperature plasma light source that is both ultra-broadband and has much more radiant power in the infrared spectral range than conventional, table-top thermal light sources such as the globar. We implement this plasma lamp in our near-field optical spectroscopy set up and demonstrate its capability as a broadband infrared nano-spectroscopy light source by obtaining near-field infrared amplitude and phase spectra of the phonon resonances of SiO 2 and SrTiO 3 .

  16. Near infrared photoimmunotherapy in the treatment of disseminated peritoneal ovarian cancer

    PubMed Central

    Sato, Kazuhide; Hanaoka, Hirofumi; Watanabe, Rira; Nakajima, Takahito; Choyke, Peter L.; Kobayashi, Hisataka

    2014-01-01

    Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of intravenously injected antibodies for targeting tumors with the toxicity induced by photosensitizers after exposure to near infrared (NIR) light. Herein, we evaluate the efficacy of NIR-PIT in a mouse model of disseminated peritoneal ovarian cancer. In vitro and in vivo experiments were conducted with a HER2-expressing, luciferase expressing, ovarian cancer cell line (SKOV-luc). An antibody-photosensitizer conjugate (APC) consisting of trastuzumab and a phthalocyanine dye, IRDye-700DX, was synthesized (tra-IR700) and cells or tumors were exposed to near infrared (NIR) light. In vitro PIT cytotoxicity was assessed with dead staining and luciferase activity in freely growing cells and in a 3D spheroid model. In vivo NIR-PIT was performed in mice with tumors implanted in the peritoneum and in the flank and these assessed by tumor volume and/or bioluminescence. In vitro NIR-PIT-induced cytotoxicity was light dose dependent. Repeated light exposures induced complete tumor cell killing in the 3D spheroid model. In vivo the anti-tumor effects of NIR-PIT were confirmed by significant reductions in both tumor volume and luciferase activity in the flank model (NIR-PIT vs control in tumor volume changes at day 10; p=0.0001, NIR-PIT vs control in luciferase activity at day 4; p=0.0237), and the peritoneal model (NIR-PIT vs control in luciferase activity at day 7; p=0.0037). NIR-PIT provided effective cell killing in this HER2 positive model of disseminated peritoneal ovarian cancer. Thus, NIR-PIT is a promising new therapy for the treatment of disseminated peritoneal tumors. PMID:25416790

  17. Theranostic reduction-sensitive gemcitabine prodrug micelles for near-infrared imaging and pancreatic cancer therapy

    NASA Astrophysics Data System (ADS)

    Han, Haijie; Wang, Haibo; Chen, Yangjun; Li, Zuhong; Wang, Yin; Jin, Qiao; Ji, Jian

    2015-12-01

    A biodegradable and reduction-cleavable gemcitabine (GEM) polymeric prodrug with in vivo near-infrared (NIR) imaging ability was reported. This theranostic GEM prodrug PEG-b-[PLA-co-PMAC-graft-(IR820-co-GEM)] was synthesized by ring-opening polymerization and ``click'' reaction. The as-prepared reduction-sensitive prodrug could self-assemble into prodrug micelles in aqueous solution confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). In vitro drug release studies showed that these prodrug micelles were able to release GEM in an intracellular-mimicking reductive environment. These prodrug micelles could be effectively internalized by BxPC-3 pancreatic cancer cells, which were observed by confocal laser scanning microscopy (CLSM). Meanwhile, a methyl thiazolyl tetrazolium (MTT) assay demonstrated that this prodrug exhibited high cytotoxicity against BxPC-3 cells. The in vivo whole-animal near-infrared (NIR) imaging results showed that these prodrug micelles could be effectively accumulated in tumor tissue and had a longer blood circulation time than IR820-COOH. The endogenous reduction-sensitive gemcitabine prodrug micelles with the in vivo NIR imaging ability might have great potential in image-guided pancreatic cancer therapy.A biodegradable and reduction-cleavable gemcitabine (GEM) polymeric prodrug with in vivo near-infrared (NIR) imaging ability was reported. This theranostic GEM prodrug PEG-b-[PLA-co-PMAC-graft-(IR820-co-GEM)] was synthesized by ring-opening polymerization and ``click'' reaction. The as-prepared reduction-sensitive prodrug could self-assemble into prodrug micelles in aqueous solution confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). In vitro drug release studies showed that these prodrug micelles were able to release GEM in an intracellular-mimicking reductive environment. These prodrug micelles could be effectively internalized by BxPC-3 pancreatic cancer cells, which were observed by confocal laser scanning microscopy (CLSM). Meanwhile, a methyl thiazolyl tetrazolium (MTT) assay demonstrated that this prodrug exhibited high cytotoxicity against BxPC-3 cells. The in vivo whole-animal near-infrared (NIR) imaging results showed that these prodrug micelles could be effectively accumulated in tumor tissue and had a longer blood circulation time than IR820-COOH. The endogenous reduction-sensitive gemcitabine prodrug micelles with the in vivo NIR imaging ability might have great potential in image-guided pancreatic cancer therapy. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06734k

  18. Near-infrared spectroscopic tissue imaging for medical applications

    DOEpatents

    Demos,; Stavros, Staggs [Livermore, CA; Michael, C [Tracy, CA

    2006-03-21

    Near infrared imaging using elastic light scattering and tissue autofluorescence are explored for medical applications. The approach involves imaging using cross-polarized elastic light scattering and tissue autofluorescence in the Near Infra-Red (NIR) coupled with image processing and inter-image operations to differentiate human tissue components.

  19. Near-infrared spectroscopic tissue imaging for medical applications

    DOEpatents

    Demos, Stavros [Livermore, CA; Staggs, Michael C [Tracy, CA

    2006-12-12

    Near infrared imaging using elastic light scattering and tissue autofluorescence are explored for medical applications. The approach involves imaging using cross-polarized elastic light scattering and tissue autofluorescence in the Near Infra-Red (NIR) coupled with image processing and inter-image operations to differentiate human tissue components.

  20. Biological effects and medical applications of infrared radiation

    PubMed Central

    Tsai, Shang-Ru; Hamblin, Michael R

    2017-01-01

    Infrared (IR) radiation is electromagnetic radiation with wavelengths between 760 nm and 100,000 nm. Low-level light therapy (LLLT) or photobiomodulation (PBM) therapy generally employs light at red and near-infrared wavelengths (600–100 nm) to modulate biological activity. Many factors, conditions, and parameters influence the therapeutic effects of IR, including fluence, irradiance, treatment timing and repetition, pulsing, and wavelength. Increasing evidence suggests that IR can carry out photostimulation and photobiomodulation effects particularly benefiting neural stimulation, wound healing, and cancer treatment. Nerve cells respond particularly well to IR, which has been proposed for a range of neurostimulation and neuromodulation applications, and recent progress in neural stimulation and regeneration are discussed in this review. The applications of IR therapy have moved on rapidly in recent years. For example, IR therapy has been developed that does not actually require an external power source, such as IR-emitting materials, and garments that can be powered by body heat alone. Another area of interest is the possible involvement of solar IR radiation in photoaging or photorejuvenation as opposites sides of the coin, and whether sunscreens should protect against solar IR? A better understanding of new developments and biological implications of IR could help us to improve therapeutic effectiveness or develop new methods of PBM using IR wavelengths. PMID:28441605

  1. Biological effects and medical applications of infrared radiation.

    PubMed

    Tsai, Shang-Ru; Hamblin, Michael R

    2017-05-01

    Infrared (IR) radiation is electromagnetic radiation with wavelengths between 760nm and 100,000nm. Low-level light therapy (LLLT) or photobiomodulation (PBM) therapy generally employs light at red and near-infrared wavelengths (600-100nm) to modulate biological activity. Many factors, conditions, and parameters influence the therapeutic effects of IR, including fluence, irradiance, treatment timing and repetition, pulsing, and wavelength. Increasing evidence suggests that IR can carry out photostimulation and photobiomodulation effects particularly benefiting neural stimulation, wound healing, and cancer treatment. Nerve cells respond particularly well to IR, which has been proposed for a range of neurostimulation and neuromodulation applications, and recent progress in neural stimulation and regeneration are discussed in this review. The applications of IR therapy have moved on rapidly in recent years. For example, IR therapy has been developed that does not actually require an external power source, such as IR-emitting materials, and garments that can be powered by body heat alone. Another area of interest is the possible involvement of solar IR radiation in photoaging or photorejuvenation as opposites sides of the coin, and whether sunscreens should protect against solar IR? A better understanding of new developments and biological implications of IR could help us to improve therapeutic effectiveness or develop new methods of PBM using IR wavelengths. Copyright © 2016. Published by Elsevier B.V.

  2. Doxorubicin and Indocyanine Green Loaded Hybrid Bicelles for Fluorescence Imaging Guided Synergetic Chemo/Photothermal Therapy.

    PubMed

    Lin, Li; Liang, Xiaolong; Xu, Yunxue; Yang, Yongbo; Li, Xiaoda; Dai, Zhifei

    2017-09-20

    Hybrid bicelles have been demonstrated to have great potential for hydrophobic drug delivery. Herein, we report a near-infrared light-driven, temperature-sensitive hybrid bicelles co-encapsulating hydrophobic doxorubicin (DOX) and indocyanine green (ICG) (DOX/ICG@HBs). Encapsulation of ICG into the lipid bilayer membrane of DOX/ICG@HBs results in higher photostability than free ICG. DOX/ICG@HBs exhibited temperature-regulated drug release behavior and significant photothermal cytotoxicity. After tail vein injection, such discotic nanoparticles of DOX/ICG@HBs were found to accumulate selectively at the tumor site and act as an efficient probe to enhance fluorescence imaging greatly. The in vivo experiments showed that the DOX/ICG@HBs-mediated chemo- and photothermal combination therapy was more cytotoxic to tumor cells than the photothermal treatment or the chemotherapy alone due to the synergistic effect, reducing the occurrence of tumor metastasis. Therefore, DOX/ICG@HBs can act as a powerful nanotheranostic agent for chemo/photothermal therapy of cancer under the guidance of near-infrared fluorescence imaging.

  3. Near infrared and visible face recognition based on decision fusion of LBP and DCT features

    NASA Astrophysics Data System (ADS)

    Xie, Zhihua; Zhang, Shuai; Liu, Guodong; Xiong, Jinquan

    2018-03-01

    Visible face recognition systems, being vulnerable to illumination, expression, and pose, can not achieve robust performance in unconstrained situations. Meanwhile, near infrared face images, being light- independent, can avoid or limit the drawbacks of face recognition in visible light, but its main challenges are low resolution and signal noise ratio (SNR). Therefore, near infrared and visible fusion face recognition has become an important direction in the field of unconstrained face recognition research. In order to extract the discriminative complementary features between near infrared and visible images, in this paper, we proposed a novel near infrared and visible face fusion recognition algorithm based on DCT and LBP features. Firstly, the effective features in near-infrared face image are extracted by the low frequency part of DCT coefficients and the partition histograms of LBP operator. Secondly, the LBP features of visible-light face image are extracted to compensate for the lacking detail features of the near-infrared face image. Then, the LBP features of visible-light face image, the DCT and LBP features of near-infrared face image are sent to each classifier for labeling. Finally, decision level fusion strategy is used to obtain the final recognition result. The visible and near infrared face recognition is tested on HITSZ Lab2 visible and near infrared face database. The experiment results show that the proposed method extracts the complementary features of near-infrared and visible face images and improves the robustness of unconstrained face recognition. Especially for the circumstance of small training samples, the recognition rate of proposed method can reach 96.13%, which has improved significantly than 92.75 % of the method based on statistical feature fusion.

  4. Confocal retinal imaging using a digital light projector with a near infrared VCSEL source

    NASA Astrophysics Data System (ADS)

    Muller, Matthew S.; Elsner, Ann E.

    2018-02-01

    A custom near infrared VCSEL source has been implemented in a confocal non-mydriatic retinal camera, the Digital Light Ophthalmoscope (DLO). The use of near infrared light improves patient comfort, avoids pupil constriction, penetrates the deeper retina, and does not mask visual stimuli. The DLO performs confocal imaging by synchronizing a sequence of lines displayed with a digital micromirror device to the rolling shutter exposure of a 2D CMOS camera. Real-time software adjustments enable multiply scattered light imaging, which rapidly and cost-effectively emphasizes drusen and other scattering disruptions in the deeper retina. A separate 5.1" LCD display provides customizable visible stimuli for vision experiments with simultaneous near infrared imaging.

  5. Polymeric mixed micelles loaded mitoxantrone for overcoming multidrug resistance in breast cancer via photodynamic therapy

    PubMed Central

    Zhao, Yiqiao; Yu, Hua; Zhou, Haiyu; Chen, Meiwan

    2017-01-01

    Mitoxantrone (MIT) is an anticancer agent with photosensitive properties that is commonly used in various cancers. Multidrug resistance (MDR) effect has been an obstacle to using MIT for cancer therapy. Photochemical internalization, on account of photodynamic therapy, has been applied to improve the therapeutic effect of cancers with MDR effect. In this study, an MIT-poly(ε-caprolactone)-pluronic F68-poly(ε-caprolactone)/poly(d,l-lactide-co-glycolide)–poly(ethylene glycol)–poly(d,l-lactide-co-glycolide) (MIT-PFP/PPP) mixed micelles system was applied to reverse the effect of MDR in MCF-7/ADR cells via photochemical reaction when exposed to near-infrared light. MIT-PFP/PPP mixed micelles showed effective interaction with near-infrared light at the wavelength of 660 nm and exerted great cytotoxicity in MCF-7/ADR cells with irradiation. Furthermore, MIT-PFP/PPP mixed micelles could improve reactive oxygen species (ROS) levels, decrease P-glycoprotein activity, and increase the cellular uptake of drugs with improved intracellular drug concentrations, which induced cell apoptosis in MCF-7/ADR cells under irradiation, despite MDR effect, as indicated by the increased level of cleaved poly ADP-ribose polymerase. These findings suggested that MIT-PFP/PPP mixed micelles may become a promising strategy to effectively reverse the MDR effect via photodynamic therapy in breast cancer. PMID:28919756

  6. Polypeptide-Based Gold Nanoshells for Photothermal Therapy.

    PubMed

    Mayle, Kristine M; Dern, Kathryn R; Wong, Vincent K; Sung, Shijun; Ding, Ke; Rodriguez, April R; Taylor, Zachary; Zhou, Z Hong; Grundfest, Warren S; Deming, Timothy J; Kamei, Daniel T

    2017-02-01

    Targeted killing of cancer cells by engineered nanoparticles holds great promise for noninvasive photothermal therapy applications. We present the design and generation of a novel class of gold nanoshells with cores composed of self-assembled block copolypeptide vesicles with photothermal properties. Specifically, poly(L-lysine) 60 - block-poly(L-leucine) 20 (K 60 L 20 ) block copolypeptide vesicles coated with a thin layer of gold demonstrate enhanced absorption of light due to surface plasmon resonance (SPR) in the near-infrared range. We show that the polypeptide-based K 60 L 20 gold nanoshells have low toxicity in the absence of laser exposure, significant heat generation upon exposure to near-infrared light, and, as a result, localized cytotoxicity within the region of laser irradiation in vitro. To gain a better understanding of our gold nanoshells in the context of photothermal therapy, we developed a comprehensive mathematical model for heat transfer and experimentally validated this model by predicting the temperature as a function of time and position in our experimental setup. This model can be used to predict which parameters of our gold nanoshells can be manipulated to improve heat generation for tumor destruction. To our knowledge, our results represent the first ever use of block copolypeptide vesicles as the core material of gold nanoshells.

  7. Near-infrared light-triggered theranostics for tumor-specific enhanced multimodal imaging and photothermal therapy

    PubMed Central

    Wu, Bo; Wan, Bing; Lu, Shu-Ting; Deng, Kai; Li, Xiao-Qi; Wu, Bao-Lin; Li, Yu-Shuang; Liao, Ru-Fang; Huang, Shi-Wen; Xu, Hai-Bo

    2017-01-01

    The major challenge in current clinic contrast agents (CAs) and chemotherapy is the poor tumor selectivity and response. Based on the self-quench property of IR820 at high concentrations, and different contrast effect ability of Gd-DOTA between inner and outer of liposome, we developed “bomb-like” light-triggered CAs (LTCAs) for enhanced CT/MRI/FI multimodal imaging, which can improve the signal-to-noise ratio of tumor tissue specifically. IR820, Iohexol and Gd-chelates were firstly encapsulated into the thermal-sensitive nanocarrier with a high concentration. This will result in protection and fluorescence quenching. Then, the release of CAs was triggered by near-infrared (NIR) light laser irradiation, which will lead to fluorescence and MRI activation and enable imaging of inflammation. In vitro and in vivo experiments demonstrated that LTCAs with 808 nm laser irradiation have shorter T1 relaxation time in MRI and stronger intensity in FI compared to those without irradiation. Additionally, due to the high photothermal conversion efficiency of IR820, the injection of LTCAs was demonstrated to completely inhibit C6 tumor growth in nude mice up to 17 days after NIR laser irradiation. The results indicate that the LTCAs can serve as a promising platform for NIR-activated multimodal imaging and photothermal therapy. PMID:28670120

  8. Cancer Theranostics with Near-Infrared Light-Activatable Multimodal Nanoparticles

    PubMed Central

    Melancon, Marites P.; Zhou, Min; Li, Chun

    2011-01-01

    CONSPECTUS Nanomaterials that interact with light provide a unique opportunity for biophotonic nanomedicine. Multifunctional nanoparticles (NPs) that have strong and tunable surface plasmon resonance absorption in the near-infrared region combined with visibility with multiple imaging modalities (magnetic resonance imaging, nuclear imaging, and photoacoustic imaging) have great potential in image-guided therapies. These novel nanostructures, once introduced, are expected to home to solid tumors via the enhanced permeability and retention effect (a passive targeting mechanism) or via targeting ligands bound to their surfaces (an active targeting mechanism). The primary mode of action for photothermal conducting NPs is to convert photoenergy into heat, causing temperature in the treatment volume to be elevated above the thermal damage threshold, which results in irreversible cell killing. It is now recognized that this process, termed photothermal ablation therapy or PTA, although very effective, is unlikely to kill all tumor cells when used alone. In addition to PTA, photothermal conducting NPs can also efficiently trigger drug release and activate RNA interference. Such a multimodal approach, which permits simultaneous PTA therapy, chemotherapy, and therapeutic RNA interference, should provide an opportunity for complete eradication of residual disease. In this Account, we provide an up-to-date review of the synthesis and characterization, functionalization, and in vitro and in vivo evaluation of NIR light-activatable multifunctional nanostructures used for imaging and therapy, with an emphasis on hollow gold nanospheres, magnetic core–shell gold nanoshells, and semiconductor copper monosulfide NPs. We discuss three types novel drug delivery systems in which hollow gold nanospheres are used to mediate controlled drug release. PMID:21848277

  9. High-efficiency electroluminescence and amplified spontaneous emission from a thermally activated delayed fluorescent near-infrared emitter

    NASA Astrophysics Data System (ADS)

    Kim, Dae-Hyeon; D'Aléo, Anthony; Chen, Xian-Kai; Sandanayaka, Atula D. S.; Yao, Dandan; Zhao, Li; Komino, Takeshi; Zaborova, Elena; Canard, Gabriel; Tsuchiya, Youichi; Choi, Eunyoung; Wu, Jeong Weon; Fages, Frédéric; Brédas, Jean-Luc; Ribierre, Jean-Charles; Adachi, Chihaya

    2018-02-01

    Near-infrared organic light-emitting diodes and semiconductor lasers could benefit a variety of applications including night-vision displays, sensors and information-secured displays. Organic dyes can generate electroluminescence efficiently at visible wavelengths, but organic light-emitting diodes are still underperforming in the near-infrared region. Here, we report thermally activated delayed fluorescent organic light-emitting diodes that operate at near-infrared wavelengths with a maximum external quantum efficiency of nearly 10% using a boron difluoride curcuminoid derivative. As well as an effective upconversion from triplet to singlet excited states due to the non-adiabatic coupling effect, this donor-acceptor-donor compound also exhibits efficient amplified spontaneous emission. By controlling the polarity of the active medium, the maximum emission wavelength of the electroluminescence spectrum can be tuned from 700 to 780 nm. This study represents an important advance in near-infrared organic light-emitting diodes and the design of alternative molecular architectures for photonic applications based on thermally activated delayed fluorescence.

  10. EGF Functionalized Polymer-Coated Gold Nanoparticles Promote EGF Photostability and EGFR Internalization for Photothermal Therapy

    PubMed Central

    Silva, Catarina Oliveira; Petersen, Steffen B.; Reis, Catarina Pinto; Rijo, Patrícia; Molpeceres, Jesús; Fernandes, Ana Sofia; Gonçalves, Odete; Gomes, Andreia C.; Correia, Isabel; Vorum, Henrik; Neves-Petersen, Maria Teresa

    2016-01-01

    The application of functionalized nanocarriers on photothermal therapy for cancer ablation has wide interest. The success of this application depends on the therapeutic efficiency and biocompatibility of the system, but also on the stability and biorecognition of the conjugated protein. This study aims at investigating the hypothesis that EGF functionalized polymer-coated gold nanoparticles promote EGF photostability and EGFR internalization, making these conjugated particles suitable for photothermal therapy. The conjugated gold nanoparticles (100–200 nm) showed a plasmon absorption band located within the near-infrared range (650–900 nm), optimal for photothermal therapy applications. The effects of temperature, of polymer-coated gold nanoparticles and of UVB light (295nm) on the fluorescence properties of EGF have been investigated with steady-state and time-resolved fluorescence spectroscopy. The fluorescence properties of EGF, including the formation of Trp and Tyr photoproducts, is modulated by temperature and by the intensity of the excitation light. The presence of polymeric-coated gold nanoparticles reduced or even avoided the formation of Trp and Tyr photoproducts when EGF is exposed to UVB light, protecting this way the structure and function of EGF. Cytotoxicity studies of conjugated nanoparticles carried out in normal-like human keratinocytes showed small, concentration dependent decreases in cell viability (0–25%). Moreover, conjugated nanoparticles could activate and induce the internalization of overexpressed Epidermal Growth Factor Receptor in human lung carcinoma cells. In conclusion, the gold nanoparticles conjugated with Epidermal Growth Factor and coated with biopolymers developed in this work, show a potential application for near infrared photothermal therapy, which may efficiently destroy solid tumours, reducing the damage of the healthy tissue. PMID:27788212

  11. Au Nanoclusters Sensitized Black TiO2-x Nanotubes for Enhanced Photodynamic Therapy Driven by Near-Infrared Light.

    PubMed

    Yang, Dan; Gulzar, Arif; Yang, Guixin; Gai, Shili; He, Fei; Dai, Yunlu; Zhong, Chongna; Yang, Piaoping

    2017-12-01

    The low reactive oxygen species production capability and the shallow tissue penetration of excited light (UV) are still two barriers in photodynamic therapy (PDT). Here, Au cluster anchored black anatase TiO 2- x nanotubes (abbreviated as Au 25 /B-TiO 2- x NTs) are synthesized by gaseous reduction of anatase TiO 2 NTs and subsequent deposition of noble metal. The Au 25 /B-TiO 2- x NTs with thickness of about 2 nm exhibit excellent PDT performance. The reduction process increased the density of Ti 3+ on the surface of TiO 2 , which effectively depresses the recombination of electron and hole. Furthermore, after modification of Au 25 nanoclusters, the PDT efficiency is further enhanced owing to the changed electrical distribution in the composite, which forms a shallow potential well on the metal-TiO 2 interface to further hamper the recombination of electron and hole. Especially, the reduction of anatase TiO 2 can expend the light response range (UV) of TiO 2 to the visible and even near infrared (NIR) light region with high tissue penetration depth. When excited by NIR light, the nanoplatform shows markedly improved therapeutic efficacy attributed to the photocatalytic synergistic effect, and promotes separation or restrained recombination of electron and hole, which is verified by experimental results in vitro and in vivo. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Confocal Retinal Imaging Using a Digital Light Projector with a Near Infrared VCSEL Source

    PubMed Central

    Muller, Matthew S.; Elsner, Ann E.

    2018-01-01

    A custom near infrared VCSEL source has been implemented in a confocal non-mydriatic retinal camera, the Digital Light Ophthalmoscope (DLO). The use of near infrared light improves patient comfort, avoids pupil constriction, penetrates the deeper retina, and does not mask visual stimuli. The DLO performs confocal imaging by synchronizing a sequence of lines displayed with a digital micromirror device to the rolling shutter exposure of a 2D CMOS camera. Real-time software adjustments enable multiply scattered light imaging, which rapidly and cost-effectively emphasizes drusen and other scattering disruptions in the deeper retina. A separate 5.1″ LCD display provides customizable visible stimuli for vision experiments with simultaneous near infrared imaging. PMID:29899586

  13. Enhanced spatial near-infrared modulation of graphene-loaded perfect absorbers using plasmonic nanoslits.

    PubMed

    Cai, Yijun; Zhu, Jinfeng; Liu, Qing Huo; Lin, Timothy; Zhou, Jianyang; Ye, Longfang; Cai, Zhiping

    2015-12-14

    Modulating spatial near-infrared light for ultra-compact electro-optic devices is a critical issue in optical communication and imaging applications. To date, spatial near-infrared modulators based on graphene have been reported, but they showed limited modulation effects due to the relatively weak light-graphene interaction. In combination with graphene and metallic nanoslits, we design a kind of ultrathin near-infrared perfect absorber with enhanced spatial modulation effects and independence on a wide range of incident angles. The modulated spectral shift of central wavelength is up to 258.2 nm in the near-infrared range, which is more promising in applications than state-of-the-art devices. The modulation enhancement is attributed to the plasmonic nanoslit mode, in which the optical electric field is highly concentrated in the deep subwavelength scale and the light-graphene interaction is significantly strengthened. The physical insight is deeply revealed by a combination of equivalent circuit and electromagnetic field analysis. The design principles are not only crucial for spatial near-infrared modulators, but also provide a key guide for developing active near-infrared patch nanoantennas based on graphene.

  14. Gadolinium-Conjugated Gold Nanoshells for Multimodal Diagnostic Imaging and Photothermal Cancer Therapy

    PubMed Central

    Coughlin, Andrew J.; Ananta, Jeyarama S.; Deng, Nanfu; Larina, Irina V.; Decuzzi, Paolo

    2014-01-01

    Multimodal imaging offers the potential to improve diagnosis and enhance the specificity of photothermal cancer therapy. Toward this goal, we have engineered gadolinium-conjugated gold nanoshells and demonstrated that they enhance contrast for magnetic resonance imaging, X-Ray, optical coherence tomography, reflectance confocal microscopy, and two-photon luminescence. Additionally, these particles effectively convert near-infrared light to heat, which can be used to ablate cancer cells. Ultimately, these studies demonstrate the potential of gadolinium-nanoshells for image-guided photothermal ablation. PMID:24115690

  15. Hierarchical Models for Type Ia Supernova Light Curves in the Optical and Near Infrared

    NASA Astrophysics Data System (ADS)

    Mandel, Kaisey; Narayan, G.; Kirshner, R. P.

    2011-01-01

    I have constructed a comprehensive statistical model for Type Ia supernova optical and near infrared light curves. Since the near infrared light curves are excellent standard candles and are less sensitive to dust extinction and reddening, the combination of near infrared and optical data better constrains the host galaxy extinction and improves the precision of distance predictions to SN Ia. A hierarchical probabilistic model coherently accounts for multiple random and uncertain effects, including photometric error, intrinsic supernova light curve variations and correlations across phase and wavelength, dust extinction and reddening, peculiar velocity dispersion and distances. An improved BayeSN MCMC code is implemented for computing probabilistic inferences for individual supernovae and the SN Ia and host galaxy dust populations. I use this hierarchical model to analyze nearby Type Ia supernovae with optical and near infared data from the PAIRITEL, CfA3, and CSP samples and the literature. Using cross-validation to test the robustness of the model predictions, I find that the rms Hubble diagram scatter of predicted distance moduli is 0.11 mag for SN with optical and near infrared data versus 0.15 mag for SN with only optical data. Accounting for the dispersion expected from random peculiar velocities, the rms intrinsic prediction error is 0.08-0.10 mag for SN with both optical and near infrared light curves. I discuss results for the inferred intrinsic correlation structures of the optical-NIR SN Ia light curves and the host galaxy dust distribution captured by the hierarchical model. The continued observation and analysis of Type Ia SN in the optical and near infrared is important for improving their utility as precise and accurate cosmological distance indicators.

  16. Killing Cancer Cells with the Help of Infrared Light – Photoimmunotherapy

    Cancer.gov

    Near-infrared photoimmunotherapy uses an antibody–photoabsorber conjugate that binds to cancer cells. When near-infrared light is applied, the cells swell and then burst, causing the cancer cell to die. Photoimmunotherapy is in clinical trials in patients with inoperable tumors.

  17. Intraoperative near-infrared autofluorescence imaging of parathyroid glands.

    PubMed

    Ladurner, Roland; Sommerey, Sandra; Arabi, Nora Al; Hallfeldt, Klaus K J; Stepp, Herbert; Gallwas, Julia K S

    2017-08-01

    To identify parathyroid glands intraoperatively by exposing their autofluorescence using near-infrared light. Fluorescence imaging was carried out during minimally invasive and open parathyroid and thyroid surgery. After identification, the parathyroid glands as well as the surrounding tissue were exposed to near-infrared (NIR) light with a wavelength of 690-770 nm using a modified Karl Storz near-infrared/indocyanine green (NIR/ICG) endoscopic system. Parathyroid tissue was expected to show near-infrared autofluorescence, captured in the blue channel of the camera. Whenever possible the visual identification of parathyroid tissue was confirmed histologically. In preliminary investigations, using the original NIR/ICG endoscopic system we noticed considerable interference of light in the blue channel overlying the autofluorescence. Therefore, we modified the light source by interposing additional filters. In a second series, we investigated 35 parathyroid glands from 25 patients. Twenty-seven glands were identified correctly based on NIR autofluorescence. Regarding the extent of autofluorescence, there were no noticeable differences between parathyroid adenomas, hyperplasia and normal parathyroid glands. In contrast, thyroid tissue, lymph nodes and adipose tissue revealed no substantial autofluorescence. Parathyroid tissue is characterized by showing autofluorescence in the near-infrared spectrum. This effect can be used to distinguish parathyroid glands from other cervical tissue entities.

  18. Photothermal ablation cancer therapy using homogeneous CsxWO3 nanorods with broad near-infra-red absorption

    NASA Astrophysics Data System (ADS)

    Guo, Chongshen; Yin, Shu; Yu, Haijun; Liu, Shaoqin; Dong, Qiang; Goto, Takehiro; Zhang, Zhiwen; Li, Yaping; Sato, Tsugio

    2013-06-01

    Recently, photothermal ablation therapy (PTA) employing near-infrared radiation (NIR) has been extensively investigated as an emerging modality for cancer management. However, the clinical translation of this promising approach is limited by the lack of PTA agents with broad NIR absorption, low cost and high photothermal conversion efficiency. Herein, we have developed PEGylated homogeneous CsxWO3 nanorods (a mean size ~69.3 nm × 12.8 nm) with broad photo-absorption (780-2500 nm) as a novel NIR absorbent for PTA treatment of human cancer. The prepared CsxWO3 nanocrystals displayed strong near-infrared optical absorption with a high molar extinction coefficient (e.g. 4.8 × 1010 M-1 cm-1 at 980 nm), thus generated significant amounts of heat upon excitation with near-infrared light. The PTA study in two human carcinoma cell lines (i.e. A549 lung cancer cells and HeLa ovarian cancer cells) demonstrated that CsxWO3 nanorods can efficiently cause cell death via hyperthermia induced lysosome destruction, cytoskeleton protein degradation, DNA damage and thereafter cellular necrosis or apoptosis. Our study also confirmed the migration of healthy cells migrated from unirradiated areas to dead cell cycle, which is essential for tissue reconstruction and wound healing after photodestruction of tumor tissue. The prompted results reported in the current study imply the promising potential of CsxWO3 nanorods for application in PTA cancer therapy.Recently, photothermal ablation therapy (PTA) employing near-infrared radiation (NIR) has been extensively investigated as an emerging modality for cancer management. However, the clinical translation of this promising approach is limited by the lack of PTA agents with broad NIR absorption, low cost and high photothermal conversion efficiency. Herein, we have developed PEGylated homogeneous CsxWO3 nanorods (a mean size ~69.3 nm × 12.8 nm) with broad photo-absorption (780-2500 nm) as a novel NIR absorbent for PTA treatment of human cancer. The prepared CsxWO3 nanocrystals displayed strong near-infrared optical absorption with a high molar extinction coefficient (e.g. 4.8 × 1010 M-1 cm-1 at 980 nm), thus generated significant amounts of heat upon excitation with near-infrared light. The PTA study in two human carcinoma cell lines (i.e. A549 lung cancer cells and HeLa ovarian cancer cells) demonstrated that CsxWO3 nanorods can efficiently cause cell death via hyperthermia induced lysosome destruction, cytoskeleton protein degradation, DNA damage and thereafter cellular necrosis or apoptosis. Our study also confirmed the migration of healthy cells migrated from unirradiated areas to dead cell cycle, which is essential for tissue reconstruction and wound healing after photodestruction of tumor tissue. The prompted results reported in the current study imply the promising potential of CsxWO3 nanorods for application in PTA cancer therapy. Electronic supplementary information (ESI) available: EDS spectra, XRD patterns, TG plot of CsxWO3 nanorod are provided in the ESI. Additionally, linear correlations between NIR absorbance and CsxWO3-PEGS nanorod concentrations, cytotoxicity results, TEM image of intracellular distribution of CsxWO3-PEGS nanorods and fluorescence images can be found in the ESI. See DOI: 10.1039/c3nr01025b

  19. Electrowetting based infrared lens using ionic liquids

    NASA Astrophysics Data System (ADS)

    Hu, Xiaodong; Zhang, Shiguo; Liu, Yu; Qu, Chao; Lu, Liujin; Ma, Xiangyuan; Zhang, Xiaoping; Deng, Youquan

    2011-11-01

    We demonstrated an infrared variable focus ionic liquids lens using electrowetting, which could overcome the problems caused by use of water, e.g., evaporation and poor thermostability, while keeping good optical transparency in visible light and near-infrared region. Besides, the type of lens (convex or concave) could be tuned by applied voltage or refractive index of ILs used, and the transmittance was measured to exceed 90% over the spectrum of visible light and near-infrared. We believe this infrared variable focus ionic liquids lens has a great application prospect in both visible light and infrared image systems.

  20. Multiple wavelength light collimator and monitor

    NASA Technical Reports Server (NTRS)

    Gore, Warren J. (Inventor)

    2011-01-01

    An optical system for receiving and collimating light and for transporting and processing light received in each of N wavelength ranges, including near-ultraviolet, visible, near-infrared and mid-infrared wavelengths, to determine a fraction of light received, and associated dark current, in each wavelength range in each of a sequence of time intervals.

  1. [Near infrared light irradiator using halogen lamp].

    PubMed

    Ide, Yasuo

    2012-07-01

    The practical electric light bulb was invented by Thomas Alva Edison in 1879. Halogen lamp is the toughest and brightest electric light bulb. With light filter, it is used as a source of near infrared light. Super Lizer and Alphabeam are made as near infrared light irradiator using halogen lamp. The light emmited by Super Lizer is linear polarized near infrared light. The wave length is from 600 to 1,600 nm and strongest at about 1,000 nm. Concerning Super Lizer, there is evidence of analgesic effects and normalization of the sympathetic nervous system. Super Lizer has four types of probes. SG type is used for stellate ganglion irradiation. B type is used for narrow area irradiation. C and D types are for broad area irradiation. The output of Alphabeam is not polarized. The wave length is from 700 to 1,600 nm and the strongest length is about 1,000nm. Standard attachment is used for spot irradiation. Small attachment is used for stellate ganglion irradiation. Wide attachment is used for broad area irradiation. The effects of Alphabeam are thought to be similar to that of Super Lizer.

  2. Photothermal and mechanical stimulation of cells via dualfunctional nanohybrids

    NASA Astrophysics Data System (ADS)

    Chechetka, Svetlana A.; Doi, Motomichi; Pichon, Benoit P.; Bégin-Colin, Sylvie; Miyako, Eijiro

    2016-11-01

    Stimulating cells by light is an attractive technology to investigate cellular function and deliver innovative cell-based therapy. However, current techniques generally use poorly biopermeable light, which prevents broad applicability. Here, we show that a new type of composite nanomaterial, synthesized from multi-walled carbon nanotubes, magnetic iron nanoparticles, and polyglycerol, enables photothermal and mechanical control of Ca2+ influx into cells overexpressing transient receptor potential vanilloid type-2. The nanohybrid is simply operated by application of highly biotransparent near-infrared light and a magnetic field. The technology may revolutionize remote control of cellular function.

  3. Folate and Heptamethine Cyanine Modified Chitosan-Based Nanotheranostics for Tumor Targeted Near-Infrared Fluorescence Imaging and Photodynamic Therapy.

    PubMed

    Zhang, Yingying; Lv, Tingting; Zhang, Huijuan; Xie, Xiaodong; Li, Ziying; Chen, Haijun; Gao, Yu

    2017-07-10

    Folate (FA) and heptamethine cyanine (Cy7)-modified chitosan (CF7) was synthesized by click chemistry and its self-assembled nanoparticles (CF7Ns) were developed for tumor-specific imaging and photodynamic therapy. The characterization spectrum confirmed CF7 had a good FA and Cy7 conjugation efficacy. The diameter of CF7Ns measured by DLS was about 291.6 nm, and the morphology observed with AFM showed filamentous clusters of particles. The results of targeting ability of CF7Ns demonstrated enhanced targeting behaviors of CF7Ns compared with non-FA-modified nanoparticles C7Ns in FA receptor-positive HeLa cells. The cytotoxicity and cell apoptosis assay showed that CF7Ns under near-infrared light irradiation led to more apoptotic cell death in HeLa cells to improve the therapeutic efficacy. The mechanisms of the photodynamic effects of CF7Ns were demonstrated through measurement of intracellular reactive oxygen species and the apoptosis-related cytokines. These results suggested that CF7Ns are promising tumor targeting carriers for simultaneous fluorescence imaging and photodynamic therapy.

  4. Near-infrared spectroscopy can reveal increases in brain activity related to animal-assisted therapy.

    PubMed

    Morita, Yuka; Ebara, Fumio; Morita, Yoshimitsu; Horikawa, Etsuo

    2017-08-01

    [Purpose] Previous studies have indicated that animal-assisted therapy can promote recovery of psychological, social, and physiological function in mental disorders. This study was designed as a pilot evaluation of the use of near-infrared spectroscopy to objectively identify changes in brain activity that could mediate the effect of animal-assisted therapy. [Subjects and Methods] The participants were 20 healthy students (10 males and 10 females; age 19-21 years) of the Faculty of Agriculture, Saga University. Participants were shown a picture of a Tokara goat or shack (control) while prefrontal cortical oxygenated haemoglobin levels (representing neural activity) were measured by near-infrared spectroscopy. [Results] The prefrontal cortical near-infrared spectroscopy signal was significantly higher during viewing of the animal picture than during a rest condition or during viewing of the control picture. [Conclusion] Our results suggest that near-infrared spectroscopy can be used to objectively identify brain activity changes during human mentation regarding animals; furthermore, these preliminary results suggest the efficacy of animal-assisted therapy could be related to increased activation of the prefrontal cortex.

  5. A broadband LED source in visible to short-wave-infrared wavelengths for spectral tumor diagnostics

    NASA Astrophysics Data System (ADS)

    Hayashi, Daiyu; van Dongen, Anne Marie; Boerekamp, Jack; Spoor, Sandra; Lucassen, Gerald; Schleipen, Jean

    2017-06-01

    Various tumor types exhibit the spectral fingerprints in the absorption and reflection spectra in visible and especially in near- to short-wave-infrared wavelength ranges. For the purpose of spectral tumor diagnostics by means of diffuse reflectance spectroscopy, we developed a broadband light emitting diode (LED) source consisting of a blue LED for optical excitation, Lu3Al5O12:Ce3+,Cr3+ luminescent garnet for visible to near infrared emissions, and Bismuth doped GeO2 luminescent glass for near-infrared to short-wave infrared emissions. It emits broad-band light emissions continuously in 470-1600 nm with a spectral gap at 900-1000 nm. In comparison to the currently available broadband light sources like halogen lamps, high-pressure discharge lamps and super continuum lasers, the light sources of this paper has significant advantages for spectral tissue diagnostics in high-spectral stability, improved light coupling to optical fibers, potential in low light source cost and enabling battery-drive.

  6. Treating bulimia with hypnosis and low-level light therapy: a case report

    NASA Astrophysics Data System (ADS)

    Laser, Eleanor; Sassack, Michael

    2012-03-01

    This case report describes an effort to control bulimia nervosa by combining low-level laser therapy (LLLT)-the application of red and near-infrared light to specific body points-and hypnosis. A 29-year old female with a 14-year history of bulimia received one session of LLLT combined with hypnosis. Two weeks later, following a measurable decrease in bulimic episodes (purging), a session of psychotherapy and hypnosis was administered. Six months post-treatment, the patient has experienced a complete cessation of purging activities without recurrence. LLLT, when used in conjunction with hypnosis and psychotherapy, was effective in managing bulimia and may prove useful in treating other eating disorders.

  7. Effective Photothermal Chemotherapy Using Doxorubicin-Loaded Gold Nanospheres That Target EphB4 Receptors in Tumors

    PubMed Central

    You, Jian; Zhang, Rui; Xiong, Chiyi; Zhong, Meng; Melancon, Maritess; Gupta, Sanjay; Nick, Alpa M.; Sood, Anil K.; Li, Chun

    2012-01-01

    Photothermal ablation (PTA) is an emerging technique that uses near-infrared laser light-generated heat to destroy tumor cells. However, complete tumor eradication by PTA therapy alone is difficult because heterogeneous heat distribution can lead to sub-lethal thermal dose in some areas of the tumor. Successful PTA therapy requires selective delivery of photothermal conducting nanoparticles to mediate effective PTA of tumor cells, and the ability to combine PTA with other therapy modalities. Here, we synthesized multifunctional doxorubicin (DOX)-loaded hollow gold nanospheres (DOX@HAuNS) that target EphB4, a member of the Eph family of receptor tyrosine kinases overexpressed on the cell membrane of multiple tumors and angiogenic blood vessels. Increased uptake of targeted nanoparticles T-DOX@HAuNS was observed in three EphB4-positive tumors both in vitro and in vivo. In vivo release of DOX from DOX@HAuNS, triggered by near-infrared laser, was confirmed by dual radiotracer technique. Treatment with T-DOX@HAuNS followed by near-infrared laser irradiation resulted in significantly decreased tumor growth when compared to treatments with non-targeted DOX@HAuNS plus laser or HAuNS plus laser. The tumors in six of the eight mice treated with T-DOX@HAuNS plus laser regressed completely with only residual scar tissue by 22 days following injection, and none of the treatment groups experienced a loss in body weight. Together, our findings demonstrate that concerted chemo-photothermal therapy with a single nanodevice capable of mediating simultaneous PTA and local drug release may have promise as a new anticancer therapy. PMID:22865457

  8. Near-infrared light-mediated photodynamic/photothermal therapy nanoplatform by the assembly of Fe3O4 carbon dots with graphitic black phosphorus quantum dots

    PubMed Central

    Zhang, Ming; Wang, Wentao; Cui, Yingjun; Zhou, Ninglin; Shen, Jian

    2018-01-01

    Background Recently, combined photodynamic therapy (PDT) and photothermal therapy (PTT) has become a desired treatment for cancer. However, the development of economic, high-efficiency, and safe photosensitizers/photothermal agents remains a significant challenge. Methods A novel nanocomposite has been developed via the assembly of iron oxide carbon dot (Fe3O4-CDs) nanoparticles and black phosphorus quantum dots (genipin [GP]-polyglutamic acid [PGA]-Fe3O4-CDs@BPQDs), and this nanocomposite shows a broad light-absorption band and a photodegradable character. Results In vitro and in vivo assays indicated that GP-PGA-Fe3O4-CDs@BPQDs were highly biocompatible and exhibited excellent tumor-inhibition efficacy, due to the synergistic PTT and PDT via a near-infrared laser. Importantly, in vivo tumor magnetic resonance imaging (MRI) results illustrated that GP-PGA-Fe3O4-CDs@BPQDs can be specifically applied for enhanced T2 MRI of tumors. This work presents the first combined application of a PDT and PTT effect deriving from BPQDs and MRI from Fe3O4-CDs, which may promote utilization of black BPQDs in biomedicine. Conclusion As expected, GP-PGA-Fe3O4-CDs@BPQDs displayed a dramatically enhanced ability to destroy tumor cells, due to the synergistic combination of PTT and PDT. PMID:29785107

  9. Sub-100 nm Gold Nanomatryoshkas Improve Photo-thermal Therapy Efficacy in Large and Highly Aggressive Triple Negative Breast Tumors

    PubMed Central

    Bishnoi, Sandra; Urban, Alexander; Charron, Heather; Mitchell, Tamika; Shea, Martin; Nanda, Sarmistha; Schiff, Rachel; Halas, Naomi; Joshi, Amit

    2014-01-01

    There is an unmet need for efficient near-infrared photothermal transducers for the treatment of highly aggressive cancers and large tumors where the penetration of light can be substantially reduced, and the intra-tumoral nanoparticle transport is restricted due to the presence of hypoxic or nectrotic regions. We report the performance advantages obtained by sub 100 nm gold nanomatryushkas, comprising of concentric gold-silica-gold layers compared to conventional ~150 nm silica core gold nanoshells for photothermal therapy of triple negative breast cancer. We demonstrate that a 33% reduction in silica-core-gold-shell nanoparticle size, while retaining near-infrared plasmon resonance, and keeping the nanoparticle surface charge constant, results in a four to five fold tumor accumulation of nanoparticles following equal dose of injected gold for both sizes. The survival time of mice bearing large (>1000 mm3) and highly aggressive triple negative breast tumors is doubled for the nanomatryushka treatment group under identical photo-thermal therapy conditions. The higher absorption cross-section of a nanomatryoshka results in a higher efficiency of photonic to thermal energy conversion and coupled with 4-5X accumulation within large tumors results in superior therapy efficacy. PMID:25051221

  10. Review of transcranial photobiomodulation for major depressive disorder: targeting brain metabolism, inflammation, oxidative stress, and neurogenesis

    PubMed Central

    Cassano, Paolo; Petrie, Samuel R.; Hamblin, Michael R.; Henderson, Theodore A.; Iosifescu, Dan V.

    2016-01-01

    Abstract. We examined the use of near-infrared and red radiation (photobiomodulation, PBM) for treating major depressive disorder (MDD). While still experimental, preliminary data on the use of PBM for brain disorders are promising. PBM is low-cost with potential for wide dissemination; further research on PBM is sorely needed. We found clinical and preclinical studies via PubMed search (2015), using the following keywords: “near-infrared radiation,” “NIR,” “low-level light therapy,” “low-level laser therapy,” or “LLLT” plus “depression.” We chose clinically focused studies and excluded studies involving near-infrared spectroscopy. In addition, we used PubMed to find articles that examine the link between PBM and relevant biological processes including metabolism, inflammation, oxidative stress, and neurogenesis. Studies suggest the processes aforementioned are potentially effective targets for PBM to treat depression. There is also clinical preliminary evidence suggesting the efficacy of PBM in treating MDD, and comorbid anxiety disorders, suicidal ideation, and traumatic brain injury. Based on the data collected to date, PBM appears to be a promising treatment for depression that is safe and well-tolerated. However, large randomized controlled trials are still needed to establish the safety and effectiveness of this new treatment for MDD. PMID:26989758

  11. Near-infrared light emitting device using semiconductor nanocrystals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Supran, Geoffrey J.S.; Song, Katherine W.; Hwang, Gyuweon

    A near-infrared light emitting device can include semiconductor nanocrystals that emit at wavelengths beyond 1 .mu.m. The semiconductor nanocrystals can include a core and an overcoating on a surface of the core.

  12. Light up-conversion from near-infrared to blue using a photoresponsive organic light-emitting device

    NASA Astrophysics Data System (ADS)

    Chikamatsu, Masayuki; Ichino, Yoshiro; Takada, Noriyuki; Yoshida, Manabu; Kamata, Toshihide; Yase, Kiyoshi

    2002-07-01

    A photoresponsive organic light-emitting device combining blue-emitting organic electroluminescent (EL) diode with titanyl phthalocyanine as a near-infrared (IR) sensitive layer was fabricated. By irradiating near-IR light to the device, blue emission occurred in the lower drive voltage (between 5 and 12 V). The result indicates that the device acts as a light switch and/or an up-converter from near-IR light (1.6 eV) to blue (2.6 eV). The EL response times of rise and decay using a near-IR light trigger were 260 and 330 mus, respectively. At a higher voltage (above 12 V), enhancement of blue emission was observed with near-IR light irradiation. The ON/OFF ratio reached a maximum of 103.

  13. Silicon based near infrared photodetector using self-assembled organic crystalline nano-pillars

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ajiki, Yoshiharu, E-mail: yoshiharu-ajiki@ot.olympus.co.jp, E-mail: isao@i.u-tokyo.ac.jp; Kan, Tetsuo; Yahiro, Masayuki

    We propose a silicon (Si) based near-infrared photodetector using self-assembled organic crystalline nano-pillars, which were formed on an n-type Si substrate and were covered with an Au thin-film. These structures act as antennas for near-infrared light, resulting in an enhancement of the light absorption on the Au film. Because the Schottky junction is formed between the Au/n-type Si, the electron excited by the absorbed light can be detected as photocurrent. The optical measurement revealed that the nano-pillar structures enhanced the responsivity for the near-infrared light by 89 (14.5 mA/W) and 16 (0.433 mA/W) times compared with those of the photodetector without nano-pillarsmore » at the wavelengths of 1.2 and 1.3 μm, respectively. Moreover, no polarization dependency of the responsivity was observed, and the acceptable incident angle ranged from 0° to 30°. These broad responses were likely to be due to the organic nano-pillar structures' having variation in their orientation, which is advantageous for near-infrared detector uses.« less

  14. Near-Infrared Scintillation of Liquid Argon: Recent Results Obtained with the NIR Facility at Fermilab

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Escobar, C. O.; Rubinov, P.; Tilly, E.

    After a short review of previous attempts to observe and measure the near-infrared scintillation in liquid argon, we present new results obtained with NIR, a dedicated cryostat at the Fermilab Proton Assembly Building (PAB). The new results give confidence that the near-infrared light can be used as the much needed light signal in large liquid argon time projection chambers.11 pages,

  15. Femtowatt incoherent image conversion from mid-infrared light to near-infrared light

    NASA Astrophysics Data System (ADS)

    Huang, Nan; Liu, Hongjun; Wang, Zhaolu; Han, Jing; Zhang, Shuan

    2017-03-01

    We report on the experimental conversion imaging of an incoherent continuous-wave dim source from mid-infrared light to near-infrared light with a lowest input power of 31 femtowatt (fW). Incoherent mid-infrared images of light emission from a heat lamp bulb with an adjustable power supply at window wavelengths ranging from 2.9 µm to 3.5 µm are used for upconversion. The sum-frequency generation is realized in a laser cavity with the resonant wavelength of 1064 nm pumped by an LD at 806 nm built around a periodically poled lithium niobate (PPLN) crystal. The converted infrared image in the wavelength range ~785 nm with a resolution of about 120  ×  70 is low-noise detected using a silicon-based camera. By optimizing the system parameters, the upconversion quantum efficiency is predicted to be 28% for correctly polarized, on-axis and phase-matching light.

  16. A light therapy for treating Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Wang, Xue; Han, Mengmeng; Wang, Qiyan; Zeng, Yuhui; Meng, Qingqiang; Zhang, Jun; Wei, Xunbin

    2017-02-01

    It is generally believed that there are some connections between Alzheimer's disease and amyloid protein plaques in the brain. The typical symptoms of Alzheimer's disease are memory loss, language disorders, mood swings, loss of motivation and behavioral issues. Currently, the main therapeutic method is pharmacotherapy, which may temporarily reduce symptoms, but has many side effects. Infrared light therapy has been studied in a range of single and multiple irradiation protocols in previous studies and was found beneficial for neuropathology. In our research we have studied the effect of infrared light on Alzheimer's disease through transgenic mouse model. We designed an experimental apparatus for treating mice, which primarily included a therapeutic box and a LED array, which emitted infrared light. After the treatment, we assessed the effects of infrared light by performing two tests: cognitive performance of mice in Morris water maze, and plaque load by immunofluorescence analysis. Immunofluorescence analysis was based on measuring the quantity of plaques in mouse brain slices. Our results show that infrared therapy is able to improve cognitive performance in the mouse model. It might provide a novel and safe way to treat Alzheimer's disease.

  17. Super enhanced permeability and retention (SUPR) effects in tumors following near infrared photoimmunotherapy

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hisataka; Choyke, Peter L.

    2016-06-01

    To date, the delivery of nano-sized therapeutic agents to cancers largely relies on enhanced permeability and retention (EPR) effects that are caused by the leaky nature of cancer vasculature. However, nano-sized agents delivered in this way have demonstrated limited success in oncology due to the relatively small magnitude of the EPR effect. For achieving superior delivery of nano-sized agents, super-enhanced permeability and retention (SUPR) effects are needed. Near infrared photo-immunotherapy (NIR-PIT) is a recently reported therapy that treats tumors with light therapy and subsequently causes an increase in nano-drug delivery up to 24-fold compared with untreated tumors in which only the EPR effect is present. SUPR effects could enhance delivery into tumor beds of a wide variety of nano-sized agents including particles, antibodies, and protein binding small molecular agents. Therefore, taking advantage of the SUPR effects after NIR-PIT may be a promising avenue to utilize a wide variety of nano-drugs in a highly effective manner.

  18. Pyropheophorbide A and c(RGDyK) comodified chitosan-wrapped upconversion nanoparticle for targeted near-infrared photodynamic therapy.

    PubMed

    Zhou, Aiguo; Wei, Yanchun; Wu, Baoyan; Chen, Qun; Xing, Da

    2012-06-04

    Near-infrared (NIR)-to-visible upconversion nanoparticle (UCNP) has shown promising prospects in photodynamic therapy (PDT) as a drug carrier or energy donor. In this work, a photosensitizer pyropheophorbide a (Ppa) and RGD peptide c(RGDyK) comodified chitosan-wrapped NaYF(4):Yb/Er upconversion nanoparticle UCNP-Ppa-RGD was developed for targeted near-infrared photodynamic therapy. The properties of UCNP-Ppa-RGD, such as morphology, stability, optical spectroscopy and singlet oxygen generation efficiency, were investigated. The results show that covalently linked pyropheophorbide a molecule not only is stable but also retains its spectroscopic and functional properties. In vitro studies confirm a stronger targeting specificity of UCNP-Ppa-RGD to integrin α(v)β(3)-positive U87-MG cells compared with that in the corresponding negative group. The photosensitizer-attached nanostructure exhibited low dark toxicity and high phototoxicity against cancer cells upon 980 nm laser irradiation at an appropriate dosage. These results represent the first demonstration of a highly stable and efficient photosensitizer modified upconversion nanostructure for targeted near-infrared photodynamic therapy of cancer cells. The novel UCNP-Ppa-RGD nanoparticle may provide a powerful alternative for near-infrared photodynamic therapy with an improved tumor targeting specificity.

  19. Near-infrared branding efficiently correlates light and electron microscopy.

    PubMed

    Bishop, Derron; Nikić, Ivana; Brinkoetter, Mary; Knecht, Sharmon; Potz, Stephanie; Kerschensteiner, Martin; Misgeld, Thomas

    2011-06-05

    The correlation of light and electron microscopy of complex tissues remains a major challenge. Here we report near-infrared branding (NIRB), which facilitates such correlation by using a pulsed, near-infrared laser to create defined fiducial marks in three dimensions in fixed tissue. As these marks are fluorescent and can be photo-oxidized to generate electron contrast, they can guide re-identification of previously imaged structures as small as dendritic spines by electron microscopy.

  20. Lipogels responsive to near-infrared light for the triggered release of therapeutic agents.

    PubMed

    Martín-Saavedra, Francisco; Ruiz-Hernández, Eduardo; Escudero-Duch, Clara; Prieto, Martín; Arruebo, Manuel; Sadeghi, Negar; Deckers, Roel; Storm, Gert; Hennink, Wim E; Santamaría, Jesús; Vilaboa, Nuria

    2017-10-01

    Here we report a composite system based on fibrin hydrogels that incorporate in their structure near-infrared (NIR) responsive nanomaterials and thermosensitive liposomes (TSL). Polymerized fibrin networks entrap simultaneously gold-based nanoparticles (NPs) capable of transducing NIR photon energy into heat, and lysolipid-incorporated TSL (LTSL) loaded with doxorubicin hydrochloride (DOX). NIR irradiation of the resulting hydrogels (referred to as "lipogels") with 808nm laser light increased the temperature of the illuminated areas, leading to the release of the liposomal cargo. Levels of DOX that release from the "smart" composites were dependent on the concentration of NIR nanotransducers loaded in the lipogel, the intensity of the electromagnetic energy deposited and the irradiation regime. Released DOX retained its bioactivity, as shown in cultures of epithelial carcinoma cells. Finally, the developed drug delivery platform was refined by using NIR-photoabsorbers based on copper sulfide NPs to generate completely biodegradable composites as well as through the incorporation of cholesterol (Ch) in LTSL formulation, which lessens leakiness of the liposomal cargo at physiological temperature. This remotely controlled system may suit well for those therapies that require precise control over the dose of delivered drug in a defined spatiotemporal framework. Hydrogels composed of fibrin embedding nanoparticles responsive to near infrared (NIR) energy and thermosensitive liposomes loaded with doxorubicin hydrochloride (DOX), were prepared by in situ polymerization. NIR-light irradiation of these constructs, referred to as "NIR responsive lipogels", results in the controlled release of DOX to the surrounding medium. This technology may use fully degradable components and can preserve the bioactivity of liposomal cargo after remote triggering to finely regulate the dose and bioavailability of delivered payloads. NIR responsive lipogels technology overcomes the limitations of drug release systems based on the combination of liposomes and degradable polymeric materials, which in many cases lead to insufficient release at therapy onset or to overdose during high degradation period. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. Chlorophyll f and chlorophyll d are produced in the cyanobacterium Chlorogloeopsis fritschii when cultured under natural light and near-infrared radiation.

    PubMed

    Airs, R L; Temperton, B; Sambles, C; Farnham, G; Skill, S C; Llewellyn, C A

    2014-10-16

    We report production of chlorophyll f and chlorophyll d in the cyanobacterium Chlorogloeopsis fritschii cultured under near-infrared and natural light conditions. C. fritschii produced chlorophyll f and chlorophyll d when cultured under natural light to a high culture density in a 20 L bubble column photobioreactor. In the laboratory, the ratio of chlorophyll f to chlorophyll a changed from 1:15 under near-infrared, to an undetectable level of chlorophyll f under artificial white light. The results provide support that chlorophylls f and d are both red-light inducible chlorophylls in C. fritschii. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  2. Upconversion Nanoparticles for Photodynamic Therapy and Other Cancer Therapeutics

    PubMed Central

    Wang, Chao; Cheng, Liang; Liu, Zhuang

    2013-01-01

    Photodynamic therapy (PDT) is a non-invasive treatment modality for a variety of diseases including cancer. PDT based on upconversion nanoparticles (UCNPs) has received much attention in recent years. Under near-infrared (NIR) light excitation, UCNPs are able to emit high-energy visible light, which can activate surrounding photosensitizer (PS) molecules to produce singlet oxygen and kill cancer cells. Owing to the high tissue penetration ability of NIR light, NIR-excited UCNPs can be used to activate PS molecules in much deeper tissues compared to traditional PDT induced by visible or ultraviolet (UV) light. In addition to the application of UCNPs as an energy donor in PDT, via similar mechanisms, they could also be used for the NIR light-triggered drug release or activation of 'caged' imaging or therapeutic molecules. In this review, we will summarize the latest progresses regarding the applications of UCNPs for photodynamic therapy, NIR triggered drug and gene delivery, as well as several other UCNP-based cancer therapeutic approaches. The future prospects and challenges in this emerging field will be also discussed. PMID:23650479

  3. Cyanine-Anchored Silica Nanochannels for Light-Driven Synergistic Thermo-Chemotherapy.

    PubMed

    Deng, Yibin; Huang, Li; Yang, Hong; Ke, Hengte; He, Hui; Guo, Zhengqing; Yang, Tao; Zhu, Aijun; Wu, Hong; Chen, Huabing

    2017-02-01

    Smart nanoparticles are increasingly important in a variety of applications such as cancer therapy. However, it is still a major challenge to develop light-responsive nanoparticles that can maximize the potency of synergistic thermo-chemotherapy under light irradiation. Here, spatially confined cyanine-anchored silica nanochannels loaded with chemotherapeutic doxorubicin (CS-DOX-NCs) for light-driven synergistic cancer therapy are introduced. CS-DOX-NCs possess a J-type aggregation conformation of cyanine dye within the nanochannels and encapsulate doxorubicin through the π-π interaction with cyanine dye. Under near-infrared light irradiation, CS-DOX-NCs produce the enhanced photothermal conversion efficiency through the maximized nonradiative transition of J-type Cypate aggregates, trigger the light-driven drug release through the destabilization of temperature-sensitive π-π interaction, and generate the effective intracellular translocation of doxorubicin from the lysosomes to cytoplasma through reactive oxygen species-mediated lysosomal disruption, thereby causing the potent in vivo hyperthermia and intracellular trafficking of drug into cytoplasma at tumors. Moreover, CS-DOX-NCs possess good resistance to photobleaching and preferable tumor accumulation, facilitating severe photoinduced cell damage, and subsequent synergy between photothermal and chemotherapeutic therapy with tumor ablation. These findings provide new insights of light-driven nanoparticles for synergistic cancer therapy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Topological Crystalline Insulator SnTe/Si Vertical Heterostructure Photodetectors for High-Performance Near-Infrared Detection.

    PubMed

    Zhang, Hongbin; Man, Baoyuan; Zhang, Qi

    2017-04-26

    Due to the gapless surface state and narrow bulk band gap, the light absorption of topological crystalline insulators covers a broad spectrum ranging from terahertz to infrared, revealing promising applications in new generation optoelectronic devices. To date, the photodetectors based on topological insulators generally suffer from a large dark current and a weaker photocurrent especially under the near-infrared lights, which severely limits the practical application of devices. Owing to the lower excitation energy of infrared lights, the photodetection application of topological crystalline insulators in the near-infrared region relies critically on understanding the preparation and properties of their heterostructures. Herein, we fabricate the high-quality topological crystalline insulator SnTe film/Si vertical heterostructure by a simple physical vapor deposition process. The resultant heterostructure exhibits an excellent diode characteristic, enabling the construction of high-performance near-infrared photodetectors. The built-in electric field at SnTe/Si interface enhances the absorption efficiency of near-infrared lights and greatly facilitates the separation of photogenerated carriers, making the device capable of operating as a self-driven photodetector. The as-grown SnTe film acts as the hole transport layer in heterostructure photodetectors, promoting the transport of holes to electrode and reducing electron-hole recombination effectively. These merits enable the SnTe/Si heterostructure photodetector to have a high responsivity of 2.36 AW -1 , a high detectivity of 1.54 × 10 14 Jones, and a large bandwidth of 10 4 Hz in the near-infrared wavelength, which makes the detector have a promising market in novel device applications.

  5. Experimental study of near-field light collection efficiency of aperture fiber probe at near-infrared wavelengths.

    PubMed

    Tsumori, Nobuhiro; Takahashi, Motoki; Sakuma, Yoshiki; Saiki, Toshiharu

    2011-10-10

    We examined the near-field collection efficiency of near-infrared radiation for an aperture probe. We used InAs quantum dots as ideal point light sources with emission wavelengths ranging from 1.1 to 1.6 μm. We experimentally investigated the wavelength dependence of the collection efficiency and compared the results with computational simulations that modeled the actual probe structure. The observed degradation in the collection efficiency is attributed to the cutoff characteristics of the gold-clad tapered waveguide, which approaches an ideal conductor at near-infrared wavelengths. © 2011 Optical Society of America

  6. A near-infrared light responsive c-di-GMP module-based AND logic gate in Shewanella oneidensis.

    PubMed

    Hu, Yidan; Wu, Yichao; Mukherjee, Manisha; Cao, Bin

    2017-01-31

    A novel, biofilm-based AND logic gate was constructed in Shewanella oneidensis through a near-infrared (NIR) light responsive c-di-GMP module. The logic gate was demonstrated in microbial fuel cells with isopropyl β-d-thiogalactoside (IPTG) and NIR light as the inputs and electrical signals as the output.

  7. Comparative effectiveness of light emitting diodes (LEDs) and Lasers in near infrared photoimmunotherapy

    PubMed Central

    Sato, Kazuhide; Watanabe, Rira; Hanaoka, Hirofumi; Nakajima, Takahito; Choyke, Peter L.; Kobayashi, Hisataka

    2016-01-01

    Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of antibodies for targeting tumors with the toxicity induced by photosensitizers after exposure to near infrared (NIR) light. Herein we compare two NIR-light sources; light emitting diodes (LEDs) and Lasers, for their effectiveness in NIR-PIT. A photosensitizer, IRDye-700DX, conjugated to panitumumab (pan-IR700), was incubated with EGFR-expressing A431 and MDA-MB-468-luc cells. NIR-light was provided by LEDs or Lasers at the same light dose. Laser-light produced more cytotoxicity and greater reductions in IR700-fluorescence intensity than LED-light. Laser-light also produced more cytotoxicity in vivo in both cell lines. Assessment of super-enhanced permeability and retention (SUPR) effects were stronger with Laser than LED. These results suggest that Laser-light produced significantly more cytotoxic effects compared to LEDs. Although LED is less expensive, Laser-light produces superior results in NIR-PIT. PMID:26885688

  8. Comparative effectiveness of light emitting diodes (LEDs) and Lasers in near infrared photoimmunotherapy.

    PubMed

    Sato, Kazuhide; Watanabe, Rira; Hanaoka, Hirofumi; Nakajima, Takahito; Choyke, Peter L; Kobayashi, Hisataka

    2016-03-22

    Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of antibodies for targeting tumors with the toxicity induced by photosensitizers after exposure to near infrared (NIR) light. Herein we compare two NIR-light sources; light emitting diodes (LEDs) and Lasers, for their effectiveness in NIR-PIT. A photosensitizer, IRDye-700DX, conjugated to panitumumab (pan-IR700), was incubated with EGFR-expressing A431 and MDA-MB-468-luc cells. NIR-light was provided by LEDs or Lasers at the same light dose. Laser-light produced more cytotoxicity and greater reductions in IR700-fluorescence intensity than LED-light. Laser-light also produced more cytotoxicity in vivo in both cell lines. Assessment of super-enhanced permeability and retention (SUPR) effects were stronger with Laser than LED. These results suggest that Laser-light produced significantly more cytotoxic effects compared to LEDs. Although LED is less expensive, Laser-light produces superior results in NIR-PIT.

  9. First light observations with TIFR Near Infrared Imaging Camera (TIRCAM-II)

    NASA Astrophysics Data System (ADS)

    Ojha, D. K.; Ghosh, S. K.; D'Costa, S. L. A.; Naik, M. B.; Sandimani, P. R.; Poojary, S. S.; Bhagat, S. B.; Jadhav, R. B.; Meshram, G. S.; Bakalkar, C. B.; Ramaprakash, A. N.; Mohan, V.; Joshi, J.

    TIFR near infrared imaging camera (TIRCAM-II) is based on the Aladdin III Quadrant InSb focal plane array (512×512 pixels; 27.6 μm pixel size; sensitive between 1 - 5.5 μm). TIRCAM-II had its first engineering run with the 2 m IUCAA telescope at Girawali during February - March 2011. The first light observations with TIRCAM-II were quite successful. Several infrared standard with TIRCAM-II were quite successful. Several infrared standard stars, the Trapezium Cluster in Orion region, McNeil's nebula, etc., were observed in the J, K and in a narrow-band at 3.6 μm (nbL). In the nbL band, some bright stars could be detected from the Girawali site. The performance of TIRCAM-II is discussed in the light of preliminary observations in near infrared bands.

  10. Contribution of infrared microscopy to studies of fluid inclusions hosted in some opaque ore minerals: possibilities, limitations, and perspectives

    NASA Astrophysics Data System (ADS)

    Lüders, Volker

    2017-06-01

    During the past two decades, several studies of fluid inclusions hosted in some opaque ore minerals using near-infrared microscopy have been performed. Results indicated that this method can be applied to several sulfidic ores and metal oxides depending on their electronic band structures and infrared-active vibration modes. Infrared transmittance of individual ore minerals can be best characterized using Fourier transform infrared spectroscopy. Infrared microscopic observations are limited to the near-infrared region to about 2.3 μm depending on the IR sensitivity of the IR camera. The trace element content in ore minerals can be another limiting factor for optical observations in near-infrared light. Still, IR transmittance gradually decreases upon heating caused by shifting of IR absorption edges for higher wavelengths. Possibilities and limitations of studying fluid inclusions hosted in opaque minerals by near-infrared light microthermometry and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are discussed.

  11. Infrared and visible fusion face recognition based on NSCT domain

    NASA Astrophysics Data System (ADS)

    Xie, Zhihua; Zhang, Shuai; Liu, Guodong; Xiong, Jinquan

    2018-01-01

    Visible face recognition systems, being vulnerable to illumination, expression, and pose, can not achieve robust performance in unconstrained situations. Meanwhile, near infrared face images, being light- independent, can avoid or limit the drawbacks of face recognition in visible light, but its main challenges are low resolution and signal noise ratio (SNR). Therefore, near infrared and visible fusion face recognition has become an important direction in the field of unconstrained face recognition research. In this paper, a novel fusion algorithm in non-subsampled contourlet transform (NSCT) domain is proposed for Infrared and visible face fusion recognition. Firstly, NSCT is used respectively to process the infrared and visible face images, which exploits the image information at multiple scales, orientations, and frequency bands. Then, to exploit the effective discriminant feature and balance the power of high-low frequency band of NSCT coefficients, the local Gabor binary pattern (LGBP) and Local Binary Pattern (LBP) are applied respectively in different frequency parts to obtain the robust representation of infrared and visible face images. Finally, the score-level fusion is used to fuse the all the features for final classification. The visible and near infrared face recognition is tested on HITSZ Lab2 visible and near infrared face database. Experiments results show that the proposed method extracts the complementary features of near-infrared and visible-light images and improves the robustness of unconstrained face recognition.

  12. Theranostic Multibranched Gold Nanoantennas for Cancer Diagnostics via Surface Enhanced Raman Spectroscopy and Photothermal Therapeutics

    NASA Astrophysics Data System (ADS)

    Weinstein-Webb, Joseph A.

    Cancer is the second leading cause of death globally according to the World Health Organization. Especially dangerous and lethal are the breast cancers that have genetic mutations for surface receptors utilized in drug therapy. This resistance calls for new and innovative treatments that be optimized for cancers based on an individual patient basis/cancer phenotype. Nanoparticle based diagnostics and therapeutics have recently emerged as a novel platform for management and mitigation of cancer at all stages. Gold nanostructures, specifically, have multiple characteristics that make them ideal for cancer theranostics including: (i) high biocompatibility, (ii) ease of bioconjugation, (iii) ability to tune their plasmon resonance to absorb tissue penetrating near infrared light, (iv) their use as contrast agents, and (v) ability to convert light to heat when excited at the plasmon resonance for photothermal ablation of cancer cells. Further, due to their adaptability as a platform, the nanoparticles affect the battle against cancer in multiple different strategies. These theranostic gold nanoprobes can be incorporated into point of care diagnostic (POCD) systems for biomarker detection, used as theranostic probes to delivery multiplex SERS receptor imaging and photothermal therapy or be involved in future immunotherapy treatments. In this work we demonstrate the use of near-infrared light absorbing multibranched gold nanoantennas (MGNs) to simultaneously deliver diagnostic and therapeutic (theranostic) capabilities in cancer models. More aggressive cancer cell lines require approaches that are versatile and multifunctional, and the possibilities for the usage in diagnostics or therapeutics for these theranostic MGNs are abundant.

  13. A Highly Efficient and Photostable Photosensitizer with Near-Infrared Aggregation-Induced Emission for Image-Guided Photodynamic Anticancer Therapy.

    PubMed

    Wu, Wenbo; Mao, Duo; Hu, Fang; Xu, Shidang; Chen, Chao; Zhang, Chong-Jing; Cheng, Xiamin; Yuan, Youyong; Ding, Dan; Kong, Deling; Liu, Bin

    2017-09-01

    Photodynamic therapy (PDT), which relies on photosensitizers (PS) and light to generate reactive oxygen species to kill cancer cells or bacteria, has attracted much attention in recent years. PSs with both bright emission and efficient singlet oxygen generation have also been used for image-guided PDT. However, simultaneously achieving effective 1 O 2 generation, long wavelength absorption, and stable near-infrared (NIR) emission with low dark toxicity in a single PS remains challenging. In addition, it is well known that when traditional PSs are made into nanoparticles, they encounter quenched fluorescence and reduced 1 O 2 production. In this contribution, these challenging issues have been successfully addressed through designing the first photostable photosensitizer with aggregation-induced NIR emission and very effective 1 O 2 generation in aggregate state. The yielded nanoparticles show very effective 1 O 2 generation, bright NIR fluorescence centered at 820 nm, excellent photostability, good biocompatibility, and negligible dark in vivo toxicity. Both in vitro and in vivo experiments prove that the nanoparticles are excellent candidates for image-guided photodynamic anticancer therapy. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Subsurface thermal coagulation of tissues using near infrared lasers

    NASA Astrophysics Data System (ADS)

    Chang, Chun-Hung Jack

    Noninvasive laser therapy is currently limited primarily to cosmetic dermatological applications such as skin resurfacing, hair removal, tattoo removal and treatment of vascular birthmarks. In order to expand applications of noninvasive laser therapy, deeper optical penetration of laser radiation in tissue as well as more aggressive cooling of the tissue surface is necessary. The near-infrared laser wavelength of 1075 nm was found to be the optimal laser wavelength for creation of deep subsurface thermal lesions in liver tissue, ex vivo, with contact cooling, preserving a surface tissue layer of 2 mm. Monte Carlo light transport, heat transfer, and Arrhenius integral thermal damage simulations were conducted at this wavelength, showing good agreement between experiment and simulations. Building on the initial results, our goal is to develop new noninvasive laser therapies for application in urology, specifically for treatment of female stress urinary incontinence (SUI). Various laser balloon probes including side-firing and diffusing fibers were designed and tested for both transvaginal and transurethral approaches to treatment. The transvaginal approach showed the highest feasibility. To further increase optical penetration depth, various types and concentrations of optical clearing agents were also explored. Three cadavers studies were performed to investigate and demonstrate the feasibility of laser treatment for SUI.

  15. Two-dimensional singlet oxygen imaging with its near-infrared luminescence during photosensitization

    PubMed Central

    Hu, Bolin; Zeng, Nan; Liu, Zhiyi; Ji, Yanhong; Xie, Weidong; Peng, Qing; Zhou, Yong; He, Yonghong; Ma, Hui

    2011-01-01

    Photodynamic therapy is a promising cancer treatment that involves activation of photosensitizer by visible light to create singlet oxygen. This highly reactive oxygen species is believed to induce cell death and tissue destruction in PDT. Our approach used a near-infrared area CCD with high quantum efficiency to detect singlet oxygen by its 1270-nm luminescence. Two-dimensional singlet oxygen images with its near-infrared luminescence during photosensitization could be obtained with a CCD integration time of 1 s, without scanning. Thus this system can produce singlet oxygen luminescence images faster and achieve more accurate measurements in comparison to raster-scanning methods. The experimental data show a linear relationship between the singlet oxygen luminescence intensity and sample concentration. This method provides a detection sensitivity of 0.0181 μg/ml (benzoporphyrin derivative monoacid ring A dissolved in ethanol) and a spatial resolution better than 50 μm. A pilot study was conducted on a total of six female Kunming mice. The results from this study demonstrate the system's potential for in vivo measurements. Further experiments were carried out on two tumor-bearing nude mice. Singlet oxygen luminescence images were acquired from the tumor-bearing nude mouse with intravenous injection of BPD-MA, and the experimental results showed real-time singlet oxygen signal depletion as a function of the light exposure. PMID:21280909

  16. Near-infrared light stimuli-responsive synergistic therapy nanoplatforms based on the coordination of tellurium-containing block polymer and cisplatin for cancer treatment.

    PubMed

    Li, Feng; Li, Tianyu; Cao, Wei; Wang, Lu; Xu, Huaping

    2017-07-01

    Cisplatin (CDDP) has received worldwide approval for clinical use in the past decades. However, its development in cancer chemotherapy was overshadowed by severe side effects and drug resistance. Herein, we developed a CDDP drug delivery system with high encapsulation efficiency and near-infrared light stimuli-responsive drug release properties based on the coordination of novel tellurium-containing block polymer (PEG-PUTe-PEG) and CDDP. The nanocarriers made from PEG-PUTe-PEG were loaded with CDDP and indocyanine green (ICG) simultaneously. The coordination chemistry between CDDP and tellurium guaranteed the nanocarrier a high stability in plasma and prolonged circulation time in vivo by reducing possible penetration of water molecule into the nanoparticles. Under the stimuli of a near-infrared laser, an amount of ROS can be generated by irradiation of ICG. The tellurium is easily oxidized by ROS because of the low electronegativity of tellurium. The CDDP could be rapidly released from the nanocarriers along with the oxidation of the tellurium at the tumor sites as the oxidized tellurium will weaken the coordination interaction with CDDP. In addition, the encapsulated ICG played a synergistic antitumor effect through photothermal effect with mild laser irradiation. The integrated strategy achieved higher antitumor efficacy and showed minimal side effects compared with the CDDP alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser

    PubMed Central

    Wang, Xinlong; Tian, Fenghua; Soni, Sagar S.; Gonzalez-Lima, F.; Liu, Hanli

    2016-01-01

    Photobiomodulation, also known as low-level laser/light therapy (LLLT), refers to the use of red-to-near-infrared light to stimulate cellular functions for physiological or clinical benefits. The mechanism of LLLT is assumed to rely on photon absorption by cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial respiratory chain that catalyzes the reduction of oxygen for energy metabolism. In this study, we used broadband near-infrared spectroscopy (NIRS) to measure the LLLT-induced changes in CCO and hemoglobin concentrations in human forearms in vivo. Eleven healthy participants were administered with 1064-nm laser and placebo treatments on their right forearms. The spectroscopic data were analyzed and fitted with wavelength-dependent, modified Beer-Lambert Law. We found that LLLT induced significant increases of CCO concentration (Δ[CCO]) and oxygenated hemoglobin concentration (Δ[HbO]) on the treated site as the laser energy dose accumulated over time. A strong linear interplay between Δ[CCO] and Δ[HbO] was observed for the first time during LLLT, indicating a hemodynamic response of oxygen supply and blood volume closely coupled to the up-regulation of CCO induced by photobiomodulation. These results demonstrate the tremendous potential of broadband NIRS as a non-invasive, in vivo means to study mechanisms of photobiomodulation and perform treatment evaluations of LLLT. PMID:27484673

  18. Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser

    NASA Astrophysics Data System (ADS)

    Wang, Xinlong; Tian, Fenghua; Soni, Sagar S.; Gonzalez-Lima, F.; Liu, Hanli

    2016-08-01

    Photobiomodulation, also known as low-level laser/light therapy (LLLT), refers to the use of red-to-near-infrared light to stimulate cellular functions for physiological or clinical benefits. The mechanism of LLLT is assumed to rely on photon absorption by cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial respiratory chain that catalyzes the reduction of oxygen for energy metabolism. In this study, we used broadband near-infrared spectroscopy (NIRS) to measure the LLLT-induced changes in CCO and hemoglobin concentrations in human forearms in vivo. Eleven healthy participants were administered with 1064-nm laser and placebo treatments on their right forearms. The spectroscopic data were analyzed and fitted with wavelength-dependent, modified Beer-Lambert Law. We found that LLLT induced significant increases of CCO concentration (Δ[CCO]) and oxygenated hemoglobin concentration (Δ[HbO]) on the treated site as the laser energy dose accumulated over time. A strong linear interplay between Δ[CCO] and Δ[HbO] was observed for the first time during LLLT, indicating a hemodynamic response of oxygen supply and blood volume closely coupled to the up-regulation of CCO induced by photobiomodulation. These results demonstrate the tremendous potential of broadband NIRS as a non-invasive, in vivo means to study mechanisms of photobiomodulation and perform treatment evaluations of LLLT.

  19. Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser.

    PubMed

    Wang, Xinlong; Tian, Fenghua; Soni, Sagar S; Gonzalez-Lima, F; Liu, Hanli

    2016-08-03

    Photobiomodulation, also known as low-level laser/light therapy (LLLT), refers to the use of red-to-near-infrared light to stimulate cellular functions for physiological or clinical benefits. The mechanism of LLLT is assumed to rely on photon absorption by cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial respiratory chain that catalyzes the reduction of oxygen for energy metabolism. In this study, we used broadband near-infrared spectroscopy (NIRS) to measure the LLLT-induced changes in CCO and hemoglobin concentrations in human forearms in vivo. Eleven healthy participants were administered with 1064-nm laser and placebo treatments on their right forearms. The spectroscopic data were analyzed and fitted with wavelength-dependent, modified Beer-Lambert Law. We found that LLLT induced significant increases of CCO concentration (Δ[CCO]) and oxygenated hemoglobin concentration (Δ[HbO]) on the treated site as the laser energy dose accumulated over time. A strong linear interplay between Δ[CCO] and Δ[HbO] was observed for the first time during LLLT, indicating a hemodynamic response of oxygen supply and blood volume closely coupled to the up-regulation of CCO induced by photobiomodulation. These results demonstrate the tremendous potential of broadband NIRS as a non-invasive, in vivo means to study mechanisms of photobiomodulation and perform treatment evaluations of LLLT.

  20. Mesoporous Bamboo Charcoal Nanoparticles as a New Near-Infrared Responsive Drug Carrier for Imaging-Guided Chemotherapy/Photothermal Synergistic Therapy of Tumor.

    PubMed

    Dong, Xinghua; Yin, Wenyan; Yu, Jie; Dou, Ruixia; Bao, Tao; Zhang, Xiao; Yan, Liang; Yong, Yuan; Su, Chunjian; Wang, Qing; Gu, Zhanjun; Zhao, Yuliang

    2016-07-01

    Near-infrared-(NIR)-light-triggered photothermal nanocarriers have attracted much attention for the construction of more smart and effective therapeutic platforms in nanomedicine. Here, a multifunctional drug carrier based on a low cost, natural, and biocompatible material, bamboo charcoal nanoparticles (BCNPs), which are prepared by the pyrolysis of bamboo followed by physical grinding and ultrasonication is reported. The as-prepared BCNPs with porous structure possess not only large surface areas for drug loading but also an efficient photothermal effect, making them become both a suitable drug carrier and photothermal agent for cancer therapy. After loading doxorubicin (DOX) into the BCNPs, the resulting DOX-BCNPs enhance drug potency and more importantly can overcome the drug resistance of DOX in a MCF-7 cancer cell model by significantly increasing cellular uptake while remarkably decreasing drug efflux. The in vivo synergistic effect of combining chemotherapy and photothermal therapy in this drug delivery system is also demonstrated. In addition, the BCNPs enhance optoacoustic imaging contrast due to their high NIR absorbance. Collectively, it is demonstrated that the BCNP drug delivery system constitutes a promising and effective nanocarrier for simultaneous bioimaging and chemo-photothermal synergistic therapy of cancer. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Near-infrared photodetector with reduced dark current

    DOEpatents

    Klem, John F; Kim, Jin K

    2012-10-30

    A photodetector is disclosed for the detection of near-infrared light with a wavelength in the range of about 0.9-1.7 microns. The photodetector, which can be formed as either an nBp device or a pBn device on an InP substrate, includes an InGaAs light-absorbing layer, an InAlGaAs graded layer, an InAlAs or InP barrier layer, and an InGaAs contact layer. The photodetector can detect near-infrared light with or without the use of an applied reverse-bias voltage and is useful as an individual photodetector, or to form a focal plane array.

  2. Comparative clinical study using laser and LED-therapy for orofacial pain relief: dentin hypersensitivity and cervicogenic headache

    NASA Astrophysics Data System (ADS)

    Lizarelli, Rosane F. Z.; Pizzo, Renata C. A.; Florez, Fernando L. E.; Grecco, Clovis; Speciali, Jose G.; Bagnato, Vanderlei S.

    2015-06-01

    Considering several clinical situations, low intensity laser therapy has been widely applied in pain relief or analgesia mechanism. With the advent of new LED-based (light emitting diode) light sources, the need of further clinical experiments aiming to compare the effectiveness among them is paramount. The LED system therapeutic use can be denominated as LEDT - Light Emitting Diode Therapy. This study proposed two clinical evaluations of pain relief effect: to dentin hypersensitivity and to cervicogenic headache using different sources of lasers (low and high intensity) and light emitting diodes (LEDs), one emitting at the spectral band of red (630+/- 5nm) and the other one at infrared band (880+/- 5nm). Two different clinical studies were performed and presented interesting results. Considering dentin hypersensitivity, red and infrared led were so effective than the control group (high intensity laser system); by the other side, considering cervicogenic headache, control group (infrared laser) was the best treatment in comparison to red and infrared led system.

  3. Mechanism of eliciting host immunity against cancer cells treated with silica-phthalocyanine-based near infrared photoimmunotherapy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hisataka

    2016-03-01

    Near infrared (NIR) photoimmunotherapy (PIT) is a new type of molecularly-targeted cancer photo-therapy based on conjugating a near infrared silica-phthalocyanine dye, IR700, to a monoclonal antibody (MAb) targeting cancer-specific cell-surface molecules. When exposed to NIR light, the conjugate induces a highly-selective necrotic/ immunogenic cell death (ICD) only in receptor-positive, MAb-IR700-bound cancer cells. This cell death occurs as early as 1 minute after exposure to NIR light. Meanwhile, immediately adjacent receptor-negative cells including immune cells are unharmed. Therefore, we hypothesized that NIR-PIT could efficiently elicit host immunity against treated cancer cells. Three-dimensional dynamic quantitative phase contrast microscopy and selective plane illumination microscopy of tumor cells undergoing PIT showed rapid swelling in treated cells immediately after light exposure suggesting rapid water influx into cells, followed by irreversible morphologic changes such as bleb formation, and rupture of vesicles. Furthermore, biological markers of ICD including relocation of HSP70/90 and calreticulin, and release of ATP and High Mobility Group Box 1 (HMGB1), were clearly detected immediately after NIR-PIT. When NIR-PIT was performed in a mixture of cancer cells and immature dendritic cells, maturation of immature dendritic cells was strongly induced rapidly after NIR-PIT. In summary, NIR-PIT can induce necrotic/ immunogenic cell death that promotes rapid maturation of immature dendritic cells adjacent to dying cancer cells. Therefore, NIR-PIT could efficiently initiate host immune response against NIR-PIT treated cancer cells growing in patients.

  4. Near-infrared light absorption by brown carbon in the ambient atmosphere

    NASA Astrophysics Data System (ADS)

    Chung, C.; Hoffer, A.; Beres, N. D.; Moosmüller, H.; Liu, C.; Green, M.; Kim, S. W.; Engelbrecht, J. P.; Gelencser, A.

    2017-12-01

    Organic aerosols have been assumed to have little-to-no absorption in the red and near-infrared spectral regions of solar radiation, even though a class of organic aerosols were shown to absorb significantly in these spectral regions. Here, we show that ambient atmospheric data from commonly-used 7-wavelength aethalometers contain evidence of abundant near-infrared light absorption by organic aerosol. This evidence comes from the absorption Ångström exponent over 880 950 nm, which often exceeds values explainable by fresh or coated black carbon, or mineral dust. This evidence is not due to an artifact from the instrument random errors or biases, either. The best explanation for these large 880/950 nm absorption Ångström exponent values in the aethalometer data is near-infrared light absorption by tar balls. Tar balls are among common particles from forest fire.

  5. Theranostic Nanoshells: From Probe Design to Imaging and Treatment of Cancer

    PubMed Central

    Bardhan, Rizia; Lal, Surbhi; Joshi, Amit; Halas, Naomi J.

    2013-01-01

    CONSPECTUS Recent advances in theranostics have expanded our ability to design and construct multifunctional nanoparticles that will ultimately allow us to image and treat diseases in a single clinical procedure. Theranostic nanoparticles, combining targeting, therapeutic and diagnostic functions within a single nanoscale complex, have emerged as a result of this confluence of nanoscience and biomedicine. The theranostic capabilities of gold nanoshells -spherical, silica core, gold shell nanoparticles- have attracted tremendous attention over the past decade as nanoshells have emerged as a promising tool for cancer therapy and bioimaging enhancement. This account examines the design and synthesis of nanoshell-based theranostic agents, their plasmon-derived optical properties and their corresponding applications. Nanoshells illuminated with resonant light are either strong optical absorbers or scatterers, properties which give rise to their unique capabilities. In this account, we discuss the underlying physical principles contributing to the photothermal response of nanoshells. We elucidate the photophysics of nanoshell-induced fluorescence enhancement of weak near-infrared fluorophores. We then describe the application of nanoshells as a contrast agent for optical coherence tomography of breast carcinoma cells in vivo. We also examine the recent progress of nanoshells as a multimodal theranostic probe for near-infrared fluorescence and magnetic resonance imaging (MRI) combined with photothermal ablation of cancer cells. The design and preparation of nanoshell complexes is discussed, and their ability to enhance the photoluminescence of fluorophores while incorporating MR contrast is described. We show the theranostic potential of the multimodal nanoshells in vivo for imaging subcutaneous breast cancer tumors in animal models and their biodistribution in various tissues. We then discuss the potential of nanoshells as light-triggered gene therapy vectors. The plasmonic properties of nanoshells make them highly effective as light controlled delivery vectors, adding temporal control to the spatial control characteristic of nanoparticle-based gene therapy approaches. We describe the fabrication of DNA-conjugated nanoshell complexes and compare the efficiency of light-induced and thermally-induced DNA release of DNA. We examine light-triggered release of DAPI (4',6-diamidino-2-phenylindole) molecules, which bind reversibly to double-stranded DNA, to visualize intracellular light-induced release. Finally, we look at future prospects of nanoshell-based theranostics, the potential impact and near-term challenges of theranostic nanomedicine in the next decade. PMID:21612199

  6. Combined concurrent nanoshell loaded macrophage-mediated photothermal and photodynamic therapies

    NASA Astrophysics Data System (ADS)

    Hirschberg, Henry; Trinidad, Anthony; Christie, Catherine E.; Peng, Qian; Kwon, Young J.; Madsen, Steen

    2015-02-01

    Macrophages loaded with gold nanoshells (AuNS), that convert near infrared light to heat, can be used as transport vectors for photothermal hyperthermia of tumors. The purpose of this study was to investigate the effects of combined macrophage mediated photothermal therapy (PTT) and PDT on head and neck squamous cell carcinoma (HNSCC). The results provide proof of concept for the use of macrophages as a delivery vector of AuNS for photothermal enhancement of the effects of PDT on squamous cell carcinoma. A significant synergy was demonstrated with combined PDT and PTT compared to each modality applied separately.

  7. A Near-Infrared Spectrometer to Measure Zodiacal Light Absorption Spectrum

    NASA Technical Reports Server (NTRS)

    Kutyrev, A. S.; Arendt, R.; Dwek, E.; Kimble, R.; Moseley, S. H.; Rapchun, D.; Silverberg, R. F.

    2010-01-01

    We have developed a high throughput infrared spectrometer for zodiacal light fraunhofer lines measurements. The instrument is based on a cryogenic dual silicon Fabry-Perot etalon which is designed to achieve high signal to noise Fraunhofer line profile measurements. Very large aperture silicon Fabry-Perot etalons and fast camera optics make these measurements possible. The results of the absorption line profile measurements will provide a model free measure of the zodiacal Light intensity in the near infrared. The knowledge of the zodiacal light brightness is crucial for accurate subtraction of zodiacal light foreground for accurate measure of the extragalactic background light after the subtraction of zodiacal light foreground. We present the final design of the instrument and the first results of its performance.

  8. The Nuts and Bolts of Low-level Laser (Light) Therapy

    PubMed Central

    Chung, Hoon; Dai, Tianhong; Sharma, Sulbha K.; Huang, Ying-Ying; Carroll, James D.; Hamblin, Michael R.

    2011-01-01

    Soon after the discovery of lasers in the 1960s it was realized that laser therapy had the potential to improve wound healing and reduce pain, inflammation and swelling. In recent years the field sometimes known as photobiomodulation has broadened to include light-emitting diodes and other light sources, and the range of wavelengths used now includes many in the red and near infrared. The term “low level laser therapy” or LLLT has become widely recognized and implies the existence of the biphasic dose response or the Arndt-Schulz curve. This review will cover the mechanisms of action of LLLT at a cellular and at a tissular level and will summarize the various light sources and principles of dosimetry that are employed in clinical practice. The range of diseases, injuries, and conditions that can be benefited by LLLT will be summarized with an emphasis on those that have reported randomized controlled clinical trials. Serious life-threatening diseases such as stroke, heart attack, spinal cord injury, and traumatic brain injury may soon be amenable to LLLT therapy. PMID:22045511

  9. Colonic Marking With Near-Infrared, Light-Emitting, Diode-Activated Indocyanine Green for Laparoscopic Colorectal Surgery.

    PubMed

    Nagata, Jun; Fukunaga, Yosuke; Akiyoshi, Takashi; Konishi, Tsuyoshi; Fujimoto, Yoshiya; Nagayama, Satoshi; Yamamoto, Noriko; Ueno, Masashi

    2016-02-01

    Accurate identification of the location of colorectal lesions is crucial during laparoscopic surgery. Endoscopic marking has been used as an effective preoperative marker for tumor identification. We investigated the feasibility and safety of an imaging method using near-infrared, light-emitting, diode-activated indocyanine green fluorescence in colorectal laparoscopic surgery. This was a single-institution, prospective study. This study was conducted in a tertiary referral hospital. We enrolled 24 patients who underwent laparoscopic surgery. Indocyanine green and India ink were injected into the same patients undergoing preoperative colonoscopy for colon cancer. During subsequent laparoscopic resection of colorectal tumors, the colon was first observed with white light. Then, indocyanine green was activated with a light-emitting diode at 760 nm as the light source. Near-infrared-induced fluorescence showed tumor location clearly and accurately in all 24 of the patients. All of the patients who underwent laparoscopic surgery after marking had positive indocyanine green staining at the time of surgery. Perioperative complications attributed to dye use were not observed. This study is limited by the cost of indocyanine green detection, the timing of the colonoscopy and tattooing in relation to the operation and identification with indocyanine green, and the small size of the series. These data suggest that our novel method for colonic marking with fluorescence imaging of near-infrared, light-emitting, diode-activated indocyanine green is feasible and safe. This method is useful, has no adverse effects, and can be used for perioperative identification of tumor location. Near-infrared, light-emitting, diode-activated indocyanine green has potential use as a colonic marking agent.

  10. Bone optical spectroscopy for the measurement of hemoglobin content

    NASA Astrophysics Data System (ADS)

    Hollmann, Joseph L.; Arambel, Paula; Piet, Judith; Shefelbine, Sandra; Markovic, Stacey; Niedre, Mark; DiMarzio, Charles A.

    2014-05-01

    Osteoporosis is a common side effect of spinal cord injuries. Blood perfusion in the bone provides an indication of bone health and may help to evaluate therapies addressing bone loss. Current methods for measuring blood perfusion of bone use dyes and ionizing radiation, and yield qualitative results. We present a device capable of measuring blood oxygenation in the tibia. The device illuminates the skin directly over the tibia with a white light source and measures the diffusely reflected light in the near infrared spectrum. Multiple source-detector distances are utilized so that the blood perfusion in skin and bone may be differentiated.

  11. A new near infrared photosensitizing nanoplatform containing blue-emitting up-conversion nanoparticles and hypocrellin A for photodynamic therapy of cancer cells

    NASA Astrophysics Data System (ADS)

    Jin, Shan; Zhou, Liangjun; Gu, Zhanjun; Tian, Gan; Yan, Liang; Ren, Wenlu; Yin, Wenyan; Liu, Xiaodong; Zhang, Xiao; Hu, Zhongbo; Zhao, Yuliang

    2013-11-01

    The utilization of up-conversion nanoparticles (UCNPs) for photodynamic therapy (PDT) has gained significant interest due to their unique ability to convert near infrared light to UV/visible light. Previous work mainly focused on the fabrication of green and red emitting UCNPs to load photosensitizers (PSs) for PDT. In this work, we firstly developed a new multifunctional nanoplatform combining blue-emitting UCNPs with blue-light excited PS (hypocrellin A, HA) as a NIR photosensitizing nanoplatform for PDT of cancer cells. Tween 20 coated NaYbF4:Tm, Gd@NaGdF4 UCNPs (Tween 20-UCNPs) with strong blue up-conversion luminescence and good water dispersibility were prepared for use as PS carriers. The blue emission band matched well with the efficient absorption band of HA, thereby facilitating the resonance energy transfer from UCNPs to HA and then activating HA to produce singlet oxygen (1O2). The in vitro study showed that these Tween 20-UCNPs@HA complexes could efficiently produce 1O2 to kill cancer cells under 980 nm NIR excitation. Moreover, these Gd3+ and Yb3+ containing nanoparticles also exhibited positive contrast effects in both T1 weighted magnetic resonance imaging (MRI) and computed tomography (CT) imaging, making them become a multifunctional platform for simultaneous PDT and bio-imaging.The utilization of up-conversion nanoparticles (UCNPs) for photodynamic therapy (PDT) has gained significant interest due to their unique ability to convert near infrared light to UV/visible light. Previous work mainly focused on the fabrication of green and red emitting UCNPs to load photosensitizers (PSs) for PDT. In this work, we firstly developed a new multifunctional nanoplatform combining blue-emitting UCNPs with blue-light excited PS (hypocrellin A, HA) as a NIR photosensitizing nanoplatform for PDT of cancer cells. Tween 20 coated NaYbF4:Tm, Gd@NaGdF4 UCNPs (Tween 20-UCNPs) with strong blue up-conversion luminescence and good water dispersibility were prepared for use as PS carriers. The blue emission band matched well with the efficient absorption band of HA, thereby facilitating the resonance energy transfer from UCNPs to HA and then activating HA to produce singlet oxygen (1O2). The in vitro study showed that these Tween 20-UCNPs@HA complexes could efficiently produce 1O2 to kill cancer cells under 980 nm NIR excitation. Moreover, these Gd3+ and Yb3+ containing nanoparticles also exhibited positive contrast effects in both T1 weighted magnetic resonance imaging (MRI) and computed tomography (CT) imaging, making them become a multifunctional platform for simultaneous PDT and bio-imaging. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr03515h

  12. Near infrared lasers in flow cytometry.

    PubMed

    Telford, William G

    2015-07-01

    Technology development in flow cytometry has closely tracked laser technology, the light source that flow cytometers almost exclusively use to excite fluorescent probes. The original flow cytometers from the 1970s and 1980s used large water-cooled lasers to produce only one or two laser lines at a time. Modern cytometers can take advantage of the revolution in solid state laser technology to use almost any laser wavelength ranging from the ultraviolet to the near infrared. Commercial cytometers can now be equipped with many small solid state lasers, providing almost any wavelength needed for cellular analysis. Flow cytometers are now equipped to analyze 20 or more fluorescent probes simultaneously, requiring multiple laser wavelengths. Instrument developers are now trying to increase this number by designing fluorescent probes that can be excited by laser wavelength at the "edges" of the visible light range, in the near ultraviolet and near-infrared region. A variety of fluorescent probes have been developed that excite with violet and long wavelength ultraviolet light; however, the near-infrared range (660-800 nm) has yet seen only exploitation in flow cytometry. Fortunately, near-infrared laser diodes and other solid state laser technologies appropriate for flow cytometry have been in existence for some time, and can be readily incorporated into flow cytometers to accelerate fluorescent probe development. The near infrared region represents one of the last "frontiers" to maximize the number of fluorescent probes that can be analyzed by flow cytometry. In addition, near infrared fluorescent probes used in biomedical tracking and imaging could also be employed for flow cytometry with the correct laser wavelengths. This review describes the available technology, including lasers, fluorescent probes and detector technology optimal for near infrared signal detection. Published by Elsevier Inc.

  13. Ligand Enhanced Upconversion of Near-Infrared Photons with Nanocrystal Light Absorbers

    DTIC Science & Technology

    2016-03-04

    www.rsc.org/chemicalscience This journal is © The Royal Society of Cupconversion of near-infrared photons with nanocrystal light absorbers† Zhiyuan...the energy contained in light in order to improve the performance of photovoltaic devices or photocatalysts.1 Reshaping the solar spectrum to match the...optical properties of common semi- conductors will allow the efficient use of all incident light . While many efforts e.g. hot carrier devices,2

  14. Detecting and Segregating Black Tip-Damaged Wheat Kernels Using Visible and Near Infrared Spectroscopy

    USDA-ARS?s Scientific Manuscript database

    Detection of individual wheat kernels with black tip symptom (BTS) and black tip damage (BTD) was demonstrated using near infrared reflectance spectroscopy (NIRS) and silicon light-emitting-diode (LED) based instruments. The two instruments tested, a single kernel near-infrared spectroscopy instrume...

  15. Multi-channel automotive night vision system

    NASA Astrophysics Data System (ADS)

    Lu, Gang; Wang, Li-jun; Zhang, Yi

    2013-09-01

    A four-channel automotive night vision system is designed and developed .It is consist of the four active near-infrared cameras and an Mulit-channel image processing display unit,cameras were placed in the automobile front, left, right and rear of the system .The system uses near-infrared laser light source,the laser light beam is collimated, the light source contains a thermoelectric cooler (TEC),It can be synchronized with the camera focusing, also has an automatic light intensity adjustment, and thus can ensure the image quality. The principle of composition of the system is description in detail,on this basis, beam collimation,the LD driving and LD temperature control of near-infrared laser light source,four-channel image processing display are discussed.The system can be used in driver assistance, car BLIS, car parking assist system and car alarm system in day and night.

  16. Method And Apparatus For Examining A Tissue Using The Spectral Wing Emission Therefrom Induced By Visible To Infrared Photoexcitation.

    DOEpatents

    Alfano, Robert R.; Demos, Stavros G.; Zhang, Gang

    2003-12-16

    Method and an apparatus for examining a tissue using the spectral wing emission therefrom induced by visible to infrared photoexcitation. In one aspect, the method is used to characterize the condition of a tissue sample and comprises the steps of (a) photoexciting the tissue sample with substantially monochromatic light having a wavelength of at least 600 nm; and (b) using the resultant far red and near infrared spectral wing emission (SW) emitted from the tissue sample to characterize the condition of the tissue sample. In one embodiment, the substantially monochromatic photoexciting light is a continuous beam of light, and the resultant steady-state far red and near infrared SW emission from the tissue sample is used to characterize the condition of the tissue sample. In another embodiment, the substantially monochromatic photoexciting light is a light pulse, and the resultant time-resolved far red and near infrared SW emission emitted from the tissue sample is used to characterize the condition of the tissue sample. In still another embodiment, the substantially monochromatic photoexciting light is a polarized light pulse, and the parallel and perpendicular components of the resultant polarized time-resolved SW emission emitted from the tissue sample are used to characterize the condition of the tissue sample.

  17. Cyclodextrin-Based Magnetic Nanoparticles for Cancer Therapy

    PubMed Central

    Jędrzak, Artur; Szutkowski, Kosma; Grześkowiak, Bartosz F.; Markiewicz, Roksana; Jesionowski, Teofil; Jurga, Stefan

    2018-01-01

    Polydopamine (PDA)-coated magnetic nanoparticles functionalized with mono-6-thio-β-cyclodextrin (SH-βCD) were obtained and characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Nuclear and Magnetic Resonance Imaging (NMR and MRI), and doxorubicin (DOXO)-loading experiments. The liver cancer cellular internalization of DOXO-loaded nanoparticles was investigated by confocal imaging microscopy. Synthesized nanomaterials bearing a chemotherapeutic drug and a layer of polydopamine capable of absorbing near-infrared light show high performance in the combined chemo- and photothermal therapy (CT-PTT) of liver cancer due to the synergistic effect of both modalities as demonstrated in vitro. Moreover, our material exhibits improved T2 contrast properties, which have been verified using Carr-Purcell-Meiboom-Gill pulse sequence and MRI Spin-Echo imaging of the nanoparticles dispersed in the agarose gel phantoms. Therefore, the presented results cast new light on the preparation of polydopamine-based magnetic theranostic nanomaterials, as well as on the proper methodology for investigation of magnetic nanoparticles in high field MRI experiments. The prepared material is a robust theranostic nanoasystem with great potential in nanomedicine. PMID:29547559

  18. Evaluation of light detector surface area for functional Near Infrared Spectroscopy.

    PubMed

    Wang, Lei; Ayaz, Hasan; Izzetoglu, Meltem; Onaral, Banu

    2017-10-01

    Functional Near Infrared Spectroscopy (fNIRS) is an emerging neuroimaging technique that utilizes near infrared light to detect cortical concentration changes of oxy-hemoglobin and deoxy-hemoglobin non-invasively. Using light sources and detectors over the scalp, multi-wavelength light intensities are recorded as time series and converted to concentration changes of hemoglobin via modified Beer-Lambert law. Here, we describe a potential source for systematic error in the calculation of hemoglobin changes and light intensity measurements. Previous system characterization and analysis studies looked into various fNIRS parameters such as type of light source, number and selection of wavelengths, distance between light source and detector. In this study, we have analyzed the contribution of light detector surface area to the overall outcome. Results from Monte Carlo based digital phantoms indicated that selection of detector area is a critical system parameter in minimizing the error in concentration calculations. The findings here can guide the design of future fNIRS sensors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Efficiency of photodynamic therapy using indocyanine green and infrared light on MCF-7 breast cancer cells in vitro

    NASA Astrophysics Data System (ADS)

    Ruhi, Mustafa K.; Ak, Ayşe.; Gülsoy, Murat

    2016-03-01

    Cancer is one of the main reasons of death in all around the world. The main treatments of cancer include surgical intervention, radiation therapy and chemotherapy. These treatments can be applied separately or in a combined manner. Another therapeutic method that is still being researched and recently has started to be used in clinical applications is Photodynamic Therapy (PDT). Most photosensitizers currently being investigated are sensitive to red light. However, it is known that infrared light has a better penetration into the skin or tissue. Indocyanine Green (ICG), which is used in this study, is sensitive to infrared light. The aim of this in vitro study is to investigate the effect of PDT on breast cancer cells by using different doses of ICG and infrared light irradiation. 25, 50 and 100 μM ICG concentrations and 25 and 50 J/cm2 laser energy doses were applied to MCF-7 cell lines. MTT analyses were performed on 24, 48 and 72 hours following the treatments. As a result, inhibition of cell viability was observed in a time and dose dependent manner. It can be concluded that ICG-PDT application is a good alternative to conventional radiation therapy and chemotherapy for breast cancer treatment.

  20. Studying infrared light therapy for treating Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Han, Mengmeng; Wang, Qiyan; Zeng, Yuhui; Meng, Qingqiang; Zhang, Jun; Wei, Xunbin

    2016-03-01

    Alzheimer's disease (AD) is an extensive neurodegenerative disease. It is generally believed that there are some connections between AD and amyloid protein plaques in the brain. AD is a chronic disease that usually starts slowly and gets worse over time. The typical symptoms are memory loss, language disorders, mood swings and behavioral issues. Gradual losses of somatic functions eventually lead patients to death. Currently, the main therapeutic method is pharmacotherapy, which may temporarily reduce symptoms, but has many side effects. No current treatment can reverse AD's deterioration. Infrared (IR) light therapy has been studied in a range of single and multiple irradiation protocols in previous studies and was found beneficial for neuropathology. In our research, we have verified the effect of infrared light on AD through Alzheimer's disease mouse model. This transgenic mouse model is made by co-injecting two vectors encoding mutant amyloid precursor protein (APP) and mutant presenilin-1 (PSEN1). We designed an experimental apparatus for treating mice, which primarily includes a therapeutic box and a LED array, which emits infrared light. After the treatment, we assessed the effects of infrared light by testing cognitive performance of the mice in Morris water maze. Our results show that infra-red therapy is able to improve cognitive performance in the mouse model. It might provide a novel and safe way to treat Alzheimer's disease.

  1. Infrared-Transparent Gold Nanoparticles Converted by Tumors to Infrared Absorbers Cure Tumors in Mice by Photothermal Therapy

    PubMed Central

    Hainfeld, James F.; O'Connor, Michael J.; Lin, Ping; Qian, Luping; Slatkin, Daniel N.; Smilowitz, Henry M.

    2014-01-01

    Gold nanoparticles (AuNPs) absorb light and can be used to heat and ablate tumors. The “tissue window” at ∼800 nm (near infrared, NIR) is optimal for best tissue penetration of light. Previously, large, 50–150 nm, gold nanoshells and nanorods that absorb well in the NIR have been used. Small AuNPs that may penetrate tumors better unfortunately barely absorb at 800 nm. We show that small AuNPs conjugated to anti-tumor antibodies are taken up by tumor cells that catalytically aggregate them (by enzyme degradation of antibodies and pH effects), shifting their absorption into the NIR region, thus amplifying their photonic absorption. The AuNPs are NIR transparent until they accumulate in tumor cells, thus reducing background heating in blood and non-targeted cells, increasing specificity, in contrast to constructs that are always NIR-absorptive. Treatment of human squamous cell carcinoma A431 which overexpresses epidermal growth factor receptor (EGFr) in subcutaneous murine xenografts with anti-EGFr antibodies conjugated to 15 nm AuNPs and NIR resulted in complete tumor ablation in most cases with virtually no normal tissue damage. The use of targeted small AuNPs therefore provides a potent new method of selective NIR tumor therapy. PMID:24520385

  2. Near-Infrared Plasmon-Assisted Water Oxidation.

    PubMed

    Nishijima, Yoshiaki; Ueno, Kosei; Kotake, Yuki; Murakoshi, Kei; Inoue, Haruo; Misawa, Hiroaki

    2012-05-17

    We report the stoichiometric evolution of oxygen via water oxidation by irradiating a plasmon-enhanced photocurrent generation system with near-infrared light (λ: 1000 nm), in which gold nanostructures were arrayed on the surface of TiO2 electrode. It is considered that multiple electron holes generated by plasmon-induced charge excitation led to the effective recovery of water oxidation after the electron transfer from gold to TiO2. The proposed system containing a gold nanostructured TiO2 electrode may be a promising artificial photosynthetic system using near-infrared light.

  3. Thermographic and clinical evaluation of 808-nm laser photobiomodulation effects after third molar extraction.

    PubMed

    Pedreira, Amanda A; Wanderley, Flavia G; Sa, Maira F; Viena, Camila S; Perez, Adriano; Hoshi, Ryuichi; Leite, Marcia P; Reis, Silvia R; Medrado, Alena P

    2016-08-01

    A randomized, blind, controlled clinical study was conducted with a convenience sample of 24 patients to evaluate the effectiveness of an aluminum gallium arsenide (AlGaAs) infrared laser 808 nm after third molar extraction by the use of infrared thermography technique. Patients were divided into four groups: erupted third molars were extracted from the patients in Group I and Group II, and impacted third molars were extracted from the patients in Group III and Group IV. Group I and Group III received mock laser therapy in which the device was powered off, and Group II and Group IV were exposed to laser light. Postoperative clinical parameters related to the third molar extraction were evaluated; these parameters included pain, trismus and edema. Circulatory patterns were also evaluated by infrared thermography that exhibited local temperature coefficient at different postoperative periods. A slight improvement was observed for swelling, pain and trismus in patients who received laser irradiation, although the differences were not statistically significant (P>0.05). Laser therapy had a significant influence on the local circulation in the area near the temporomandibular joint, as determined by infrared thermography (P<0.05). Laser therapy was able to change the local circulation, although it did not significantly influence swelling, pain or trismus during the postoperative period.

  4. Differences in visible and near-infrared light reflectance between orange fruit and leaves

    NASA Technical Reports Server (NTRS)

    Gausman, H. W.; Escobar, D. E.; Berumen, A.

    1975-01-01

    The objective was to find the best time during the season (April 26, 1972 to January 8, 1973) to distinguish orange fruit from leaves by spectrophotometrically determining at 10-day intervals when the difference in visible (550- and 650-nm wavelengths) and near-infrared (850-nm wavelength) light reflectance between fruit and nearby leaves was largest. December 5 to January 8 was the best time to distinguish fruit from leaves. During this period the fruit's color was rapidly changing from green to yellow, and the difference in visible light reflectance between fruit and leaves was largest. The difference in near-infrared reflectance between leaves and fruit remained essentially constant during ripening when the difference in visible light reflectance between leaves and fruit was largest.

  5. Near-infrared light controlled photocatalytic activity of carbon quantum dots for highly selective oxidation reaction

    NASA Astrophysics Data System (ADS)

    Li, Haitao; Liu, Ruihua; Lian, Suoyuan; Liu, Yang; Huang, Hui; Kang, Zhenhui

    2013-03-01

    Selective oxidation of alcohols is a fundamental and significant transformation for the large-scale production of fine chemicals, UV and visible light driven photocatalytic systems for alcohol oxidation have been developed, however, the long wavelength near infrared (NIR) and infrared (IR) light have not yet fully utilized by the present photocatalytic systems. Herein, we reported carbon quantum dots (CQDs) can function as an effective near infrared (NIR) light driven photocatalyst for the selective oxidation of benzyl alcohol to benzaldehyde. Based on the NIR light driven photo-induced electron transfer property and its photocatalytic activity for H2O2 decomposition, this metal-free catalyst could realize the transformation from benzyl alcohol to benzaldehyde with high selectivity (100%) and conversion (92%) under NIR light irradiation. HO&z.rad; is the main active oxygen specie in benzyl alcohol selective oxidative reaction confirmed by terephthalic acid photoluminescence probing assay (TA-PL), selecting toluene as the substrate. Such metal-free photocatalytic system also selectively converts other alcohol substrates to their corresponding aldehydes with high conversion, demonstrating a potential application of accessing traditional alcohol oxidation chemistry.Selective oxidation of alcohols is a fundamental and significant transformation for the large-scale production of fine chemicals, UV and visible light driven photocatalytic systems for alcohol oxidation have been developed, however, the long wavelength near infrared (NIR) and infrared (IR) light have not yet fully utilized by the present photocatalytic systems. Herein, we reported carbon quantum dots (CQDs) can function as an effective near infrared (NIR) light driven photocatalyst for the selective oxidation of benzyl alcohol to benzaldehyde. Based on the NIR light driven photo-induced electron transfer property and its photocatalytic activity for H2O2 decomposition, this metal-free catalyst could realize the transformation from benzyl alcohol to benzaldehyde with high selectivity (100%) and conversion (92%) under NIR light irradiation. HO&z.rad; is the main active oxygen specie in benzyl alcohol selective oxidative reaction confirmed by terephthalic acid photoluminescence probing assay (TA-PL), selecting toluene as the substrate. Such metal-free photocatalytic system also selectively converts other alcohol substrates to their corresponding aldehydes with high conversion, demonstrating a potential application of accessing traditional alcohol oxidation chemistry. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00092c

  6. Type Ia Supernova Light Curve Inference: Hierarchical Models for Nearby SN Ia in the Optical and Near Infrared

    NASA Astrophysics Data System (ADS)

    Mandel, Kaisey; Kirshner, R. P.; Narayan, G.; Wood-Vasey, W. M.; Friedman, A. S.; Hicken, M.

    2010-01-01

    I have constructed a comprehensive statistical model for Type Ia supernova light curves spanning optical through near infrared data simultaneously. The near infrared light curves are found to be excellent standard candles (sigma(MH) = 0.11 +/- 0.03 mag) that are less vulnerable to systematic error from dust extinction, a major confounding factor for cosmological studies. A hierarchical statistical framework incorporates coherently multiple sources of randomness and uncertainty, including photometric error, intrinsic supernova light curve variations and correlations, dust extinction and reddening, peculiar velocity dispersion and distances, for probabilistic inference with Type Ia SN light curves. Inferences are drawn from the full probability density over individual supernovae and the SN Ia and dust populations, conditioned on a dataset of SN Ia light curves and redshifts. To compute probabilistic inferences with hierarchical models, I have developed BayeSN, a Markov Chain Monte Carlo algorithm based on Gibbs sampling. This code explores and samples the global probability density of parameters describing individual supernovae and the population. I have applied this hierarchical model to optical and near infrared data of over 100 nearby Type Ia SN from PAIRITEL, the CfA3 sample, and the literature. Using this statistical model, I find that SN with optical and NIR data have a smaller residual scatter in the Hubble diagram than SN with only optical data. The continued study of Type Ia SN in the near infrared will be important for improving their utility as precise and accurate cosmological distance indicators.

  7. Nanotechnology for photodynamic therapy: a perspective from the Laboratory of Dr. Michael R. Hamblin in the Wellman Center for Photomedicine at Massachusetts General Hospital and Harvard Medical School.

    PubMed

    Hamblin, Michael R; Chiang, Long Y; Lakshmanan, Shanmugamurthy; Huang, Ying-Ying; Garcia-Diaz, Maria; Karimi, Mahdi; de Souza Rastelli, Alessandra Nara; Chandran, Rakkiyappan

    2015-08-01

    The research interests of the Hamblin Laboratory are broadly centered on the use of different kinds of light to treat many different diseases. Photodynamic therapy (PDT) uses the combination of dyes with visible light to produce reactive oxygen species and kill bacteria, cancer cells and destroy unwanted tissue. Likewise, UV light is also good at killing especially pathogens. By contrast, red or near-infrared light can have the opposite effect, to act to preserve tissue from dying and can stimulate healing and regeneration. In all these applications, nanotechnology is having an ever-growing impact. In PDT, self-assembled nano-drug carriers (micelles, liposomes, etc.) play a great role in solubilizing the photosensitizers, metal nanoparticles can carry out plasmon resonance enhancement, and fullerenes can act as photosensitizers, themselves. In the realm of healing, single-walled carbon nanotubes can be electrofocused to produce nano-electonic biomedical devices, and nanomaterials will play a great role in restorative dentistry.

  8. Near infrared photoluminescence properties of porous silicon prepared under the influence of light illumination

    NASA Astrophysics Data System (ADS)

    Hamadeh, H.; Naddaf, M.; Jazmati, A.

    2008-12-01

    Porous silicon (PS) has been prepared by anodic etching of boron doped silicon under the influence of monochromatic light illumination. The optical properties of the PS samples have been investigated using temperature dependent photoluminescence (PL) spectroscopy. An overall enhancement of the infrared luminescence yield is caused by the light illumination. In the visible spectral range, changes at the low energy side of the broad PL band were observed. In the near infrared spectral range, a new PL band at 850 nm, which is strongly correlated with light illumination, was detected. The new PL band disappears once blue light is used, whereas an increase in its intensity is observed, when the etching is performed under the illumination of light with wavelengths close to the band gap. By increasing the temperature, the 850 nm transition band grows at the expense of the main near infrared transition at 1100 nm. The recombination characteristics of this PL band are indicative of its extrinsic nature. The macroscopic morphology shows strong dependence on the wavelength of the illumination light. Photoassisted preparation could provide a tool for the control of the optical and structural properties of PS.

  9. The use of near-infrared photography to image fired bullets and cartridge cases.

    PubMed

    Stein, Darrell; Yu, Jorn Chi Chung

    2013-09-01

    An imaging technique that is capable of reducing glare, reflection, and shadows can greatly assist the process of toolmarks comparison. In this work, a camera with near-infrared (near-IR) photographic capabilities was fitted with an IR filter, mounted to a stereomicroscope, and used to capture images of toolmarks on fired bullets and cartridge cases. Fluorescent, white light-emitting diode (LED), and halogen light sources were compared for use with the camera. Test-fired bullets and cartridge cases from different makes and models of firearms were photographed under either near-IR or visible light. With visual comparisons, near-IR images and visible light images were comparable. The use of near-IR photography did not reveal more details and could not effectively eliminate reflections and glare associated with visible light photography. Near-IR photography showed little advantages in manual examination of fired evidence when it was compared with visible light (regular) photography. © 2013 American Academy of Forensic Sciences.

  10. Near infrared spectrum simulation applied to human skin for diagnosis

    NASA Astrophysics Data System (ADS)

    Tsai, Chen-Mu; Fang, Yi-Chin; Wang, Chih-Yu; Chiu, Pin-Chun; Wu, Guo-Ying; Zheng, Wei-Chi; Chemg, Shih-Hao

    2007-11-01

    This research proposes a new method for skin diagnose using near infrared as the light source (750nm~1300nm). Compared to UV and visible light, near infrared might penetrate relatively deep into biological soft tissue in some cases although NIR absorption property of tissue is not a constant for water, fat, and collagen etc. In the research, NIR absorption and scattering properties for skin are discussed firstly using the theory of molecule vibration from Quantum physics and Solid State Physics; secondly the practical model for various NIR absorption spectrum to skin tissue are done by optical simulation for human skin. Finally, experiments are done for further identification of proposed model for human skin and its reaction to near infrared. Results show success with identification from both theory and experiments.

  11. BaTiO3-core Au-shell nanoparticles for photothermal therapy and bimodal imaging.

    PubMed

    Wang, Yanfei; Barhoumi, Aoune; Tong, Rong; Wang, Weiping; Ji, Tianjiao; Deng, Xiaoran; Li, Lele; Lyon, Sophie A; Reznor, Gally; Zurakowski, David; Kohane, Daniel S

    2018-05-01

    We report sub-100 nm metal-shell (Au) dielectric-core (BaTiO 3 ) nanoparticles with bimodal imaging abilities and enhanced photothermal effects. The nanoparticles efficiently absorb light in the near infrared range of the spectrum and convert it to heat to ablate tumors. Their BaTiO 3 core, a highly ordered non-centrosymmetric material, can be imaged by second harmonic generation, and their Au shell generates two-photon luminescence. The intrinsic dual imaging capability allows investigating the distribution of the nanoparticles in relation to the tumor vasculature morphology during photothermal ablation. Our design enabled in vivo real-time tracking of the BT-Au-NPs and observation of their thermally-induced effect on tumor vessels. Photothermal therapy induced by plasmonic nanoparticles has emerged as a promising approach to treating cancer. However, the study of the role of intratumoral nanoparticle distribution in mediating tumoricidal activity has been hampered by the lack of suitable imaging techniques. This work describes metal-shell (Au) dielectric-core (BaTiO 3 ) nanoparticles (abbreviated as BT-Au-NP) for photothermal therapy and bimodal imaging. We demonstrated that sub-100 nm BT-Au-NP can efficiently absorb near infrared light and convert it to heat to ablate tumors. The intrinsic dual imaging capability allowed us to investigate the distribution of the nanoparticles in relation to the tumor vasculature morphology during photothermal ablation, enabling in vivo real-time tracking of the BT-Au-NPs and observation of their thermally-induced effect on tumor vessels. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Spatially selective depleting tumor-associated negative regulatory T-(Treg) cells with near infrared photoimmunotherapy (NIR-PIT): A new cancer immunotherapy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hisataka

    2017-02-01

    Near infrared photoimmunotherapy (NIR-PIT) is a new type of molecularly-targeted photo-therapy based on conjugating a near infrared silica-phthalocyanine dye, IR700, to a monoclonal antibody (MAb) targeting target-specific cell-surface molecules. When exposed to NIR light, the conjugate rapidly induces a highly-selective cell death only in receptor-positive, MAb-IR700-bound cells. Current immunotherapies for cancer seek to modulate the balance among different immune cell populations, thereby promoting anti-tumor immune responses. However, because these are systemic therapies, they often cause treatment-limiting autoimmune adverse effects. It would be ideal to manipulate the balance between suppressor and effector cells within the tumor without disturbing homeostasis elsewhere in the body. CD4+CD25+Foxp3+ regulatory T cells (Tregs) are well-known immune-suppressor cells that play a key role in tumor immuno-evasion and have been the target of systemic immunotherapies. We used CD25-targeted NIR-PIT to selectively deplete Tregs, thus activating CD8+ T and NK cells and restoring local anti-tumor immunity. This not only resulted in regression of the treated tumor but also induced responses in separate untreated tumors of the same cell-line derivation. We conclude that CD25-targeted NIR-PIT causes spatially selective depletion of Tregs, thereby providing an alternative approach to cancer immunotherapy that can treat not only local tumors but also distant metastatic tumors.

  13. Autofluorescence detection and imaging of bladder cancer realized through a cystoscope

    DOEpatents

    Demos, Stavros G [Livermore, CA; deVere White, Ralph W [Sacramento, CA

    2007-08-14

    Near infrared imaging using elastic light scattering and tissue autofluorescence and utilizing interior examination techniques and equipment are explored for medical applications. The approach involves imaging using cross-polarized elastic light scattering and/or tissue autofluorescence in the Near Infra-Red (NIR) coupled with image processing and inter-image operations to differentiate human tissue components.

  14. Near infrared photoimmunotherapy rapidly elicits specific host immunity against cancer cells (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hisataka

    2017-02-01

    Near infrared photoimmunotherapy (NIR-PIT) is a new molecularly-targeted cancer photo-therapy based on conjugating a near infrared silica-phthalocyanine dye, IR700, to a monoclonal antibody (mAb) targeting cell-surface molecules. When exposed to NIR light, the conjugate induces a highly-selective necrotic/immunogenic cell death (ICD) only in target-positive, mAb-IR700-bound cancer cells. This cell death occurs as early as 1 minute after exposure to NIR light. Meanwhile, immediately adjacent target-negative cells are unharmed. Dynamic 3D-microscopy of live tumor cells undergoing NIR-PIT showed rapid swelling in treated cells immediately after light exposure, followed by irreversible morphologic changes such as bleb formation, and rupture of vesicles within several minutes. Furthermore, biological markers of ICD including relocation of HSP70/90 and calreticulin, and release of ATP and High Mobility Group Box 1 (HMGB1), were clearly detected immediately after NIR-PIT. When NIR-PIT was performed in a mixture of cancer cells and immature dendritic cells, maturation of immature dendritic cells was strongly induced rapidly after NIR-PIT. Alternatively, NIR-PIT can also target negative regulatory immune cells such as Treg only in the tumor bed. Treg targeting NIR-PIT against CD25 can deplete >80% of Treg in tumor bed within 20 min that induces activation of tumor cell-specific CD8+-T and NK cells within 1.5 hour, and then these activated cells killed cancer cells in local tumor within 1 day and also in distant tumors of the same cell origin within 2 days. In summary, cancer cell-targeting and immuno-suppressor cell-targeting NIR-PITs effectively induce innate and acquired immunity specifically against cancer cells growing in patients, respectively.

  15. Near-infrared-absorbing gold nanopopcorns with iron oxide cluster core for magnetically amplified photothermal and photodynamic cancer therapy.

    PubMed

    Bhana, Saheel; Lin, Gan; Wang, Lijia; Starring, Hunter; Mishra, Sanjay R; Liu, Gang; Huang, Xiaohua

    2015-06-03

    We present the synthesis and application of a new type of dual magnetic and plasmonic nanostructures for magnetic-field-guided drug delivery and combined photothermal and photodynamic cancer therapy. Near-infrared-absorbing gold nanopopcorns containing a self-assembled iron oxide cluster core were prepared via a seed-mediated growth method. The hybrid nanostructures are superparamagnetic and show great photothermal conversion efficiency (η=61%) under near-infrared irradiation. Compact and stable nanocomplexes for photothermal-photodynamic therapy were formed by coating the nanoparticles with near-infrared-absorbing photosensitizer silicon 2,3-naphthalocyannie dihydroxide and stabilization with poly(ethylene glycol) linked with 11-mercaptoundecanoic acid. The nanocomplex showed enhanced release and cellular uptake of the photosensitizer with the use of a gradient magnetic field. In vitro studies using two different cell lines showed that the dual mode photothermal and photodynamic therapy with the assistance of magnetic-field-guided drug delivery dramatically improved the therapeutic efficacy of cancer cells as compared to the combination treatment without using a magnetic field and the two treatments alone. The "three-in-one" nanocomplex has the potential to carry therapeutic agents deep into a tumor through magnetic manipulation and to completely eradicate tumors by subsequent photothermal and photodynamic therapies without systemic toxicity.

  16. Near-infrared light-controlled tunable grating based on graphene/elastomer composites

    NASA Astrophysics Data System (ADS)

    Wang, Fei; Jia, Shuhai; Wang, Yonglin; Tang, Zhenhua

    2018-02-01

    A near-infrared (nIR) light actuated tunable transmission optical grating based on graphene nanoplatelet (GNP)/polydimethylsiloxane (PDMS) and PDMS is proposed. A simple fabrication protocol is studied that allows integration of the grating with the actuation mechanism; both components are made from soft elastomers, and this ensure the tunability and the light-driven operation of the grating. The resulting grating structure demonstrates continuous period tunability of 2.7% under an actuation power density of 220 mW cm-2 within a period of 3 s and also demonstrates a time-independent characteristic. The proposed infrared activated grating can be developed for wireless remote light splitting in bio/chemical sensing and optical telecommunications applications.

  17. Near-infrared fluorescent probes in cancer imaging and therapy: an emerging field

    PubMed Central

    Yi, Xiaomin; Wang, Fuli; Qin, Weijun; Yang, Xiaojian; Yuan, Jianlin

    2014-01-01

    Near-infrared fluorescence (NIRF) imaging is an attractive modality for early cancer detection with high sensitivity and multi-detection capability. Due to convenient modification by conjugating with moieties of interests, NIRF probes are ideal candidates for cancer targeted imaging. Additionally, the combinatory application of NIRF imaging and other imaging modalities that can delineate anatomical structures extends fluorometric determination of biomedical information. Moreover, nanoparticles loaded with NIRF dyes and anticancer agents contribute to the synergistic management of cancer, which integrates the advantage of imaging and therapeutic functions to achieve the ultimate goal of simultaneous diagnosis and treatment. Appropriate probe design with targeting moieties can retain the original properties of NIRF and pharmacokinetics. In recent years, great efforts have been made to develop new NIRF probes with better photostability and strong fluorescence emission, leading to the discovery of numerous novel NIRF probes with fine photophysical properties. Some of these probes exhibit tumoricidal activities upon light radiation, which holds great promise in photothermal therapy, photodynamic therapy, and photoimmunotherapy. This review aims to provide a timely and concise update on emerging NIRF dyes and multifunctional agents. Their potential uses as agents for cancer specific imaging, lymph node mapping, and therapeutics are included. Recent advances of NIRF dyes in clinical use are also summarized. PMID:24648733

  18. Concept of a selective tumour therapy and its evaluation by near-infrared fluorescence imaging and flat-panel volume computed tomography in mice.

    PubMed

    Alves, Frauke; Dullin, Christian; Napp, Joanna; Missbach-Guentner, Jeannine; Jannasch, Katharina; Mathejczyk, Julia; Pardo, Luis A; Stühmer, Walter; Tietze, Lutz-F

    2009-05-01

    Conventional chemotherapy of cancer has its limitations, especially in advanced and disseminated disease and suffers from lack of specificity. This results in a poor therapeutic index and considerable toxicity to normal organs. Therefore, many efforts are made to develop novel therapeutic tools against cancer with the aim of selectively targeting the drug to the tumour site. Drug delivery strategies fundamentally rely on the identification of good-quality biomarkers, allowing unequivocal discrimination between cancer and healthy tissue. At present, antibodies or antibody fragments have clearly proven their value as carrier molecules specific for a tumour-associated molecular marker. This present review draws attention to the use of near-infrared fluorescence (NIRF) imaging to investigate binding specificity and kinetics of carrier molecules such as monoclonal antibodies. In addition, flat-panel volume computed tomography (fpVCT) will be presented to monitor anatomical structures in tumour mouse models over time in a non-invasive manner. Each imaging device sheds light on a different aspect; functional imaging is applied to optimise the dose schedule and the concept of selective tumour therapies, whereas anatomical imaging assesses preclinically the efficacy of novel tumour therapies. Both imaging techniques in combination allow the visualisation of functional information obtained by NIRF imaging within an adequate anatomic framework.

  19. Regional Cerebral Abnormalities Measured by Frequency-Domain Near-Infrared Spectroscopy in Pediatric Patients During Extracorporeal Membrane Oxygenation.

    PubMed

    Tian, Fenghua; Jenks, Christopher; Potter, Donald; Miles, Darryl; Raman, Lakshmi

    Extracorporeal membrane oxygenation (ECMO) is a form of advanced cardiorespiratory support provided to critically ill patients with severe respiratory or cardiovascular failure. While children undergoing ECMO therapy have significant risk for neurological morbidity, currently there is a lack of reliable bedside tool to detect the neurologic events for patients on ECMO. This study assessed the feasibility of frequency-domain near-infrared spectroscopy (NIRS) for detection of intracranial complications during ECMO therapy. The frequency-domain NIRS device measured the absorption coefficient (µa) and reduced scattering coefficient (µs') at six cranial positions from seven pediatric patients (0-16 years) during ECMO support and five healthy controls (2-14 years). Regional abnormalities in both absorption and scattering were identified among ECMO patients. A main finding in this study is that the abnormalities in scattering appear to be associated with lower-than-normal µs' values in regional areas of the brain. Because light scattering originates from the intracellular structures (such as nuclei and mitochondria), a reduction in scattering primarily reflects loss or decreased density of the brain matter. The results from this study indicate a potential to use the frequency-domain NIRS as a safe and complementary technology for detection of intracranial complications during ECMO therapy.

  20. Near-infrared fluorescent probes in cancer imaging and therapy: an emerging field.

    PubMed

    Yi, Xiaomin; Wang, Fuli; Qin, Weijun; Yang, Xiaojian; Yuan, Jianlin

    2014-01-01

    Near-infrared fluorescence (NIRF) imaging is an attractive modality for early cancer detection with high sensitivity and multi-detection capability. Due to convenient modification by conjugating with moieties of interests, NIRF probes are ideal candidates for cancer targeted imaging. Additionally, the combinatory application of NIRF imaging and other imaging modalities that can delineate anatomical structures extends fluorometric determination of biomedical information. Moreover, nanoparticles loaded with NIRF dyes and anticancer agents contribute to the synergistic management of cancer, which integrates the advantage of imaging and therapeutic functions to achieve the ultimate goal of simultaneous diagnosis and treatment. Appropriate probe design with targeting moieties can retain the original properties of NIRF and pharmacokinetics. In recent years, great efforts have been made to develop new NIRF probes with better photostability and strong fluorescence emission, leading to the discovery of numerous novel NIRF probes with fine photophysical properties. Some of these probes exhibit tumoricidal activities upon light radiation, which holds great promise in photothermal therapy, photodynamic therapy, and photoimmunotherapy. This review aims to provide a timely and concise update on emerging NIRF dyes and multifunctional agents. Their potential uses as agents for cancer specific imaging, lymph node mapping, and therapeutics are included. Recent advances of NIRF dyes in clinical use are also summarized.

  1. M13 phage-functionalized single-walled carbon nanotubes as nanoprobes for second near-infrared window fluorescence imaging of targeted tumors.

    PubMed

    Yi, Hyunjung; Ghosh, Debadyuti; Ham, Moon-Ho; Qi, Jifa; Barone, Paul W; Strano, Michael S; Belcher, Angela M

    2012-03-14

    Second near-infrared (NIR) window light (950-1400 nm) is attractive for in vivo fluorescence imaging due to its deep penetration depth in tissues and low tissue autofluorescence. Here we show genetically engineered multifunctional M13 phage can assemble fluorescent single-walled carbon nanotubes (SWNTs) and ligands for targeted fluorescence imaging of tumors. M13-SWNT probe is detectable in deep tissues even at a low dosage of 2 μg/mL and up to 2.5 cm in tissue-like phantoms. Moreover, targeted probes show specific and up to 4-fold improved uptake in prostate specific membrane antigen positive prostate tumors compared to control nontargeted probes. This M13 phage-based second NIR window fluorescence imaging probe has great potential for specific detection and therapy monitoring of hard-to-detect areas. © 2012 American Chemical Society

  2. M13 phage-functionalized single-walled carbon nanotubes as nanoprobes for second near-infrared window fluorescence imaging of targeted tumors

    PubMed Central

    HAM, MOON-HO; QI, JIFA; BARONE, PAUL W.; STRANO, MICHAEL S.; BELCHER, ANGELA M.

    2014-01-01

    Second near-infrared (NIR) window light (950-1,400 nm) is attractive for in vivo fluorescence imaging due to its deep penetration depth in tissues and low tissue autofluorescence. Here we show genetically engineered multifunctional M13 phage can assemble fluorescent single-walled carbon nanotubes (SWNTs) and ligands for targeted fluorescence imaging of tumors. M13-SWNT probe is detectable in deep tissues even at a low dosage of 2 μg/mL and up to 2.5 cm in tissue-like phantoms. Moreover, targeted probes show specific and up to four-fold improved uptake in prostate specific membrane antigen positive prostate tumors compared to control non-targeted probes. This M13 phage-based second NIR window fluorescence imaging probe has great potential for specific detection and therapy monitoring of hard-to-detect areas. PMID:22268625

  3. Immunogenic cancer cell death selectively induced by near infrared photoimmunotherapy initiates host tumor immunity.

    PubMed

    Ogawa, Mikako; Tomita, Yusuke; Nakamura, Yuko; Lee, Min-Jung; Lee, Sunmin; Tomita, Saori; Nagaya, Tadanobu; Sato, Kazuhide; Yamauchi, Toyohiko; Iwai, Hidenao; Kumar, Abhishek; Haystead, Timothy; Shroff, Hari; Choyke, Peter L; Trepel, Jane B; Kobayashi, Hisataka

    2017-02-07

    Immunogenic cell death (ICD) is a form of cell death that activates an adaptive immune response against dead-cell-associated antigens. Cancer cells killed via ICD can elicit antitumor immunity. ICD is efficiently induced by near-infrared photo-immunotherapy (NIR-PIT) that selectively kills target-cells on which antibody-photoabsorber conjugates bind and are activated by NIR light exposure. Advanced live cell microscopies showed that NIR-PIT caused rapid and irreversible damage to the cell membrane function leading to swelling and bursting, releasing intracellular components due to the influx of water into the cell. The process also induces relocation of ICD bio markers including calreticulin, Hsp70 and Hsp90 to the cell surface and the rapid release of immunogenic signals including ATP and HMGB1 followed by maturation of immature dendritic cells. Thus, NIR-PIT is a therapy that kills tumor cells by ICD, eliciting a host immune response against tumor.

  4. Covering the optical spectrum through collective rare-earth doping of NaGdF4 nanoparticles: 806 and 980 nm excitation routes.

    PubMed

    Skripka, A; Marin, R; Benayas, A; Canton, P; Hemmer, E; Vetrone, F

    2017-05-17

    Today, at the frontier of biomedical research, the need has been clearly established for integrating disease detection and therapeutic function in one single theranostic system. Light-emitting nanoparticles are being intensively investigated to fulfil this demand, by continuously developing nanoparticle systems simultaneously emitting in both the UV/visible (light-triggered release and activation of drugs) and the near-infrared (imaging and tracking) spectral regions. In this work, rare-earth (RE) doped nanoparticles (RENPs) were synthesized via a thermal decomposition process and spectroscopically investigated as potential candidates as all-in-one optical imaging, diagnostic and therapeutic agents. These core/shell/shell nanoparticles (NaGdF 4 :Er 3+ ,Ho 3+ ,Yb 3+ /NaGdF 4 :Nd 3+ ,Yb 3+ /NaGdF 4 ) are optically excited by heating-free 806 nm light that, aside from minimizing the local thermal load, also allows to obtain a deeper sub-tissue penetration with respect to the still widely used 980 nm light. Moreover, these water-dispersed nanoplatforms offer interesting assets as triggers/probes for biomedical applications, by virtue of a plethora of emission bands (spanning the 380-1600 nm range). Our results pave the way to use these RENPs for UV/visible-triggered photodynamic therapy/drug release, while simultaneously tracking the nanoparticle biodistribution and monitoring their therapeutic action through the near-infrared signal that overlaps with biological transparency windows.

  5. Mini Review of TiO2 -Based Multifunctional Nanocomposites for Near-Infrared Light-Responsive Phototherapy.

    PubMed

    Wang, Meifang; Hou, Zhiyao; Al Kheraif, Abdulaziz A; Xing, Bengang; Lin, Jun

    2018-06-25

    Phototherapy with the properties of specific spatial/temporal selectivity and minimal invasiveness has been acknowledged as one of the most promising cancer therapy types. Among all the photoactive substance for phototherapy, titanium dioxide (TiO 2 ) nanomaterials are paid more and more attention due to their outstanding photocatalytic properties, prominent biocompatibility, and excellent chemical stability. However, the wide bandgap (3.0-3.2 eV) of TiO 2 limits its absorption only to the ultraviolet (UV) light region. For a long time, UV light-stimulated TiO 2 was applied in the phototherapy researches of tumors located in the skin layer, while it is unsatisfactory for most deep-tissue tumors. Due to the maximum penetration into tissue existing in the near-infrared (NIR) region, how to use NIR light to trigger photochemical reaction of TiO 2 remains a big challenge. In this review, two strategies to develop and construct NIR-triggered TiO 2 -based nanocomposites (NCs) for phototherapy are summarized, and the relevant mechanism and background knowledge of TiO 2 -based phototherapy are also given in order to better understand the application value and current situation of TiO 2 in phototherapy. Finally, the challenges and research directions of TiO 2 in the future clinic phototherapy application are also discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Near-infrared photodynamic inactivation of S. pneumoniae and its interaction with RAW 264.7 macrophages.

    PubMed

    Leite, Ilaiáli S; Geralde, Mariana C; Salina, Ana C G; Medeiros, Alexandra I; Dovigo, Lívia N; Bagnato, Vanderlei S; Inada, Natalia M

    2018-01-01

    Pneumonia is the main cause of children mortality worldwide, and its major treatment obstacle stems from the microorganisms increasing development of resistance to several antibiotics. Photodynamic therapy has been presenting, for the last decades, promising results for some subtypes of cancer and infections. In this work we aimed to develop a safe and efficient in vitro protocol for photodynamic inactivation of Streptococcus pneumoniae, one of the most commonly found bacteria in pneumonia cases, using two near-infrared light sources and indocyanine green, a FDA approved dye. Photodynamic inactivation experiments with bacteria alone allowed to determine the best parameters for microbial inactivation. Cytotoxicity assays with RAW 264.7 macrophages evaluated the safety of the PDI. To determine if the photodynamic inactivation had a positive or negative effect on the natural killing action of macrophages, we selected and tested fewer indocyanine green concentrations and 10 J/cm 2 on macrophage-S. pneumoniae co-cultures. We concluded that ICG has potential as a photosensitizer for near-infrared photodynamic inactivation of S. pneumoniae, producing minimum negative impact on RAW 264.7 macrophages and having a positive interaction with the immune cell's microbicidal action. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Can dendritic cells see light?

    NASA Astrophysics Data System (ADS)

    Chen, Aaron C.-H.; Huang, Ying-Ying; Sharma, Sulbha K.; Hamblin, Michael R.

    2010-02-01

    There are many reports showing that low-level light/laser therapy (LLLT) can enhance wound healing, upregulate cell proliferation and has anti-apoptotic effects by activating intracellular protective genes. In the field of immune response study, it is not known with any certainty whether light/laser is proinflammatory or anti-inflammatory. Increasingly in recent times dendritic cells have been found to play an important role in inflammation and the immunological response. In this study, we try to look at the impact of low level near infrared light (810-nm) on murine bone-marrow derived dendritic cells. Changes in surface markers, including MHC II, CD80 and CD11c and the secretion of interleukins induced by light may provide additional evidence to reveal the mystery of how light affects the maturation of dendritic cells as well how these light-induced mature dendritic cells would affect the activation of adaptive immune response.

  8. Design and validation of a near-infrared fluorescence endoscope for detection of early esophageal malignancy

    NASA Astrophysics Data System (ADS)

    Waterhouse, Dale J.; Joseph, James; Neves, André A.; di Pietro, Massimiliano; Brindle, Kevin M.; Fitzgerald, Rebecca C.; Bohndiek, Sarah E.

    2016-08-01

    Barrett's esophagus is a known precursor lesion to esophageal adenocarcinoma. In these patients, early detection of premalignant disease, known as dysplasia, allows curative minimally invasive endoscopic therapy, but is confounded by a lack of contrast in white light endoscopy. Imaging fluorescently labeled lectins applied topically to the tissue has the potential to more accurately delineate dysplasia, but tissue autofluorescence limits both sensitivity and contrast when operating in the visible region. To overcome this challenge, we synthesized near-infrared (NIR) fluorescent wheat germ agglutinin (WGA-IR800CW) and constructed a clinically translatable bimodal NIR and white light endoscope. Images of NIR and white light with a field of view of 63 deg and an image resolution of 182 μm are coregistered and the honeycomb artifact arising from the fiber bundle is removed. A minimum detectable concentration of 110 nM was determined using a dilution series of WGA-IR800CW. We demonstrated ex vivo that this system can distinguish between gastric and squamous tissue types in mouse stomachs (p=0.0005) and accurately detect WGA-IR800CW fluorescence in human esophageal resections (compared with a gold standard imaging system, rs>0.90). Based on these findings, future work will optimize the bimodal endoscopic system for clinical trials in Barrett's surveillance.

  9. Improvement of pain and disability in elderly patients with degenerative osteoarthritis of the knee treated with narrow-band light therapy.

    PubMed

    Stelian, J; Gil, I; Habot, B; Rosenthal, M; Abramovici, I; Kutok, N; Khahil, A

    1992-01-01

    To evaluate the effects of low-power light therapy on pain and disability in elderly patients with degenerative osteoarthritis of the knee. Partially double-blinded, fully randomized trial comparing red, infrared, and placebo light emitters. Fifty patients with degenerative osteoarthritis of both knees were randomly assigned to three treatment groups: red (15 patients), infrared (18 patients), and placebo (17 patients). Infrared and placebo emitters were double-blinded. Self-applied treatment to both sides of the knee for 15 minutes twice a day for 10 days. Short-Form McGill Pain Questionnaire, Present Pain Intensity, and Visual Analogue Scale for pain and Disability Index Questionnaire for disability were used. We evaluated pain and disability before and on the tenth day of therapy. The period from the end of the treatment until the patient's request to be retreated was summed up 1 year after the trial. Pain and disability before treatment did not show statistically significant differences between the three groups. Pain reduction in the red and infrared groups after the treatment was more than 50% in all scoring methods (P less than 0.05). There was no significant pain improvement in the placebo group. We observed significant functional improvement in red- and infrared-treated groups (p less than 0.05), but not in the placebo group. The period from the end of treatment until the patients required treatment was longer for red and infrared groups than for the placebo group (4.2 +/- 3.0, 6.1 +/- 3.2, and 0.53 +/- 0.62 months, for red, infrared, and placebo, respectively). Low-power light therapy is effective in relieving pain and disability in degenerative osteoarthritis of the knee.

  10. Plasmonic enhancement of cyanine dyes for near-infrared light-triggered photodynamic/photothermal therapy and fluorescent imaging

    NASA Astrophysics Data System (ADS)

    Lu, Mindan; Kang, Ning; Chen, Chuan; Yang, Liuqing; Li, Yang; Hong, Minghui; Luo, Xiangang; Ren, Lei; Wang, Xiumin

    2017-11-01

    Near-infrared (NIR) triggered cyanine dyes have attracted considerable attention in multimodal tumor theranostics. However, NIR cyanine dyes used in tumor treatment often suffer from low fluorescence intensity and weak singlet oxygen generation efficiency, resulting in inadequate diagnostic and therapy efficacy for tumors. It is still a great challenge to improve both the photodynamic therapy (PDT) and fluorescent imaging (FLI) efficacy of cyanine dyes in tumor applications. Herein, a novel multifunctional nanoagent AuNRs@SiO2-IR795 was developed to realize the integrated photothermal/photodynamic therapy (PTT/PDT) and FLI at a very low dosage of IR795 (0.4 μM) based on metal-enhanced fluorescence (MEF) effects. In our design, both the fluorescence intensity and reactive oxygen species of AuNRs@SiO2-IR795 nanocomposites were significantly enhanced up to 51.7 and 6.3 folds compared with free IR795, owing to the localized surface plasmon resonance band of AuNRs overlapping with the absorption or fluorescence emission band of the IR795 dye. Under NIR laser irradiation, the cancer cell inhibition efficiency in vitro with synergetic PDT/PTT was up to 82.3%, compared with 10.3% for free IR795. Moreover, the enhanced fluorescence intensity of our designed nanocomposites was helpful to track their behavior in tumor cells. Therefore, our designed nanoagents highlight the applications of multimodal diagnostics and therapy in tumors based on MEF.

  11. Near-Infrared Fluorescence Imaging Guided Therapy: Molecular Beacon-Based Photosensitizers Triggered by Breast Cancer-Specific mRNA

    DTIC Science & Technology

    2007-05-01

    1989) Specific targeting and toxicity of sulphonated aluminium phthalocyanine photosensitised liposomes directed to cells by monoclonal antibody in...fluorescence emission wavelengths (λabs 825nm; λem 840nm)[1]. Since the native BChl is very unstable and undergoes rapid oxidation to the chlorin state...noticeable dark toxicity in experimental condition, the viability of cells incubated with 2μM of P30C, P30 or r- P30C without light being the same as

  12. Spatially Offset Raman Spectroscopy for Surgical Margin Evaluation During Breast Conserving Therapy

    DTIC Science & Technology

    2011-02-01

    was connected to a 785 nm diode laser (I0785MB0350M, Innovative Photonics Solutions, Monmouth Junction, NJ) which delivered 80 mW of power to the...I0785MB0350M, Innovative Photonics Solutions, Monmouth Junction, New Jersey). The collection fibers deliv- ered light to a near-infrared-optimized...and Tecnology - calibrated tungsten-halogen lamp was used to correct the sys- tem response.29 After wavenumber binning (in 3.5 cm−1 steps given the

  13. NIR-light-induced surface-enhanced Raman scattering for detection and photothermal/photodynamic therapy of cancer cells using methylene blue-embedded gold nanorod@SiO2 nanocomposites

    PubMed Central

    Seo, Sun-Hwa; Kim, Bo-Mi; Joe, Ara; Han, Hyo-Won; Chen, Xiaoyuan; Cheng, Zhen; Jang, Eue-Soon

    2015-01-01

    Methylene blue-loaded gold nanorod@SiO2 (MB-GNR@SiO2) core@shell nanoparticles are synthesized for use in cancer imaging and photothermal/photodynamic dual therapy. For the preparation of GNR@SiO2 nanoparticles, we found that the silica coating rate of hexadecylcetyltrimethylammonium bromide (CTAB)-capped GNRs is much slower than that of PEGylated GNRs due to the densely coated CTAB bilayer. Encapsulated MB molecules have both monomer and dimer forms that result in an increase in the photosensitizing effect through different photochemical pathways. As a consequence of the excellent plasmonic properties of GNRs at near-infrared (NIR) light, the embedded MB molecules showed NIR light-induced SERS performance with a Raman enhancement factor of 3.0 × 1010, which is enough for the detection of a single cancer cell. Moreover, the MB-GNR@SiO2 nanoparticles exhibit a synergistic effect of photodynamic and photothermal therapies of cancer under single-wavelength NIR laser irradiation. PMID:24424205

  14. NIR-light-induced surface-enhanced Raman scattering for detection and photothermal/photodynamic therapy of cancer cells using methylene blue-embedded gold nanorod@SiO2 nanocomposites.

    PubMed

    Seo, Sun-Hwa; Kim, Bo-Mi; Joe, Ara; Han, Hyo-Won; Chen, Xiaoyuan; Cheng, Zhen; Jang, Eue-Soon

    2014-03-01

    Methylene blue-loaded gold nanorod@SiO2 (MB-GNR@SiO2) core@shell nanoparticles are synthesized for use in cancer imaging and photothermal/photodynamic dual therapy. For the preparation of GNR@SiO2 nanoparticles, we found that the silica coating rate of hexadecylcetyltrimethylammonium bromide (CTAB)-capped GNRs is much slower than that of PEGylated GNRs due to the densely coated CTAB bilayer. Encapsulated MB molecules have both monomer and dimer forms that result in an increase in the photosensitizing effect through different photochemical pathways. As a consequence of the excellent plasmonic properties of GNRs at near-infrared (NIR) light, the embedded MB molecules showed NIR light-induced SERS performance with a Raman enhancement factor of 3.0 × 10(10), which is enough for the detection of a single cancer cell. Moreover, the MB-GNR@SiO2 nanoparticles exhibit a synergistic effect of photodynamic and photothermal therapies of cancer under single-wavelength NIR laser irradiation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Gold nanocages for imaging and therapy of prostate cancer cells

    NASA Astrophysics Data System (ADS)

    Sironi, Laura; Avvakumova, Svetlana; Galbiati, Elisabetta; Locarno, Silvia A.; Macchi, Chiara; D'Alfonso, Laura; Ruscica, Massimiliano; Magni, Paolo; Collini, Maddalena; Romeo, Sergio; Chirico, Giuseppe; Prosperi, Davide

    2016-04-01

    Gold nanocages (AuNCs) have been shown to be a useful tool both for imaging and hyperthermia therapy of cancer, thanks to their outstanding optical properties, low toxicity and facile functionalization with targeting molecules, including peptides and antibodies. In particular, hyperthermia is a minimally invasive therapy which takes advantage of the peculiar properties of gold nanoparticles to efficiently convert the absorbed light into heat. Here, we use AuNCs for the selective targeting and imaging of prostate cancer cells. Moreover, we report the hyperthermic effect characterization of the AuNCs both in solution and internalized in cells. Prostate cancer cells were irradiated at different exposure times, with a pulsed near infrared laser, and the cellular viability was evaluated by confocal microscopy.

  16. Clinical evaluation of near-infrared light transillumination in approximal dentin caries detection.

    PubMed

    Ozkan, Gokhan; Guzel, Kadriye Gorkem Ulu

    2017-08-01

    The objective of this clinical study was to compare conventional caries detection techniques, pen-type laser fluorescence device, and near-infrared light transillumination method in approximal dentin caries lesions. The study included 157 patients, aged 12-18, without any cavity in the posterior teeth. Two calibrated examiners carried out the assessments of selected approximal caries sites independently. After the assessments, the unopened sites were excluded and a total of 161 approximal sites were included in the study. When both the examiners arrived at a consensus regarding the presence of dentin caries, the detected lesions were opened with a conical diamond burr, the cavity extent was examined and validated (gold standard). Sensitivity, specificity, negative predictive value, positive predictive value, accuracy, and area under the ROC curve (Az) values among the caries detection methods were calculated. Bitewing radiography and near-infrared (NIR) light transillumination methods showed the highest sensitivity (0.83-0.82) and accuracy (0.82-0.80) among the methods. Visual inspection showed the lowest sensitivity (0.54). Laser fluorescence device and visual inspection showed nearly equal performance. Near-infrared light transillumination can be used as an alternative method to approximal dentin caries detection. Visual inspection and laser fluorescence device alone should not be used for approximal dentin caries.

  17. Improved Treatment of Photothermal Cancer by Coating TiO2 on Porous Silicon.

    PubMed

    Na, Kil Ju; Park, Gye-Choon

    2016-02-01

    In present society, the technology in various field has been sharply developed and advanced. In medical technology, especially, photothermal therapy and photodynamic therapy have had limelight for curing cancers and diseases. The study investigates the photothermal therapy that reduces side effects of existing cancer treatment, is applied to only cancer cells, and dose not harm any other normal cells. The photothermal properties of porous silicon for therapy are analyzed in order to destroy cancer cells that are more weak at heat than normal ones. For improving performance of porous silicon, it also analyzes the properties when irradiating the near infrared by heterologously junction TiO2 and TiO2NW, photocatalysts that are very stable and harmless to the environment and the human body, to porous silicon. Each sample of Si, PSi, TiO2/Psi, and TiO2NW/PSi was irradiated with 808 nm near-IR of 300, 500, and 700 mW/cm2 light intensity, where the maximum heating temperature was 43.8, 61.6, 67.9, and 61.9 degrees C at 300 mW/cm2; 54.1, 64.3, 78.8, and 68.9 degrees C at 500 mW/cm2; and 97.3, 102.8, 102.5, and 95 0C at 700 mW/cm2. The time required to reach the maximum temperature was less than 10 min for every case. The results indicate that TiO2/PSi thin film irradiated with a single near-infrared wavelength of 808 nm, which is known to have the best human permeability, offers the potential of being the most successful photothermal cancer therapy agent. It maximizes the photo-thermal characteristics within the shortest time, and minimizes the adverse effects on the human body.

  18. Highly efficient near-infrared light-emitting diodes by using type-II CdTe/CdSe core/shell quantum dots as a phosphor

    NASA Astrophysics Data System (ADS)

    Shen, Huaibin; Zheng, Ying; Wang, Hongzhe; Xu, Weiwei; Qian, Lei; Yang, Yixing; Titov, Alexandre; Hyvonen, Jake; Li, Lin Song

    2013-11-01

    In this paper, we present an innovative method for the synthesis of CdTe/CdSe type-II core/shell structure quantum dots (QDs) using ‘greener’ chemicals. The PL of CdTe/CdSe type-II core/shell structure QDs ranges from 600 to 820 nm, and the as-synthesized core/shell structures show narrow size distributions and stable and high quantum yields (50-75%). Highly efficient near-infrared light-emitting diodes (LEDs) have been demonstrated by employing the CdTe/CdSe type-II core/shell QDs as emitters. The devices fabricated based on these type-II core/shell QDs show color-saturated near-infrared emission from the QD layers, a low turn-on voltage of 1.55 V, an external quantum efficiency (EQE) of 1.59%, and a current density and maximum radiant emittance of 2.1 × 103 mA cm-2 and 17.7 mW cm-2 at 8 V it is the first report to use type-II core/shell QDs as near-infrared emitters and these results may offer a practicable platform for the realization of near-infrared QD-based light-emitting diodes, night-vision-readable displays, and friend/foe identification system.

  19. Far-red light-mediated programmable anti-cancer gene delivery in cooperation with photodynamic therapy.

    PubMed

    Wang, Jinhui; He, Hua; Xu, Xin; Wang, Xiao; Chen, Yongbing; Yin, Lichen

    2018-07-01

    Effective anti-cancer therapy is hurdled by the complicated extracellular and intracellular barriers, and thus a smart gene vector that can enable programmable gene delivery is highly demanded. Photo-manipulation of gene delivery processes features spatial and temporal precision, while majority of current strategies utilizes short-wavelength UV/visible light with poor tissue penetration or high-power-density near-infrared (NIR) light that would cause undesired heat damage. Herein, an ROS-degradable polycation was designed and co-delivered with a photosensitizer (PS), thus realizing photo-programmable gene delivery using far-red light (661 nm) at low optical power density (down to 5 mW cm -2 ). Thioketal-crosslinked polyethylenimine (TK-PEI) was synthesized to condense p53 gene to form nanocomplexes (NCs), and hyaluronic acid (HA) modified with pheophytin a (Pha) was coated onto NCs to enhance their colloidal stability and enable cancer cell targeting. Short-time (8-min) light irradiation produced non-lethal amount of ROS to disrupt the endosomal membranes and facilitate p53 gene release via degradation of TK-PEI, which collectively enhanced p53 expression levels toward anti-cancer gene therapy. Long-time (30-min) light irradiation at the post-transfection state generated lethal amount of ROS, which cooperatively killed cancer cells to strengthen p53 gene therapy. To the best of our knowledge, this study represents the first example of an "one stone, three birds" approach to realize cooperative anti-cancer gene therapy using low-power-density, long-wavelength visible light as a single stimulus. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. [Evaluation of Sugar Content of Huanghua Pear on Trees by Visible/Near Infrared Spectroscopy].

    PubMed

    Liu, Hui-jun; Ying, Yi-bin

    2015-11-01

    A method of ambient light correction was proposed to evaluate the sugar content of Huanghua pears on tree by visible/near infrared diffuse reflectance spectroscopy (Vis/NIRS). Due to strong interference of ambient light, it was difficult to collect the efficient spectral of pears on tree. In the field, covering the fruits with a bag blocking ambient light can get better results, but the efficiency is fairly low, the instrument corrections of dark and reference spectra may help to reduce the error of the model, however, the interference of the ambient light cannot be eliminated effectively. In order to reduce the effect of ambient light, a shutter was attached to the front of probe. When opening shutter, the spot spectrum were obtained, on which instrument light and ambient light acted at the same time. While closing shutter, background spectra were obtained, on which only ambient light acted, then the ambient light spectra was subtracted from spot spectra. Prediction models were built using data on tree (before and after ambient light correction) and after harvesting by partial least square (PLS). The results of the correlation coefficient (R) are 0.1, 0.69, 0.924; the root mean square error of prediction (SEP) are 0. 89°Brix, 0.42°Brix, 0.27°Brix; ratio of standard deviation (SD) to SEP (RPD) are 0.79, 1.69, 2.58, respectively. The results indicate that, method of background correction used in the experiment can reduce the effect of ambient lighting on spectral acquisition of Huanghua pears in field, efficiently. This method can be used to collect the visible/near infrared spectrum of fruits in field, and may give full play to visible/near-infrared spectroscopy in preharvest management and maturity testing of fruits in the field.

  1. A Near-Infrared Spectrometer Based on Novel Grating Light Modulators

    PubMed Central

    Wei, Wei; Huang, Shanglian; Wang, Ning; Jin, Zhu; Zhang, Jie; Chen, Weimin

    2009-01-01

    A near-infrared spectrometer based on novel MOEMS grating light modulators is proposed. The spectrum detection method that combines a grating light modulator array with a single near-infrared detector has been applied. Firstly, optics theory has been used to analyze the essential principles of the proposed spectroscopic sensor. Secondly, the grating light modulators have been designed and fabricated by micro-machining technology. Finally, the principles of this spectroscopic sensor have been validated and its key parameters have been tested by experiments. The result shows that the spectral resolution is better than 10 nm, the wavelength deviation is less than 1 nm, the deviation of the intensity of peak wavelength is no more than 0.5%, the driving voltage of grating light modulators array device is below 25 V and the response frequency of it is about 5 kHz. With low cost, satisfactory precision, portability and other advantages, the spectrometer should find potential applications in food safety and quality monitoring, pharmaceutical identification and agriculture product quality classification. PMID:22574065

  2. A near-infrared spectrometer based on novel grating light modulators.

    PubMed

    Wei, Wei; Huang, Shanglian; Wang, Ning; Jin, Zhu; Zhang, Jie; Chen, Weimin

    2009-01-01

    A near-infrared spectrometer based on novel MOEMS grating light modulators is proposed. The spectrum detection method that combines a grating light modulator array with a single near-infrared detector has been applied. Firstly, optics theory has been used to analyze the essential principles of the proposed spectroscopic sensor. Secondly, the grating light modulators have been designed and fabricated by micro-machining technology. Finally, the principles of this spectroscopic sensor have been validated and its key parameters have been tested by experiments. The result shows that the spectral resolution is better than 10 nm, the wavelength deviation is less than 1 nm, the deviation of the intensity of peak wavelength is no more than 0.5%, the driving voltage of grating light modulators array device is below 25 V and the response frequency of it is about 5 kHz. With low cost, satisfactory precision, portability and other advantages, the spectrometer should find potential applications in food safety and quality monitoring, pharmaceutical identification and agriculture product quality classification.

  3. Upconversion fiber-optic confocal microscopy under near-infrared pumping.

    PubMed

    Kim, Do-Hyun; Kang, Jin U; Ilev, Ilko K

    2008-03-01

    We present a simple upconversion fiber-optic confocal microscope design using a near-infrared laser for pumping of a rare-earth-doped glass powder. The nonlinear optical frequency conversion process is highly efficient with more than 2% upconversion fluorescence efficiency at a near-infrared pumping wavelength of 1.55 microm. The upconversion confocal design allows the use of conventional Si detectors and 1.55 microm near-infrared pump light. The lateral and axial resolutions of the system were equal to or better than 1.10 and 13.11 microm, respectively.

  4. Broadband near-field mid-infrared spectroscopy and application to phonon resonances in quartz.

    PubMed

    Ishikawa, Michio; Katsura, Makoto; Nakashima, Satoru; Ikemoto, Yuka; Okamura, Hidekazu

    2012-05-07

    Infrared (IR) spectroscopy is a versatile analytical method and nano-scale spatial resolution could be achieved by scattering type near-field optical microscopy (s-SNOM). The spectral bandwidth was, however, limited to approximately 300 cm(-1) with a laser light source. In the present study, the development of a broadband mid-IR near-field spectroscopy with a ceramic light source is demonstrated. A much wider bandwidth (at least 3000 to 1000 cm(-1)) is achieved with a ceramic light source. The experimental data on quartz Si-O phonon resonance bands are well reproduced by theoretical simulations indicating the validity of the present broadband near-field IR spectroscopy.

  5. Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring.

    PubMed

    Avci, Pinar; Gupta, Asheesh; Sadasivam, Magesh; Vecchio, Daniela; Pam, Zeev; Pam, Nadav; Hamblin, Michael R

    2013-03-01

    Low-level laser (light) therapy (LLLT) is a fast-growing technology used to treat a multitude of conditions that require stimulation of healing, relief of pain and inflammation, and restoration of function. Although skin is naturally exposed to light more than any other organ, it still responds well to red and near-infrared wavelengths. The photons are absorbed by mitochondrial chromophores in skin cells. Consequently, electron transport, adenosine triphosphate nitric oxide release, blood flow, reactive oxygen species increase, and diverse signaling pathways are activated. Stem cells can be activated, allowing increased tissue repair and healing. In dermatology, LLLT has beneficial effects on wrinkles, acne scars, hypertrophic scars, and healing of burns. LLLT can reduce UV damage both as a treatment and as a prophylactic measure. In pigmentary disorders such as vitiligo, LLLT can increase pigmentation by stimulating melanocyte proliferation and reduce depigmentation by inhibiting autoimmunity. Inflammatory diseases such as psoriasis and acne can also be managed. The noninvasive nature and almost complete absence of side effects encourage further testing in dermatology.

  6. Near-infrared (NIR) optogenetics using up-conversion system

    NASA Astrophysics Data System (ADS)

    Hososhima, Shoko; Yuasa, Hideya; Ishizuka, Toru; Yawo, Hiromu

    2015-03-01

    Non-invasive remote control technologies designed to manipulate neural functions for a comprehensive and quantitative understanding of the neuronal network in the brain as well as for the therapy of neurological disorders have long been awaited. Recently, it has become possible to optically manipulate the neuronal activity using biological photo-reactive molecules such as channelrhodopsin-2 (ChR2). However, ChR2 and its relatives are mostly reactive to visible light which does not effectively penetrate through biological tissues. In contrast, near-infrared (NIR) light penetrates deep into the tissues because biological systems are almost transparent to light within this so-called `imaging window'. Here we used lanthanide nanoparticles (LNPs), which are composed of rare-earth elements, as luminous bodies to activate channelrhodopsins (ChRs) since they absorb low-energy NIR light to emit high-energy visible light (up-conversion). Neuron-glioma-hybrid ND-7/23 cells were cultured with LNP(NaYF4:Sc/Yb/Er) particles (peak emission, 543 nm) and transfected to express C1V1 (peak absorbance, 539 nm), a chimera of ChR1 and VChR1. The photocurrents were generated in response to NIR laser light (976 nm) to a level comparable to that evoked by a filtered Hg lamp (530-550 nm). NIR light pulses also evoked action potentials in the cultured neurons that expressed C1V1. It is suggested that the green luminescent light emitted from LNPs effectively activated C1V1 to generate the photocurrent. With the optimization of LNPs, acceptor photo-reactive biomolecules and optics, this system could be applied to non-invasively actuate neurons deep in the brain.

  7. A simple infrared-augmented digital photography technique for detection of pupillary abnormalities.

    PubMed

    Shazly, Tarek A; Bonhomme, G R

    2015-03-01

    The purpose of the study was to describe a simple infrared photography technique to aid in the diagnosis and documentation of pupillary abnormalities. An unmodified 12-megapixel "point and shoot" digital camera was used to obtain binocular still photos and videos under different light conditions with near-infrared illuminating frames. The near-infrared light of 850 nm allows the capture of clear pupil images in both dim and bright light conditions. It also allows easy visualization of the pupil despite pigmented irides by augmenting the contrast between the iris and the pupil. The photos and videos obtained illustrated a variety of pupillary abnormalities using the aforementioned technique. This infrared-augmented photography technique supplements medical education, and aids in the more rapid detection, diagnosis, and documentation of a wide spectrum of pupillary abnormalities. Its portability and ease of use with minimal training complements the education of trainees and facilitates the establishment of difficult diagnoses.

  8. The Two-faced Whirlpool Galaxy

    NASA Image and Video Library

    2017-12-08

    NASA image release January 13, 2011 These images by NASA's Hubble Space Telescope show off two dramatically different face-on views of the spiral galaxy M51, dubbed the Whirlpool Galaxy. The image here, taken in visible light, highlights the attributes of a typical spiral galaxy, including graceful, curving arms, pink star-forming regions, and brilliant blue strands of star clusters. In the image above, most of the starlight has been removed, revealing the Whirlpool's skeletal dust structure, as seen in near-infrared light. This new image is the sharpest view of the dense dust in M51. The narrow lanes of dust revealed by Hubble reflect the galaxy's moniker, the Whirlpool Galaxy, as if they were swirling toward the galaxy's core. To map the galaxy's dust structure, researchers collected the galaxy's starlight by combining images taken in visible and near-infrared light. The visible-light image captured only some of the light; the rest was obscured by dust. The near-infrared view, however, revealed more starlight because near-infrared light penetrates dust. The researchers then subtracted the total amount of starlight from both images to see the galaxy's dust structure. The red color in the near-infrared image traces the dust, which is punctuated by hundreds of tiny clumps of stars, each about 65 light-years wide. These stars have never been seen before. The star clusters cannot be seen in visible light because dense dust enshrouds them. The image reveals details as small as 35 light-years across. Astronomers expected to see large dust clouds, ranging from about 100 light-years to more than 300 light-years wide. Instead, most of the dust is tied up in smooth and diffuse dust lanes. An encounter with another galaxy may have prevented giant clouds from forming. Probing a galaxy's dust structure serves as an important diagnostic tool for astronomers, providing invaluable information on how the gas and dust collapse to form stars. Although Hubble is providing incisive views of the internal structure of galaxies such as M51, the planned James Webb Space Telescope (JWST) is expected to produce even crisper images. Researchers constructed the image by combining visible-light exposures from Jan. 18 to 22, 2005, with the Advanced Camera for Surveys (ACS), and near-infrared light pictures taken in December 2005 with the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington, D.C. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook Credit: NASA, ESA, M. Regan and B. Whitmore (STScI), and R. Chandar (University of Toledo)

  9. The Two-faced Whirlpool Galaxy

    NASA Image and Video Library

    2011-01-13

    NASA image release January 13, 2011 These images by NASA's Hubble Space Telescope show off two dramatically different face-on views of the spiral galaxy M51, dubbed the Whirlpool Galaxy. The image above, taken in visible light, highlights the attributes of a typical spiral galaxy, including graceful, curving arms, pink star-forming regions, and brilliant blue strands of star clusters. In the image here, most of the starlight has been removed, revealing the Whirlpool's skeletal dust structure, as seen in near-infrared light. This new image is the sharpest view of the dense dust in M51. The narrow lanes of dust revealed by Hubble reflect the galaxy's moniker, the Whirlpool Galaxy, as if they were swirling toward the galaxy's core. To map the galaxy's dust structure, researchers collected the galaxy's starlight by combining images taken in visible and near-infrared light. The visible-light image captured only some of the light; the rest was obscured by dust. The near-infrared view, however, revealed more starlight because near-infrared light penetrates dust. The researchers then subtracted the total amount of starlight from both images to see the galaxy's dust structure. The red color in the near-infrared image traces the dust, which is punctuated by hundreds of tiny clumps of stars, each about 65 light-years wide. These stars have never been seen before. The star clusters cannot be seen in visible light because dense dust enshrouds them. The image reveals details as small as 35 light-years across. Astronomers expected to see large dust clouds, ranging from about 100 light-years to more than 300 light-years wide. Instead, most of the dust is tied up in smooth and diffuse dust lanes. An encounter with another galaxy may have prevented giant clouds from forming. Probing a galaxy's dust structure serves as an important diagnostic tool for astronomers, providing invaluable information on how the gas and dust collapse to form stars. Although Hubble is providing incisive views of the internal structure of galaxies such as M51, the planned James Webb Space Telescope (JWST) is expected to produce even crisper images. Researchers constructed the image by combining visible-light exposures from Jan. 18 to 22, 2005, with the Advanced Camera for Surveys (ACS), and near-infrared light pictures taken in December 2005 with the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). Credit: NASA, ESA, S. Beckwith (STScI), and the Hubble Heritage Team (STScI/AURA) The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington, D.C. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

  10. Absorption and electrochromic modulation of near-infrared light: realized by tungsten suboxide

    NASA Astrophysics Data System (ADS)

    Li, Guilian; Zhang, Shouhao; Guo, Chongshen; Liu, Shaoqin

    2016-05-01

    In the present study, needle-like tungsten suboxide W18O49 nanocrystals were fabricated as the optical active substance to realize the aim of optical control of near-infrared light. The W18O49 nanocrystals were selected in this regard due to their unique optical performance. As revealed by the powder absorption result, the needle-like W18O49 nanocrystals show strong and wide photoabsorption in the entire near infrared region of 780-2500 nm, from which thin films with the W18O49 nanocrystal coating thus benefits and can strongly shield off almost all near infrared irradiation, whereas transmitting the majority of visible light. To make it more tunable, the W18O49 nanocrystals were finally assembled onto an ITO glass via the layer-by-layer strategy for later electrochromic investigation. The nanostructured architectures of the W18O49 nanocrystal electrochromic films exhibit high contrast, faster switching response, higher coloration efficiencies (150 cm2 C-1 at 650 nm and 255 cm2 C-1 at 1300 nm), better long-term redox switching stability (reversibility of 98% after 500 cycles) and wide electrochromic spectrum coverage of both the visible and infrared regions.In the present study, needle-like tungsten suboxide W18O49 nanocrystals were fabricated as the optical active substance to realize the aim of optical control of near-infrared light. The W18O49 nanocrystals were selected in this regard due to their unique optical performance. As revealed by the powder absorption result, the needle-like W18O49 nanocrystals show strong and wide photoabsorption in the entire near infrared region of 780-2500 nm, from which thin films with the W18O49 nanocrystal coating thus benefits and can strongly shield off almost all near infrared irradiation, whereas transmitting the majority of visible light. To make it more tunable, the W18O49 nanocrystals were finally assembled onto an ITO glass via the layer-by-layer strategy for later electrochromic investigation. The nanostructured architectures of the W18O49 nanocrystal electrochromic films exhibit high contrast, faster switching response, higher coloration efficiencies (150 cm2 C-1 at 650 nm and 255 cm2 C-1 at 1300 nm), better long-term redox switching stability (reversibility of 98% after 500 cycles) and wide electrochromic spectrum coverage of both the visible and infrared regions. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr09147k

  11. Human infrared vision is triggered by two-photon chromophore isomerization

    PubMed Central

    Palczewska, Grazyna; Vinberg, Frans; Stremplewski, Patrycjusz; Bircher, Martin P.; Salom, David; Komar, Katarzyna; Zhang, Jianye; Cascella, Michele; Wojtkowski, Maciej; Kefalov, Vladimir J.; Palczewski, Krzysztof

    2014-01-01

    Vision relies on photoactivation of visual pigments in rod and cone photoreceptor cells of the retina. The human eye structure and the absorption spectra of pigments limit our visual perception of light. Our visual perception is most responsive to stimulating light in the 400- to 720-nm (visible) range. First, we demonstrate by psychophysical experiments that humans can perceive infrared laser emission as visible light. Moreover, we show that mammalian photoreceptors can be directly activated by near infrared light with a sensitivity that paradoxically increases at wavelengths above 900 nm, and display quadratic dependence on laser power, indicating a nonlinear optical process. Biochemical experiments with rhodopsin, cone visual pigments, and a chromophore model compound 11-cis-retinyl-propylamine Schiff base demonstrate the direct isomerization of visual chromophore by a two-photon chromophore isomerization. Indeed, quantum mechanics modeling indicates the feasibility of this mechanism. Together, these findings clearly show that human visual perception of near infrared light occurs by two-photon isomerization of visual pigments. PMID:25453064

  12. Au Nanomatryoshkas as Efficient Near-Infrared Photothermal Transducers for Cancer Treatment: Benchmarking against Nanoshells

    PubMed Central

    2015-01-01

    Au nanoparticles with plasmon resonances in the near-infrared (NIR) region of the spectrum efficiently convert light into heat, a property useful for the photothermal ablation of cancerous tumors subsequent to nanoparticle uptake at the tumor site. A critical aspect of this process is nanoparticle size, which influences both tumor uptake and photothermal efficiency. Here, we report a direct comparative study of ∼90 nm diameter Au nanomatryoshkas (Au/SiO2/Au) and ∼150 nm diameter Au nanoshells for photothermal therapeutic efficacy in highly aggressive triple negative breast cancer (TNBC) tumors in mice. Au nanomatryoshkas are strong light absorbers with 77% absorption efficiency, while the nanoshells are weaker absorbers with only 15% absorption efficiency. After an intravenous injection of Au nanomatryoshkas followed by a single NIR laser dose of 2 W/cm2 for 5 min, 83% of the TNBC tumor-bearing mice appeared healthy and tumor free >60 days later, while only 33% of mice treated with nanoshells survived the same period. The smaller size and larger absorption cross section of Au nanomatryoshkas combine to make this nanoparticle more effective than Au nanoshells for photothermal cancer therapy. PMID:24889266

  13. Near infrared photoimmunotherapy for lung metastases

    PubMed Central

    Sato, Kazuhide; Nagaya, Tadanobu; Mitsunaga, Makoto; Choyke, Peter L.; Kobayashi, Hisataka

    2015-01-01

    Lung metastases are a leading cause of cancer related deaths; nonetheless current treatments are limited. Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of intravenously injected antibodies that target tumors with the toxicity induced by photosensitizers activated by NIR-light. Herein, we demonstrate the efficacy of NIR-PIT in a mouse model of lung metastases. Experiments were conducted with a HER2, luciferase and GFP expressing cell line (3T3/HER2-luc-GFP). An antibody-photosensitizer conjugate (APC) consisting of trastuzumab and a phthalocyanine dye, IRDye-700DX, was synthesized. In vitro NIR-PIT-induced cytotoxicity was light dose dependent. With 3D culture, repeated NIR-PIT could eradicate entire spheroids. In vivo anti-tumor effects of NIR-PIT included significant reductions in both tumor volume (p = 0.0141 vs. APC) and bioluminescence image (BLI) (p = 0.0086 vs. APC) in the flank model, and prolonged survival (p < 0.0001). BLI demonstrated a significant reduction in lung metastases volume (p = 0.0117 vs. APC). Multiple NIR-PIT doses significantly prolonged survival in the lung metastases model (p < 0.0001). These results suggested that NIR-PIT is a potential new therapy for the local control of lung metastases. PMID:26021765

  14. Brown carbon absorption in the red and near-infrared spectral region

    NASA Astrophysics Data System (ADS)

    Hoffer, András; Tóth, Ádám; Pósfai, Mihály; Eddy Chung, Chul; Gelencsér, András

    2017-06-01

    Black carbon (BC) aerosols have often been assumed to be the only light-absorbing carbonaceous particles in the red and near-infrared spectral regions of solar radiation in the atmosphere. Here we report that tar balls (a specific type of organic aerosol particles from biomass burning) do absorb red and near-infrared radiation significantly. Tar balls were produced in a laboratory experiment, and their chemical and optical properties were measured. The absorption of these particles in the range between 470 and 950 nm was measured with an aethalometer, which is widely used to measure atmospheric aerosol absorption. We find that the absorption coefficient of tar balls at 880 nm is more than 10 % of that at 470 nm. The considerable absorption of red and infrared light by tar balls also follows from their relatively low absorption Ångström coefficient (and significant mass absorption coefficient) in the spectral range between 470 and 950 nm. Our results support the previous finding that tar balls may play an important role in global warming. Due to the non-negligible absorption of tar balls in the near-infrared region, the absorption measured in the field at near-infrared wavelengths cannot solely be due to soot particles.

  15. WISE First-Light Image

    NASA Image and Video Library

    2010-01-06

    This infrared snapshot of a region in the constellation Carina near the Milky Way was taken shortly after NASA Wide-field Infrared Survey Explorer ejected its cover. The first-light picture shows thousands of stars and covers an area three times the s

  16. Red/near-infrared light-emitting diode therapy for traumatic brain injury

    NASA Astrophysics Data System (ADS)

    Naeser, Margaret A.; Martin, Paula I.; Ho, Michael D.; Krengel, Maxine H.; Bogdanova, Yelena; Knight, Jeffrey A.; Yee, Megan K.; Zafonte, Ross; Frazier, Judith; Hamblin, Michael R.; Koo, Bang-Bon

    2015-05-01

    This invited paper reviews our research with scalp application of red/near-infrared (NIR) light-emitting diodes (LED) to improve cognition in chronic, traumatic brain injury 1. Application of red/NIR light improves mitochondrial function (especially hypoxic/compromised cells) promoting increased ATP, important for cellular metabolism. Nitric oxide is released locally, increasing regional cerebral blood flow. Eleven chronic, mTBI participants with closed-head injury and cognitive dysfunction received 18 outpatient treatments (MWF, 6 Wks) starting at 10 Mo. to 8 Yr. post-mTBI (MVA, sports-related, IED blast injury). LED therapy is non-invasive, painless, non-thermal (FDA-cleared, non-significant risk device). Each LED cluster head (2.1" diameter, 500mW, 22.2mW/cm2) was applied 10 min (13J/cm2) to 11 scalp placements: midline, from front-to-back hairline; and bilaterally on dorsolateral prefrontal cortex, temporal, and parietal areas. Testing performed pre- and post-LED (+1 Wk, 1 and 2 Mo post- 18th treatment) showed significant linear trend for LED effect over time, on improved executive function and verbal memory. Fewer PTSD symptoms were reported. New studies at VA Boston include TBI patients treated with transcranial LED (26J/cm2); or treated with only intranasal red, 633nm and NIR, 810nm diodes placed into the nostrils (25 min, 6.5mW, 11.4J/cm2). Intranasal LEDs are hypothesized to deliver photons to hippocampus. Results are similar to Naeser et al. (2014). Actigraphy sleep data show increased sleep time (average, +1 Hr/night) post-18th transcranial or intranasal LED treatment. LED treatments may be self-administered at home (Naeser et al., 2011). A shamcontrolled study with Gulf War Illness Veterans is underway.

  17. The PALM-3000 high-order adaptive optics system for Palomar Observatory

    NASA Astrophysics Data System (ADS)

    Bouchez, Antonin H.; Dekany, Richard G.; Angione, John R.; Baranec, Christoph; Britton, Matthew C.; Bui, Khanh; Burruss, Rick S.; Cromer, John L.; Guiwits, Stephen R.; Henning, John R.; Hickey, Jeff; McKenna, Daniel L.; Moore, Anna M.; Roberts, Jennifer E.; Trinh, Thang Q.; Troy, Mitchell; Truong, Tuan N.; Velur, Viswa

    2008-07-01

    Deployed as a multi-user shared facility on the 5.1 meter Hale Telescope at Palomar Observatory, the PALM-3000 highorder upgrade to the successful Palomar Adaptive Optics System will deliver extreme AO correction in the near-infrared, and diffraction-limited images down to visible wavelengths, using both natural and sodium laser guide stars. Wavefront control will be provided by two deformable mirrors, a 3368 active actuator woofer and 349 active actuator tweeter, controlled at up to 3 kHz using an innovative wavefront processor based on a cluster of 17 graphics processing units. A Shack-Hartmann wavefront sensor with selectable pupil sampling will provide high-order wavefront sensing, while an infrared tip/tilt sensor and visible truth wavefront sensor will provide low-order LGS control. Four back-end instruments are planned at first light: the PHARO near-infrared camera/spectrograph, the SWIFT visible light integral field spectrograph, Project 1640, a near-infrared coronagraphic integral field spectrograph, and 888Cam, a high-resolution visible light imager.

  18. Emergence of two near-infrared windows for in vivo and intraoperative SERS.

    PubMed

    Lane, Lucas A; Xue, Ruiyang; Nie, Shuming

    2018-04-06

    Two clear windows in the near-infrared (NIR) spectrum are of considerable current interest for in vivo molecular imaging and spectroscopic detection. The main rationale is that near-infrared light can penetrate biological tissues such as skin and blood more efficiently than visible light because these tissues scatter and absorb less light at longer wavelengths. The first clear window, defined as light wavelengths between 650nm and 950nm, has been shown to be far superior for in vivo and intraoperative optical imaging than visible light. The second clear window, operating in the wavelength range of 1000-1700nm, has been reported to further improve detection sensitivity, spatial resolution, and tissue penetration because tissue photon scattering and background interference are further reduced at longer wavelengths. Here we discuss recent advances in developing biocompatible plasmonic nanoparticles for in vivo and intraoperative surface-enhanced Raman scattering (SERS) in both the first and second NIR windows. In particular, a new class of 'broad-band' plasmonic nanostructures is well suited for surface Raman enhancement across a broad range of wavelengths allowing a direct comparison of detection sensitivity and tissue penetration between the two NIR window. Also, optimized and encoded SERS nanoparticles are generally nontoxic and are much brighter than near-infrared quantum dots (QDs), raising new possibilities for ultrasensitive detection of microscopic tumors and image-guided precision surgery. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Integrated all-optical infrared switchable plasmonic quantum cascade laser.

    PubMed

    Kohoutek, John; Bonakdar, Alireza; Gelfand, Ryan; Dey, Dibyendu; Nia, Iman Hassani; Fathipour, Vala; Memis, Omer Gokalp; Mohseni, Hooman

    2012-05-09

    We report a type of infrared switchable plasmonic quantum cascade laser, in which far field light in the midwave infrared (MWIR, 6.1 μm) is modulated by a near field interaction of light in the telecommunications wavelength (1.55 μm). To achieve this all-optical switch, we used cross-polarized bowtie antennas and a centrally located germanium nanoslab. The bowtie antenna squeezes the short wavelength light into the gap region, where the germanium is placed. The perturbation of refractive index of the germanium due to the free carrier absorption produced by short wavelength light changes the optical response of the antenna and the entire laser intensity at 6.1 μm significantly. This device shows a viable method to modulate the far field of a laser through a near field interaction.

  20. Dielectric magnetic microparticles as photomagnonic cavities: Enhancing the modulation of near-infrared light by spin waves

    NASA Astrophysics Data System (ADS)

    Almpanis, Evangelos

    2018-05-01

    The coupling between spin waves and optical Mie resonances inside a dielectric magnetic spherical particle, which acts simultaneously as a photonic and magnonic (photomagnonic) cavity, is investigated by means of numerical calculations accurate to arbitrary order in the magnetooptical coupling coefficient. Isolated dielectric magnetic particles with diameters of just a few microns support high-Q optical Mie resonances at near-infrared frequencies and localized spin waves, providing an ultrasmall and compact platform in the emerging field of cavity optomagnonics. Our results predict the occurrence of strong interaction effects, beyond the linear-response approximation, which lead to enhanced modulation of near-infrared light by spin waves through multimagnon absorption and emission mechanisms.

  1. Highly sensitive mode mapping of whispering-gallery modes by scanning thermocouple-probe microscopy.

    PubMed

    Klein, Angela E; Schmidt, Carsten; Liebsch, Mattes; Janunts, Norik; Dobynde, Mikhail; Tünnermann, Andreas; Pertsch, Thomas

    2014-03-01

    We propose a method for mapping optical near-fields with the help of a thermocouple scanning-probe microscope tip. As the tip scans the sample surface, its apex is heated by light absorption, generating a thermovoltage. The thermovoltage map represents the intensity distribution of light at the sample surface. The measurement technique has been employed to map optical whispering-gallery modes in fused silica microdisk resonators operating at near-infrared wavelengths. The method could potentially be employed for near-field imaging of a variety of systems in the near-infrared and visible spectral range.

  2. Theranostic nanoshells: from probe design to imaging and treatment of cancer.

    PubMed

    Bardhan, Rizia; Lal, Surbhi; Joshi, Amit; Halas, Naomi J

    2011-10-18

    Recent advances in nanoscience and biomedicine have expanded our ability to design and construct multifunctional nanoparticles that combine targeting, therapeutic, and diagnostic functions within a single nanoscale complex. The theranostic capabilities of gold nanoshells, spherical nanoparticles with silica cores and gold shells, have attracted tremendous attention over the past decade as nanoshells have emerged as a promising tool for cancer therapy and bioimaging enhancement. This Account examines the design and synthesis of nanoshell-based theranostic agents, their plasmon-derived optical properties, and their corresponding applications. We discuss the design and preparation of nanoshell complexes and their ability to enhance the photoluminescence of fluorophores while maintaining their properties as MR contrast agents. In this Account, we discuss the underlying physical principles that contribute to the photothermal response of nanoshells. We then elucidate the photophysical processes that induce nanoshells to enhance the fluorescence of weak near-infrared fluorophores. Nanoshells illuminated with resonant light are either strong optical absorbers or scatterers, properties that give rise to their unique capabilities. These physical processes have been harnessed to visualize and eliminate cancer cells. We describe the application of nanoshells as a contrast agent for optical coherence tomography of breast carcinoma cells in vivo. Our recent studies examine nanoshells as a multimodal theranostic probe, using these nanoparticles for near-infrared fluorescence and magnetic resonance imaging (MRI) and for the photothermal ablation of cancer cells. Multimodal nanoshells show theranostic potential for imaging subcutaneous breast cancer tumors in animal models and the distribution of tumors in various tissues. Nanoshells also show promise as light-triggered gene therapy vectors, adding temporal control to the spatial control characteristic of nanoparticle-based gene therapy approaches. We describe the fabrication of DNA-conjugated nanoshell complexes and compare the efficiency of light-induced and thermally-induced release of DNA. Double-stranded DNA nanoshells also provide a way to deliver small molecules into cells: we describe the delivery and light-triggered release of DAPI (4',6-diamidino-2-phenylindole), a dye molecule used to stain DNA in the nuclei of cells.

  3. Aqueous phase preparation of ultrasmall MoSe2 nanodots for efficient photothermal therapy of cancer cells

    NASA Astrophysics Data System (ADS)

    Yuwen, Lihui; Zhou, Jiajia; Zhang, Yuqian; Zhang, Qi; Shan, Jingyang; Luo, Zhimin; Weng, Lixing; Teng, Zhaogang; Wang, Lianhui

    2016-01-01

    Photothermal therapy (PTT) is a promising cancer treatment with both high effectiveness and fewer side effects. However, an ideal PTT agent not only needs strong absorption of near-infrared (NIR) light and high photothermal conversion efficiency, but also needs good biocompatibility, stability, and small size, which makes the design and preparation of a novel PTT agent a great challenge. In this work, we developed an ultrasonication-assisted liquid exfoliation method for the direct preparation of ultrasmall (2-3 nm) MoSe2 nanodots (NDs) in aqueous solution and demonstrated their superior properties as a PTT agent. The as-prepared MoSe2 NDs have strong absorption of NIR light and high photothermal conversion efficiency of about 46.5%. In vitro cellular experiments demonstrate that MoSe2 NDs have negligible cytotoxicity and can efficiently kill HeLa cells (human cervical cell line) under NIR laser (785 nm) irradiation.Photothermal therapy (PTT) is a promising cancer treatment with both high effectiveness and fewer side effects. However, an ideal PTT agent not only needs strong absorption of near-infrared (NIR) light and high photothermal conversion efficiency, but also needs good biocompatibility, stability, and small size, which makes the design and preparation of a novel PTT agent a great challenge. In this work, we developed an ultrasonication-assisted liquid exfoliation method for the direct preparation of ultrasmall (2-3 nm) MoSe2 nanodots (NDs) in aqueous solution and demonstrated their superior properties as a PTT agent. The as-prepared MoSe2 NDs have strong absorption of NIR light and high photothermal conversion efficiency of about 46.5%. In vitro cellular experiments demonstrate that MoSe2 NDs have negligible cytotoxicity and can efficiently kill HeLa cells (human cervical cell line) under NIR laser (785 nm) irradiation. Electronic supplementary information (ESI) available: Characterization, size distribution and EDS spectrum of MoSe2 NDs, calculation of the extinction coefficient and photothermal conversion efficiency of MoSe2 NDs. See DOI: 10.1039/c5nr08166a

  4. [VISIBLE LIGHT AND HUMAN SKIN (REVIEW)].

    PubMed

    Tsibadze, A; Chikvaidze, E; Katsitadze, A; Kvachadze, I; Tskhvediani, N; Chikviladze, A

    2015-09-01

    Biological effect of a visible light depends on extend of its property to penetrate into the tissues: the greater is a wavelength the more is an effect of a radiation. An impact of a visible light on the skin is evident by wave and quantum effects. Quanta of a visible radiation carry more energy than infrared radiation, although an influence of such radiation on the skin is produced by the light spectrum on the boarder of the ultraviolet and the infrared rays and is manifested by thermal and chemical effects. It is determined that large doses of a visible light (405-436 nm) can cause skin erythema. At this time, the ratio of generation of free radicals in the skin during an exposure to the ultraviolet and the visible light range from 67-33% respectively. Visible rays of 400-500 nm length of wave cause an increase of the concentration of oxygen's active form and mutation of DNA and proteins in the skin. The urticaria in 4-18% of young people induced by photodermatosis is described. As a result of a direct exposure to sunlight photosensitive eczema is more common in elderly. Special place holds a hereditary disease - porphyria, caused by a visible light. In recent years, dermatologists widely use phototherapy. The method uses polychromatic, non-coherent (wavelength of 515-1200 nm) pulsating beam. During phototherapy/light treatment a patient is being exposed to sunlight or bright artificial light. Sources of visible light are lasers, LEDs and fluorescent lamps which have the full range of a visible light. Phototherapy is used in the treatment of acne vulgaris, seasonal affective disorders, depression, psoriasis, eczema and neurodermities. LED of the red and near infrared range also is characterized by the therapeutic effect. They have an ability to influence cromatophores and enhance ATP synthesis in mitochondria. To speed up the healing of wounds and stimulate hair growth light sources of a weak intensity are used. The light of blue-green spectrum is widely used for the treatment of neonatal hyperbilirubinemy. A photodynamic therapy takes a special place. The third generation of the blue (410 nm), yellow (595 nm) and red photosensitors are used. Photodynamic therapy is used in the treatment of cancer as well.

  5. Near-infrared luminescent cubic silicon carbide nanocrystals for in vivo biomarker applications: an ab initio study

    NASA Astrophysics Data System (ADS)

    Somogyi, Bálint; Zólyomi, Viktor; Gali, Adam

    2012-11-01

    Molecule-sized fluorescent emitters are much sought-after to probe biomolecules in living cells. We demonstrate here by time-dependent density functional calculations that the experimentally achievable 1-2 nm sized silicon carbide nanocrystals can emit light in the near-infrared region after introducing appropriate color centers in them. These near-infrared luminescent silicon carbide nanocrystals may act as ideal fluorophores for in vivo bioimaging.

  6. Non-thermal near-infrared exposure photobiomodulates cellular responses to ionizing radiation in human full thickness skin models.

    PubMed

    König, Anke; Zöller, Nadja; Kippenberger, Stefan; Bernd, August; Kaufmann, Roland; Layer, Paul G; Heselich, Anja

    2018-01-01

    Ionizing and near-infrared radiation are both part of the therapeutic spectrum in cancer treatment. During cancer therapy ionizing radiation is typically used for non-invasive reduction of malignant tissue, while near-infrared photobiomodulation is utilized in palliative medical approaches, e.g. for pain reduction or impairment of wound healing. Furthermore, near-infrared is part of the solar wavelength spectrum. A combined exposure of these two irradiation qualities - either intentionally during medical treatment or unintentionally due to solar exposure - is therefore presumable for cancer patients. Several studies in different model organisms and cell cultures show a strong impact of near-infrared pretreatment on ionizing radiation-induced stress response. To investigate the risks of non-thermal near-infrared (NIR) pretreatment in patients, a human in vitro full thickness skin models (FTSM) was evaluated for radiation research. FTSM were pretreated with therapy-relevant doses of NIR followed by X-radiation, and then examined for DNA-double-strand break (DSB) repair, cell proliferation and apoptosis. Double-treated FTSM revealed a clear influence of NIR on X-radiation-induced stress responses in cells in their typical tissue environment. Furthermore, over a 24h time period, double-treated FTSM presented a significant persistence of DSBs, as compared to samples exclusively irradiated by X-rays. In addition, NIR pretreatment inhibited apoptosis induction of integrated fibroblasts, and counteracted the radiation-induced proliferation inhibition of basal keratinocytes. Our work suggests that cancer patients treated with X-rays should be prevented from uncontrolled NIR irradiation. On the other hand, controlled double-treatment could provide an alternative therapy approach, exposing the patient to less radiation. Copyright © 2017. Published by Elsevier B.V.

  7. Near infrared photoimmunotherapy prevents lung cancer metastases in a murine model

    PubMed Central

    Sato, Kazuhide; Nagaya, Tadanobu; Nakamura, Yuko; Harada, Toshiko; Choyke, Peter L.; Kobayashi, Hisataka

    2015-01-01

    Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of intravenously injected antibodies with the acute toxicity induced by photosensitizers after exposure to NIR-light. Herein, we evaluate the efficacy of NIR-PIT in preventing lung metastases in a mouse model. Lung is one of the most common sites for developing metastases, but it also has the deepest tissue light penetration. Thus, lung is the ideal site for treating early metastases by using a light-based strategy. In vitro NIR-PIT cytotoxicity was assessed with dead cell staining, luciferase activity, and a decrease in cytoplasmic GFP fluorescence in 3T3/HER2-luc-GFP cells incubated with an anti-HER2 antibody photosensitizer conjugate. Cell-specific killing was demonstrated in mixed 2D/3D cell cultures of 3T3/HER2-luc-GFP (target) and 3T3-RFP (non-target) cells. In vivo NIR-PIT was performed in the left lung in a mouse model of lung metastases, and the number of metastasis nodules, tumor fluorescence, and luciferase activity were all evaluated. All three evaluations demonstrated that the NIR-PIT-treated lung had significant reductions in metastatic disease (*p < 0.0001, Mann-Whitney U-test) and that NIR-PIT did not damage non-target tumors or normal lung tissue. Thus, NIR-PIT can specifically prevent early metastases and is a promising anti-metastatic therapy. PMID:25992770

  8. All-photonic drying and sintering process via flash white light combined with deep-UV and near-infrared irradiation for highly conductive copper nano-ink

    PubMed Central

    Hwang, Hyun-Jun; Oh, Kyung-Hwan; Kim, Hak-Sung

    2016-01-01

    We developed an ultra-high speed photonic sintering method involving flash white light (FWL) combined with near infrared (NIR) and deep UV light irradiation to produce highly conductive copper nano-ink film. Flash white light irradiation energy and the power of NIR/deep UV were optimized to obtain high conductivity Cu films. Several microscopic and spectroscopic characterization techniques such as scanning electron microscopy (SEM), a x-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy were employed to characterize the Cu nano-films. Optimally sintered Cu nano-ink films produced using a deep UV-assisted flash white light sintering technique had the lowest resistivity (7.62 μΩ·cm), which was only 4.5-fold higher than that of bulk Cu film (1.68 μΩ•cm). PMID:26806215

  9. All-photonic drying and sintering process via flash white light combined with deep-UV and near-infrared irradiation for highly conductive copper nano-ink.

    PubMed

    Hwang, Hyun-Jun; Oh, Kyung-Hwan; Kim, Hak-Sung

    2016-01-25

    We developed an ultra-high speed photonic sintering method involving flash white light (FWL) combined with near infrared (NIR) and deep UV light irradiation to produce highly conductive copper nano-ink film. Flash white light irradiation energy and the power of NIR/deep UV were optimized to obtain high conductivity Cu films. Several microscopic and spectroscopic characterization techniques such as scanning electron microscopy (SEM), a x-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy were employed to characterize the Cu nano-films. Optimally sintered Cu nano-ink films produced using a deep UV-assisted flash white light sintering technique had the lowest resistivity (7.62 μΩ·cm), which was only 4.5-fold higher than that of bulk Cu film (1.68 μΩ•cm).

  10. Implantable wireless powered light emitting diode (LED) for near-infrared photoimmunotherapy: device development and experimental assessment in vitro and in vivo.

    PubMed

    Nakajima, Kohei; Kimura, Toshihiro; Takakura, Hideo; Yoshikawa, Yasuo; Kameda, Atsushi; Shindo, Takayuki; Sato, Kazuhide; Kobayashi, Hisataka; Ogawa, Mikako

    2018-04-13

    The aim of this study was to develop and assess a novel implantable, wireless-powered, light-emitting diode (LED) for near-infrared photoimmunotherapy (NIR-PIT). NIR-PIT is a recently developed cancer therapy that uses NIR light and antibody-photosensitizer conjugates and is able to induce cancer-specific cell death. Due to limited light penetration depth it is currently unable to treat tumors in deep tissues. Use of implanted LED might potentially overcome this limitation. The wireless LED system was able to emit NIR light up to a distance of 20 cm from the transmitter coil by using low magnetic fields as compliant with limits for use in humans. Results indicated that the LED system was able to kill tumor cells in vitro and to suppress tumor growth in implanted tumor-bearing mice. Results indicated that the proposed implantable wireless LED system was able to suppress tumor growth in vivo . These results are encouraging as wireless LED systems such as the one here developed might be a possible solution to treat tumors in deep regions in humans. Further research in this area would be important. An implantable LED system was developed. It consisted of a LED capsule including two LED sources and a receiver coil coupled with an external coil and power source. Wireless power transmission was guaranteed by using electromagnetic induction. The system was tested in vitro by using EGFR-expressing cells and HER2-expressing cells. The system was also tested in vivo in tumor-bearing mice.

  11. Axial diffusion barriers in near-infrared nanopillar LEDs.

    PubMed

    Scofield, Adam C; Lin, Andrew; Haddad, Michael; Huffaker, Diana L

    2014-11-12

    The growth of GaAs/GaAsP axial heterostructures is demonstrated and implemented as diffusion current barriers in nanopillar light-emitting diodes at near-infrared wavelengths. The nanopillar light-emitting diodes utilize an n-GaAs/i-InGaAs/p-GaAs axial heterostructure for current injection. Axial GaAsP segments are inserted into the n- and p-GaAs portions of the nanopillars surrounding the InGaAs emitter region, acting as diffusion barriers to provide enhanced carrier confinement. Detailed characterization of growth of the GaAsP inserts and electronic band-offset measurements are used to effectively implement the GaAsP inserts as diffusion barriers. The implementation of these barriers in nanopillar light-emitting diodes provides a 5-fold increase in output intensity, making this a promising approach to high-efficiency pillar-based emitters in the near-infrared wavelength range.

  12. Light-Actuated Micromechanical Relays for Zero-Power Infrared Detection

    DTIC Science & Technology

    2017-03-01

    Light-Actuated Micromechanical Relays for Zero-Power Infrared Detection Zhenyun Qian, Sungho Kang, Vageeswar Rajaram, Cristian Cassella, Nicol E...near-zero power infrared (IR) detection . Differently from any existing switching element, the proposed LMR relies on a plasmonically-enhanced...chip enabling the monolithic fabrication of multiple LMRs connected together to form a logic topology suitable for the detection of specific

  13. Wavelength, beam size and type dependences of cerebral low-level light therapy: A Monte Carlo study on visible Chinese human

    NASA Astrophysics Data System (ADS)

    Li, Ting; Zhao, Yue; Duan, Meixue; Sun, Yunlong; Li, Kai

    2014-02-01

    Low level light therapy (LLLT) has been clinically utilized for many indications in medicine requiring protection from cell/tissue death, stimulation of healing and repair of injuries, pain reduction, swelling and inflammation. Presently, use of LLLT to treat stroke, traumatic brain injury, and cognitive dysfunction is attracting growing interest. Near-infrared light can penetrate into the brain tissue, allowing noninvasive treatment to be carried out with few treatment-related adverse events. Optimization of LLLT treatment effect is one key issue of the field; however, only a few experimental tests on mice for wavelength selection have been reported. We addressed this issue by low-cost, straightforward and quantitative comparisons on light dosage distribution in Visible Chinese human head with Monte Carlo modeling of light propagation. Optimized selection in wavelength, beam type and size were given based on comparisons among frequently-used setups (i.e., wavelengths: 660 nm, 810 nm, 980 nm; beam type: Gaussian and flat beam; beam diameter: 2 cm, 4 cm, 6cm).This study provided an efficient way to guide optimization of LLLT setup and selection on wavelength, beam type and size for clinical brain LLLT.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Masiero, Joseph R.; Mainzer, A. K.; Nugent, C. R.

    We present revised near-infrared albedo fits of 2835 main-belt asteroids observed by WISE/NEOWISE over the course of its fully cryogenic survey in 2010. These fits are derived from reflected-light near-infrared images taken simultaneously with thermal emission measurements, allowing for more accurate measurements of the near-infrared albedos than is possible for visible albedo measurements. Because our sample requires reflected light measurements, it undersamples small, low-albedo asteroids, as well as those with blue spectral slopes across the wavelengths investigated. We find that the main belt separates into three distinct groups of 6%, 16%, and 40% reflectance at 3.4 μm. Conversely, the 4.6more » μm albedo distribution spans the full range of possible values with no clear grouping. Asteroid families show a narrow distribution of 3.4 μm albedos within each family that map to one of the three observed groupings, with the (221) Eos family being the sole family associated with the 16% reflectance 3.4 μm albedo group. We show that near-infrared albedos derived from simultaneous thermal emission and reflected light measurements are important indicators of asteroid taxonomy and can identify interesting targets for spectroscopic follow-up.« less

  15. In vivo studies of low level laser (light) therapy for traumatic brain injury

    NASA Astrophysics Data System (ADS)

    Xuan, Weijun; Wu, Qiuhe; Huang, Ying-Ying; Ando, Takahiro; Huang, Liyi; Hamblin, Michael R.

    2012-03-01

    Low-level laser (or light) therapy (LLLT) is attracting growing interest to treat both stroke and traumatic brain injury (TBI). The fact that near-infrared light can penetrate into the brain allows non-invasive treatment to be carried out with a low likelihood of treatment-related adverse events. It is proposed that red and NIR light is absorbed by chromophores in the mitochondria of cells leading to changes in gene transcription and upregulation of proteins involved in cell survival, antioxidant production, collagen synthesis, reduction of chronic inflammation and cell migration and proliferation. We developed a mouse model of controlled cortical impact (CCI) TBI and examined the effect of 0, 1, 3, and 14 daily 810-nm CW laser treatments in the CCI model as measured by neurological severity score and wire grip and motion test. 1 laser Tx gave a significant improvement while 3 laser Tx was even better. Surprisingly 14 laser Tx was no better than no treatment. Histological studies at necropsy suggested that the neurodegeneration was reduced at 14 days and that the cortical lesion was repaired by BrdU+ve neural progenitor (stem) cells at 28 days. Transcranial laser therapy is a promising treatment for acute (and chronic TBI) and the lack of side-effects and paucity of alternative treatments encourages early clinical trials.

  16. Low-level light therapy of the eye and brain.

    PubMed

    Rojas, Julio C; Gonzalez-Lima, F

    2011-01-01

    Low-level light therapy (LLLT) using red to near-infrared light energy has gained attention in recent years as a new scientific approach with therapeutic applications in ophthalmology, neurology, and psychiatry. The ongoing therapeutic revolution spearheaded by LLLT is largely propelled by progress in the basic science fields of photobiology and bioenergetics. This paper describes the mechanisms of action of LLLT at the molecular, cellular, and nervous tissue levels. Photoneuromodulation of cytochrome oxidase activity is the most important primary mechanism of action of LLLT. Cytochrome oxidase is the primary photoacceptor of light in the red to near-infrared region of the electromagnetic spectrum. It is also a key mitochondrial enzyme for cellular bioenergetics, especially for nerve cells in the retina and the brain. Evidence shows that LLLT can secondarily enhance neural metabolism by regulating mitochondrial function, intraneuronal signaling systems, and redox states. Current knowledge about LLLT dosimetry relevant for its hormetic effects on nervous tissue, including noninvasive in vivo retinal and transcranial effects, is also presented. Recent research is reviewed that supports LLLT potential benefits in retinal disease, stroke, neurotrauma, neurodegeneration, and memory and mood disorders. Since mitochondrial dysfunction plays a key role in neurodegeneration, LLLT has potential significant applications against retinal and brain damage by counteracting the consequences of mitochondrial failure. Upon transcranial delivery in vivo, LLLT induces brain metabolic and antioxidant beneficial effects, as measured by increases in cytochrome oxidase and superoxide dismutase activities. Increases in cerebral blood flow and cognitive functions induced by LLLT have also been observed in humans. Importantly, LLLT given at energy densities that exert beneficial effects does not induce adverse effects. This highlights the value of LLLT as a novel paradigm to treat visual, neurological, and psychological conditions, and supports that neuronal energy metabolism could constitute a major target for neurotherapeutics of the eye and brain.

  17. Low-level light therapy of the eye and brain

    PubMed Central

    Rojas, Julio C; Gonzalez-Lima, F

    2011-01-01

    Low-level light therapy (LLLT) using red to near-infrared light energy has gained attention in recent years as a new scientific approach with therapeutic applications in ophthalmology, neurology, and psychiatry. The ongoing therapeutic revolution spearheaded by LLLT is largely propelled by progress in the basic science fields of photobiology and bioenergetics. This paper describes the mechanisms of action of LLLT at the molecular, cellular, and nervous tissue levels. Photoneuromodulation of cytochrome oxidase activity is the most important primary mechanism of action of LLLT. Cytochrome oxidase is the primary photoacceptor of light in the red to near-infrared region of the electromagnetic spectrum. It is also a key mitochondrial enzyme for cellular bioenergetics, especially for nerve cells in the retina and the brain. Evidence shows that LLLT can secondarily enhance neural metabolism by regulating mitochondrial function, intraneuronal signaling systems, and redox states. Current knowledge about LLLT dosimetry relevant for its hormetic effects on nervous tissue, including noninvasive in vivo retinal and transcranial effects, is also presented. Recent research is reviewed that supports LLLT potential benefits in retinal disease, stroke, neurotrauma, neurodegeneration, and memory and mood disorders. Since mitochondrial dysfunction plays a key role in neurodegeneration, LLLT has potential significant applications against retinal and brain damage by counteracting the consequences of mitochondrial failure. Upon transcranial delivery in vivo, LLLT induces brain metabolic and antioxidant beneficial effects, as measured by increases in cytochrome oxidase and superoxide dismutase activities. Increases in cerebral blood flow and cognitive functions induced by LLLT have also been observed in humans. Importantly, LLLT given at energy densities that exert beneficial effects does not induce adverse effects. This highlights the value of LLLT as a novel paradigm to treat visual, neurological, and psychological conditions, and supports that neuronal energy metabolism could constitute a major target for neurotherapeutics of the eye and brain. PMID:28539775

  18. Earthshots: Satellite images of environmental change – Lake Urmia, Iran

    USGS Publications Warehouse

    Adamson, Thomas

    2015-01-01

    The lake’s southern basin is shallower than its northern basin, so recent images show the water disappearing from the southern basin first. These Landsat images use the shortwave-infrared, near-infrared, and green wavelengths of light. Because water absorbs infrared light, water (dark blue to black) contrasts with the surrounding land areas. As the water becomes shallower, light is reflected off of the lakebed in shades of light blue. Lighter blue and bright areas immediately surrounding the lake are where the receding shoreline has exposed the lake bottom.

  19. Near-Infrared Scintillation of Liquid Argon

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tilly, Elizabeth; Escobar, Carlos

    2017-01-01

    Liquid argon is well known to scintillate in the vacuum ultraviolet (VUV) range which is inherently difficult to detect. There has been recent evidence to suggest that it also emits near infrared (NIR) light. If this is the case, many large-scale time projection chambers and other similar detectors will be able to maximize light collection while minimizing cost. The goal of this project is to confirm and quantify this NIR emission. In order to accomplish this, an α-source was placed in a volume of highly purified liquid argon and observed using an infrared PMT with a filter excluding light withmore » wavelength <715 nm. Performing a simple counting experiment, there were indications of NIR scintillation. Further analysis is in progress.« less

  20. Near-infrared autofluorescence imaging to detect parathyroid glands in thyroid surgery.

    PubMed

    Ladurner, R; Al Arabi, N; Guendogar, U; Hallfeldt, Kkj; Stepp, H; Gallwas, Jks

    2018-01-01

    Objective To identify and save parathyroid glands during thyroidectomy by displaying their autofluorescence. Methods Autofluorescence imaging was carried out during thyroidectomy with and without central lymph node dissection. After visual recognition by the surgeon, the parathyroid glands and the surrounding tissue were exposed to near-infrared light with a wavelength of 690-770 nm using a modified Karl Storz near infrared/indocyanine green endoscopic system. Parathyroid tissue was expected to show near infrared autofluorescence at 820 nm, captured in the blue channel of the camera. Results We investigated 41 parathyroid glands from 20 patients; 37 glands were identified correctly based on near-infrared autofluorescence. Neither lymph nodes nor thyroid revealed substantial autofluorescence and nor did adipose tissue. Conclusions Parathyroid tissue is characterised by showing autofluorescence in the near-infrared spectrum. This effect can be used to identify and preserve parathyroid glands during thyroidectomy.

  1. 12P-conjugated PEG-modified gold nanorods combined with near-infrared laser for tumor targeting and photothermal therapy.

    PubMed

    Zhan, Tao; Li, Pengfei; Bi, Shan; Dong, Biao; Song, Hongwei; Ren, Hui; Wang, Liping

    2012-09-01

    Gold nanorods have been reported as potential tumor photothermal therapy in vivo and in vitro. However, development of the safe and efficient tumor-targeting gold nanorods for in vivo localized tumor therapy is still a challenge. In our present study, we synthesized the PEG modified gold nanorods and demonstrated its negligible cytotoxicity in vitro. These nanorods also have been demonstrated to efficiently ablate the different kinds of tumor cells in vitro after exposure to the near-infrared laser. When the PEG modified gold nanorods conjugated with the 12P (sequence: TACHQHVRMVRP), this conjugate showed great tumor-targeting and hyperthermia effects on the human liver cancer cell line HepG2 in vitro when coupled with the near-infrared laser treatment. To determine the potential hyperthermia effect of PEG modified gold nanorods or 12P conjugate on tumor cells in vivo, the mice hepatic cancer cells were used to induce the subcutaneous tumor-bearing model in ICR mice. The significant inhibition effects of near-infrared laser mediated PEG modified gold nanorods or 12P conjugate on the tumor growth were observed. These composite results suggest that the 12P-conjugated PEG modified gold nanorods exhibit great biocompatible, particular tumor-targeting and effective photothermal ablation of tumor cells, which warrant the potential therapeutic value of this conjugate for further application in in vivo localized tumor therapy.

  2. Femtosecond synchronism of x-rays and visible/infrared light in an x-ray free-electron laser

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adams, B. W.

    2007-12-15

    A way is proposed to obtain ultrashort pulses of intense infrared/visible light in few-femtosecond synchronism with x-rays from an x-ray free-electron laser (XFEL). It makes use of the recently proposed emittance-slicing technique [Emma et al., Phys. Rev. Lett. 92, 074801 (2004)] to both restrict the duration of self-amplified spontaneous emission (SASE) to a few femtoseconds and to lead to a coherence enhancement of near-infrared transition undulator radiation (CTUR). The x-rays and the near-infrared light originate within the XFEL undulator from the same slice of electrons within a bunch and are therefore perfectly synchronized with each other. An example of realizingmore » the scheme at the Linac Coherent Light Source is presented. A few side issues are explored briefly, such as the magnitude of the velocity term versus the acceleration term in the Lienard-Wiechert fields and the possible use of the CTUR as a diagnostic tool for the SASE process itself.« less

  3. Applications of Light-Responsive Systems for Cancer Theranostics.

    PubMed

    Chen, Hongzhong; Zhao, Yanli

    2018-06-27

    Achieving controlled and targeted delivery of chemotherapeutic drugs and other therapeutic agents to tumor sites is challenging. Among many stimulus strategies, light as a mode of action shows various advantages such as high spatiotemporal selectivity, minimal invasiveness and easy operation. Thus, drug delivery systems (DDSs) have been designed with the incorporation of various functionalities responsive to light as an exogenous stimulus. Early development has focused on guiding chemotherapeutic drugs to designated location, followed by the utilization of UV irradiation for controlled drug release. Because of the disadvantages of UV light such as phototoxicity and limited tissue penetration depth, scientists have moved the research focus onto developing nanoparticle systems responsive to light in the visible region (400-700 nm), aiming to reduce the phototoxicity. In order to enhance the tissue penetration depth, near-infrared light triggered DDSs become increasingly important. In addition, light-based advanced systems for fluorescent and photoacoustic imaging, as well as photodynamic and photothermal therapy have also been reported. Herein, we highlight some of recent developments by applying light-responsive systems in cancer theranostics, including light activated drug release, photodynamic and photothermal therapy, and bioimaging techniques such as fluorescent and photoacoustic imaging. Future prospect of light-mediated cancer treatment is discussed at the end of the review. This Spotlights on Applications article aims to provide up-to-date information about the rapidly developing field of light-based cancer theranostics.

  4. Safety assessment of near infrared light emitting diodes for diffuse optical measurements

    PubMed Central

    Bozkurt, Alper; Onaral, Banu

    2004-01-01

    Background Near infrared (NIR) light has been used widely to monitor important hemodynamic parameters in tissue non-invasively. Pulse oximetry, near infrared spectroscopy, and diffuse optical tomography are examples of such NIR light-based applications. These and other similar applications employ either lasers or light emitting diodes (LED) as the source of the NIR light. Although the hazards of laser sources have been addressed in regulations, the risk of LED sources in such applications is still unknown. Methods Temperature increase of the human skin caused by near infrared LED has been measured by means of in-vivo and in-vitro experiments. Effects of the conducted and radiated heat in the temperature increase have been analyzed separately. Results Elevations in skin temperature up to 10°C have been observed. The effect of radiated heat due to NIR absorption is low – less than 0.5°C – since emitted light power is comparable to the NIR part of sunlight. The conducted heat due to semiconductor junction of the LED can cause temperature increases up to 9°C. It has been shown that adjusting operational parameters by amplitude modulating or time multiplexing the LED decreases the temperature increase of the skin significantly. Conclusion In this study, we demonstrate that the major risk source of the LED in direct contact with skin is the conducted heat of the LED semiconductor junction, which may cause serious skin burns. Adjusting operational parameters by amplitude modulating or time multiplexing the LED can keep the LED within safe temperature ranges. PMID:15035670

  5. Fucoidan-coated CuS nanoparticles for chemo-and photothermal therapy against cancer

    PubMed Central

    Jang, Bian; Moorthy, Madhappan Santha; Manivasagan, Panchanathan; Xu, Li; Song, Kyeongeun; Lee, Kang Dae; Kwak, Minseok; Oh, Junghwan; Jin, Jun-O

    2018-01-01

    In advanced cancer therapy, the combinational therapeutic effect of photothermal therapy (PTT) using near-infrared (NIR) light-responsive nanoparticles (NPs) and anti-cancer drug delivery-mediated chemotherapy has been widely applied. In the present study, using a facile, low-cost, and solution-based method, we developed and synthesized fucoidan, a natural polymer isolated from seaweed that has demonstrated anti-cancer effect, and coated NPs with it as an ideal candidate in chemo-photothermal therapy against cancer cells. Fucoidan-coated copper sulfide nanoparticles (F-CuS) act not only as a nanocarrier to enhance the intracellular delivery of fucoidan but also as a photothermal agent to effectively ablate different cancer cells (e.g., HeLa, A549, and K562), both in vitro and in vivo, with the induction of apoptosis under 808 nm diode laser irradiation. These results point to the potential usage of F-CuS in treating human cancer. PMID:29560098

  6. Phase controlled homodyne infrared near-field microscopy and spectroscopy reveal inhomogeneity within and among individual boron nitride nanotubes.

    PubMed

    Xu, Xiaoji G; Tanur, Adrienne E; Walker, Gilbert C

    2013-04-25

    We propose a practical method to obtain near-field infrared absorption spectra in apertureless near-field scanning optical microscopy (aNSOM) through homodyne detection with a specific choice of reference phase. The underlying mechanism of the method is illustrated by theoretical and numeric models to show its ability to obtain absorptive rather than dispersive profiles in near-field infrared vibrational microscopy. The proposed near-field nanospectroscopic method is applied to obtain infrared spectra from regions of individual multiwall boron nitride nanotubes (BNNTs) in spatial regions smaller than the diffraction limit of the light source. The spectra suggest variations in interwall spacing within the individual tubes probed.

  7. Modulated near-field spectral extraction of broadband mid-infrared signals with a ceramic light source.

    PubMed

    Ishikawa, Michio; Katsura, Makoto; Nakashima, Satoru; Aizawa, Kento; Inoue, Tsutomu; Okamura, Hidekazu; Ikemoto, Yuka

    2011-06-20

    In order to obtain broadband near-field infrared (IR) spectra, a Fourier-transform IR spectrometer (FT-IR) and a ceramic light source were used with a scattering-type scanning near-field optical microscope (s-SNOM). To suppress the background (far-field) scattering, the distance between the scattering probe and the sample was modulated with frequency Ω by a piezo-electric actuator, and the Ω component was extracted from the signal with a lock-in detection. With Ω=30 kHz, a peak-to-peak modulation amplitude of 198 nm, and a probe with smooth surface near the tip, broadband near-field IR spectra could be obtained in the 1200-2500 cm(-1).

  8. Photoswitchable non-fluorescent thermochromic dye-nanoparticle hybrid probes.

    PubMed

    Harrington, Walter N; Haji, Mwafaq R; Galanzha, Ekaterina I; Nedosekin, Dmitry A; Nima, Zeid A; Watanabe, Fumiya; Ghosh, Anindya; Biris, Alexandru S; Zharov, Vladimir P

    2016-11-08

    Photoswitchable fluorescent proteins with controllable light-dark states and spectral shifts in emission in response to light have led to breakthroughs in the study of cell biology. Nevertheless, conventional photoswitching is not applicable for weakly fluorescent proteins and requires UV light with low depth penetration in bio-tissue. Here we introduce a novel concept of photoswitchable hybrid probes consisting of thermochromic dye and absorbing nanoparticles, in which temperature-sensitive light-dark states and spectral shifts in absorption can be switched through controllable photothermal heating of doped nanoparticles. The proof-of-concept is demonstrated through the use of two different types of temperature-sensitive dyes doped with magnetic nanoparticles and reversibly photoswitched by a near-infrared laser. Photoacoustic imaging revealed the high contrast of these probes, which is sufficient for their visualization in cells and deep tissue. Our results suggest that these new photoswitchable multicolour probes can be used for multimodal cellular diagnostics and potentially for magnetic and photothermal therapy.

  9. Photoswitchable non-fluorescent thermochromic dye-nanoparticle hybrid probes

    NASA Astrophysics Data System (ADS)

    Harrington, Walter N.; Haji, Mwafaq R.; Galanzha, Ekaterina I.; Nedosekin, Dmitry A.; Nima, Zeid A.; Watanabe, Fumiya; Ghosh, Anindya; Biris, Alexandru S.; Zharov, Vladimir P.

    2016-11-01

    Photoswitchable fluorescent proteins with controllable light-dark states and spectral shifts in emission in response to light have led to breakthroughs in the study of cell biology. Nevertheless, conventional photoswitching is not applicable for weakly fluorescent proteins and requires UV light with low depth penetration in bio-tissue. Here we introduce a novel concept of photoswitchable hybrid probes consisting of thermochromic dye and absorbing nanoparticles, in which temperature-sensitive light-dark states and spectral shifts in absorption can be switched through controllable photothermal heating of doped nanoparticles. The proof-of-concept is demonstrated through the use of two different types of temperature-sensitive dyes doped with magnetic nanoparticles and reversibly photoswitched by a near-infrared laser. Photoacoustic imaging revealed the high contrast of these probes, which is sufficient for their visualization in cells and deep tissue. Our results suggest that these new photoswitchable multicolour probes can be used for multimodal cellular diagnostics and potentially for magnetic and photothermal therapy.

  10. Large Magellanic Cloud Near-infrared Synoptic Survey. V. Period–Luminosity Relations of Miras

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yuan, Wenlong; Macri, Lucas M.; He, Shiyuan

    We study the near-infrared properties of 690 Mira candidates in the central region of the Large Magellanic Cloud, based on time-series observations at JHK{sub s}. We use densely sampled I -band observations from the OGLE project to generate template light curves in the near-infrared and derive robust mean magnitudes at those wavelengths. We obtain near-infrared Period–Luminosity relations for oxygen-rich Miras with a scatter as low as 0.12 mag at K{sub s}. We study the Period–Luminosity–Color relations and the color excesses of carbon-rich Miras, which show evidence for a substantially different reddening law.

  11. Gratings and Random Reflectors for Near-Infrared PIN Diodes

    NASA Technical Reports Server (NTRS)

    Gunapala, Sarath; Bandara, Sumith; Liu, John; Ting, David

    2007-01-01

    Crossed diffraction gratings and random reflectors have been proposed as means to increase the quantum efficiencies of InGaAs/InP positive/intrinsic/ negative (PIN) diodes designed to operate as near-infrared photodetectors. The proposal is meant especially to apply to focal-plane imaging arrays of such photodetectors to be used for near-infrared imaging. A further increase in quantum efficiency near the short-wavelength limit of the near-infrared spectrum of such a photodetector array could be effected by removing the InP substrate of the array. The use of crossed diffraction gratings and random reflectors as optical devices for increasing the quantum efficiencies of quantum-well infrared photodetectors (QWIPs) was discussed in several prior NASA Tech Briefs articles. While the optical effects of crossed gratings and random reflectors as applied to PIN photodiodes would be similar to those of crossed gratings and random reflectors as applied to QWIPs, the physical mechanisms by which these optical effects would enhance efficiency differ between the PIN-photodiode and QWIP cases: In a QWIP, the multiple-quantum-well layers are typically oriented parallel to the focal plane and therefore perpendicular or nearly perpendicular to the direction of incidence of infrared light. By virtue of the applicable quantum selection rules, light polarized parallel to the focal plane (as normally incident light is) cannot excite charge carriers and, hence, cannot be detected. A pair of crossed gratings or a random reflector scatters normally or nearly normally incident light so that a significant portion of it attains a component of polarization normal to the focal plane and, hence, can excite charge carriers. A pair of crossed gratings or a random reflector on a PIN photodiode would also scatter light into directions away from the perpendicular to the focal plane. However, in this case, the reason for redirecting light away from the perpendicular is to increase the length of the optical path through the detector to increase the probability of absorption of photons and thereby increase the resulting excitation of charge carriers. A pair of crossed gratings or a random reflector according to the proposal would be fabricated as an integral part of photodetector structure on the face opposite the focal plane (see figure). In the presence of crossed gratings, light would make four passes through the device before departing. In the presence of a random reflector, a significant portion of the light would make more than four passes: After each bounce, light would be scattered at a different random angle, and would have a chance to escape only when it was reflected, relative to the normal, at an angle less than the critical angle for total internal reflection. Given the indices of refraction of the photodiode materials, this angle would be about 17 . This amounts to a very narrow cone for escape of trapped light.

  12. ``Smart'' theranostic lanthanide nanoprobes with simultaneous up-conversion fluorescence and tunable T1-T2 magnetic resonance imaging contrast and near-infrared activated photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Das, Gautom Kumar; Vijayaragavan, Vimalan; Xu, Qing Chi; Padmanabhan, Parasuraman; Bhakoo, Kishore K.; Tamil Selvan, Subramanian; Tan, Timothy Thatt Yang

    2014-10-01

    The current work reports a type of ``smart'' lanthanide-based theranostic nanoprobe, NaDyF4:Yb3+/NaGdF4:Yb3+,Er3+, which is able to circumvent the up-converting poisoning effect of Dy3+ ions to give efficient near infrared (980 nm) triggered up-conversion fluorescence, and offers not only excellent dark T2-weighted MR contrast but also tunable bright and T1-weighted MR contrast properties. Due to the efficient up-converted energy transfer from the nanocrystals to chlorin e6 (Ce6) photosensitizers loaded onto the nanocrystals, cytotoxic singlet oxygen was generated and photodynamic therapy was demonstrated. Therefore, the current multifunctional nanocrystals could be potentially useful in various image-guided diagnoses where bright or dark MRI contrast could be selectively tuned to optimize image quality, but also as an efficient and more penetrative near-infrared activated photodynamic therapy agent.The current work reports a type of ``smart'' lanthanide-based theranostic nanoprobe, NaDyF4:Yb3+/NaGdF4:Yb3+,Er3+, which is able to circumvent the up-converting poisoning effect of Dy3+ ions to give efficient near infrared (980 nm) triggered up-conversion fluorescence, and offers not only excellent dark T2-weighted MR contrast but also tunable bright and T1-weighted MR contrast properties. Due to the efficient up-converted energy transfer from the nanocrystals to chlorin e6 (Ce6) photosensitizers loaded onto the nanocrystals, cytotoxic singlet oxygen was generated and photodynamic therapy was demonstrated. Therefore, the current multifunctional nanocrystals could be potentially useful in various image-guided diagnoses where bright or dark MRI contrast could be selectively tuned to optimize image quality, but also as an efficient and more penetrative near-infrared activated photodynamic therapy agent. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr01717j

  13. Tunable broadband near-infrared absorber based on ultrathin phase-change material

    NASA Astrophysics Data System (ADS)

    Hu, Er-Tao; Gu, Tong; Guo, Shuai; Zang, Kai-Yan; Tu, Hua-Tian; Yu, Ke-Han; Wei, Wei; Zheng, Yu-Xiang; Wang, Song-You; Zhang, Rong-Jun; Lee, Young-Pak; Chen, Liang-Yao

    2017-11-01

    In this work, a tunable broadband near-infrared light absorber was designed and fabricated with a simple and lithography free approach by introducing an ultrathin phase-change material Ge2Sb2Te5 (GST) layer into the metal-dielectric multilayered film structure with the structure parameters as that: SiO2 (72.7 nm)/Ge2Sb2Te5 (6.0 nm)/SiO2 (70.2 nm)/Cu (>100.0 nm). The film structure exhibits a modulation depth of ∼72.6% and an extinction ratio of ∼8.8 dB at the wavelength of 1410 nm. The high light absorption (95%) of the proposed film structure at the wavelength of 450 nm in both of the amorphous and crystalline phase of GST, indicates that the intensity of the reflectance in the infrared region can be rapidly tuned by the blue laser pulses. The proposed planar layered film structure with layer thickness as the only controllable parameter and large reflectivity tuning range shows the potential for practical applications in near-infrared light modulation and absorption.

  14. Multi-spectral imaging with infrared sensitive organic light emitting diode

    PubMed Central

    Kim, Do Young; Lai, Tzung-Han; Lee, Jae Woong; Manders, Jesse R.; So, Franky

    2014-01-01

    Commercially available near-infrared (IR) imagers are fabricated by integrating expensive epitaxial grown III-V compound semiconductor sensors with Si-based readout integrated circuits (ROIC) by indium bump bonding which significantly increases the fabrication costs of these image sensors. Furthermore, these typical III-V compound semiconductors are not sensitive to the visible region and thus cannot be used for multi-spectral (visible to near-IR) sensing. Here, a low cost infrared (IR) imaging camera is demonstrated with a commercially available digital single-lens reflex (DSLR) camera and an IR sensitive organic light emitting diode (IR-OLED). With an IR-OLED, IR images at a wavelength of 1.2 µm are directly converted to visible images which are then recorded in a Si-CMOS DSLR camera. This multi-spectral imaging system is capable of capturing images at wavelengths in the near-infrared as well as visible regions. PMID:25091589

  15. Multi-spectral imaging with infrared sensitive organic light emitting diode

    NASA Astrophysics Data System (ADS)

    Kim, Do Young; Lai, Tzung-Han; Lee, Jae Woong; Manders, Jesse R.; So, Franky

    2014-08-01

    Commercially available near-infrared (IR) imagers are fabricated by integrating expensive epitaxial grown III-V compound semiconductor sensors with Si-based readout integrated circuits (ROIC) by indium bump bonding which significantly increases the fabrication costs of these image sensors. Furthermore, these typical III-V compound semiconductors are not sensitive to the visible region and thus cannot be used for multi-spectral (visible to near-IR) sensing. Here, a low cost infrared (IR) imaging camera is demonstrated with a commercially available digital single-lens reflex (DSLR) camera and an IR sensitive organic light emitting diode (IR-OLED). With an IR-OLED, IR images at a wavelength of 1.2 µm are directly converted to visible images which are then recorded in a Si-CMOS DSLR camera. This multi-spectral imaging system is capable of capturing images at wavelengths in the near-infrared as well as visible regions.

  16. The protozoan, Paramecium primaurelia, as a non-sentient model to test laser light irradiation: The effects of an 808nm infrared laser diode on cellular respiration.

    PubMed

    Amaroli, Andrea; Ravera, Silvia; Parker, Steven; Panfoli, Isabella; Benedicenti, Alberico; Benedicenti, Stefano

    2015-07-01

    Photobiomodulation (PBM) has been used in clinical practice for more than 40 years. Unfortunately, conflicting literature has led to the labelling of PBM as a complementary or alternative medicine approach. However, past and ongoing clinical and research studies by reputable investigators have re-established the merits of PBM as a genuine medical therapy, and the technique has, in the last decade, seen an exponential increase in the numbers of clinical instruments available, and their applications. This resurgence has led to a clear need for appropriate experimental models to test the burgeoning laser technology being developed for medical applications. In this context, an ethical model that employs the protozoan, Paramecium primaurelia, is proposed. We studied the possibility of using the measure of oxygen consumption to test PBM by irradiation with an infrared or near-infrared laser. The results show that an 808nm infrared laser diode (1W; 64J/cm²) affects cellular respiration in P. primaurelia, inducing, in the irradiated cells, a significantly (p < 0.05) increased oxygen consumption of about 40%. Our findings indicate that Paramecium can be an excellent tool in biological assays involving infrared and near-infrared PBM, as it combines the advantages of in vivo results with the practicality of in vitro testing. This test represents a fast, inexpensive and straightforward assay, which offers an alternative to both traditional in vivo testing and more expensive mammalian cellular cultures. 2015 FRAME.

  17. Effect of Photobiomodulation on Mesenchymal Stem Cells.

    PubMed

    Fekrazad, Reza; Asefi, Sohrab; Allahdadi, Mahdi; Kalhori, Katayoun A M

    2016-11-01

    The purpose of this study was to review available literature about the effect of photobiomodulation (PBM) on mesenchymal stem cells (MSCs). The effects of coherent and noncoherent light sources such as low-level lasers and light-emitting diodes (LEDs) on cells and tissues, known as PBM, form the basis of photomedicine. This treatment technique effects cell function, proliferation, and migration, and plays an important role in tissue regeneration. Stem cells have been found to be helpful elements in tissue regeneration, and the combination of stem cell therapy and laser therapy appears to positively affect treatment results. An electronic search in PubMed was conducted of publications from the previous 12 years. English language articles related to the subject were found using selected key words. The full texts of potentially suitable articles were assessed according to inclusion and exclusion criteria. After evaluation, 30 articles were deemed relevant according to the inclusion criteria. The energy density of the laser was 0.7-9 J/cm 2 . The power used for visible light was 30-110 mW and that used for infrared light was 50-800 mW. Nearly all studies showed that low-level laser therapy had a positive effect on cell proliferation. Similar outcomes were found for LED; however, some studies suggest that the laser alone is not effective, and should be used as an adjunct tool. PBM has positive effects on MSCs. This review concluded that doses of 0.7-4 J/cm 2 and wavelengths of 600-700 nm are appropriate for light therapy. The results were dependent upon different parameters; therefore, optimization of parameters used in light therapy to obtain favorable results is required to provide more accurate comparison.

  18. IR780 based nanomaterials for cancer imaging and photothermal, photodynamic and combinatorial therapies.

    PubMed

    Alves, Cátia G; Lima-Sousa, Rita; de Melo-Diogo, Duarte; Louro, Ricardo O; Correia, Ilídio J

    2018-05-05

    IR780, a molecule with a strong optical absorption and emission in the near infrared (NIR) region, is receiving an increasing attention from researchers working in the area of cancer treatment and imaging. Upon irradiation with NIR light, IR780 can produce reactive oxygen species as well as increase the body temperature, thus being a promising agent for application in cancer photodynamic and photothermal therapy. However, IR780's poor water solubility, fast clearance, acute toxicity and low tumor uptake may limit its use. To overcome such issues, several types of nanomaterials have been used to encapsulate and deliver IR780 to tumor cells. This mini-review is focused on the application of IR780 based nanostructures for cancer imaging, and photothermal, photodynamic and combinatorial therapies. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Pairing of near-ultraviolet solar cells with electrochromic windows for smart management of the solar spectrum

    NASA Astrophysics Data System (ADS)

    Davy, Nicholas C.; Sezen-Edmonds, Melda; Gao, Jia; Lin, Xin; Liu, Amy; Yao, Nan; Kahn, Antoine; Loo, Yueh-Lin

    2017-08-01

    Current smart window technologies offer dynamic control of the optical transmission of the visible and near-infrared portions of the solar spectrum to reduce lighting, heating and cooling needs in buildings and to improve occupant comfort. Solar cells harvesting near-ultraviolet photons could satisfy the unmet need of powering such smart windows over the same spatial footprint without competing for visible or infrared photons, and without the same aesthetic and design constraints. Here, we report organic single-junction solar cells that selectively harvest near-ultraviolet photons, produce open-circuit voltages eclipsing 1.6 V and exhibit scalability in power generation, with active layers (10 cm2) substantially larger than those typical of demonstration organic solar cells (0.04-0.2 cm2). Integration of these solar cells with a low-cost, polymer-based electrochromic window enables intelligent management of the solar spectrum, with near-ultraviolet photons powering the regulation of visible and near-infrared photons for natural lighting and heating purposes.

  20. NICMOS PEELS AWAY LAYERS OF DUST TO SHOW INNER REGION OF DUSTY NEBULA

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The revived Near Infrared Camera and Multi-Object Spectrometer (NICMOS) aboard NASA's Hubble Space Telescope has penetrated layers of dust in a star-forming cloud to uncover a dense, craggy edifice of dust and gas . This region is called the Cone Nebula (NGC 2264), so named because, in ground-based images, it has a conical shape. NICMOS enables the Hubble telescope to see in near-infrared wavelengths of light, so that it can penetrate the dust that obscures the nebula's inner regions. But the Cone is so dense that even the near-infared 'eyes' of NICMOS can't penetrate all the way through it. The image shows the upper 0.5 light-years of the nebula. The entire nebula is 7 light-years long. The Cone resides in a turbulent star-forming region, located 2,500 light-years away in the constellation Monoceros. Radiation from hot, young stars [located beyond the top of the image] has slowly eroded the nebula over millions of years. Ultraviolet light heats the edges of the dark cloud, releasing gas into the relatively empty region of surrounding space. NICMOS has peeled away the outer layers of dust to reveal even denser dust. The denser regions give the nebula a more three-dimensional structure than can be seen in the visible-light picture at left, taken by the Advanced Camera for Surveys aboard the Hubble telescope. In peering through the dusty facade to the nebula's inner regions, NICMOS has unmasked several stars [yellow dots at upper right]. Astronomers don't know whether these stars are behind the dusty nebula or embedded in it. The four bright stars lined up on the left are in front of the nebula. The human eye cannot see infrared light, so colors have been assigned to correspond with near-infrared wavelengths. The blue light represents shorter near-infrared wavelengths and the red light corresponds to longer wavelengths. The NICMOS color composite image was made by combining photographs taken in J-band, H-band, and Paschen-alpha filters. The NICMOS images were taken on May 11, 2002. Credits for NICMOS image: NASA, the NICMOS Group (STScI, ESA), and the NICMOS Science Team (University of Arizona) Credits for ACS image: NASA, H. Ford (JHU), G. Illingworth (UCSC/LO), M.Clampin (STScI), G. Hartig (STScI), the ACS Science Team, and ESA

  1. Hypericin and pulsed laser therapy of squamous cell cancer in vitro.

    PubMed

    Bublik, Michael; Head, Christian; Benharash, Peyman; Paiva, Marcos; Eshraghi, Adrian; Kim, Taiho; Saxton, Romaine

    2006-06-01

    This in vitro study compares continuous wave and pulsed laser light at longer wavelengths for activation of the phototoxic drug hypericin in human cancer cells. Two-photon pulsed laser light now allows high-resolution fluorescent imaging of cancer cells and should provide deeper tissue penetration with near infrared light for improved detection as well as phototoxicity in human tumors. Cultured Seoul National University (SNU)-1 tumor cells from a squamous cell carcinoma (SCC) were incubated with hypericin before photoirradiation at four laser wavelengths. Phototoxicity of hypericin sensitized SCC cells was measured by dimethyl thiazoldiphenyl (MTT) tetrazolium bromide cell viability assays and by confocal fluorescence microscopy via 532-nm and infrared two-photon pulsed laser light. Phototoxic response increased linearly with hypericin dose of 0.1-2 microM, light exposure time of 5-120 sec, and pulsed dye laser wavelengths of 514-593 nm. Light energy delivery for 50% cell phototoxicity (LD50) response was 9 joules at 514 nm, 3 joules at 550 nm, and less than 1 joule at the 593 nm hypericin light absorption maxima. Fluorescence confocal microscopy revealed membrane and perinuclear localization of hypericin in the SNU cells with membrane damage seen after excitation with visible 532 nm continuous wave light or two-photon 700-950 nm picosecond pulsed laser irradiation. Hypericin may be a powerful tumor targetting drug when combined with pulsed laser light in patients with recurrent head and neck SCC.

  2. Cosmic Infrared Background Fluctuations and Zodiacal Light

    NASA Technical Reports Server (NTRS)

    Arendt, Richard G.; Kashlinsky, A.; Moseley, S. H.; Mather, J.

    2017-01-01

    We performed a specific observational test to measure the effect that the zodiacal light can have on measurements of the spatial fluctuations of the near-IR (near-infrared)background. Previous estimates of possible fluctuations caused by zodiacal light have often been extrapolated from observations of the thermal emission at longer wavelengths and low angular resolution or from IRAC (Infrared Array Camera) observations of high-latitude fields where zodiacal light is faint and not strongly varying with time. The new observations analyzed here target the COSMOS (Cosmic Evolution Survey) field at low ecliptic latitude where the zodiacal light intensity varies by factors of approximately 2 over the range of solar elongations at which the field can be observed. We find that the white-noise component of the spatial power spectrum of the background is correlated with the modeled zodiacal light intensity. Roughly half of the measured white noise is correlated with the zodiacal light, but a more detailed interpretation of the white noise is hampered by systematic uncertainties that are evident in the zodiacal light model. At large angular scales (greater than or approximately equal to 100 arcseconds) where excess power above the white noise is observed, we find no correlation of the power with the modeled intensity of the zodiacal light. This test clearly indicates that the large-scale power in the infrared background is not being caused by the zodiacal light.

  3. Light based anti-infectives: ultraviolet C irradiation, photodynamic therapy, blue light, and beyond

    PubMed Central

    Yin, Rui; Dai, Tianhong; Avci, Pinar; Jorge, Ana Elisa Serafim; de Melo, Wanessa CMA; Vecchio, Daniela; Huang, Ying-Ying; Gupta, Asheesh; Hamblin, Michael R

    2013-01-01

    Owing to the worldwide increase in antibiotic resistance, researchers are investigating alternative anti-infective strategies to which it is supposed microorganisms will be unable to develop resistance. Prominent among these strategies, is a group of approaches which rely on light to deliver the killing blow. As is well known, ultraviolet light, particularly UVC (200–280nm), is germicidal, but it has not been much developed as an anti-infective approach until recently, when it was realized that the possible adverse effects to host tissue were relatively minor compared to its high activity in killing pathogens. Photodynamic therapy is the combination of non-toxic photosensitizing dyes with harmless visible light that together produce abundant destructive reactive oxygen species (ROS). Certain cationic dyes or photosensitizers have good specificity for binding to microbial cells while sparing host mammalian cells and can be used for treating many localized infections, both superficial and even deep-seated by using fiber optic delivered light. Many microbial cells are highly sensitive to killing by blue light (400–470 nm) due to accumulation of naturally occurring photosensitizers such as porphyrins and flavins. Near infrared light has also been shown to have antimicrobial effects against certain species. Clinical applications of these technologies include skin, dental, wound, stomach, nasal, toenail and other infections which are amenable to effective light delivery. PMID:24060701

  4. Dose-dependent photochemical/photothermal toxicity of indocyanine green-based therapy on three different cancer cell lines.

    PubMed

    Ruhi, Mustafa Kemal; Ak, Ayşe; Gülsoy, Murat

    2018-03-01

    The Food and Drug Administration-approved Indocyanine Green can be used as a photosensitizer to kill cancer cells selectively. Although indocyanine green is advantageous as a photosensitizer in terms of strong absorption in the near-infrared region, indocyanine green-based cancer treatment is still not approved as a clinical method. Some reasons for this are aggregation at high concentrations, rapid clearance of the photosensitizer from the body, low singlet oxygen quantum yield, and the uncertainty concerning its action mechanism. This in vitro study focuses on two of these points: "what is the cell inhibition mechanism of indocyanine green-based therapy?" and "how the dose-dependent aggregation problem of indocyanine green alters its cell inhibition efficiency?" The following experiments were conducted to provide insight into these points. Nontoxic doses of indocyanine green and near-infrared laser were determined. The aggregation behavior of indocyanine green was verified through experiments. The singlet oxygen quantum yield of indocyanine green at different concentrations were calculated. Various indocyanine green and energy densities of near-infrared light were applied to prostate cancer, neuroblastoma, and colon cancer cells. An MTT assay was performed at the end of the first, second, and third days following the treatments to determine the cell viability. Temperature changes in the medium during laser exposure were recorded. ROS generation following the treatment was verified by using a Total Reactive Oxygen Species detection kit. An apoptosis detection test was performed to establish the cell death mechanism and, finally, the cellular uptakes of the three different cells were measured. According to the results, indocyanine green-based therapy causes cell viability decrease for three cancer cell lines by means of excessive reactive oxygen species production. Different cells have different sensitivities to the therapy possibly because of the differentiation level and structural differences. The singlet oxygen generation of indocyanine green decreases at high concentrations because of aggregation. Nevertheless, better cancer cell killing effect was observed at higher photosensitizer concentrations. This result reveals that the cellular uptake of indocyanine green was determinant for better cancer cell inhibition. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Graphene oxide/manganese ferrite nanohybrids for magnetic resonance imaging, photothermal therapy and drug delivery.

    PubMed

    Yang, Yan; Shi, Haili; Wang, Yapei; Shi, Benzhao; Guo, Linlin; Wu, Dongmei; Yang, Shiping; Wu, Huixia

    2016-01-01

    Superparamagnetic manganese ferrite (MnFe2O4) nanoparticles have been deposited on graphene oxide (GO) by the thermal decomposition of manganese (II) acetylacetonate and iron (III) acetylacetonate precursors in triethylene glycol. The resulting GO/MnFe2O4 nanohybrids show very low cytotoxicity, negligible hemolytic activity, and imperceptible in vivo toxicity. In vitro and in vivo magnetic resonance imaging experiments demonstrate that GO/MnFe2O4 nanohybrids could be used as an effective T2 contrast agent. The strong optical absorbance in the near-infrared (NIR) region and good photothermal stability of GO/MnFe2O4 nanohybrids result in the highly efficient photothermal ablation of cancer cells. GO/MnFe2O4 nanohybrids can be further loaded with doxorubicin (DOX) by π-π conjugate effect for chemotherapy. DOX release from GO/MnFe2O4 is significantly influenced by pH and can be triggered by NIR laser. The enhanced cancer cell killing by GO/MnFe2O4/DOX composites has been achieved when irradiated with near-infrared light, suggesting that the nanohybrids could deliver both DOX chemotherapy and photothermal therapy with a synergistic effect. © The Author(s) 2015.

  6. Transcranial near-infrared photobiomodulation attenuates memory impairment and hippocampal oxidative stress in sleep-deprived mice.

    PubMed

    Salehpour, Farzad; Farajdokht, Fereshteh; Erfani, Marjan; Sadigh-Eteghad, Saeed; Shotorbani, Siamak Sandoghchian; Hamblin, Michael R; Karimi, Pouran; Rasta, Seyed Hossein; Mahmoudi, Javad

    2018-03-01

    Sleep deprivation (SD) causes oxidative stress in the hippocampus and subsequent memory impairment. In this study, the effect of near-infrared (NIR) photobiomodulation (PBM) on learning and memory impairment induced by acute SD was investigated. The mice were subjected to an acute SD protocol for 72 h. Simultaneously, NIR PBM using a laser at 810 nm was delivered (once a day for 3 days) transcranially to the head to affect the entire brain of mice. The Barnes maze and the What-Where-Which task were used to assess spatial and episodic-like memories. The hippocampal levels of antioxidant enzymes and oxidative stress biomarkers were evaluated. The results showed that NIR PBM prevented cognitive impairment induced by SD. Moreover, NIR PBM therapy enhanced the antioxidant status and increased mitochondrial activity in the hippocampus of SD mice. Our findings revealed that hippocampus-related mitochondrial damage and extensive oxidative stress contribute to the occurrence of memory impairment. In contrast, NIR PBM reduced hippocampal oxidative damage, supporting the ability of 810 nm laser light to improve the antioxidant defense system and maintain mitochondrial survival. This confirms that non-invasive transcranial NIR PBM therapy ameliorates hippocampal dysfunction, which is reflected in enhanced memory function. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Eye safety related to near infrared radiation exposure to biometric devices.

    PubMed

    Kourkoumelis, Nikolaos; Tzaphlidou, Margaret

    2011-03-01

    Biometrics has become an emerging field of technology due to its intrinsic security features concerning the identification of individuals by means of measurable biological characteristics. Two of the most promising biometric modalities are iris and retina recognition, which primarily use nonionizing radiation in the infrared region. Illumination of the eye is achieved by infrared light emitting diodes (LEDs). Even if few LED sources are capable of causing direct eye damage as they emit incoherent light, there is a growing concern about the possible use of LED arrays that might pose a potential threat. Exposure to intense coherent infrared radiation has been proven to have significant effects on living tissues. The purpose of this study is to explore the biological effects arising from exposing the eye to near infrared radiation with reference to international legislation.

  8. Chemophototherapy: An Emerging Treatment Option for Solid Tumors

    PubMed Central

    Luo, Dandan; Carter, Kevin A.; Miranda, Dyego

    2016-01-01

    Near infrared (NIR) light penetrates human tissues with limited depth, thereby providing a method to safely deliver non‐ionizing radiation to well‐defined target tissue volumes. Light‐based therapies including photodynamic therapy (PDT) and laser‐induced thermal therapy have been validated clinically for curative and palliative treatment of solid tumors. However, these monotherapies can suffer from incomplete tumor killing and have not displaced existing ablative modalities. The combination of phototherapy and chemotherapy (chemophototherapy, CPT), when carefully planned, has been shown to be an effective tumor treatment option preclinically and clinically. Chemotherapy can enhance the efficacy of PDT by targeting surviving cancer cells or by inhibiting regrowth of damaged tumor blood vessels. Alternatively, PDT‐mediated vascular permeabilization has been shown to enhance the deposition of nanoparticulate drugs into tumors for enhanced accumulation and efficacy. Integrated nanoparticles have been reported that combine photosensitizers and drugs into a single agent. More recently, light‐activated nanoparticles have been developed that release their payload in response to light irradiation to achieve improved drug bioavailability with superior efficacy. CPT can potently eradicate tumors with precise spatial control, and further clinical testing is warranted. PMID:28105389

  9. Investigations of high-speed digital imaging of low-light-level events using pulsed near-infrared laser light sources

    NASA Astrophysics Data System (ADS)

    Jantzen, Connie; Slagle, Rick

    1997-05-01

    The distinction between exposure time and sample rate is often the first point raised in any discussion of high speed imaging. Many high speed events require exposure times considerably shorter than those that can be achieved solely by the sample rate of the camera, where exposure time equals 1/sample rate. Gating, a method of achieving short exposure times in digital cameras, is often difficult to achieve for exposure time requirements shorter than 100 microseconds. This paper discusses the advantages and limitations of using the short duration light pulse of a near infrared laser with high speed digital imaging systems. By closely matching the output wavelength of the pulsed laser to the peak near infrared response of current sensors, high speed image capture can be accomplished at very low (visible) light levels of illumination. By virtue of the short duration light pulse, adjustable to as short as two microseconds, image capture of very high speed events can be achieved at relatively low sample rates of less than 100 pictures per second, without image blur. For our initial investigations, we chose a ballistic subject. The results of early experimentation revealed the limitations of applying traditional ballistic imaging methods when using a pulsed infrared lightsource with a digital imaging system. These early disappointing results clarified the need to further identify the unique system characteristics of the digital imager and pulsed infrared combination. It was also necessary to investigate how the infrared reflectance and transmittance of common materials affects the imaging process. This experimental work yielded a surprising, successful methodology which will prove useful in imaging ballistic and weapons tests, as well as forensics, flow visualizations, spray pattern analyses, and nocturnal animal behavioral studies.

  10. Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring

    PubMed Central

    Avci, Pinar; Gupta, Asheesh; Sadasivam, Magesh; Vecchio, Daniela; Pam, Zeev; Pam, Nadav; Hamblin, Michael R

    2013-01-01

    Low-level laser (light) therapy (LLLT) is a fast-growing technology used to treat a multitude of conditions that require stimulation of healing, relief of pain and inflammation, and restoration of function. Although the skin is the organ that is naturally exposed to light more than any other organ, it still responds well to red and near-infrared wavelengths. The photons are absorbed by mitochondrial chromophores in skin cells. Consequently electron transport, adenosine triphosphate (ATP) nitric oxide release, blood flow, reactive oxygen species increase and diverse signaling pathways get activated. Stem cells can be activated allowing increased tissue repair and healing. In dermatology, LLLT has beneficial effects on wrinkles, acne scars, hypertrophic scars, and healing of burns. LLLT can reduce UV damage both as a treatment and as a prophylaxis. In pigmentary disorders such as vitiligo, LLLT can increase pigmentation by stimulating melanocyte proliferation and reduce depigmentation by inhibiting autoimmunity. Inflammatory diseases such as psoriasis and acne can also benefit. The non-invasive nature and almost complete absence of side-effects encourages further testing in dermatology. PMID:24049929

  11. Photothermal therapy of Lewis lung carcinoma in mice using gold nanoshells on carboxylated polystyrene spheres

    NASA Astrophysics Data System (ADS)

    Liu, Huiyu; Chen, Dong; Tang, Fangqiong; Du, Gangjun; Li, Linlin; Meng, Xianwei; Liang, Wei; Zhang, Yangde; Teng, Xu; Li, Yi

    2008-11-01

    A new approach towards the design of gold nanoshells on carboxylated polystyrene spheres (GNCPSs) is reported here. Gold nanoshells were self-assembled on the surface of carboxylated polystyrene spheres by a seed growth method. Chitosan (CHI) was used as a functional agent of carboxylated polystyrene spheres for attaching gold seeds. The surface plasmon resonance (SPR) peak of GNCPSs can be tuned, greatly redshifted, over a broad spectral range including the near-infrared (NIR) wavelength region, which provides maximal penetration of light through tissue. Irradiation of GNCPSs at their peak extinction coefficient results in the conversion of light to heat energy that produces a local rise in temperature. Our study revealed that the Lewis lung carcinoma (LLC) in mice treated with GNCPSs exposed to a low dose of NIR light (808 nm, 4 W cm-2) induced irreversible tissue damage. The tumor volumes of the treatment group by GNCPSs were significantly lower than those of control groups, with an average inhibition rate over 55% (P<0.005). This study proves that GNCPSs are promising in plasmonic photothermal tumor therapy.

  12. Penetration depth measurement of near-infrared hyperspectral imaging light for milk powder

    USDA-ARS?s Scientific Manuscript database

    The increasingly common application of near-infrared (NIR) hyperspectral imaging technique to the analysis of food powders has led to the need for optical characterization of samples. This study was aimed at exploring the feasibility of quantifying penetration depth of NIR hyperspectral imaging ligh...

  13. A Comparison of Pulse-Oximetry, Near-Infrared Spectroscopy (NIRS), and Gas Sensors for In-Cockpit Hypoxia Detection

    DTIC Science & Technology

    2012-08-29

    Pulse Oximetry: Arterial oxygen saturation (SpO2) at the index finger on the left hand was measured with a finger oximeter (Model 3900 P, Datex...minutes or until their finger O2 saturation levels dropped below 50%. Oxygen saturation was measured via the left index finger with a pulse oximeter ... saturation . Pulse oximeters have two light emitting diodes, using red (600-750 nm) and near infrared (850-1000 nm) light that penetrates the skin

  14. "Smart" theranostic lanthanide nanoprobes with simultaneous up-conversion fluorescence and tunable T1-T2 magnetic resonance imaging contrast and near-infrared activated photodynamic therapy.

    PubMed

    Zhang, Yan; Das, Gautom Kumar; Vijayaragavan, Vimalan; Xu, Qing Chi; Padmanabhan, Parasuraman; Bhakoo, Kishore K; Selvan, Subramanian Tamil; Tan, Timothy Thatt Yang

    2014-11-07

    The current work reports a type of "smart" lanthanide-based theranostic nanoprobe, NaDyF4:Yb(3+)/NaGdF4:Yb(3+),Er(3+), which is able to circumvent the up-converting poisoning effect of Dy(3+) ions to give efficient near infrared (980 nm) triggered up-conversion fluorescence, and offers not only excellent dark T2-weighted MR contrast but also tunable bright and T1-weighted MR contrast properties. Due to the efficient up-converted energy transfer from the nanocrystals to chlorin e6 (Ce6) photosensitizers loaded onto the nanocrystals, cytotoxic singlet oxygen was generated and photodynamic therapy was demonstrated. Therefore, the current multifunctional nanocrystals could be potentially useful in various image-guided diagnoses where bright or dark MRI contrast could be selectively tuned to optimize image quality, but also as an efficient and more penetrative near-infrared activated photodynamic therapy agent.

  15. Dark and Light Titan

    NASA Image and Video Library

    2010-09-08

    NASA Cassini spacecraft examines Titan dark and light seasonal hemispheric dichotomy as it images the moon with a filter sensitive to near-infrared light. This image also shows Titan north polar hood.

  16. Utilization of functional near infrared spectroscopy for non-invasive evaluation

    NASA Astrophysics Data System (ADS)

    Halim, A. A. A.; Laili, M. H.; Aziz, N. A.; Laili, A. R.; Salikin, M. S.; Rusop, M.

    2016-07-01

    The goal of this brief review is to report the techniques of functional near infrared spectroscopy for non-invasive evaluation in human study. The development of functional near infrared spectroscopy (fNIRS) technologies has advanced quantification signal using multiple wavelength and detector to solve the propagation of light inside the tissues including the absorption, scattering coefficient and to define the light penetration into tissues multilayers. There are a lot of studies that demonstrate signal from fNIRS which can be used to evaluate the changes of oxygenation level and measure the limitation of muscle performance in human brain and muscle tissues. Comprehensive reviews of diffuse reflectance based on beer lambert law theory were presented in this paper. The principle and development of fNIRS instrumentation is reported in detail.

  17. High resolution and deep tissue imaging using a near infrared acoustic resolution photoacoustic microscopy

    NASA Astrophysics Data System (ADS)

    Moothanchery, Mohesh; Sharma, Arunima; Periyasamy, Vijitha; Pramanik, Manojit

    2018-02-01

    It is always a great challenge for pure optical techniques to maintain good resolution and imaging depth at the same time. Photoacoustic imaging is an emerging technique which can overcome the limitation by pulsed light illumination and acoustic detection. Here, we report a Near Infrared Acoustic-Resolution Photoacoustic Microscopy (NIR-AR-PAM) systm with 30 MHz transducer and 1064 nm illumination which can achieve a lateral resolution of around 88 μm and imaging depth of 9.2 mm. Compared to visible light NIR beam can penetrate deeper in biological tissue due to weaker optical attenuation. In this work, we also demonstrated the in vivo imaging capabilty of NIRARPAM by near infrared detection of SLN with black ink as exogenous photoacoustic contrast agent in a rodent model.

  18. Ray trace visualization of negative refraction of light in two-dimensional air-bridged silicon photonic crystal slabs at 1.55 microm.

    PubMed

    Gan, Lin; Liu, Ya-Zhao; Li, Jiang-Yan; Zhang, Ze-Bo; Zhang, Dao-Zhong; Li, Zhi-Yuan

    2009-06-08

    We demonstrate design, fabrication, and ray trace observation of negative refraction of near-infrared light in a two-dimensional square lattice of air holes etched into an air-bridged silicon slab. Special surface morphologies are designed to reduce the impedance mismatch when light refracts from a homogeneous silicon slab into the photonic crystal slab. We clearly observed negative refraction of infrared light for TE-like modes in a broad wavelength range by using scanning near-field optical microscopy technology. The experimental results are in good agreement with finite-difference time-domain simulations. The results indicate the designed photonic crystal structure can serve as polarization beam splitter.

  19. Monte Carlo simulation of near-infrared light propagation in realistic adult head models with hair follicles

    NASA Astrophysics Data System (ADS)

    Pan, Boan; Fang, Xiang; Liu, Weichao; Li, Nanxi; Zhao, Ke; Li, Ting

    2018-02-01

    Near infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) has been used to measure brain activation, which are clinically important. Monte Carlo simulation has been applied to the near infrared light propagation model in biological tissue, and has the function of predicting diffusion and brain activation. However, previous studies have rarely considered hair and hair follicles as a contributing factor. Here, we attempt to use MCVM (Monte Carlo simulation based on 3D voxelized media) to examine light transmission, absorption, fluence, spatial sensitivity distribution (SSD) and brain activation judgement in the presence or absence of the hair follicles. The data in this study is a series of high-resolution cryosectional color photograph of a standing Chinse male adult. We found that the number of photons transmitted under the scalp decreases dramatically and the photons exported to detector is also decreasing, as the density of hair follicles increases. If there is no hair follicle, the above data increase and has the maximum value. Meanwhile, the light distribution and brain activation have a stable change along with the change of hair follicles density. The findings indicated hair follicles make influence of NIRS in light distribution and brain activation judgement.

  20. [Design of high-efficiency double compound parabolic concentrator system in near infrared noninvasive biochemical analysis].

    PubMed

    Gao, Jing; Lu, Qi-Peng; Peng, Zhong-Qi; Ding, Hai-Quan; Gao, Hong-Zhi

    2013-05-01

    High signal-to-noise ratio (SNR) of system is necessary to obtain accurate blood components in near infrared noninvasive biochemical analysis. In order to improve SNR of analytical system, high-efficiency double compound parabolic concentrator (DCPC) system was researched, which was aimed at increasing light utilization efficiency. Firstly, with the request of collection efficiency in near infrared noninvasive biochemical analysis, the characteristic of emergent rays through compound parabolic concentrator (CPC) was analyzed. Then the maximum focusing angle range of the first stage CPC was determined. Secondly, the light utilization efficiency of truncated type was compared with standard DCPC, thus the best structure parameters of DCPC system were optimized. Lastly, combined with optical parameters of skin tissue, calculations were operated when incident wavelength is 1 000 nm. The light utilization efficiency of DCPC system, CPC-focusing mirror system, and non-optical collecting system was calculated. The results show that the light utilization efficiency of the three optical systems is 1.46%, 0.84% and 0.26% respectively. So DCPC system enhances collecting ability for human diffuse reflection light, and helps improve SNR of noninvasive biochemical analysis system and overall analysis accuracy effectively.

  1. Nucleotide excision repair pathway assessment in DNA exposed to low-intensity red and infrared lasers.

    PubMed

    Fonseca, A S; Campos, V M A; Magalhães, L A G; Paoli, F

    2015-10-01

    Low-intensity lasers are used for prevention and management of oral mucositis induced by anticancer therapy, but the effectiveness of treatment depends on the genetic characteristics of affected cells. This study evaluated the survival and induction of filamentation of Escherichia coli cells deficient in the nucleotide excision repair pathway, and the action of T4endonuclease V on plasmid DNA exposed to low-intensity red and near-infrared laser light. Cultures of wild-type (strain AB1157) E. coli and strain AB1886 (deficient in uvrA protein) were exposed to red (660 nm) and infrared (808 nm) lasers at various fluences, powers and emission modes to study bacterial survival and filamentation. Also, plasmid DNA was exposed to laser light to study DNA lesions produced in vitro by T4endonuclease V. Low-intensity lasers:i) had no effect on survival of wild-type E. coli but decreased the survival of uvrA protein-deficient cells,ii) induced bacterial filamentation, iii) did not alter the electrophoretic profile of plasmids in agarose gels, andiv) did not alter the electrophoretic profile of plasmids incubated with T4 endonuclease V. These results increase our understanding of the effects of laser light on cells with various genetic characteristics, such as xeroderma pigmentosum cells deficient in nucleotide excision pathway activity in patients with mucositis treated by low-intensity lasers.

  2. Nucleotide excision repair pathway assessment in DNA exposed to low-intensity red and infrared lasers

    PubMed Central

    Fonseca, A.S.; Campos, V.M.A.; Magalhães, L.A.G.; Paoli, F.

    2015-01-01

    Low-intensity lasers are used for prevention and management of oral mucositis induced by anticancer therapy, but the effectiveness of treatment depends on the genetic characteristics of affected cells. This study evaluated the survival and induction of filamentation of Escherichia coli cells deficient in the nucleotide excision repair pathway, and the action of T4endonuclease V on plasmid DNA exposed to low-intensity red and near-infrared laser light. Cultures of wild-type (strain AB1157) E. coli and strain AB1886 (deficient in uvrA protein) were exposed to red (660 nm) and infrared (808 nm) lasers at various fluences, powers and emission modes to study bacterial survival and filamentation. Also, plasmid DNA was exposed to laser light to study DNA lesions produced in vitro by T4endonuclease V. Low-intensity lasers:i) had no effect on survival of wild-type E. coli but decreased the survival of uvrA protein-deficient cells,ii) induced bacterial filamentation, iii) did not alter the electrophoretic profile of plasmids in agarose gels, andiv) did not alter the electrophoretic profile of plasmids incubated with T4 endonuclease V. These results increase our understanding of the effects of laser light on cells with various genetic characteristics, such as xeroderma pigmentosum cells deficient in nucleotide excision pathway activity in patients with mucositis treated by low-intensity lasers. PMID:26445337

  3. Treatments for traumatic brain injury with emphasis on transcranial near-infrared laser phototherapy

    PubMed Central

    Morries, Larry D; Cassano, Paolo; Henderson, Theodore A

    2015-01-01

    Traumatic brain injury (TBI) is a growing health concern affecting civilians and military personnel. In this review, treatments for the chronic TBI patient are discussed, including pharmaceuticals, nutraceuticals, cognitive therapy, and hyperbaric oxygen therapy. All available literature suggests a marginal benefit with prolonged treatment courses. An emerging modality of treatment is near-infrared (NIR) light, which has benefit in animal models of stroke, spinal cord injury, optic nerve injury, and TBI, and in human trials for stroke and TBI. The extant literature is confounded by variable degrees of efficacy and a bewildering array of treatment parameters. Some data indicate that diodes emitting low-level NIR energy often have failed to demonstrate therapeutic efficacy, perhaps due to failing to deliver sufficient radiant energy to the necessary depth. As part of this review, we present a retrospective case series using high-power NIR laser phototherapy with a Class IV laser to treat TBI. We demonstrate greater clinical efficacy with higher fluence, in contrast to the bimodal model of efficacy previously proposed. In ten patients with chronic TBI (average time since injury 9.3 years) given ten treatments over the course of 2 months using a high-power NIR laser (13.2 W/0.89 cm2 at 810 nm or 9 W/0.89 cm2 at 810 nm and 980 nm), symptoms of headache, sleep disturbance, cognition, mood dysregulation, anxiety, and irritability improved. Symptoms were monitored by depression scales and a novel patient diary system specifically designed for this study. NIR light in the power range of 10–15 W at 810 nm and 980 nm can safely and effectively treat chronic symptoms of TBI. The clinical benefit and effects of infrared phototherapy on mitochondrial function and secondary molecular events are discussed in the context of adequate radiant energy penetration. PMID:26347062

  4. Effects of transcranial LED therapy on the cognitive rehabilitation for diffuse axonal injury due to severe acute traumatic brain injury: study protocol for a randomized controlled trial.

    PubMed

    Santos, João Gustavo Rocha Peixoto Dos; Zaninotto, Ana Luiza Costa; Zângaro, Renato Amaro; Carneiro, Ana Maria Costa; Neville, Iuri Santana; de Andrade, Almir Ferreira; Teixeira, Manoel Jacobsen; Paiva, Wellingson Silva

    2018-04-24

    Photobiomodulation describes the use of red or near-infrared light to stimulate or regenerate tissue. It was discovered that near-infrared wavelengths (800-900 nm) and red (600 nm) light-emitting diodes (LED) are able to penetrate through the scalp and skull and have the potential to improve the subnormal cellular activity of compromised brain tissue. Different experimental and clinical studies were performed to test LED therapy for traumatic brain injury (TBI) with promising results. One of the proposals of this present study is to develop different approaches to maximize the positive effects of this therapy and improve the quality of life of TBI patients. This is a double-blinded, randomized, controlled trial of patients with diffuse axonal injury (DAI) due to a severe TBI in an acute stage (less than 8 h). Thirty two patients will be randomized to active coil helmet and inactive coil (sham) groups in a 1:1 ratio. The protocol includes 18 sessions of transcranial LED stimulation (627 nm, 70 mW/cm 2 , 10 J/cm 2 ) at four points of the frontal and parietal regions for 30 s each, totaling 120 s, three times per week for 6 weeks, lasting 30 min. Patients will be evaluated with the Glasgow Outcome Scale Extended (GOSE) before stimulation and 1, 3, and 6 months after the first stimulation. The study hypotheses are as follows: (1) transcranial LED therapy (TCLT) will improve the cognitive function of DAI patients and (2) TCLT will promote beneficial hemodynamic changes in cerebral circulation. This study evaluates early and delayed effects of TCLT on the cognitive rehabilitation for DAI following severe acute TBI. There is a paucity of studies regarding the use of this therapy for cognitive improvement in TBI. There are some experimental studies and case series presenting interesting results for TBI cognitive improvement but no clinical trials. ClinicalTrials.gov, NCT03281759 . Registered on 13 September 2017.

  5. Gold nanocages covered by smart polymers for controlled release with near-infrared light.

    PubMed

    Yavuz, Mustafa S; Cheng, Yiyun; Chen, Jingyi; Cobley, Claire M; Zhang, Qiang; Rycenga, Matthew; Xie, Jingwei; Kim, Chulhong; Song, Kwang H; Schwartz, Andrea G; Wang, Lihong V; Xia, Younan

    2009-12-01

    Photosensitive caged compounds have enhanced our ability to address the complexity of biological systems by generating effectors with remarkable spatial/temporal resolutions. The caging effect is typically removed by photolysis with ultraviolet light to liberate the bioactive species. Although this technique has been successfully applied to many biological problems, it suffers from a number of intrinsic drawbacks. For example, it requires dedicated efforts to design and synthesize a precursor compound for each effector. The ultraviolet light may cause damage to biological samples and is suitable only for in vitro studies because of its quick attenuation in tissue. Here we address these issues by developing a platform based on the photothermal effect of gold nanocages. Gold nanocages represent a class of nanostructures with hollow interiors and porous walls. They can have strong absorption (for the photothermal effect) in the near-infrared while maintaining a compact size. When the surface of a gold nanocage is covered with a smart polymer, the pre-loaded effector can be released in a controllable fashion using a near-infrared laser. This system works well with various effectors without involving sophisticated syntheses, and is well suited for in vivo studies owing to the high transparency of soft tissue in the near-infrared region.

  6. Indocyanine Green-Loaded Liposomes for Light-Triggered Drug Release.

    PubMed

    Lajunen, Tatu; Kontturi, Leena-Stiina; Viitala, Lauri; Manna, Moutusi; Cramariuc, Oana; Róg, Tomasz; Bunker, Alex; Laaksonen, Timo; Viitala, Tapani; Murtomäki, Lasse; Urtti, Arto

    2016-06-06

    Light-triggered drug delivery systems enable site-specific and time-controlled drug release. In previous work, we have achieved this with liposomes containing gold nanoparticles in the aqueous core. Gold nanoparticles absorb near-infrared light and release the energy as heat that increases the permeability of the liposomal bilayer, thus releasing the contents of the liposome. In this work, we replaced the gold nanoparticles with the clinically approved imaging agent indocyanine green (ICG). The ICG liposomes were stable at storage conditions (4-22 °C) and at body temperature, and fast near-infrared (IR) light-triggered drug release was achieved with optimized phospholipid composition and a 1:50 ICG-to-lipid molar ratio. Encapsulated small molecular calcein and FITC-dextran (up to 20 kDa) were completely released from the liposomes after light exposure for 15 s. Location of ICG in the PEG layer of the liposomes was simulated with molecular dynamics. ICG has important benefits as a light-triggering agent in liposomes: fast content release, improved stability, improved possibility of liposomal size control, regulatory approval to use in humans, and the possibility of imaging the in vivo location of the liposomes based on the fluorescence of ICG. Near-infrared light used as a triggering mechanism has good tissue penetration and safety. Thus, ICG liposomes are an attractive option for light-controlled and efficient delivery of small and large drug molecules.

  7. Absolute flatness measurements of silicon mirrors by a three-intersection method by near-infrared interferometry

    PubMed Central

    2013-01-01

    Absolute flatness of three silicon plane mirrors have been measured by a three-intersection method based on the three-flat method using a near-infrared interferometer. The interferometer was constructed using a near-infrared laser diode with a 1,310-nm wavelength light where the silicon plane mirror is transparent. The height differences at the coordinate values between the absolute line profiles by the three-intersection method have been evaluated. The height differences of the three flats were 4.5 nm or less. The three-intersection method using the near-infrared interferometer was useful for measuring the absolute flatness of the silicon plane mirrors. PMID:23758916

  8. Differential response of human dermal fibroblast subpopulations to visible and near-infrared light: Potential of photobiomodulation for addressing cutaneous conditions.

    PubMed

    Mignon, Charles; Uzunbajakava, Natallia E; Castellano-Pellicena, Irene; Botchkareva, Natalia V; Tobin, Desmond J

    2018-04-17

    The past decade has witnessed a rapid expansion of photobiomodulation (PBM), demonstrating encouraging results for the treatment of cutaneous disorders. Confidence in this approach, however, is impaired not only by a lack of understanding of the light-triggered molecular cascades but also by the significant inconsistency in published experimental outcomes, design of the studies and applied optical parameters. This study aimed at characterizing the response of human dermal fibroblast subpopulations to visible and near-infrared (NIR) light in an attempt to identify the optical treatment parameters with high potential to address deficits in aging skin and non-healing chronic wounds. Primary human reticular and papillary dermal fibroblasts (DF) were isolated from the surplus of post-surgery human facial skin. An in-house developed LED-based device was used to irradiate cell cultures using six discrete wavelengths (450, 490, 550, 590, 650, and 850 nm). Light dose-response at a standard oxygen concentration (20%) at all six wavelengths was evaluated in terms of cell metabolic activity. This was followed by an analysis of the transcriptome and procollagen I production at a protein level, where cells were cultured in conditions closer to in vivo at 2% environmental oxygen and 2% serum. Furthermore, the production of reactive oxygen species (ROS) was accessed using real-time fluorescence confocal microscopy imaging. Here, production of ROS in the presence or absence of antioxidants, as well as the cellular localization of ROS, was evaluated. In terms of metabolic activity, consecutive irradiation with short-wavelength light (⇐530 nm) exerted an inhibitory effect on DF, while longer wavelengths (>=590 nm) had essentially a neutral effect. Cell behavior following treatment with 450 nm was biphasic with two distinct states: inhibitory at low- to mid- dose levels (<=30 J/cm 2 ), and cytotoxic at higher dose levels (>30 J/cm 2 ). Cell response to blue light was accompanied by a dose-dependent release of ROS that was localized in the perinuclear area close to mitochondria, which was attenuated by an antioxidant. Overall, reticular DFs exhibited a greater sensitivity to light treatment at the level of gene expression than did papillary DFs, with more genes significantly up- or down- regulated. At the intra-cellular signaling pathway level, the up- or down- regulation of vital pathways was observed only for reticular DF, after treatment with 30 J/cm 2 of blue light. At the cellular level, short visible wavelengths exerted a greater inhibitory effect on reticular DF. Several genes involved in the TGF-β signaling pathway were also affected. In addition, procollagen I production was inhibited. By contrast, 850 nm near-infrared (NIR) light (20 J/cm 2 ) exerted a stimulatory metabolic effect in these cells, with no detectable intracellular ROS formation. Here too, reticular DF were more responsive than papillary DF. This stimulatory effect was only observed under in vivo-like low oxygen conditions, corresponding to normal dermal tissue oxygen levels (approximately 2%). This study highlights a differential impact of light on human skin cells with upregulation of metabolic activity with NIR light, and inhibition of pro-collagen production and proliferation in response to blue light. These findings open-up new avenues for developing therapies for different cutaneous conditions (e.g., treatment of keloids and fibrosis) or differential therapy at distinct stages of wound healing. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  9. Inorganic photosensitizer coupled Gd-based upconversion luminescent nanocomposites for in vivo magnetic resonance imaging and near-infrared-responsive photodynamic therapy in cancers.

    PubMed

    Zhang, Ling'e; Zeng, Leyong; Pan, Yuanwei; Luo, Song; Ren, Wenzhi; Gong, An; Ma, Xuehua; Liang, Hongze; Lu, Guangming; Wu, Aiguo

    2015-03-01

    Inorganic photosensitizer coupled Gd-based upconversion luminescent (UCL) nanocomposites have potential application for both magnetic resonance imaging (MRI) and photodynamic therapy (PDT) of cancers using the light stability and biocompatibility of TiO2 inorganic photosensitizer. However, TiO2 inorganic photosensitizer could only be excited by ultraviolet (UV) light, which was harmful and weakly penetrable in tissues. In this work, folic acid (FA)-targeted NaGdF4:Yb/Tm@SiO2@TiO2 nanocomposites (FA-Gd-Si-Ti NPs) were constructed and synthesized for both in vivo MRI and near infrared (NIR)-responsive inorganic PDT, in which TiO2 component could be excited by NIR light due to the UCL performance of NaGdF4:Yb/Tm component converting NIR to UV light. The results showed the as-prepared FA-Gd-Si-Ti NPs had good biocompatibility in vitro and in vivo. Moreover, MR study indicated that FA-Gd-Si-Ti NPs were good T1-weighted MRI contrast agents with high longitudinal relaxivity (r1) of 4.53 mm(-1) s(-1), also in vivo MRI of nude mice showed "bright" signal in MCF-7 tumor. Under the irradiation of 980 nm laser at the power density of 0.6 W/cm(2) for 20 min, the viability of HeLa and MCF-7 cells incubated with FA-Gd-Si-Ti NPs could decrease from about 90 % to 35 % and 31%, respectively. Furthermore, in vivo PDT of MCF-7 tumor-bearing nude mice model showed that the inhibition ratio of tumors injected with FA-Gd-Si-Ti NPs reached up to 88.6% after 2-week treatment, compared with that of nude mice in control group. Based on the deep penetration of NIR light and the good biocompatibility of TiO2 inorganic photosensitizer, the as-prepared FA-Gd-Si-Ti NPs could have potential applications in both MRI and NIR-responsive PDT of cancers in deep tissues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Low-intensity infrared laser effects on zymosan-induced articular inflammatory response

    NASA Astrophysics Data System (ADS)

    Januária dos Anjos, Lúcia Mara; da Fonseca, Adenilson d. S.; Gameiro, Jacy; de Paoli, Flávia

    2015-03-01

    Low-level therapy laser is a phototherapy treatment that involves the application of low power light in the red or infrared wavelengths in various diseases such as arthritis. In this work, we investigated whether low-intensity infrared laser therapy could cause death by caspase-6 apoptosis or DNA damage pathways in cartilage cells after zymosaninduced articular inflammatory process. Inflammatory process was induced in C57BL/6 mouse by intra-articular injection of zymosan into rear tibio-tarsal joints. Thirty animals were divided in five groups: (I) control, (II) laser, (III) zymosan-induced, (IV) zymosan-induced + laser and (V). Laser exposure was performed after zymosan administration with low-intensity infrared laser (830 nm), power 10 mW, fluence 3.0 J/cm2 at continuous mode emission, in five doses. Twenty-four hours after last irradiation, the animals were sacrificed and the right joints fixed and demineralized. Morphological analysis was observed by hematoxylin and eosin stain, pro-apoptotic (caspase-6) was analyzed by immunocytochemistry and DNA fragmentation was performed by TUNEL assay in articular cartilage cells. Inflammatory process was observed in connective tissue near to articular cartilage, in IV and V groups, indicating zymosan effect. This process was decreased in both groups after laser treatment and dexamethasone. Although groups III and IV presented higher caspase-6 and DNA fragmentation percentages, statistical differences were not observed when compared to groups I and II. Our results suggest that therapies based on low-intensity infrared lasers could reduce inflammatory process and could not cause death by caspase-6 apoptosis or DNA damage pathways in cartilage cells after zymosan-induced articular inflammatory process.

  11. Using lead chalcogenide nanocrystals as spin mixers: a perspective on near-infrared-to-visible upconversion.

    PubMed

    Nienhaus, Lea; Wu, Mengfei; Bulović, Vladimir; Baldo, Marc A; Bawendi, Moungi G

    2018-03-01

    The process of upconversion leads to emission of photons higher in energy than the incident photons. Near-infrared-to-visible upconversion, in particular, shows promise in sub-bandgap sensitization of silicon and other optoelectronic materials, resulting in potential applications ranging from photovoltaics that exceed the Shockley-Queisser limit to infrared imaging. A feasible mechanism for near-infrared-to-visible upconversion is triplet-triplet annihilation (TTA) sensitized by colloidal nanocrystals (NCs). Here, the long lifetime of spin-triplet excitons in the organic materials that undergo TTA makes upconversion possible under incoherent excitation at relatively low photon fluxes. Since this process relies on optically inactive triplet states, semiconductor NCs are utilized as efficient spin mixers, absorbing the incident light and sensitizing the triplet states of the TTA material. The state-of-the-art system uses rubrene with a triplet energy of 1.14 eV as the TTA medium, and thus allows upconversion of light with photon energies above ∼1.1 eV. In this perspective, we review the field of lead sulfide (PbS) NC-sensitized near-infrared-to-visible upconversion, discuss solution-based upconversion, and highlight progress made on solid-state upconversion devices.

  12. DMDs for multi-object near-infrared spectrographs in astronomy

    NASA Astrophysics Data System (ADS)

    Smee, Stephen A.; Barkhouser, Robert; Hope, Stephen; Conley, Devin; Gray, Aidan; Hope, Gavin; Robberto, Massimo

    2018-02-01

    The Digital Micromirror Device (DMD), typically used in projection screen technology, has utility in instrumentation for astronomy as a digitally programmable slit in a spectrograph. When placed at an imaging focal plane the device can be used to selectively direct light from astronomical targets into the optical path of a spectrograph, while at the same time directing the remaining light into an imaging camera, which can be used for slit alignment, science imaging, or both. To date the use of DMDs in astronomy has been limited, especially for instruments that operate in the near infrared (1 - 2.5 μm). This limitation is due in part to a host of technical challenges with respect to DMDs that, to date, have not been thoroughly explored. Those challenges include operation at cryogenic temperature, control electronics that facilitate DMD use at these temperatures, window coatings properly coated for the near infrared bandpass, and scattered light. This paper discusses these technical challenges and presents progress towards understanding and mitigating them.

  13. Astronomers Set a New Galaxy Distance Record

    NASA Image and Video Library

    2015-05-06

    This is a Hubble Space Telescope image of the farthest spectroscopically confirmed galaxy observed to date (inset). It was identified in this Hubble image of a field of galaxies in the CANDELS survey (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey). NASA’s Spitzer Space Telescope also observed the unique galaxy. The W. M. Keck Observatory was used to obtain a spectroscopic redshift (z=7.7), extending the previous redshift record. Measurements of the stretching of light, or redshift, give the most reliable distances to other galaxies. This source is thus currently the most distant confirmed galaxy known, and it appears to also be one of the brightest and most massive sources at that time. The galaxy existed over 13 billion years ago. The near-infrared light image of the galaxy (inset) has been colored blue as suggestive of its young, and hence very blue, stars. The CANDELS field is a combination of visible-light and near-infrared exposures. Credits: NASA, ESA, P. Oesch (Yale U.)

  14. Self-assembled KCu7S4 nanowire monolayers for self-powered near-infrared photodetectors.

    PubMed

    Wang, You-Yi; Wu, Ya-Dong; Peng, Wei; Song, Yong-Hong; Wang, Bao; Wu, Chun-Yan; Lu, Yang

    2018-06-13

    Near infrared light (NIR) photodetectors based on one-dimensional semiconductor nanowires have generated considerable interest due to their practical application in versatile fields. We present a facile yet efficient approach to rationally integrating KCu7S4 semiconductor nanowires by the Langmuir-Blodgett (LB) technique. A self-powered near infrared (NIR) light photodetector is fabricated by transferring a close-packed KCu7S4 nanowire monolayer to the surface of a silicon wafer. The as-fabricated Si/KCu7S4 heterojunction with a close-packed and well-aligned nanowire array exhibits splendid photovoltaic performance when illuminated by NIR light, allowing the detection of NIR light without an exterior power supply. The photodetector exhibits a high sensitivity to NIR light (980 nm, 295.3 μW cm-2) with responsivity (R) 15 mA W-1 and detectivity (D*) 2.15 × 1012 cm Hz1/2 W-1. Significantly, the device shows the capability to work under high pulsed light irradiation up to 50 kHz with a high-speed response (response time τr 7.4 μs and recovery time τf 8.6 μs). This facilitates the fabrication of low-cost and high-speed photodetectors and integrated optoelectronic sensor circuitry.

  15. Far-Field to Near-Field Coupling for Enhancing Light-Matter Interaction

    NASA Astrophysics Data System (ADS)

    Bonakdar, Alireza

    This thesis reports on theoretical, modeling, and experimental research within the framework of a key scientific question, which is enhancing the coupling between diffraction-limited far-field and sub-wavelength quantum emitter/absorber. A typical optoelectronic device delivers an optical process such as light detection (e.g. photodetector) or light intensity modulation (e.g. electro-absorptive modulator). In conventional devices, optical process is in the form of far-field or guided wave modes. The main aim of this thesis is to show that converting these modes into near-field domain can enhance the performance of the optoelectronic device. Light in the form of far-field can be converted into near-field domain by the optical antenna. Among different optoelectronic devices, this thesis focuses mainly on integrating the optical antenna with infrared photodetectors. The available semiconductors have weak infrared absorption that reduces light detection efficiency. Integration of the optical antenna with infrared absorber (such as quantum wells in quantum well infrared photodetector (QWIP)) increases the infrared absorption. Particularly this integration is favorable as the optical antenna has low metallic loss in infrared region. The author of this thesis believes that optical antenna has unique properties in confining light on the scale of deep sub-wavelength, enhancing electric field intensity and delivering optical energy to semiconductor absorbers. These properties are reaching into practical applications only if overall optical performance is low loss, parameter free (independent of optical parameters such a polarization and angle of incident) and broadband. In this thesis, the integration of optical antenna with infrared photodetectors and thermophotovoltaic are researched and developed which satisfy the aforementioned criteria. In addition, several different optical antennas have been designed, fabricated and characterized in order to analyze and demonstrate the improvement of infrared absorption. In terms of design, novel optical antennas were simulated and proposed for a variety of infrared photodetectors such as a quantum well infrared photodetector, metal-insulator-metal detector, Schottky infrared photodetector, and two-photon absorption infrared detector. Antenna analyzes are not limited to light detection as a chapter of this thesis devoted on design and develop of a low power and ultrafast all-optical/optomechanical switchable antenna. The rest of the manuscript contains the novel lithography method in order to fabricate optical antennas with low cost and in cm-scale area. The method is based on the microsphere photolithography that expose photoresist underneath each microsphere with a focused intensive light -so called photonic nanojet. The developed lithography method takes advantage of microscopic range of optical path (micro-optics) in microsphere lenses that allows to push the exposure wavelength beyond deep UV region, where the refractive optics becomes impractical due to severe material absorption. The author believes that micro-optics lithography is an excellent candidate for large area and high throughput fabrication of sub-100-nm feature sizes in periodic array. In particular, this method facilitates the feasibility of metasurfaces and metamaterials, optical coating with efficient photon extraction/trapping, and highly sensitive bio-sensors in near IR and visible ranges of spectrum.

  16. Therapeutic effect of forearm low level light treatment on blood flow, oxygenation, and oxygen consumption

    NASA Astrophysics Data System (ADS)

    Wang, Pengbo; Sun, Jiajing; Meng, Lingkang; Li, Zebin; Li, Ting

    2018-02-01

    Low level light/laser therapy (LLLT) is considered as a novel, non-invasive, and potential therapy in a variety of psychological and physical conditions, due to its effective intricate photobiomodulation. The mechanism of LLLT is that when cells are stimulated by photons, mitochondria produce a large quantity of ATP, which accelerates biochemical responses in the cell. It is of great significance to gain a clear insight into the change or interplay of various physiological parameters. In this study, we used functional near-infrared spectroscopy (fNIRS) and venous-occlusion plethysmography to measure the LLLT-induced changes in blood flow, oxygenation, and oxygen consumption in human forearms in vivo. Six healthy human participants (4 males and 2 females) were administered with 810-nm light emitted by LED array in ten minutes and blood flow, oxygenation and oxygen consumption were detected in the entire experiment. We found that LLLT induced an increase of blood flow and oxygen consumption on the treated site. Meanwhile, LLLT took a good role in promoting oxygenation of regional tissue, which was indicated by a significant increase of oxygenated hemoglobin concentration (Δ[HbO2]), a nearly invariable deoxygenated hemoglobin concentration (Δ[Hb]) and a increase of differential hemoglobin concentration (Δ[HbD] = Δ[HbO2] - Δ[Hb]). These results not only demonstrate enormous potential of LLLT, but help to figure out mechanisms of photobiomodulation.

  17. Advantages of using gold hollow nanoshells in cancer photothermal therapy

    NASA Astrophysics Data System (ADS)

    Abbasi, Sattar; Servatkhah, Mojtaba; Keshtkar, Mohammad Mehdi

    2016-08-01

    Lots of studies have been conducted on the optical properties of gold nanoparticles in the first region of near infrared (650 nm-950 nm), however new findings show that the second region of near-infrared (1000 nm-1350 nm) penetrates to the deeper tissues of the human body. Therefore, using the above-mentioned region in photo-thermal therapy (PTT) of cancer will be more appropriate. In this paper, absorption efficiency is calculated for gold spherical and rod-shaped nanoshells by the finite element method (FEM). The results show that the surface plasmon frequency of these nanostructures is highly dependent on the dimension and thickness of shell and it can be adjusted to the second region of near-infrared. Thus, due to their optical tunability and their high absorption efficiency the hollow nanoshells are the most appropriate options for eradicating cancer tissues.

  18. Bactericidal effect of visible light in the presence of erythrosine on Porphyromonas gingivalis and Fusobacterium nucleatum compared with diode laser, an in vitro study.

    PubMed

    Habiboallah, Ghanbari; Mahdi, Zakeri; Mahbobeh, Naderi Nasab; Mina, Zareian Jahromi; Sina, Faghihi; Majid, Zakeri

    2014-12-27

    Recently, photodynamic therapy (PDT) has been introduced as a new modality in oral bacterial decontamination. Besides, the ability of laser irradiation in the presence of photosensitizing agent to lethal effect on oral bacteria is well documented. Current research aims to evaluate the effect of photodynamic killing of visible blue light in the presence of plaque disclosing agent erythrosine as photosensitizer on Porphyromonas gingivalis associated with periodontal bone loss and Fusobacterium nucleatum associated with soft tissue inflammation, comparing with the near-infrared diode laser. Standard suspension of P. gingivalis and F. nucleatum were exposed to Light Emitting Diode (LED) (440-480 nm) used to photopolymerize composite resine dental restoration in combination with erythrosine (22 µm) up to 5 minutes. Bacterial sample were also exposed to a near-infrared diode laser (wavelength, 830 nm), using identical irradiation parameters for comparison. Bacterial samples from each treatment groups (radiation-only group, erythrosine-only group and light or laser with erythrosine group) were subcultured onto the surface of agar plates. Survival of these bacteria was determined by counting the number of colony forming units (CFU) after incubation. Exposure to visible blue light and diode laser in conjugation with erythrosine significantly reduced both species examined viability, whereas erythrosine-treated samples exposed to visible light suggested a statically meaningful differences comparing to diode laser. In addition, bactericidal effect of visible light or diode laser alone on P. gingivalis as black-pigmented bacteria possess endogenous porphyrins was noticeably. Our result suggested that visible blue light source in the presence of plaque disclosing agent erythrosine could can be consider as potential approach of PDT to kill the main gram-negative periodontal pathogens. From a clinical standpoint, this regimen could be established as an additional minimally invasive antibacterial treatment of plaque induced periodontal pathologies.

  19. Magnetic field enhanced photothermal effect of Fe3O4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Pan, Pengfei; Lin, Yawen; Gan, Zhixing; Luo, Xiaobin; Zhou, Weiping; Zhang, Ning

    2018-03-01

    Photothermal and magnetothermal effects are promising in hyperthermia for cancer therapy. However, the development of safe treatments with limited side-effects requires a relatively-high thermal efficiency triggered by mild near-infrared (NIR) light and alternating magnetic field (HAC), which remains a formidable challenge. In this work, a magnetic field enhanced photothermal effect (MFEP) of Fe3O4 nanoparticles is proposed and investigated systematically. The results suggest remarkable temperature increments of 9.59 to 36.90 °C under irradiation of NIR with different light power densities (808 nm, 0-6.98 W/cm2) combined with a certain magnetic field (HAC = 1.5 kA/m at 90 kHz). The rise of temperature induced by MFEP is substantially larger than the sum of isolated photothermal and magnetothermal effects, which is attributed to the hot-phonon bottleneck effect. The MFEP of Fe3O4 nanoparticles could serve as an effective treatment for cancer therapy in the future.

  20. Application and possible mechanisms of combining LLLT (low level laser therapy), infrared hyperthermia and ionizing radiation in the treatment of cancer

    NASA Astrophysics Data System (ADS)

    Abraham, Edward H.; Woo, Van H.; Harlin-Jones, Cheryl; Heselich, Anja; Frohns, Florian

    2014-02-01

    Benefit of concomitant infrared hyperthermia and low level laser therapy and ionizing radiation is evaluated in this study. The purpose/objectives: presentation with locally advanced bulky superficial tumors is clinically challenging. To enhance the efficacy of chemotherapy and IMRT (intensity-modulated radiation therapy) and/or electron beam therapy we have developed an inexpensive and clinically effective infrared hyperthermia approach that combines black-body infrared radiation with halogen spectrum radiation and discrete wave length infrared clinical lasers LLLT. The goal is to produce a composite spectrum extending from the far infrared to near infrared and portions of the visible spectrum with discrete penetrating wavelengths generated by the clinical infrared lasers with frequencies of 810 nm and/or 830 nm. The composite spectrum from these sources is applied before and after radiation therapy. We monitor the surface and in some cases deeper temperatures with thermal probes, but use an array of surface probes as the limiting safe thermal constraint in patient treatment while at the same time maximizing infrared entry to deeper tissue layers. Fever-grade infrared hyperthermia is produced in the first centimeters while non-thermal infrared effects act at deeper tissue layers. The combination of these effects with ionizing radiation leads to improved tumor control in many cancers.

  1. [Effects of Light Near-Infrared Radiation on Rats Assessed by Succinate Dehydrogenase Activity in Lymphocytes on Blood Smears].

    PubMed

    Khunderyakova, N V; Zakharchenko, A V; Zakharchenko, M V; Muller, H; Fedotcheva, I; Kondrashova, M N

    2015-01-01

    Biological effects of light near infrared radiation (850 nm), with modulation acoustic frequency of 101 Hz, was studied. The study was conducted on rats, the effect was recorded by succinate dehydrogenase activity in lymphocytes on the blood smear after administration of the activating dose of adrenaline, which simulates the state of the organism in the early stages of the pathogenic effects (stress). A pronounced regulating effect of infrared radiation on the activity of succinate dehydrogenase in animals activated by adrenaline was shown. Infrared radiation has a normalizing effect reducing the degree of inhibition or activation of the enzyme induced by adrenaline and had no effect on the control animals. Thus, by modulating the activity of succinate dehydrogenase infrared radiation regulates energy production in the mitochondria supported by the most powerful oxidation substrate--succinic acid, which is especially pronounced under stress.

  2. QEPAS nitric oxide sensor based on a mid-infrared fiber-coupled quantum cascade laser

    NASA Astrophysics Data System (ADS)

    Ren, Wei; Shi, Chao; Wang, Zhen; Yao, Chenyu

    2017-04-01

    We report a quartz-enhanced photoacoustic sensor (QEPAS) for nitric oxide (NO) detection using a mid-infrared fibercoupled quantum cascade laser (QCL) near 5.2 μm. The QCL radiation was coupled into an InF3 fiber (100 μm core diameter) for light delivery to the quartz tuning fork, a tiny piezoelectric element converting the acoustic wave induced mechanical vibration to the gas-absorption associated electrical signal. This mid-infrared fiber can achieve nearly single-mode light delivery for the target wavelength. The off-beam configuration was adopted for the fiber-coupled detection considering its simpler installation, optical alignment and comparative sensitivity to the traditional on-beam setup.

  3. All-nitride AlxGa1−xN:Mn/GaN distributed Bragg reflectors for the near-infrared

    PubMed Central

    Capuzzo, Giulia; Kysylychyn, Dmytro; Adhikari, Rajdeep; Li, Tian; Faina, Bogdan; Tarazaga Martín-Luengo, Aitana; Bonanni, Alberta

    2017-01-01

    Since the technological breakthrough prompted by the inception of light emitting diodes based on III-nitrides, these material systems have emerged as strategic semiconductors not only for the lighting of the future, but also for the new generation of high-power electronic and spintronic devices. While III-nitride optoelectronics in the visible and ultraviolet spectral range is widely established, all-nitride efficient devices in the near-infrared (NIR) are still wanted. Here, through a comprehensive protocol of design, modeling, epitaxial growth and in-depth characterization, we develop AlxGa1−xN:Mn/GaN NIR distributed Bragg reflectors and we show their efficiency in combination with GaN:(Mn,Mg) layers containing Mn-Mgk complexes optically active in the near-infrared range of wavelengths. PMID:28198432

  4. Water-soluble core/shell nanoparticles for proton therapy through particle-induced radiation

    NASA Astrophysics Data System (ADS)

    Park, Jeong Chan; Jung, Myung-Hwan; Kim, Maeng Jun; Kim, Kye-Ryung

    2015-02-01

    Metallic nanoparticles have been used in biomedical applications such as magnetic resonance imaging (MRI), therapy, and drug delivery systems. Metallic nanoparticles as therapeutic tools have been demonstrated using radio-frequency magnetic fields or near-infrared light. Recently, therapeutic applications of metallic nanomaterials combined with proton beams have been reported. Particle-induced radiation from metallic nanoparticles, which can enhance the therapeutic effects of proton therapy, was released when the nanoparticles were bombarded by a high-energy proton beam. Core/shell nanoparticles, especially Au-coated magnetic nanoparticles, have drawn attention in biological applications due to their attractive characteristics. However, studies on the phase transfer of organic-ligand-based core/shell nanoparticles into water are limited. Herein, we demonstrated that hydrophobic core/shell structured nanomaterials could be successfully dispersed in water through chloroform/surfactant mixtures. The effects of the core/shell nanomaterials and the proton irradiation on Escherichia coli (E. coli) were also explored.

  5. Strategies to Improve Cancer Photothermal Therapy Mediated by Nanomaterials.

    PubMed

    de Melo-Diogo, Duarte; Pais-Silva, Cleide; Dias, Diana R; Moreira, André F; Correia, Ilídio J

    2017-05-01

    The deployment of hyperthermia-based treatments for cancer therapy has captured the attention of different researchers worldwide. In particular, the application of light-responsive nanomaterials to mediate hyperthermia has revealed promising results in several pre-clinical assays. Unlike conventional therapies, these nanostructures can display a preferential tumor accumulation and thus mediate, upon irradiation with near-infrared light, a selective hyperthermic effect with temporal resolution. Different types of nanomaterials such as those based on gold, carbon, copper, molybdenum, tungsten, iron, palladium and conjugated polymers have been used for this photothermal modality. This progress report summarizes the different strategies that have been applied so far for increasing the efficacy of the photothermal therapeutic effect mediated by nanomaterials, namely those that improve the accumulation of nanomaterials in tumors (e.g. by changing the corona composition or through the functionalization with targeting ligands), increase nanomaterials' intrinsic capacity to generate photoinduced heat (e.g. by synthesizing new nanomaterials or assembling nanostructures) or by optimizing the parameters related to the laser light used in the irradiation process (e.g. by modulating the radiation wavelength). Overall, the development of new strategies or the optimization and combination of the existing ones will surely give a major contribution for the application of nanomaterials in cancer PTT. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. 5-ALA photopreparation using pulsed NIR enhances skin fluorescence via temperature-independent cell signaling pathways

    NASA Astrophysics Data System (ADS)

    Barolet, Augustin C.; Cormack, Gregory; Barolet, Daniel

    2018-02-01

    The effect of near infrared light (940 nm) on the conversion of 5-aminolevulinic acid (5-ALA) to PpIX, a compound involved in photodynamic therapy (PDT), was examined. The back skin of three test subjects was irradiated with continuous wavelength and pulsed infrared light at 940 nm. These irradiations took place 50-53, 24-29, and 8-14 hours prior to the application of the 5-ALA. After a three-hour incubation period with 5-ALA, a FluoDerm™device was used to measure the fluorescence of the skin (emitting wavelength: 400-420 nm; measuring excitation wavelength: 610-720 nm), a direct indication of the activity of 5-ALA. 5-ALA must penetrate the skin and then be converted to PpIX before any fluorescence increase can be observed. Results: For two patients (one was disqualified), the continuous wavelength, 50 hour pre-irradiation condition, the FluoDerm readings showed a 19 to 23% increase in fluorescence (p = 0.05) compared to the no-irradiation, 5-ALA only control.

  7. Mechanisms of low level light therapy

    NASA Astrophysics Data System (ADS)

    Hamblin, Michael R.; Demidova, Tatiana N.

    2006-02-01

    The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing tissue damage has been known for almost forty years since the invention of lasers. Originally thought to be a peculiar property of laser light (soft or cold lasers), the subject has now broadened to include photobiomodulation and photobiostimulation using non-coherent light. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial. This likely is due to two main reasons; firstly the biochemical mechanisms underlying the positive effects are incompletely understood, and secondly the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. In particular a biphasic dose response has been frequently observed where low levels of light have a much better effect than higher levels. This introductory review will cover some of the proposed cellular chromophores responsible for the effect of visible light on mammalian cells, including cytochrome c oxidase (with absorption peaks in the near infrared) and photoactive porphyrins. Mitochondria are thought to be a likely site for the initial effects of light, leading to increased ATP production, modulation of reactive oxygen species and induction of transcription factors. These effects in turn lead to increased cell proliferation and migration (particularly by fibroblasts), modulation in levels of cytokines, growth factors and inflammatory mediators, and increased tissue oxygenation. The results of these biochemical and cellular changes in animals and patients include such benefits as increased healing in chronic wounds, improvements in sports injuries and carpal tunnel syndrome, pain reduction in arthritis and neuropathies, and amelioration of damage after heart attacks, stroke, nerve injury and retinal toxicity.

  8. High-Contrast Near-Infrared Imaging Polarimetry of the Protoplanetary Disk around RY Tau

    NASA Technical Reports Server (NTRS)

    Takami, Michihiro; Karr, Jennifer L.; Hashimoto, Jun; Kim, Hyosun; Wisenewski, John; Henning, Thomas; Grady, Carol; Kandori, Ryo; Hodapp, Klaus W.; Kudo, Tomoyuki; hide

    2013-01-01

    We present near-infrared coronagraphic imaging polarimetry of RY Tau. The scattered light in the circumstellar environment was imaged at H-band at a high resolution (approx. 0.05) for the first time, using Subaru-HiCIAO. The observed polarized intensity (PI) distribution shows a butterfly-like distribution of bright emission with an angular scale similar to the disk observed at millimeter wavelengths. This distribution is offset toward the blueshifted jet, indicating the presence of a geometrically thick disk or a remnant envelope, and therefore the earliest stage of the Class II evolutionary phase. We perform comparisons between the observed PI distribution and disk models with: (1) full radiative transfer code, using the spectral energy distribution (SED) to constrain the disk parameters; and (2) monochromatic simulations of scattered light which explore a wide range of parameters space to constrain the disk and dust parameters. We show that these models cannot consistently explain the observed PI distribution, SED, and the viewing angle inferred by millimeter interferometry. We suggest that the scattered light in the near-infrared is associated with an optically thin and geometrically thick layer above the disk surface, with the surface responsible for the infrared SED. Half of the scattered light and thermal radiation in this layer illuminates the disk surface, and this process may significantly affect the thermal structure of the disk.

  9. Using near-infrared spectroscopy to resolve the species, gender, age, and the presence of Wolbachia infection in laboratory-reared Drosophila

    USDA-ARS?s Scientific Manuscript database

    The aim of the study was to determine the accuracy of near-infrared spectroscopy (NIRS) in determining species, gender, age and the presence of the common endosymbiont Wolbachia in laboratory reared Drosophila. NIRS measures absorption of light by organic molecules. Initially, a calibration model wa...

  10. Near-infrared spectral methods for noninvasively measuring blood glucose

    NASA Astrophysics Data System (ADS)

    Fei, Sun; Kong, Deyi; Mei, Tao; Tao, Yongchun

    2004-05-01

    Determination of blood glucose concentrations in diabetic patients is a frequently occurring procedure and an important tool for diabetes management. Use of noninvasive detection techniques can relieve patients from the pain of frequent finger pokes and avoid the infection of disease via blood. This thesis discusses current research and analyzes the advantages and shortages of different measurement methods, including: optical methods (Transmission, Polarimetry and scattering), then, we give emphasis to analyze the technology of near-infrared (NIR) spectra. NIR spectral range 700 nm ~2300 nm was used because of its good transparency for biological tissue and presence of glucose absorption band. In this work, we present an outline of noninvasive blood glucose measurement. A near-infrared light beam is passed through the finger, and the spectral components of the emergent beam are measured using spectroscopic techniques. The device includes light sources having the wavelengths of 600 nm - 1800 nm to illuminate the tissue. Receptors associated with the light sources for receiving light and generating a transmission signal representing the light transmitted are also provided. Once a transmission signal is received by receptors, and the high and low values from each of the signals are stored in the device. The averaged values are then analyzed to determine the glucose concentration, which is displayed on the device.

  11. Effect of near-infrared rays on female menstrual pain in Korea.

    PubMed

    Lee, Jin-Min; Kim, Kye-Ha

    2017-09-01

    Most Korean women who experience menstrual pain have reported taking pain medicine and making use of complementary alternative therapies. However, because some interventions may cause side effects, more effective pain-relieving measures need to be identified. This study using a non-equivalent group design, evaluated the effects of near-infrared rays on dysmenorrhea among Korean women. The experimental group wore a near-infrared ray abdominal belt for the duration of one menstrual cycle until the end of the menstrual period, while the control group used hot packs. The level of menstrual pain, menstrual pain duration, and pain medicine use were measured. The menstrual pain, average menstrual pain duration, and use of analgesics were reduced in the near-infrared rays group. The results of this study indicate that the near-infrared ray LED belt was effective in reducing menstrual pain, menstrual pain duration compared to the use of analgesics in Korean women with dysmenorrhea. Therefore, near-infrared rays may be used to relieve menstrual pain and improve the quality of life of women with dysmenorrhea in Korea. © 2017 John Wiley & Sons Australia, Ltd.

  12. IR CMOS: near infrared enhanced digital imaging (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Pralle, Martin U.; Carey, James E.; Joy, Thomas; Vineis, Chris J.; Palsule, Chintamani

    2015-08-01

    SiOnyx has demonstrated imaging at light levels below 1 mLux (moonless starlight) at video frame rates with a 720P CMOS image sensor in a compact, low latency camera. Low light imaging is enabled by the combination of enhanced quantum efficiency in the near infrared together with state of the art low noise image sensor design. The quantum efficiency enhancements are achieved by applying Black Silicon, SiOnyx's proprietary ultrafast laser semiconductor processing technology. In the near infrared, silicon's native indirect bandgap results in low absorption coefficients and long absorption lengths. The Black Silicon nanostructured layer fundamentally disrupts this paradigm by enhancing the absorption of light within a thin pixel layer making 5 microns of silicon equivalent to over 300 microns of standard silicon. This results in a demonstrate 10 fold improvements in near infrared sensitivity over incumbent imaging technology while maintaining complete compatibility with standard CMOS image sensor process flows. Applications include surveillance, nightvision, and 1064nm laser see spot. Imaging performance metrics will be discussed. Demonstrated performance characteristics: Pixel size : 5.6 and 10 um Array size: 720P/1.3Mpix Frame rate: 60 Hz Read noise: 2 ele/pixel Spectral sensitivity: 400 to 1200 nm (with 10x QE at 1064nm) Daytime imaging: color (Bayer pattern) Nighttime imaging: moonless starlight conditions 1064nm laser imaging: daytime imaging out to 2Km

  13. Research on capability of detecting ballistic missile by near space infrared system

    NASA Astrophysics Data System (ADS)

    Lu, Li; Sheng, Wen; Jiang, Wei; Jiang, Feng

    2018-01-01

    The infrared detection technology of ballistic missile based on near space platform can effectively make up the shortcomings of high-cost of traditional early warning satellites and the limited earth curvature of ground-based early warning radar. In terms of target detection capability, aiming at the problem that the formula of the action distance based on contrast performance ignores the background emissivity in the calculation process and the formula is only valid for the monochromatic light, an improved formula of the detecting range based on contrast performance is proposed. The near space infrared imaging system parameters are introduced, the expression of the contrastive action distance formula based on the target detection of the near space platform is deduced. The detection range of the near space infrared system for the booster stage ballistic missile skin, the tail nozzle and the tail flame is calculated. The simulation results show that the near-space infrared system has the best effect on the detection of tail-flame radiation.

  14. Near-infrared localized surface plasmon resonance of self-growing W-doped VO2 nanoparticles at room temperature

    NASA Astrophysics Data System (ADS)

    Nishikawa, Kazutaka; Kishida, Yoshihiro; Ito, Kota; Tamura, Shin-ichi; Takeda, Yasuhiko

    2017-11-01

    Nanoparticles (NPs) of vanadium dioxide (VO2) in the metal state exhibit localized surface plasmon resonance (LSPR) at 1200-1600 nm, which fills the gap between the absorption ranges of silicon and the LSPR of conventional transparent conductor NPs (ZnO:Al, In2O3:Sn, etc.). However, two issues of the lithographic process for NP formation and the metal-insulator transition temperature (69 °C) higher than room temperature have made it difficult to use VO2 NPs for applications such as energy conversion devices, near infrared (NIR) light detectors, and bio-therapy. In this study, we developed a self-growing process for tungsten (W)-doped VO2 NPs that are in the metal state at room temperature, using sputter deposition and post-lamp annealing. The changes in the LSPR peak wavelengths with the NP size were well controlled by changing the deposited film thickness and oxygen pressure during the post-annealing treatment. The presented results resolve the difficulties of using the metal-insulator transition material VO2 for practical NIR utilization.

  15. Ambient-Light-Canceling Camera Using Subtraction of Frames

    NASA Technical Reports Server (NTRS)

    Morookian, John Michael

    2004-01-01

    The ambient-light-canceling camera (ALCC) is a proposed near-infrared electronic camera that would utilize a combination of (1) synchronized illumination during alternate frame periods and (2) subtraction of readouts from consecutive frames to obtain images without a background component of ambient light. The ALCC is intended especially for use in tracking the motion of an eye by the pupil center corneal reflection (PCCR) method. Eye tracking by the PCCR method has shown potential for application in human-computer interaction for people with and without disabilities, and for noninvasive monitoring, detection, and even diagnosis of physiological and neurological deficiencies. In the PCCR method, an eye is illuminated by near-infrared light from a lightemitting diode (LED). Some of the infrared light is reflected from the surface of the cornea. Some of the infrared light enters the eye through the pupil and is reflected from back of the eye out through the pupil a phenomenon commonly observed as the red-eye effect in flash photography. An electronic camera is oriented to image the user's eye. The output of the camera is digitized and processed by algorithms that locate the two reflections. Then from the locations of the centers of the two reflections, the direction of gaze is computed. As described thus far, the PCCR method is susceptible to errors caused by reflections of ambient light. Although a near-infrared band-pass optical filter can be used to discriminate against ambient light, some sources of ambient light have enough in-band power to compete with the LED signal. The mode of operation of the ALCC would complement or supplant spectral filtering by providing more nearly complete cancellation of the effect of ambient light. In the operation of the ALCC, a near-infrared LED would be pulsed on during one camera frame period and off during the next frame period. Thus, the scene would be illuminated by both the LED (signal) light and the ambient (background) light during one frame period, and would be illuminated with only ambient (background) light during the next frame period. The camera output would be digitized and sent to a computer, wherein the pixel values of the background-only frame would be subtracted from the pixel values of the signal-plus-background frame to obtain signal-only pixel values (see figure). To prevent artifacts of motion from entering the images, it would be necessary to acquire image data at a rate greater than the standard video rate of 30 frames per second. For this purpose, the ALCC would exploit a novel control technique developed at NASA s Jet Propulsion Laboratory for advanced charge-coupled-device (CCD) cameras. This technique provides for readout from a subwindow [region of interest (ROI)] within the image frame. Because the desired reflections from the eye would typically occupy a small fraction of the area within the image frame, the ROI capability would make it possible to acquire and subtract pixel values at rates of several hundred frames per second considerably greater than the standard video rate and sufficient to both (1) suppress motion artifacts and (2) track the motion of the eye between consecutive subtractive frame pairs.

  16. False color viewing device

    DOEpatents

    Kronberg, J.W.

    1992-10-20

    A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage. 7 figs.

  17. False color viewing device

    DOEpatents

    Kronberg, James W.

    1992-01-01

    A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.

  18. False color viewing device

    DOEpatents

    Kronberg, J.W.

    1991-05-08

    This invention consists of a viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching, the user`s eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.

  19. Gold nanorod reshaping in vitro and in vivo using a continuous wave laser

    PubMed Central

    Zhou, Yu; Shah, Anant; Ruenraroengsak, Pakatip; Gallina, Maria Elena; Hanna, George B.; Cass, Anthony E. G.; Porter, Alexandra E.; Bamber, Jeffrey; Elson, Daniel S.

    2017-01-01

    Gold nanorods (GNRs) are increasingly being investigated for cancer theranostics as they possess features which lend themselves in equal measures as contrast agents and catalysts for photothermal therapy. Their optical absorption spectral peak wavelength is determined by their size and shape. Photothermal therapy using GNRs is typically established using near infrared light as this allows sufficient penetration into the tumour matrix. Continuous wave (CW) lasers are the most commonly applied source of near infrared irradiation on GNRs for tumour photothermal therapy. It is perceived that large tumours may require fractionated or prolonged irradiation. However the true efficacy of repeated or protracted CW irradiation on tumour sites using the original sample of GNRs remains unclear. In this study spectroscopy and transmission electron microscopy are used to demonstrate that GNRs reshape both in vitro and in vivo after CW irradiation, which reduces their absorption efficiency. These changes were sustained throughout and beyond the initial period of irradiation, resulting from a spectral blue-shift and a considerable diminution in the absorption peak of GNRs. Solid subcutaneous tumours in immunodeficient BALB/c mice were subjected to GNRs and analysed with electron microscopy pre- and post-CW laser irradiation. This phenomenon of thermally induced GNR reshaping can occur at relatively low bulk temperatures, well below the bulk melting point of gold. Photoacoustic monitoring of GNR reshaping is also evaluated as a potential clinical aid to determine GNR absorption and reshaping during photothermal therapy. Aggregation of particles was coincidentally observed following CW irradiation, which would further diminish the subsequent optical absorption capacity of irradiated GNRs. It is thus established that sequential or prolonged applications of CW laser will not confer any additional photothermal effect on tumours due to significant attenuations in the peak optical absorption properties of GNRs following primary laser irradiation. PMID:29045438

  20. Near-infrared face recognition utilizing open CV software

    NASA Astrophysics Data System (ADS)

    Sellami, Louiza; Ngo, Hau; Fowler, Chris J.; Kearney, Liam M.

    2014-06-01

    Commercially available hardware, freely available algorithms, and authors' developed software are synergized successfully to detect and recognize subjects in an environment without visible light. This project integrates three major components: an illumination device operating in near infrared (NIR) spectrum, a NIR capable camera and a software algorithm capable of performing image manipulation, facial detection and recognition. Focusing our efforts in the near infrared spectrum allows the low budget system to operate covertly while still allowing for accurate face recognition. In doing so a valuable function has been developed which presents potential benefits in future civilian and military security and surveillance operations.

  1. Generating structured light with phase helix and intensity helix using reflection-enhanced plasmonic metasurface at 2 μm

    NASA Astrophysics Data System (ADS)

    Zhao, Yifan; Du, Jing; Zhang, Jinrun; Shen, Li; Wang, Jian

    2018-04-01

    Mid-infrared (2-20 μm) light has been attracting great attention in many areas of science and technology. Beyond the extended wavelength range from visible and near-infrared to mid-infrared, shaping spatial structures may add opportunities to grooming applications of mid-infrared photonics. Here, we design and fabricate a reflection-enhanced plasmonic metasurface and demonstrate efficient generation of structured light with the phase helix and intensity helix at 2 μm. This work includes two distinct aspects. First, structured light (phase helix, intensity helix) generation at 2 μm, which is far beyond the ability of conventional spatial light modulators, is enabled by the metasurface with sub-wavelength engineered structures. Second, the self-referenced intensity helix against environmental noise is generated without using a spatially separated light. The demonstrations may open up advanced perspectives to structured light applications at 2 μm, such as phase helix for communications and non-communications (imaging, sensing) and intensity helix for enhanced microscopy and advanced metrology.

  2. Influence of earlobe thickness on near infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Jiang, Jingying; Wang, Tianpei; Li, Si; Li, Lin; Liu, Jiajia; Xu, Kexin

    2017-03-01

    Near-infrared spectroscopy has been recognized as a potential technology for noninvasive blood glucose sensing. However, the detected spectral signal is unstable mainly because of (1) the weak light absorption of glucose itself within NIR range, (2) the influence of temperature and individual differences of biotissue. Our previous results demonstrated that the synergistic effect of both transmittance and reflectance could enhance the strength of the detection signal. In this talk, we design a set of experiments to analyze the effect of earlobe thickness on Near Infrared spectroscopic measurement by using home-made optical fiber probe within the wavelength of 1000-1600nm. Firstly, we made a MC simulation of single-layer skin model and five-layer skin model to get the diffused transmittance spectra and diffused reflectance spectra under different optaical path lengths. And then we obtain the spectra of the earlobes from different volunteers by the same way. The experimental results showed that with the increase of the thickness,the light intensity of diffused transmittance decreases, and the light intensity of diffused reflectance remaines substantially unchanged.

  3. Stray light modeling of the James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM)

    NASA Astrophysics Data System (ADS)

    Rohrbach, Scott O.; Irvin, Ryan G.; Seals, Lenward T.; Skelton, Dennis L.

    2016-09-01

    This paper describes an integrated stray light model of each Science Instrument (SI) in the Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope (JWST) and the Optical Telescope Element Simulator (OSIM), the light source used to characterize the performance of ISIM in cryogenic-vacuum tests at the Goddard Space Flight Center (GSFC). We present three cases where this stray light model was integral to solving questions that arose during the testing campaign - 1) ghosting and coherent diffraction from hardware surfaces in the Near Infrared Imager and Slitless Spectrograph (NIRISS) GR700XD grism mode, 2) ghost spots in the Near Infrared Camera (NIRCam) GRISM modes, and 3) scattering from knife edges of the NIRCam focal plane array masks.

  4. Investigation of star polymer nanoshells for use in diagnostic imaging and photothermal cancer therapy applications

    NASA Astrophysics Data System (ADS)

    Gomez, Lizabeth

    Gold nanoshells can be designed to possess high light scattering and strong absorption of near-infrared light. Thus, they have the potential to be used in biological applications as contrast agents for diagnostic imaging as well as for thermal ablation of tumor cells in future cancer treatments. In this study, gold nanoshells with dye-loaded star polymer cores were investigated. Uniform near-infrared gold nanoshells with 100 nm diameters were successfully generated using different batches of star polymer templates and were characterized by UV-visible spectroscopy and scanning electron microscopy. The star polymers used were block copolymer structures with a hydrophobic polystyrene (PS) core and a hydrophilic poly(N,N-dimethylaminoethylmethracrylate) (DMAEMA) outer shell. Within this work, a general procedure was established in order to achieve a desired gold nanoshell size regardless of the star polymer batch used, since the synthesis process conditions can cause star polymers to vary in size as well in the number and length of amino-functionalized arms. Control of the gold nanoshell diameter was optimized after an in-depth analysis of the synthesis parameters that affected the formation and final size of the dye-loaded star polymer gold nanoshells. The main parameters examined were pH of the gold seeds used to nucleate the templates and the ratio of star polymer to gold hydroxide used during the growth of the outer gold shell.

  5. Near infrared low level laser therapy and cell proliferation: the emerging role of redox sensitive signal transduction pathways.

    PubMed

    Migliario, Mario; Sabbatini, Maurizio; Mortellaro, Carmen; Renò, Filippo

    2018-05-02

    Lasers devices are widely used in various medical fields (e.g. surgery, dermatology, dentistry, rehabilitative medicine, etc) for different applications, ranging from surgical ablation of tissues to biostimulation and pain relief. Laser is an electromagnetic radiation which effects on biological tissues strongly depends on a number of physical parameters. Laser wavelength, energy output, irradiation time and modality, temperature and tissue penetration properties have to be set up according to the clinical target tissue and the desired effect. A less than optimal operational settings, in fact, could result in a null or even lethal effect. According to the first law of photobiology, light absorption requires the presence of a specific photoacceptor that after excitation could induce the activation of downstream signaling pathways. Low level lasers operating in the red/near infrared portion of the light spectra are generally used for biostimulation purposes, a particular therapeutic application based on the radiant energy ability to induce non-thermal responses in living cells. Biostimulation process generally promotes cell survival and proliferation. Emerging evidences support a low level laser stimulation mediated increase in "good" ROS (reactive oxygen species), able to activate redox sensitive signal transduction pathways such as Nrf-2, NF-kB, ERK which act as key redox checkpoints. This article is protected by copyright. All rights reserved.

  6. IrisDenseNet: Robust Iris Segmentation Using Densely Connected Fully Convolutional Networks in the Images by Visible Light and Near-Infrared Light Camera Sensors

    PubMed Central

    Arsalan, Muhammad; Naqvi, Rizwan Ali; Kim, Dong Seop; Nguyen, Phong Ha; Owais, Muhammad; Park, Kang Ryoung

    2018-01-01

    The recent advancements in computer vision have opened new horizons for deploying biometric recognition algorithms in mobile and handheld devices. Similarly, iris recognition is now much needed in unconstraint scenarios with accuracy. These environments make the acquired iris image exhibit occlusion, low resolution, blur, unusual glint, ghost effect, and off-angles. The prevailing segmentation algorithms cannot cope with these constraints. In addition, owing to the unavailability of near-infrared (NIR) light, iris recognition in visible light environment makes the iris segmentation challenging with the noise of visible light. Deep learning with convolutional neural networks (CNN) has brought a considerable breakthrough in various applications. To address the iris segmentation issues in challenging situations by visible light and near-infrared light camera sensors, this paper proposes a densely connected fully convolutional network (IrisDenseNet), which can determine the true iris boundary even with inferior-quality images by using better information gradient flow between the dense blocks. In the experiments conducted, five datasets of visible light and NIR environments were used. For visible light environment, noisy iris challenge evaluation part-II (NICE-II selected from UBIRIS.v2 database) and mobile iris challenge evaluation (MICHE-I) datasets were used. For NIR environment, the institute of automation, Chinese academy of sciences (CASIA) v4.0 interval, CASIA v4.0 distance, and IIT Delhi v1.0 iris datasets were used. Experimental results showed the optimal segmentation of the proposed IrisDenseNet and its excellent performance over existing algorithms for all five datasets. PMID:29748495

  7. IrisDenseNet: Robust Iris Segmentation Using Densely Connected Fully Convolutional Networks in the Images by Visible Light and Near-Infrared Light Camera Sensors.

    PubMed

    Arsalan, Muhammad; Naqvi, Rizwan Ali; Kim, Dong Seop; Nguyen, Phong Ha; Owais, Muhammad; Park, Kang Ryoung

    2018-05-10

    The recent advancements in computer vision have opened new horizons for deploying biometric recognition algorithms in mobile and handheld devices. Similarly, iris recognition is now much needed in unconstraint scenarios with accuracy. These environments make the acquired iris image exhibit occlusion, low resolution, blur, unusual glint, ghost effect, and off-angles. The prevailing segmentation algorithms cannot cope with these constraints. In addition, owing to the unavailability of near-infrared (NIR) light, iris recognition in visible light environment makes the iris segmentation challenging with the noise of visible light. Deep learning with convolutional neural networks (CNN) has brought a considerable breakthrough in various applications. To address the iris segmentation issues in challenging situations by visible light and near-infrared light camera sensors, this paper proposes a densely connected fully convolutional network (IrisDenseNet), which can determine the true iris boundary even with inferior-quality images by using better information gradient flow between the dense blocks. In the experiments conducted, five datasets of visible light and NIR environments were used. For visible light environment, noisy iris challenge evaluation part-II (NICE-II selected from UBIRIS.v2 database) and mobile iris challenge evaluation (MICHE-I) datasets were used. For NIR environment, the institute of automation, Chinese academy of sciences (CASIA) v4.0 interval, CASIA v4.0 distance, and IIT Delhi v1.0 iris datasets were used. Experimental results showed the optimal segmentation of the proposed IrisDenseNet and its excellent performance over existing algorithms for all five datasets.

  8. The cosmic infrared background experiment-2 (CIBER-2) for studying the near-infrared extragalactic background light

    NASA Astrophysics Data System (ADS)

    Shirahata, Mai; Arai, Toshiaki; Battle, John; Bock, James; Cooray, Asantha; Enokuchi, Akito; Hristov, Viktor; Kanai, Yoshikazu; Kim, Min Gyu; Korngut, Phillip; Lanz, Alicia; Lee, Dae-Hee; Mason, Peter; Matsumoto, Toshio; Matsuura, Shuji; Morford, Tracy; Ohnishi, Yosuke; Park, Won-Kee; Sano, Kei; Takeyama, Norihide; Tsumura, Kohji; Wada, Takehiko; Wang, Shiang-Yu; Zemcov, Michael

    2016-07-01

    We present the current status of the Cosmic Infrared Background ExpeRiment-2 (CIBER-2) project, whose goal is to make a rocket-borne measurement of the near-infrared Extragalactic Background Light (EBL), under a collaboration with U.S.A., Japan, South Korea, and Taiwan. The EBL is the integrated light of all extragalactic sources of emission back to the early Universe. At near-infrared wavelengths, measurement of the EBL is a promising way to detect the diffuse light from the first collapsed structures at redshift z˜10, which are impossible to detect as individual sources. However, recently, the intra-halo light (IHL) model is advocated as the main contribution to the EBL, and our new result of the EBL fluctuation from CIBER-1 experiment is also supporting this model. In this model, EBL is contributed by accumulated light from stars in the dark halo regions of low- redshift (z<2) galaxies, those were tidally stripped by the interaction of satellite dwarf galaxies. Thus, in order to understand the origin of the EBL, both the spatial fluctuation observations with multiple wavelength bands and the absolute spectroscopic observations for the EBL are highly required. After the successful initial CIBER- 1 experiment, we are now developing a new instrument CIBER-2, which is comprised of a 28.5-cm aluminum telescope and three broad-band, wide-field imaging cameras. The three wide-field (2.3×2.3 degrees) imaging cameras use the 2K×2K HgCdTe HAWAII-2RG arrays, and cover the optical and near-infrared wavelength range of 0.5-0.9 μm, 1.0-1.4 μm and 1.5-2.0 μm, respectively. Combining a large area telescope with the high sensitivity detectors, CIBER-2 will be able to measure the spatial fluctuations in the EBL at much fainter levels than those detected in previous CIBER-1 experiment. Additionally, we will use a linear variable filter installed just above the detectors so that a measurement of the absolute spectrum of the EBL is also possible. In this paper, the scientific motivation and the expected performance for CIBER-2 will be presented. The detailed designs of the telescope and imaging cameras will also be discussed, including the designs of the mechanical, cryogenic, and electrical systems.

  9. Simulation of nanoparticle-mediated near-infrared thermal therapy using GATE

    PubMed Central

    Cuplov, Vesna; Pain, Frédéric; Jan, Sébastien

    2017-01-01

    Application of nanotechnology for biomedicine in cancer therapy allows for direct delivery of anticancer agents to tumors. An example of such therapies is the nanoparticle-mediated near-infrared hyperthermia treatment. In order to investigate the influence of nanoparticle properties on the spatial distribution of heat in the tumor and healthy tissues, accurate simulations are required. The Geant4 Application for Emission Tomography (GATE) open-source simulation platform, based on the Geant4 toolkit, is widely used by the research community involved in molecular imaging, radiotherapy and optical imaging. We present an extension of GATE that can model nanoparticle-mediated hyperthermal therapy as well as simple heat diffusion in biological tissues. This new feature of GATE combined with optical imaging allows for the simulation of a theranostic scenario in which the patient is injected with theranostic nanosystems that can simultaneously deliver therapeutic (i.e. hyperthermia therapy) and imaging agents (i.e. fluorescence imaging). PMID:28663855

  10. Simple route to (NH4)xWO3 nanorods for near infrared absorption

    NASA Astrophysics Data System (ADS)

    Guo, Chongshen; Yin, Shu; Dong, Qiang; Sato, Tsugio

    2012-05-01

    Described here is how to synthesize one-dimensional ammonium tungsten bronze ((NH4)xWO3) by a facile solvothermal approach in which ethylene glycol and acetic acid were employed as solvents and ammonium paratungstate was used as a starting material, as well as how to develop the near infrared absorption properties of (NH4)xWO3 nanorods for application as a solar light control filter. The as-obtained product was characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry (TG), atomic force microscope (AFM) and UV-Vis-NIR spectra. The SEM and TEM images clearly revealed that the obtained sample possessed rod/fiber-like morphologies with diameters around 120 nm. As determined by UV-Vis-NIR optical measurement, the thin film consisted of (NH4)xWO3 nanoparticles, which can selectively transmit most visible lights, but strongly absorb the near-infrared (NIR) lights and ultraviolet rays. These interesting optical properties make the (NH4)xWO3 nanorods suitable for the solar control windows.Described here is how to synthesize one-dimensional ammonium tungsten bronze ((NH4)xWO3) by a facile solvothermal approach in which ethylene glycol and acetic acid were employed as solvents and ammonium paratungstate was used as a starting material, as well as how to develop the near infrared absorption properties of (NH4)xWO3 nanorods for application as a solar light control filter. The as-obtained product was characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry (TG), atomic force microscope (AFM) and UV-Vis-NIR spectra. The SEM and TEM images clearly revealed that the obtained sample possessed rod/fiber-like morphologies with diameters around 120 nm. As determined by UV-Vis-NIR optical measurement, the thin film consisted of (NH4)xWO3 nanoparticles, which can selectively transmit most visible lights, but strongly absorb the near-infrared (NIR) lights and ultraviolet rays. These interesting optical properties make the (NH4)xWO3 nanorods suitable for the solar control windows. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr30612c

  11. In vitro evaluation of low-intensity light radiation on murine melanoma (B16F10) cells.

    PubMed

    Peidaee, P; Almansour, N M; Pirogova, E

    2016-03-01

    Changes in the energy state of biomolecules induced by electromagnetic radiation lead to changes in biological functions of irradiated biomolecules. Using the RRM approach, it was computationally predicted that far-infrared light irradiation in the range of 3500-6000 nm affects biological activity of proto-oncogene proteins. This in vitro study evaluates quantitatively and qualitatively the effects of selected far-infrared exposures in the computationally determined wavelengths on mouse melanoma B16F10 cells and Chinese hamster ovarian (CHO) cells by MTT (thiazolyl blue tetrazolium bromide) cell proliferation assay and confocal laser-scanning microscopy (CLSM). This paper also presents the findings obtained from irradiating B16F10 and CHO cells by the selected wavelengths in visible and near-infrared range. The MTT results show that far-infrared wavelength irradiation induces detrimental effect on cellular viability of B16F10 cells, while that of normal CHO cells is not affected considerably. Moreover, CLSM images demonstrate visible cellular detachment of cancer cells. The observed effects support the hypothesis that far-infrared light irradiation within the computationally determined wavelength range induces biological effect on cancer cells. From irradiation of selected visible and near-infrared wavelengths, no visible changes were detected in cellular viability of either normal or cancer cells.

  12. Multifunctional hollow gold nanoparticles designed for triple combination therapy and CT imaging.

    PubMed

    Park, Jaesook; Park, Jin; Ju, Eun Jin; Park, Seok Soon; Choi, Jinhyang; Lee, Jae Hee; Lee, Kyoung Jin; Shin, Seol Hwa; Ko, Eun Jung; Park, Intae; Kim, Chulhee; Hwang, Jung Jin; Lee, Jung Shin; Song, Si Yeol; Jeong, Seong-Yun; Choi, Eun Kyung

    2015-06-10

    Hollow gold nanoparticles (HGNP) are a novel class of hybrid metal nanoparticles whose unique optical and morphological properties have spawned new applications including more effective cancer therapy. The shell thickness of HGNPs can tune the surface plasmon resonance to the near infrared light, resulting in photothermal ablation of tumors with optimal light penetration in tissue. The hollow cavity within a HGNP is able to accommodate a high payload of chemotherapeutic agents. They have also been used for enhancing radiosensitization in tumors during radiotherapy due to the high X-ray absorption capability of gold particles. However, no report has yet been published that utilize HGNPs for the triple combination therapy and CT imaging. In this study, we synthesized HGNPs which exhibit better response to radiation for therapy and imaging and demonstrated the effects of combined chemotherapy, thermal and radiotherapy. This combination strategy presented delayed tumor growth by 4.3-fold and reduced tumor's weight by 6.8-fold compared to control tumors. In addition, we demonstrated the feasibility of HGNP as a CT imaging agent. It is expected that translating these capabilities to human cancer patients could dramatically increase the antitumor effect and potentially overcome resistance to chemotherapeutic agents and radiation. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. In-situ second harmonic generation by cancer cell targeting ZnO nanocrystals to effect photodynamic action in subcellular space.

    PubMed

    Gu, Bobo; Pliss, Artem; Kuzmin, Andrey N; Baev, Alexander; Ohulchanskyy, Tymish Y; Damasco, Jossana A; Yong, Ken-Tye; Wen, Shuangchun; Prasad, Paras N

    2016-10-01

    This paper introduces the concept of in-situ upconversion of deep penetrating near infrared light via second harmonic generation from ZnO nanocrystals delivered into cells to effect photo activated therapies, such as photodynamic therapy, which usually require activation by visible light with limited penetration through biological tissues. We demonstrated this concept by subcellular activation of a photodynamic therapy drug, Chlorin e6, excited within its strong absorption Soret band by the second harmonic (SH) light, generated at 409 nm by ZnO nanocrystals, which were targeted to cancer cells and internalized through the folate-receptor mediated endocytosis. By a combination of theoretical modeling and experimental measurements, we show that SH light, generated in-situ by ZnO nanocrystals significantly contributes to activation of photosensitizer, leading to cell death through both apoptotic and necrotic pathways initiated in the cytoplasm. This targeted photodynamic action was studied using label-free Coherent Anti-Stokes Raman Scattering imaging of the treated cells to monitor changes in the distribution of native cellular proteins and lipids. We found that initiation of photodynamic therapy with upconverted light led to global reduction in the intracellular concentration of macromolecules, likely due to suppression of proteins and lipids synthesis, which could be considered as a real-time indicator of cellular damage from photodynamic treatment. In prospective applications this in-situ photon upconversion could be further extended using ZnO nanocrystals surface functionalized with a specific organelle targeting group, provided a powerful approach to identify and consequently maximize a cellular response to phototherapy, selectively initiated in a specific cellular organelle. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Unsupported thin film beam splitter

    NASA Technical Reports Server (NTRS)

    Bastien, R. C.; Scheuerman, R. J.

    1972-01-01

    Multilayer beam splitter system yielding nearly equal broadband infrared reflectance and transmittance in the 5 to 50 micron spectral region has been developed which will significantly reduce size and cost of light path compensating devices in infrared spectral instruments.

  15. Response of Grape Leaf Spectra to Phylloxera Infestation

    NASA Technical Reports Server (NTRS)

    Johnson, Lee F.

    1999-01-01

    During the 1993 growing season, leaf reflectance and chlorophyll concentrations were monitored with respect to phylloxera (root-louse) infestation in a Napa Valley (California) vineyard. Study plots were established in areas of severely infested, mildly infested, and uninfested sections of the vineyard. A handheld chlorophyll meter, measuring leaf transmittance of near-infrared and red light, confirmed that reduced foliar chlorophyll concentrations were symptomatic of phylloxera stress in the sample vines. Bidirectional reflectance measurements of green and near-infrared light, taken on fresh leaves with a laboratory spectrophotometer, were related to chlorophyll concentration but did not allow discrimination of mildly infested from uninfested vines.

  16. Image-guided surgery using near-infrared fluorescent light: from bench to bedside

    NASA Astrophysics Data System (ADS)

    Boogerd, Leonora S. F.; Handgraaf, Henricus J. M.; van de Velde, Cornelis J. H.; Vahrmeijer, Alexander L.

    2015-03-01

    Due to its relatively high tissue penetration, near-infrared (NIR; 700-900 nm) fluorescent light has the potential to visualize structures that need to be resected (e.g. tumors, lymph nodes) and structures that need to be spared (e.g. nerves, ureters, bile ducts). Until now, most clinical trials have focused on suboptimal, non-targeted dyes. Although successful, a new era in image-guided surgery has begun by the introduction of tumor-targeted agents. In this paper, we will describe how tumor-targeted NIR fluorescent imaging can be applied in a clinical setting.

  17. The Infrared Hubble Diagram of Type Ia Supernovae

    NASA Astrophysics Data System (ADS)

    Krisciunas, Kevin

    Photometry of Type Ia supernovae reveals that these objects are standardizable candles in optical passbands - the peak luminosities are related to the rate of decline after maximum light. In the near-infrared bands, there is essentially a characteristic brightness at maximum light for each photometric band. Thus, in the near-infrared they are better than standardizable candles; they are essentially standard candles. Their absolute magnitudes are known to ±0.15 magnitude or better. The infrared observations have the extra advantage that interstellar extinction by dust along the line of sight is a factor of 3-10 smaller than in the optical B- and V -bands. The size of any systematic errors in the infrared extinction corrections typically become smaller than the photometric errors of the observations. Thus, we can obtain distances to the hosts of Type Ia supernovae to ±8 % or better. This is particularly useful for extragalactic astronomy and precise measurements of the dark energy component of the universe.

  18. Investigation of the Comparative Effects of Red and Infrared Laser Therapy on Skeletal Muscle Repair in Diabetic Rats.

    PubMed

    Assis, Lívia; Manis, Camila; Fernandes, Kelly Rossetti; Cabral, Daniel; Magri, Angela; Veronez, Suellen; Renno, Ana Claudia Muniz

    2016-07-01

    The aim of this study was to evaluate the in vivo response of 2 different laser wavelengths (red and infrared) on skeletal muscle repair process in diabetic rats. Forty Wistar rats were randomly divided into 4 experimental groups: basal control-nondiabetic and muscle-injured animals without treatment (BC); diabetic muscle-injured without treatment (DC); diabetic muscle-injured, treated with red laser (DCR) and infrared laser (DCIR). The injured region was irradiated daily for 7 consecutive days, starting immediately after the injury using a red (660 nm) and an infrared (808 nm) laser. The histological results demonstrated in both treated groups (red and infrared wavelengths) a modulation of the inflammatory process and a better tissue organization located in the site of the injury. However, only infrared light significantly reduced the injured area and increased MyoD and myogenin protein expression. Moreover, both red and infrared light increased the expression of the proangiogenic vascular endothelial growth factor and reduced the cyclooxygenase 2 protein expression. These results suggest that low-level laser therapy was efficient in promoting skeletal muscle repair in diabetic rats. However, the effect of infrared wavelength was more pronounced by reducing the area of the injury and modulating the expression proteins related to the repair.

  19. Near-infrared light activation of quenched liposomal Ce6 for synergistic cancer phototherapy with effective skin protection.

    PubMed

    Feng, Liangzhu; Tao, Danlei; Dong, Ziliang; Chen, Qian; Chao, Yu; Liu, Zhuang; Chen, Meiwan

    2017-05-01

    Current photodynamic therapy (PDT) is suffering from limited efficacy towards hypoxia tumors and severe post-treatment photo-toxicity such as light-induced skin damages. To make PDT more effective in cancer treatment while being patient-comfortable, herein, a hexylamine conjugated chlorin e6 (hCe6) as the photosensitizer together with a lipophilic near-infrared (NIR) dye 1,1'-dioctadecyl-3,3,3',3'-tetramethylindotricarbocyanine iodide (DiR) are co-encapsulated into polyethylene glycol (PEG) shelled liposomes. In the obtained DiR-hCe6-liposome, the photosensitizing effect of hCe6 is quenched by DiR via fluorescence resonance energy transfer (FRET). Interestingly, upon irradiation with a 785-nm NIR laser to photobleach DiR, both fluorescence and photodynamic effect of hCe6 in DiR-hCe6-liposome would be activated. Meanwhile, such NIR irradiation applied on tumors of mice with intravenous injection of DiR-hCe6-liposome could result in mild photothermal heating, which in turn would promote intra-tumor blood flow and relieve tumor hypoxia, contributing to the enhanced photodynamic tumor treatment. Importantly, compared to hCe6-loaded liposomes, DiR-hCe6-liposome without being activated by the 785-nm laser shows much lower skin photo-toxicity, demonstrating its great skin protection effect. This work demonstrates a promising yet simple strategy to prepare NIR-light-activatable photodynamic theranostics for synergistic cancer phototherapy, which is featured high specificity/efficacy in tumor treatment with minimal photo-toxicity towards the skin. Copyright © 2016. Published by Elsevier Ltd.

  20. Neural responses of rat cortical layers due to infrared neural modulation and photoablation of thalamocortical brain slices

    NASA Astrophysics Data System (ADS)

    Jenkins, J. Logan; Kao, Chris C.; Cayce, Jonathan M.; Mahadevan-Jansen, Anita; Jansen, E. Duco

    2017-02-01

    Infrared neural modulation (INM) is a label-free method for eliciting neural activity with high spatial selectivity in mammalian models. While there has been an emphasis on INM research towards applications in the peripheral nervous system and the central nervous system (CNS), the biophysical mechanisms by which INM occurs remains largely unresolved. In the rat CNS, INM has been shown to elicit and inhibit neural activity, evoke calcium signals that are dependent on glutamate transients and astrocytes, and modulate inhibitory GABA currents. So far, in vivo experiments have been restricted to layers I and II of the rat cortex which consists mainly of astrocytes, inhibitory neurons, and dendrites from deeper excitatory neurons owing to strong absorption of light in these layers. Deeper cortical layers (III-VI) have vastly different cell type composition, consisting predominantly of excitatory neurons which can be targeted for therapies such as deep brain stimulation. The neural responses to infrared light of deeper cortical cells have not been well defined. Acute thalamocortical brain slices will allow us to analyze the effects of INS on various components of the cortex, including different cortical layers and cell populations. In this study, we present the use of photoablation with an erbium:YAG laser to reduce the thickness of the dead cell zone near the cutting surface of brain slices. This technique will allow for more optical energy to reach living cells, which should contribute the successful transduction of pulsed infrared light to neural activity. In the future, INM-induced neural responses will lead to a finer characterization of the parameter space for the neuromodulation of different cortical cell types and may contribute to understanding the cell populations that are important for allowing optical stimulation of neurons in the CNS.

  1. Fabrication of thin-film thermoelectric generators with ball lenses for conversion of near-infrared solar light

    NASA Astrophysics Data System (ADS)

    Ito, Yoshitaka; Mizoshiri, Mizue; Mikami, Masashi; Kondo, Tasuku; Sakurai, Junpei; Hata, Seiichi

    2017-06-01

    We designed and fabricated thin-film thermoelectric generators (TEGs) with ball lenses, which separated visible light and near-infrared (NIR) solar light using a chromatic aberration. The transmitted visible light was used as daylight and the NIR light was used for thermoelectric generation. Solar light was estimated to be separated into the visible light and NIR light by a ray tracing method. 92.7% of the visible light was used as daylight and 9.9% of the NIR light was used for thermoelectric generation. Then, the temperature difference of the pn junctions of the TEG surface was 0.71 K, determined by heat conduction analysis using a finite element method. The thin-film TEGs were fabricated using lithography and deposition processes. When the solar light (A.M. 1.5) was irradiated to the TEGs, the open-circuit voltage and maximum power were 4.5 V/m2 and 51 µW/m2, respectively. These TEGs are expected to be used as an energy supply for Internet of Things sensors.

  2. Visible Light-Assisted High-Performance Mid-Infrared Photodetectors Based on Single InAs Nanowire.

    PubMed

    Fang, Hehai; Hu, Weida; Wang, Peng; Guo, Nan; Luo, Wenjin; Zheng, Dingshan; Gong, Fan; Luo, Man; Tian, Hongzheng; Zhang, Xutao; Luo, Chen; Wu, Xing; Chen, Pingping; Liao, Lei; Pan, Anlian; Chen, Xiaoshuang; Lu, Wei

    2016-10-12

    One-dimensional InAs nanowires (NWs) have been widely researched in recent years. Features of high mobility and narrow bandgap reveal its great potential of optoelectronic applications. However, most reported work about InAs NW-based photodetectors is limited to the visible waveband. Although some work shows certain response for near-infrared light, the problems of large dark current and small light on/off ratio are unsolved, thus significantly restricting the detectivity. Here in this work, a novel "visible light-assisted dark-current suppressing method" is proposed for the first time to reduce the dark current and enhance the infrared photodetection of single InAs NW photodetectors. This method effectively increases the barrier height of the metal-semiconductor contact, thus significantly making the device a metal-semiconductor-metal (MSM) photodiode. These MSM photodiodes demonstrate broadband detection from less than 1 μm to more than 3 μm and a fast response of tens of microseconds. A high detectivity of ∼10 12 Jones has been achieved for the wavelength of 2000 nm at a low bias voltage of 0.1 V with corresponding responsivity of as much as 40 A/W. Even for the incident wavelength of 3113 nm, a detectivity of ∼10 10 Jones and a responsivity of 0.6 A/W have been obtained. Our work has achieved an extended detection waveband for single InAs NW photodetector from visible and near-infrared to mid-infrared. The excellent performance for infrared detection demonstrated the great potential of narrow bandgap NWs for future infrared optoelectronic applications.

  3. Photocatalytic hydrogen evolution over β-iron silicide under infrared-light irradiation.

    PubMed

    Yoshimizu, Masaharu; Kobayashi, Ryoya; Saegusa, Makoto; Takashima, Toshihiro; Funakubo, Hiroshi; Akiyama, Kensuke; Matsumoto, Yoshihisa; Irie, Hiroshi

    2015-02-18

    We investigated the ability of β-iron silicide (β-FeSi2) to serve as a hydrogen (H2)-evolution photocatalyst due to the potential of its conduction band bottom, which may allow thermodynamically favorable H2 evolution in spite of its small band-gap of 0.80 eV. β-FeSi2 had an apparent quantum efficiency for H2 evolution of ∼24% up to 950 nm (near infrared light), in the presence of the dithionic acid ion (S2O6(2-)) as a sacrificial agent. It was also sensitive to infrared light (>1300 nm) for H2 evolution.

  4. A Chelator-Free Multifunctional [64Cu]-CuS Nanoparticle Platform for Simultaneous Micro-PET/CT Imaging and Photothermal Ablation Therapy

    PubMed Central

    Zhou, Min; Zhang, Rui; Huang, Miao; Lu, Wei; Song, Shaoli; Melancon, Marites P.; Tian, Mei; Liang, Dong; Li, Chun

    2010-01-01

    We synthesized and evaluated a novel class of chelator-free [64Cu]-CuS nanoparticles (NPs) suitable for both PET imaging and as photothermal coupling agents for photothermal ablation. [64Cu]-CuS NPs were simple to make, possessed excellent stability, and allowed robust noninvasive micro-PET imaging. Furthermore, CuS NPs displayed strong absorption in the near-infrared (NIR) region (peak 930 nm), passive targeting prefers the tumor site, and mediated ablation of U87 tumor cells upon exposure to NIR light both in vitro and in vivo after either intratumoral or intravenous injection. The combination of small diameter (~11 nm diameter), strong NIR absorption, and integration of 64Cu as a structural component makes [64Cu]-CuS NPs ideally suited for multifunctional molecular imaging and therapy. PMID:20942456

  5. Copper Selenide Nanocrystals for Photothermal Therapy

    PubMed Central

    Hessel, Colin M.; Pattani, Varun; Rasch, Michael; Panthani, Matthew G.; Koo, Bonil; Tunnell, James W.; Korgel, Brian A.

    2011-01-01

    Ligand-stabilized copper selenide (Cu2−xSe) nanocrystals, approximately 16 nm in diameter, were synthesized by a colloidal hot injection method and coated with amphiphilic polymer. The nanocrystals readily disperse in water and exhibit strong near infrared (NIR) optical absorption with a high molar extinction coefficient of 7.7 × 107 cm−1 M−1 at 980 nm. When excited with 800 nm light, the Cu2−xSe nanocrystals produce significant photothermal heating with a photothermal transduction efficiency of 22%, comparable to nanorods and nanoshells of gold (Au). In vitro photothermal heating of Cu2−xSe nanocrystals in the presence of human colorectal cancer cell (HCT-116) led to cell destruction after 5 minutes of laser irradiation at 33 W/cm2, demonstrating the viabilitiy of Cu2−xSe nanocrystals for photothermal therapy applications. PMID:21553924

  6. Analysis of periodically patterned metallic nanostructures for infrared absorber

    NASA Astrophysics Data System (ADS)

    Peng, Sha; Yuan, Ying; Long, Huabao; Liu, Runhan; Wei, Dong; Zhang, Xinyu; Wang, Haiwei; Xie, Changsheng

    2018-02-01

    With rapid advancement of infrared detecting technology in both military and civil domains, the photo-electronic performances of near-infrared detectors have been widely concerned. Currently, near-infrared detectors demonstrate some problems such as low sensitivity, low detectivity, and relatively small array scale. The current studies show that surface plasmons (SPs) stimulated over the surface of metallic nanostructures by incident light can be used to break the diffraction limit and thus concentrate light into sub-wavelength scale, so as to indicate a method to develop a new type of infrared absorber or detector with very large array. In this paper, we present the design and characterization of periodically patterned metallic nanostructures that combine nanometer thickness aluminum film with silicon wafer. Numerical computations show that there are some valleys caused by surface plasmons in the reflection spectrum in the infrared region, and both red shift and blue shift of the reflection spectrum were observed through changing the nanostructural parameters such as angle α and diameters D. Moreover, the strong E-field intensity is located at the sharp corner of the nano-structures.

  7. Low level light therapy by LED of different wavelength induces angiogenesis and improves ischemic wound healing.

    PubMed

    Dungel, Peter; Hartinger, Joachim; Chaudary, Sidrah; Slezak, Paul; Hofmann, Anna; Hausner, Thomas; Strassl, Martin; Wintner, Ernst; Redl, Heinz; Mittermayr, Rainer

    2014-12-01

    Low-level light therapy (LLLT) has been revealed as a potential means to improve wound healing. So far, most studies are being performed with irradiation in the red to near-infrared spectra. Recently, we showed that blue light (470 nm) can significantly influence biological systems such as nitric oxide (NO) metabolism and is able to release NO from nitrosyl-hemoglobin or mitochondrial protein complexes. Therefore, the aim of this study was to evaluate and compare the therapeutic value of blue or red light emitting diodes (LEDs) on wound healing in an ischemia disturbed rodent flap model. An abdominal flap was rendered ischemic by ligation of one epigastric bundle and subjected to LED illumination with a wavelength of 470 nm (blue, n = 8) or 629 nm (red, n = 8) each at 50 mW/cm(2) and compared to a non-treated control group (n = 8). Illumination was performed for 10 minutes on five consecutive days. LED therapy with both wavelengths significantly increased angiogenesis in the sub-epidermal layer and intramuscularly (panniculus carnosus muscle) which was associated with significantly improved tissue perfusion 7 days after the ischemic insult. Accordingly, tissue necrosis was significantly reduced and shrinkage significantly less pronounced in the LED-treated groups of both wavelengths. LED treatment of ischemia challenged tissue improved early wound healing by enhancing angiogenesis irrespective of the wavelength thus delineating this noninvasive means as a potential, cost effective tool in complicated wounds. © 2014 Wiley Periodicals, Inc.

  8. Star Formation in the DR21 Region A

    NASA Image and Video Library

    2004-04-13

    Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion). New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud. The colorful image (top panel) is a large-scale composite mosaic assembled from data collected at a variety of different wavelengths. Views at visible wavelengths appear blue, near-infrared light is depicted as green, and mid-infrared data from the InfraRed Array Camera (IRAC) aboard NASA's Spitzer Space Telescope is portrayed as red. The result is a contrast between structures seen in visible light (blue) and those observed in the infrared (yellow and red). A quick glance shows that most of the action in this image is revealed to the unique eyes of Spitzer. The image covers an area about two times that of a full moon. Each of the constituent images is shown below the large mosaic. The Digital Sky Survey (DSS) image (lower left) provides a familiar view of deep space, with stars scattered around a dark field. The reddish hue is from gas heated by foreground stars in this region. This fluorescence fades away in the near-infrared Two-Micron All-Sky Survey (2MASS) image (lower center), but other features start to appear through the obscuring clouds of dust, now increasingly transparent. Many more stars are discerned in this image because near-infrared light pierces through some of the obscuration of the interstellar dust. Note that some stars seen as very bright in the visible image are muted in the near-infrared image, whereas other stars become more prominent. Embedded nebulae revealed in the Spitzer image are only hinted at in this picture. The Spitzer image (lower right) provides a vivid contrast to the other component images, revealing star-forming complexes and large-scale structures otherwise hidden from view. The Spitzer image is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). The brightest infrared cloud near the top center corresponds to DR21, which presumably contains a cluster of newly forming stars at a distance of nearly 10,000 light-years. The red filaments stretching across the Spitzer image denote the presence of polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by surrounding interstellar radiation and become luminescent at wavelengths near 8 microns. The complex pattern of filaments is caused by an intricate combination of radiation pressure, gravity, and magnetic fields. The result is a tapestry in which winds, outflows, and turbulence move and shape the interstellar medium. http://photojournal.jpl.nasa.gov/catalog/PIA05735

  9. Star Formation in the DR21 Region (A)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] Annotated mosaic

    Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion).

    New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud.

    The colorful image (top panel) is a large-scale composite mosaic assembled from data collected at a variety of different wavelengths. Views at visible wavelengths appear blue, near-infrared light is depicted as green, and mid-infrared data from the InfraRed Array Camera (IRAC) aboard NASA's Spitzer Space Telescope is portrayed as red. The result is a contrast between structures seen in visible light (blue) and those observed in the infrared (yellow and red). A quick glance shows that most of the action in this image is revealed to the unique eyes of Spitzer. The image covers an area about two times that of a full moon.

    Each of the constituent images is shown below the large mosaic. The Digital Sky Survey (DSS) image (lower left) provides a familiar view of deep space, with stars scattered around a dark field. The reddish hue is from gas heated by foreground stars in this region. This fluorescence fades away in the near-infrared Two-Micron All-Sky Survey (2MASS) image (lower center), but other features start to appear through the obscuring clouds of dust, now increasingly transparent. Many more stars are discerned in this image because near-infrared light pierces through some of the obscuration of the interstellar dust. Note that some stars seen as very bright in the visible image are muted in the near-infrared image, whereas other stars become more prominent. Embedded nebulae revealed in the Spitzer image are only hinted at in this picture.

    The Spitzer image (lower right) provides a vivid contrast to the other component images, revealing star-forming complexes and large-scale structures otherwise hidden from view. The Spitzer image is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). The brightest infrared cloud near the top center corresponds to DR21, which presumably contains a cluster of newly forming stars at a distance of nearly 10,000 light-years.

    The red filaments stretching across the Spitzer image denote the presence of polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by surrounding interstellar radiation and become luminescent at wavelengths near 8 microns. The complex pattern of filaments is caused by an intricate combination of radiation pressure, gravity, and magnetic fields. The result is a tapestry in which winds, outflows, and turbulence move and shape the interstellar medium.

  10. Efficient perovskite/organic integrated solar cells with extended photoresponse to 930 nm and enhanced near-infrared external quantum efficiency of over 50.

    PubMed

    Guo, Qiang; Liu, Hao; Shi, Zhenzhen; Wang, Fuzhi; Zhou, Erjun; Bian, Xingming; Zhang, Bing; Alsaedi, Ahmed; Hayat, Tasawar; Tan, Zhan'ao

    2018-02-15

    Enhancing the light-harvesting activity is an effective way to improve the power conversion efficiency of solar cells. Although rapid enhancement in the PCE up to a value of 22.1% has been achieved for perovskite solar cells, only part of the sunlight, i.e., with wavelengths below 800-850 nm is utilized due to the limited bandgap of the perovskite materials, resulting in most of the near infrared light being wasted. To broaden the photoresponse of perovskite solar cells, we demonstrate an efficient perovskite/organic integrated solar cell containing both CH 3 NH 3 PbI 3 perovskite and PBDTTT-E-T:IEICO organic photoactive layers. By integrating a low band gap PBDTTT-E-T:IEICO active layer on a perovskite layer, the maximum wavelength for light harvesting of the ISC increased to 930 nm, sharply increasing the utilization of near infrared radiation. In addition, the external quantum efficiency of the integrated device exceeded 50% in the near infrared range. The MAPbI 3 /PBDTTT-E-T:IEICO ISCs show an enhanced short-circuit current density of over 24 mA cm -2 , which is the highest existing value among perovskite/organic integrated solar cells and much higher than the traditional MAPbI 3 based perovskite solar cells. The results reveal that a perovskite/organic integrated structure is a promising strategy to extend and enhance sunlight utilization for perovskite solar cells.

  11. Detector location selection based on VIP analysis in near-infrared detection of dural hematoma.

    PubMed

    Sun, Qiuming; Zhang, Yanjun; Ma, Jun; Tian, Feng; Wang, Huiquan; Liu, Dongyuan

    2018-03-01

    Detection of dural hematoma based on multi-channel near-infrared differential absorbance has the advantages of rapid and non-invasive detection. The location and number of detectors around the light source are critical for reducing the pathological characteristics of the prediction model on dural hematoma degree. Therefore, rational selection of detector numbers and their distances from the light source is very important. In this paper, a detector position screening method based on Variable Importance in the Projection (VIP) analysis is proposed. A preliminary modeling based on Partial Least Squares method (PLS) for the prediction of dural position μ a was established using light absorbance information from 30 detectors located 2.0-5.0 cm from the light source with a 0.1 cm interval. The mean relative error (MRE) of the dural position μ a prediction model was 4.08%. After VIP analysis, the number of detectors was reduced from 30 to 4 and the MRE of the dural position μ a prediction was reduced from 4.08% to 2.06% after the reduction in detector numbers. The prediction model after VIP detector screening still showed good prediction of the epidural position μ a . This study provided a new approach and important reference on the selection of detector location in near-infrared dural hematoma detection.

  12. A near-infrared SETI experiment: commissioning, data analysis, and performance results

    NASA Astrophysics Data System (ADS)

    Maire, Jérôme; Wright, Shelley A.; Dorval, Patrick; Drake, Frank D.; Duenas, Andres; Isaacson, Howard; Marcy, Geoffrey W.; Siemion, Andrew; Stone, Remington P. S.; Tallis, Melisa; Treffers, Richard R.; Werthimer, Dan

    2016-08-01

    Over the last two decades, Optical Search for Extra-Terrestrial Intelligence experiments have been conducted to search for either continuous or pulsed visible-light laser beacons that could be used for interstellar communication or energy transmission. Near-infrared offers a compelling window for signal transmission since there is a decrease in interstellar extinction and Galactic background compared to optical wavelengths. An innovative Near-InfraRed and Optical SETI (NIROSETI) instrument has been designed and constructed to take advantage of a new generation of fast (> 1 Ghz) low-noise near-infrared avalanche photodiodes to search for nanosecond pulsed near-infrared (850 - 1650 nm) pulses. The instrument was successfully installed and commissioned at the Nickel (1m) telescope at Lick Observatory in March 2015. We will describe the overall design of the instrument with a focus on methods developed for data acquisition and reduction for near-infrared SETI. Time and height analyses of the pulses produced by the detectors are performed to search for periodicity and coincidences in the signals. We will further discuss our NIROSETI survey plans.

  13. [Evaluation of Iris Morphology Viewed through Stromal Edematous Corneas by Infrared Camera].

    PubMed

    Kobayashi, Masaaki; Morishige, Naoyuki; Morita, Yukiko; Yamada, Naoyuki; Kobayashi, Motomi; Sonoda, Koh-Hei

    2016-02-01

    We reported that the application of infrared camera enables us to observe iris morphology in Peters' anomaly through edematous corneas. To observe the iris morphology in bullous keratopathy or failure grafts with an infrared camera. Eleven bullous keratopathy or failure grafts subjects (6 men and 5 women, mean age ± SD; 72.7 ± 13.0 years old) were enrolled in this study. The iris morphology was observed by applying visible light mode and near infrared light mode of infrared camera (MeibomPen). The detectability of pupil shapes, iris patterns and presence of iridectomy was evaluated. Infrared mode observation enabled us to detect the pupil shapes in 11 out of 11 cases, iris patterns in 3 out of 11 cases, and presence of iridetomy in 9 out of 11 cases although visible light mode observation could not detect any iris morphological changes. Applying infrared optics was valuable for observation of the iris morphology through stromal edematous corneas.

  14. AKARI OBSERVATION OF THE SUB-DEGREE SCALE FLUCTUATION OF THE NEAR-INFRARED BACKGROUND

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Seo, H. J.; Lee, Hyung Mok; Lee, Myung Gyoon

    2015-07-10

    We report spatial fluctuation analysis of the sky brightness in the near-infrared from observations toward the north ecliptic pole (NEP) by the AKARI at 2.4 and 3.2 μm. As a follow-up study of our previous work on the Monitor field of AKARI, we used NEP deep survey data, which covered a circular area of about 0.4 square degrees, in order to extend fluctuation analysis at angular scales up to 1000″. We found residual fluctuation over the estimated shot noise at larger angles than the angular scale of the Monitor field. The excess fluctuation of the NEP deep field smoothly connectsmore » with that of the Monitor field at angular scales of a few hundred arcseconds and extends without any significant variation to larger angular scales up to 1000″. By comparing excess fluctuations at two wavelengths, we confirm a blue spectral feature similar to the result of the Monitor field. We find that the result of this study is consistent with Spitzer Space Telescope observations at 3.6 μm. The origin of the excess fluctuation in the near-infrared background remains to be determined, but we could exclude zodiacal light, diffuse Galactic light, and unresolved faint galaxies at low redshift based on the comparison with mid- and far-infrared brightness, ground-based near-infrared images.« less

  15. [A digital micromirror device-based Hadamard transform near infrared spectrometer].

    PubMed

    Liu, Jia; Chen, Fen-Fei; Liao, Cheng-Sheng; Xu, Qian; Zeng, Li-Bo; Wu, Qiong-Shui

    2011-10-01

    A Hadamard transform near infrared spectrometer based on a digital micromirror device was constructed. The optical signal was collected by optical fiber, a grating was used for light diffraction, a digital micromirror device (DMD) was applied instead of traditional mechanical Hadamard masks for optical modulation, and an InGaAs near infrared detector was used as the optic sensor. The original spectrum was recovered by fast Hadamard transform algrithms. The advantages of the spectrometer, such as high resolution, signal-noise-ratio, stability, sensitivity and response speed were proved by experiments, which indicated that it is very suitable for oil and food-safety applications.

  16. Mid-infrared optical parametric oscillator pumped by an amplified random fiber laser

    NASA Astrophysics Data System (ADS)

    Shang, Yaping; Shen, Meili; Wang, Peng; Li, Xiao; Xu, Xiaojun

    2017-01-01

    Recently, the concept of random fiber lasers has attracted a great deal of attention for its feature to generate incoherent light without a traditional laser resonator, which is free of mode competition and insure the stationary narrow-band continuous modeless spectrum. In this Letter, we reported the first, to the best of our knowledge, optical parametric oscillator (OPO) pumped by an amplified 1070 nm random fiber laser (RFL), in order to generate stationary mid-infrared (mid-IR) laser. The experiment realized a watt-level laser output in the mid-IR range and operated relatively stable. The use of the RFL seed source allowed us to take advantage of its respective stable time-domain characteristics. The beam profile, spectrum and time-domain properties of the signal light were measured to analyze the process of frequency down-conversion process under this new pumping condition. The results suggested that the near-infrared (near-IR) signal light `inherited' good beam performances from the pump light. Those would be benefit for further develop about optical parametric process based on different pumping circumstances.

  17. Multifunctional gold nanorods for selective plasmonic photothermal therapy in pancreatic cancer cells using ultra-short pulse near-infrared laser irradiation.

    PubMed

    Patino, Tania; Mahajan, Ujjwal; Palankar, Raghavendra; Medvedev, Nikolay; Walowski, Jakob; Münzenberg, Markus; Mayerle, Julia; Delcea, Mihaela

    2015-03-12

    Gold nanorods (AuNRs) have attracted considerable attention in plasmonic photothermal therapy for cancer treatment by exploiting their selective and localized heating effect due to their unique photophysical properties. Here we describe a strategy to design a novel multifunctional platform based on AuNRs to: (i) specifically target the adenocarcinoma MUC-1 marker through the use of the EPPT-1 peptide, (ii) enhance cellular uptake through a myristoylated polyarginine peptide (MPAP) and (iii) selectively induce cell death by ultra-short near infrared laser pulses. We used a biotin-avidin based approach to conjugate EPPT-1 and MPAP to AuNRs. Dual-peptide (EPPT-1+MPAP) labelled AuNRs showed a significantly higher uptake by pancreatic ductal adenocarcinoma cells when compared to their single peptide or avidin conjugated counterparts. In addition, we selectively induced cell death by ultra-short near infrared laser pulses in small target volumes (∼1 μm3), through the creation of plasmonic nanobubbles that lead to the destruction of a local cell environment. Our approach opens new avenues for conjugation of multiple ligands on AuNRs targeting cancer cells and tumors and it is relevant for plasmonic photothermal therapy.

  18. Differential Effects of 670 and 830 nm Red near Infrared Irradiation Therapy: A Comparative Study of Optic Nerve Injury, Retinal Degeneration, Traumatic Brain and Spinal Cord Injury

    PubMed Central

    Giacci, Marcus K.; Wheeler, Lachlan; Lovett, Sarah; Dishington, Emma; Majda, Bernadette; Bartlett, Carole A.; Thornton, Emma; Harford-Wright, Elizabeth; Leonard, Anna; Vink, Robert; Harvey, Alan R.; Provis, Jan; Dunlop, Sarah A.; Fitzgerald, Melinda

    2014-01-01

    Red/near-infrared irradiation therapy (R/NIR-IT) delivered by laser or light-emitting diode (LED) has improved functional outcomes in a range of CNS injuries. However, translation of R/NIR-IT to the clinic for treatment of neurotrauma has been hampered by lack of comparative information regarding the degree of penetration of the delivered irradiation to the injury site and the optimal treatment parameters for different CNS injuries. We compared the treatment efficacy of R/NIR-IT at 670 nm and 830 nm, provided by narrow-band LED arrays adjusted to produce equal irradiance, in four in vivo rat models of CNS injury: partial optic nerve transection, light-induced retinal degeneration, traumatic brain injury (TBI) and spinal cord injury (SCI). The number of photons of 670 nm or 830 nm light reaching the SCI injury site was 6.6% and 11.3% of emitted light respectively. Treatment of rats with 670 nm R/NIR-IT following partial optic nerve transection significantly increased the number of visual responses at 7 days after injury (P≤0.05); 830 nm R/NIR-IT was partially effective. 670 nm R/NIR-IT also significantly reduced reactive species and both 670 nm and 830 nm R/NIR-IT reduced hydroxynonenal immunoreactivity (P≤0.05) in this model. Pre-treatment of light-induced retinal degeneration with 670 nm R/NIR-IT significantly reduced the number of Tunel+ cells and 8-hydroxyguanosine immunoreactivity (P≤0.05); outcomes in 830 nm R/NIR-IT treated animals were not significantly different to controls. Treatment of fluid-percussion TBI with 670 nm or 830 nm R/NIR-IT did not result in improvements in motor or sensory function or lesion size at 7 days (P>0.05). Similarly, treatment of contusive SCI with 670 nm or 830 nm R/NIR-IT did not result in significant improvements in functional recovery or reduced cyst size at 28 days (P>0.05). Outcomes from this comparative study indicate that it will be necessary to optimise delivery devices, wavelength, intensity and duration of R/NIR-IT individually for different CNS injury types. PMID:25105800

  19. Light shift from ultraviolet to near infrared light: Cerenkov luminescence with gold nanocluster - near infrared (AuNc-NIR) conjugates

    NASA Astrophysics Data System (ADS)

    Yoo, Su Woong; Mun, Hyoyoung; Oh, Gyungseok; Ryu, Youngjae; Kim, Min-Gon; Chung, Euiheon

    2015-03-01

    Cerenkov luminescence (CL) is generated when a charged particle moves faster than the speed of light in dielectric media. Recently CL imaging becomes an emerging technique with the use of radioisotopes. However, due to relatively weak blue light production and massive tissue attenuation, CL has not been applied widely. Therefore, we attempted to shift the CL emission to more near infrared (NIR) spectrum for better tissue penetration by using Cerenkov Radiation Energy Transfer (CRET). Gold nanoclusters were conjugated with NIR dye molecules (AuNc-IR820 and AuNc-ICG) to be activated with ultraviolet light. We found optimal conjugate concentrations of AuNc-NIR conjugates by spectroscopy system to generate maximal photon emission. When exposed by ultraviolet light, the emission of NIR light from the conjugates were verified. In quantitative analysis, AuNc-NIR conjugates emit brighter light signal than pure AuNc. This result implies that NIR fluorescent dyes (both IR820 and ICG) can be excited by the emission from AuNc. Following the above baseline experiment, we mixed F-18 fluorodeoxyglucose (F-18 FDG) radioisotope to the AuNc- NIR conjugates, to confirm NIR emission induced from Cerenkov radiation. Long pass filter was used to block Cerenkov luminescence and to collect the emission from AuNc-NIR conjugates. Instead of one long exposure imaging with CCD, we used multiple frame scheme to eliminate gamma radiation strike in each frame prior to combination. In summary, we obtained NIR emission light from AuNc-NIR conjugated dyes that is induced from CL. We plan to perform in vivo small animal imaging with these conjugates to assess better tissue penetration.

  20. Molecular photosensitisers for two-photon photodynamic therapy.

    PubMed

    Bolze, F; Jenni, S; Sour, A; Heitz, V

    2017-11-30

    Two-photon excitation has attracted the attention of biologists, especially after the development of two-photon excited microscopy in the nineties. Since then, new applications have rapidly emerged such as the release of biologically active molecules and photodynamic therapy (PDT) using two-photon excitation. PDT, which requires a light-activated drug (photosensitiser), is a clinically approved and minimally invasive treatment for cancer and for non-malignant diseases. This feature article focuses on the engineering of molecular two-photon photosensitisers for PDT, which should bring important benefits to the treatment, increase the treatment penetration depth with near-infrared light excitation, improve the spatial selectivity and reduce the photodamage to healthy tissues. After an overview of the two-photon absorption phenomenon and the methods to evaluate two-photon induced phototoxicity on cell cultures, the different classes of photosensitisers described in the literature are discussed. The two-photon PDT performed with historical one-photon sensitisers are briefly presented, followed by specifically engineered cyclic tetrapyrrole photosensitisers, purely organic photosensitisers and transition metal complexes. Finally, targeted two-photon photosensitisers and theranostic agents that should enhance the selectivity and efficiency of the treatment are discussed.

  1. Identification of cyanobacteriochromes detecting far-red light

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rockwell, Nathan C.; Martin, Shelley S.; Lagarias, J. Clark

    The opacity of mammalian tissue to visible light and the strong attenuation of infrared light by water at ≥900 nm have contributed to growing interest in the development of far-red and near-infrared absorbing tools for visualizing and actuating responses within live cells. Here we report the discovery of cyanobacteriochromes (CBCRs) responsive to light in this far-red window. CBCRs are linear tetrapyrrole (bilin)-based light sensors distantly related to plant phytochrome sensors. Our studies reveal far-red (λ max = 725–755 nm)/orange (λ max = 590–600 nm) and far-red/red (λ max = 615–685 nm) photoswitches that are small (<200 amino acids) and canmore » be genetically reconstituted in living cells. Phylogenetic analysis and characterization of additional CBCRs demonstrated that far-red/orange CBCRs evolved after a complex transition from green/red CBCRs known for regulating complementary chromatic acclimation. Incorporation of different bilin chromophores demonstrated that tuning mechanisms responsible for red-shifted chromophore absorption act at the A-, B-, and/ or C-rings, whereas photoisomerization occurs at the D-ring. Two such proteins exhibited detectable fluorescence extending well into the near-infrared region. In conclusion, this work extends the spectral window of CBCRs to the edge of the infrared, raising the possibility of using CBCRs in synthetic biology applications in the far-red region of the spectrum.« less

  2. Identification of cyanobacteriochromes detecting far-red light

    DOE PAGES

    Rockwell, Nathan C.; Martin, Shelley S.; Lagarias, J. Clark

    2016-06-13

    The opacity of mammalian tissue to visible light and the strong attenuation of infrared light by water at ≥900 nm have contributed to growing interest in the development of far-red and near-infrared absorbing tools for visualizing and actuating responses within live cells. Here we report the discovery of cyanobacteriochromes (CBCRs) responsive to light in this far-red window. CBCRs are linear tetrapyrrole (bilin)-based light sensors distantly related to plant phytochrome sensors. Our studies reveal far-red (λ max = 725–755 nm)/orange (λ max = 590–600 nm) and far-red/red (λ max = 615–685 nm) photoswitches that are small (<200 amino acids) and canmore » be genetically reconstituted in living cells. Phylogenetic analysis and characterization of additional CBCRs demonstrated that far-red/orange CBCRs evolved after a complex transition from green/red CBCRs known for regulating complementary chromatic acclimation. Incorporation of different bilin chromophores demonstrated that tuning mechanisms responsible for red-shifted chromophore absorption act at the A-, B-, and/ or C-rings, whereas photoisomerization occurs at the D-ring. Two such proteins exhibited detectable fluorescence extending well into the near-infrared region. In conclusion, this work extends the spectral window of CBCRs to the edge of the infrared, raising the possibility of using CBCRs in synthetic biology applications in the far-red region of the spectrum.« less

  3. HUBBLE SPIES BROWN DWARFS IN NEARBY STELLAR NURSERY

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Probing deep within a neighborhood stellar nursery, NASA's Hubble Space Telescope uncovered a swarm of newborn brown dwarfs. The orbiting observatory's near-infrared camera revealed about 50 of these objects throughout the Orion Nebula's Trapezium cluster [image at right], about 1,500 light-years from Earth. Appearing like glistening precious stones surrounding a setting of sparkling diamonds, more than 300 fledgling stars and brown dwarfs surround the brightest, most massive stars [center of picture] in Hubble's view of the Trapezium cluster's central region. All of the celestial objects in the Trapezium were born together in this hotbed of star formation. The cluster is named for the trapezoidal alignment of those central massive stars. Brown dwarfs are gaseous objects with masses so low that their cores never become hot enough to fuse hydrogen, the thermonuclear fuel stars like the Sun need to shine steadily. Instead, these gaseous objects fade and cool as they grow older. Brown dwarfs around the age of the Sun (5 billion years old) are very cool and dim, and therefore are difficult for telescopes to find. The brown dwarfs discovered in the Trapezium, however, are youngsters (1 million years old). So they're still hot and bright, and easier to see. This finding, along with observations from ground-based telescopes, is further evidence that brown dwarfs, once considered exotic objects, are nearly as abundant as stars. The image and results appear in the Sept. 20 issue of the Astrophysical Journal. The brown dwarfs are too dim to be seen in a visible-light image taken by the Hubble telescope's Wide Field and Planetary Camera 2 [picture at left]. This view also doesn't show the assemblage of infant stars seen in the near-infrared image. That's because the young stars are embedded in dense clouds of dust and gas. The Hubble telescope's near-infrared camera, the Near Infrared Camera and Multi-Object Spectrometer, penetrated those clouds to capture a view of those objects. The brown dwarfs are the faintest objects in the image. Surveying the cluster's central region, the Hubble telescope spied brown dwarfs with masses equaling 10 to 80 Jupiters. Researchers think there may be less massive brown dwarfs that are beyond the limits of Hubble's vision. The near-infrared image was taken Jan. 17, 1998. Two near-infrared filters were used to obtain information on the colors of the stars at two wavelengths (1.1 and 1.6 microns). The Trapezium picture is 1 light-year across. This composite image was made from a 'mosaic' of nine separate, but adjoining images. In this false-color image, blue corresponds to warmer, more massive stars, and red to cooler, less massive stars and brown dwarfs, and stars that are heavily obscured by dust. The visible-light data were taken in 1994 and 1995. Credits for near-infrared image: NASA; K.L. Luhman (Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass.); and G. Schneider, E. Young, G. Rieke, A. Cotera, H. Chen, M. Rieke, R. Thompson (Steward Observatory, University of Arizona, Tucson, Ariz.) Credits for visible-light picture: NASA, C.R. O'Dell and S.K. Wong (Rice University)

  4. Metal-Insulator-Semiconductor Photodetectors

    PubMed Central

    Lin, Chu-Hsuan; Liu, Chee Wee

    2010-01-01

    The major radiation of the Sun can be roughly divided into three regions: ultraviolet, visible, and infrared light. Detection in these three regions is important to human beings. The metal-insulator-semiconductor photodetector, with a simpler process than the pn-junction photodetector and a lower dark current than the MSM photodetector, has been developed for light detection in these three regions. Ideal UV photodetectors with high UV-to-visible rejection ratio could be demonstrated with III–V metal-insulator-semiconductor UV photodetectors. The visible-light detection and near-infrared optical communications have been implemented with Si and Ge metal-insulator-semiconductor photodetectors. For mid- and long-wavelength infrared detection, metal-insulator-semiconductor SiGe/Si quantum dot infrared photodetectors have been developed, and the detection spectrum covers atmospheric transmission windows. PMID:22163382

  5. A study on a portable fluorescence imaging system

    NASA Astrophysics Data System (ADS)

    Chang, Han-Chao; Wu, Wen-Hong; Chang, Chun-Li; Huang, Kuo-Cheng; Chang, Chung-Hsing; Chiu, Shang-Chen

    2011-09-01

    The fluorescent reaction is that an organism or dye, excited by UV light (200-405 nm), emits a specific frequency of light; the light is usually a visible or near infrared light (405-900 nm). During the UV light irradiation, the photosensitive agent will be induced to start the photochemical reaction. In addition, the fluorescence image can be used for fluorescence diagnosis and then photodynamic therapy can be given to dental diseases and skin cancer, which has become a useful tool to provide scientific evidence in many biomedical researches. However, most of the methods on acquiring fluorescence biology traces are still stay in primitive stage, catching by naked eyes and researcher's subjective judgment. This article presents a portable camera to obtain the fluorescence image and to make up a deficit from observer competence and subjective judgment. Furthermore, the portable camera offers the 375nm UV-LED exciting light source for user to record fluorescence image and makes the recorded image become persuasive scientific evidence. In addition, when the raising the rate between signal and noise, the signal processing module will not only amplify the fluorescence signal up to 70 %, but also decrease the noise significantly from environmental light on bill and nude mouse testing.

  6. Image-guided cancer surgery using near-infrared fluorescence

    PubMed Central

    Vahrmeijer, Alexander L.; Hutteman, Merlijn; van der Vorst, Joost R.; van de Velde, C.J.H.; Frangioni, John V.

    2013-01-01

    Paradigm shifts in surgery arise when surgeons are empowered to perform surgery faster, better, and/or less expensively. Optical imaging that exploits invisible near-infrared fluorescent light has the potential to improve cancer surgery outcomes while minimizing anesthesia time and lowering healthcare costs. Because of this, the last few years have witnessed an explosion of proof-of-concept clinical trials in the field. In this review, we introduce the concept of near-infrared fluorescence imaging for cancer surgery, review the clinical trial literature to date, outline the key issues pertaining to imaging system and contrast agent optimization, discuss limitations and leverage, and provide a framework for making the technology available for the routine care of cancer patients in the near future. PMID:23881033

  7. CuS/RGO hybrid photocatalyst for full solar spectrum photoreduction from UV/Vis to near-infrared light.

    PubMed

    Wu, Jie; Liu, Baibai; Ren, Zhenxing; Ni, Mengying; Li, Can; Gong, Yinyan; Qin, Wei; Huang, Yongli; Sun, Chang Q; Liu, Xinjuan

    2018-05-01

    To make full use of the solar energy, it remains a great challenge for semiconductor photocatalysts to harvest the full solar light spectrum from ultraviolet (UV) to visible even the near infrared (NIR) wavelength. Here we show firstly the CuS/RGO (reduced graphene oxide) hybrid photocatalyst synthesized via a microwave assisted method with full solar light (UV-Vis-NIR) active for efficient Cr(VI) reduction. The CuS/RGO displays high absorption and catalytic activity in the UV, visible and even the NIR light regions. As co-catalyst, RGO can separate and inhibit the recombination of charge carriers, consequently improving the catalytic activity. Only 1wt% RGO emersions can reduce 90% of Cr(VI) under the radiation of light over the full spectrum. Findings may provide a new strategy and substance to expand the utilization range of solar light from UV to visible even the NIR energy. Copyright © 2017. Published by Elsevier Inc.

  8. Light-Regulated Polymerization under Near-Infrared/Far-Red Irradiation Catalyzed by Bacteriochlorophyll a.

    PubMed

    Shanmugam, Sivaprakash; Xu, Jiangtao; Boyer, Cyrille

    2016-01-18

    Photoregulated polymerizations are typically conducted using high-energy (UV and blue) light, which may lead to undesired side reactions. Furthermore, as the penetration of visible light is rather limited, the range of applications with such wavelengths is likewise limited. We herein report the first living radical polymerization that can be activated and deactivated by irradiation with near-infrared (NIR) and far-red light. Bacteriochlorophyll a (Bachl a) was employed as a photoredox catalyst for photoinduced electron transfer/reversible addition-fragmentation chain transfer (PET-RAFT) polymerization. Well-defined polymers were thus synthesized within a few hours under NIR (λ=850 nm) and far-red (λ=780 nm) irradiation with excellent control over the molecular weight (M(n)/M(w)<1.25). Taking advantage of the good penetration of NIR light, we showed that the polymerization also proceeded smoothly when a translucent barrier was placed between light source and reaction vessel. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Significant and sustaining elevation of blood oxygen induced by Chinese cupping therapy as assessed by near-infrared spectroscopy.

    PubMed

    Li, Ting; Li, Yaoxian; Lin, Yu; Li, Kai

    2017-01-01

    Cupping therapy has been used in traditional Chinese medicine for thousands of years to relieve muscle pain/tendency/fatigue and to cure or reduce symbols of other diseases. However, its therapeutic effect is sparsely interpreted in the language of modern physiology. To objectively evaluate its therapeutic effect, we focused on dry cupping treatment and utilized near-infrared spectroscopy (NIRS) to assess the concentration change in oxy-hemoglobin ([HbO 2 ]), deoxy-hemoglobin ([Hb]), and blood volume in the course of cupping therapy over 13 volunteers on the infraspinatus muscle, where is usually applied for shoulder pains. Both a prominent drop in [Hb] and a significant elevation in [HbO 2 ] in the tissue surrounding the cupping site were observed during both cupping and post-treatment, manifesting the enhancement of oxygen uptake. This resulting promotion indicates potential positive therapeutic effect of cupping therapy in hemodynamics for facilitating muscular functions.

  10. Direct Bandgap Group IV Materials

    DTIC Science & Technology

    2016-01-21

    devices. In this project, we have accomplished (a) direct bandgap group IV materials of GeSn, (b) GeSn-based planar light - emitting diode operated at near...devices of planar light emitting diode , detector and laser ” 6/12/2015 PI and Co-PI information: - Name of Principal Investigators: Prof. H. H. Cheng...IV materials of GeSn, (b) GeSn-based planar light - emitting diode operated at near infrared with direct emission, and (c) the first planar

  11. Note: Three wavelengths near-infrared spectroscopy system for compensating the light absorbance by water

    NASA Astrophysics Data System (ADS)

    Bhutta, M. Raheel; Hong, Keum-Shik; Kim, Beop-Min; Hong, Melissa Jiyoun; Kim, Yun-Hee; Lee, Se-Ho

    2014-02-01

    Given that approximately 80% of blood is water, we develop a wireless functional near-infrared spectroscopy system that detects not only the concentration changes of oxy- and deoxy-hemoglobin (HbO and HbR) during mental activity but also that of water (H2O). Additionally, it implements a water-absorption correction algorithm that improves the HbO and HbR signal strengths during an arithmetic task. The system comprises a microcontroller, an optical probe, tri-wavelength light emitting diodes, photodiodes, a WiFi communication module, and a battery. System functionality was tested by means of arithmetic-task experiments performed by healthy male subjects.

  12. Note: three wavelengths near-infrared spectroscopy system for compensating the light absorbance by water.

    PubMed

    Bhutta, M Raheel; Hong, Keum-Shik; Kim, Beop-Min; Hong, Melissa Jiyoun; Kim, Yun-Hee; Lee, Se-Ho

    2014-02-01

    Given that approximately 80% of blood is water, we develop a wireless functional near-infrared spectroscopy system that detects not only the concentration changes of oxy- and deoxy-hemoglobin (HbO and HbR) during mental activity but also that of water (H2O). Additionally, it implements a water-absorption correction algorithm that improves the HbO and HbR signal strengths during an arithmetic task. The system comprises a microcontroller, an optical probe, tri-wavelength light emitting diodes, photodiodes, a WiFi communication module, and a battery. System functionality was tested by means of arithmetic-task experiments performed by healthy male subjects.

  13. Broadband Optical Active Waveguides Written by Femtosecond Laser Pulses in Lithium Fluoride

    NASA Astrophysics Data System (ADS)

    Ismael, Chiamenti; Francesca, Bonfigli; Anderson, S. L. Gomes; Rosa, Maria Montereali; Larissa, N. da Costa; Hypolito, J. Kalinowski

    2014-01-01

    Broadband waveguiding through light-emitting strips directly written in a blank lithium fluoride crystal with a femtosecond laser is reported. Light guiding was observed at several optical wavelengths, from blue, 458 nm, to near-infrared, at 1550 nm. Visible photoluminescence spectra of the optically active F2 and F3+ color centers produced by the fs laser writing process were measured. The wavelength-dependent refractive index increase was estimated to be in the order of 10-3-10-4 in the visible and near-infrared spectral intervals, which is consistent with the stable formation of point defects in LiF.

  14. Interference correction by extracting the information of interference dominant regions: Application to near-infrared spectra

    NASA Astrophysics Data System (ADS)

    Bi, Yiming; Tang, Liang; Shan, Peng; Xie, Qiong; Hu, Yong; Peng, Silong; Tan, Jie; Li, Changwen

    2014-08-01

    Interference such as baseline drift and light scattering can degrade the model predictability in multivariate analysis of near-infrared (NIR) spectra. Usually interference can be represented by an additive and a multiplicative factor. In order to eliminate these interferences, correction parameters are needed to be estimated from spectra. However, the spectra are often mixed of physical light scattering effects and chemical light absorbance effects, making it difficult for parameter estimation. Herein, a novel algorithm was proposed to find a spectral region automatically that the interesting chemical absorbance and noise are low, that is, finding an interference dominant region (IDR). Based on the definition of IDR, a two-step method was proposed to find the optimal IDR and the corresponding correction parameters estimated from IDR. Finally, the correction was performed to the full spectral range using previously obtained parameters for the calibration set and test set, respectively. The method can be applied to multi target systems with one IDR suitable for all targeted analytes. Tested on two benchmark data sets of near-infrared spectra, the performance of the proposed method provided considerable improvement compared with full spectral estimation methods and comparable with other state-of-art methods.

  15. MIRIS observation of near-infrared diffuse Galactic light

    NASA Astrophysics Data System (ADS)

    Onishi, Yosuke; Sano, Kei; Matsuura, Shuji; Jeong, Woong-Seob; Pyo, Jeonghyun; Kim, Il-Jong; Seo, Hyun Jong; Han, Wonyong; Lee, DaeHee; Moon, Bongkon; Park, Wonkee; Park, Younsik; Kim, MinGyu; Matsumoto, Toshio; Matsuhara, Hideo; Nakagawa, Takao; Tsumura, Kohji; Shirahata, Mai; Arai, Toshiaki; Ienaka, Nobuyuki

    2018-06-01

    We report near-infrared (IR) observations of high Galactic latitude clouds to investigate diffuse Galactic light (DGL), which is starlight scattered by interstellar dust grains. The observations were performed at 1.1 and 1.6 μm with a wide-field camera instrument, the Multi-purpose Infra-Red Imaging System (MIRIS) onboard the Korean satellite STSAT-3. The DGL brightness is measured by correlating the near-IR images with a far-IR 100 μm map of interstellar dust thermal emission. The wide-field observation of DGL provides the most accurate DGL measurement achieved to-date. We also find a linear correlation between optical and near-IR DGL in the MBM32 field. To study interstellar dust properties in MBM32, we adopt recent dust models with and without μm-sized very large grains and predict the DGL spectra, taking into account the reddening effect of the interstellar radiation field. The result shows that the observed color of the near-IR DGL is closer to the model spectra without very large grains. This may imply that dust growth in the observed MBM32 field is not active owing to the low density of its interstellar medium.

  16. Blue light does not impair wound healing in vitro.

    PubMed

    Masson-Meyers, Daniela Santos; Bumah, Violet Vakunseh; Enwemeka, Chukuka Samuel

    2016-07-01

    Irradiation with red or near infrared light promotes tissue repair, while treatment with blue light is known to be antimicrobial. Consequently, it is thought that infected wounds could benefit more from combined blue and red/infrared light therapy; but there is a concern that blue light may slow healing. We investigated the effect of blue 470nm light on wound healing, in terms of wound closure, total protein and collagen synthesis, growth factor and cytokines expression, in an in vitro scratch wound model. Human dermal fibroblasts were cultured for 48h until confluent. Then a linear scratch wound was created and irradiated with 3, 5, 10 or 55J/cm(2). Control plates were not irradiated. Following 24h of incubation, cells were fixed and stained for migration and fluorescence analyses and the supernatant collected for quantification of total protein, hydroxyproline, bFGF, IL-6 and IL-10. The results showed that wound closure was similar for groups treated with 3, 5 and 10J/cm(2), with a slight improvement with the 5J/cm(2) dose, and slower closure with 55J/cm(2) p<0.001). Total protein concentration increased after irradiation with 3, 5 and 10J/cm(2), reaching statistical significance at 5J/cm(2) compared to control (p<0.0001). However, hydroxyproline levels did not differ between groups. Similarly, bFGF and IL-10 concentrations did not differ between groups, but IL-6 concentration decreased progressively as fluence increased (p<0.0001). Fluorescence analysis showed viable cells regardless of irradiation fluence. We conclude that irradiation with blue light at low fluence does not impair in vitro wound healing. The significant decrease in IL-6 suggests that 470nm light is anti-inflammatory. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Use of airborne near-infrared LiDAR for determining channel cross-section characteristics and monitoring aquatic habitat in Pacific Northwest rivers: A preliminary analysis [Chapter 6

    Treesearch

    Russell N. Faux; John M. Buffington; M. German Whitley; Steve H. Lanigan; Brett B. Roper

    2009-01-01

    Aquatic habitat monitoring is being conducted by numerous organizations in many parts of the Pacific Northwest to document physical and biological conditions of stream reaches as part of legal- and policy-mandated environmental assessments. Remote sensing using discrete-return, near-infrared, airborne LiDAR (Light Detection and Ranging) and high-resolution digital...

  18. Early caries imaging and monitoring with near-infrared light.

    PubMed

    Fried, Daniel; Featherstone, John D B; Darling, Cynthia L; Jones, Robert S; Ngaotheppitak, Patara; Bühler, Christopher M

    2005-10-01

    Enamel is highly transparent in the near infrared (NIR); therefore, this region of the electromagnetic spectrum is suited ideally for the development of new optical diagnostic tools for the detection and imaging of early dental caries. This article discusses the NIR optical properties of sound and demineralized dental enamel and the potential use of polarization sensitive optical coherence tomography and NIR transillumination for the imaging of dental caries.

  19. Spatial temperature gradients guide axonal outgrowth

    PubMed Central

    Black, Bryan; Vishwakarma, Vivek; Dhakal, Kamal; Bhattarai, Samik; Pradhan, Prabhakar; Jain, Ankur; Kim, Young-tae; Mohanty, Samarendra

    2016-01-01

    Formation of neural networks during development and regeneration after injury depends on accuracy of axonal pathfinding, which is primarily believed to be influenced by chemical cues. Recently, there is growing evidence that physical cues can play crucial role in axonal guidance. However, detailed mechanism involved in such guidance cues is lacking. By using weakly-focused near-infrared continuous wave (CW) laser microbeam in the path of an advancing axon, we discovered that the beam acts as a repulsive guidance cue. Here, we report that this highly-effective at-a-distance guidance is the result of a temperature field produced by the near-infrared laser light absorption. Since light absorption by extracellular medium increases when the laser wavelength was red shifted, the threshold laser power for reliable guidance was significantly lower in the near-infrared as compared to the visible spectrum. The spatial temperature gradient caused by the near-infrared laser beam at-a-distance was found to activate temperature-sensitive membrane receptors, resulting in an influx of calcium. The repulsive guidance effect was significantly reduced when extracellular calcium was depleted or in the presence of TRPV1-antagonist. Further, direct heating using micro-heater confirmed that the axonal guidance is caused by shallow temperature-gradient, eliminating the role of any non-photothermal effects. PMID:27460512

  20. Spatial temperature gradients guide axonal outgrowth

    NASA Astrophysics Data System (ADS)

    Black, Bryan; Vishwakarma, Vivek; Dhakal, Kamal; Bhattarai, Samik; Pradhan, Prabhakar; Jain, Ankur; Kim, Young-Tae; Mohanty, Samarendra

    2016-07-01

    Formation of neural networks during development and regeneration after injury depends on accuracy of axonal pathfinding, which is primarily believed to be influenced by chemical cues. Recently, there is growing evidence that physical cues can play crucial role in axonal guidance. However, detailed mechanism involved in such guidance cues is lacking. By using weakly-focused near-infrared continuous wave (CW) laser microbeam in the path of an advancing axon, we discovered that the beam acts as a repulsive guidance cue. Here, we report that this highly-effective at-a-distance guidance is the result of a temperature field produced by the near-infrared laser light absorption. Since light absorption by extracellular medium increases when the laser wavelength was red shifted, the threshold laser power for reliable guidance was significantly lower in the near-infrared as compared to the visible spectrum. The spatial temperature gradient caused by the near-infrared laser beam at-a-distance was found to activate temperature-sensitive membrane receptors, resulting in an influx of calcium. The repulsive guidance effect was significantly reduced when extracellular calcium was depleted or in the presence of TRPV1-antagonist. Further, direct heating using micro-heater confirmed that the axonal guidance is caused by shallow temperature-gradient, eliminating the role of any non-photothermal effects.

  1. FGF1-gold nanoparticle conjugates targeting FGFR efficiently decrease cell viability upon NIR irradiation

    PubMed Central

    Szlachcic, Anna; Pala, Katarzyna; Zakrzewska, Malgorzata; Jakimowicz, Piotr; Wiedlocha, Antoni; Otlewski, Jacek

    2012-01-01

    Fibroblast growth factor receptors (FGFRs) are overexpressed in a wide variety of tumors, such as breast, bladder, and prostate cancer, and therefore they are attractive targets for different types of anticancer therapies. In this study, we designed, constructed, and characterized FGFR-targeted gold nanoconjugates suitable for infrared-induced thermal ablation (localized heating leading to cancer cell death) based on gold nanoparticles (AuNPs). We showed that a recombinant ligand of all FGFRs, human fibroblast growth factor 1 (FGF1), can be used as an agent targeting covalently bound AuNPs to cancer cells overexpressing FGFRs. To assure thermal stability, protease resistance, and prolonged half-life of the targeting protein, we employed highly stable FGF1 variant that retains the biological activities of the wild type FGF1. Novel FGF1 variant, AuNP conjugates are specifically internalized only by the cells expressing FGFRs, and they significantly reduce their viability after irradiation with near-infrared light (down to 40% of control cell viability), whereas the proliferation potential of cells lacking FGFRs is not affected. These results demonstrate the feasibility of FGF1-coated AuNPs for targeted cancer therapy. PMID:23226697

  2. Multi-watt, multi-octave, mid-infrared femtosecond source

    PubMed Central

    Hussain, Syed A.; Hartung, Alexander; Zawilski, Kevin T.; Schunemann, Peter G.; Habel, Florian; Pervak, Vladimir

    2018-01-01

    Spectroscopy in the wavelength range from 2 to 11 μm (900 to 5000 cm−1) implies a multitude of applications in fundamental physics, chemistry, as well as environmental and life sciences. The related vibrational transitions, which all infrared-active small molecules, the most common functional groups, as well as biomolecules like proteins, lipids, nucleic acids, and carbohydrates exhibit, reveal information about molecular structure and composition. However, light sources and detectors in the mid-infrared have been inferior to those in the visible or near-infrared, in terms of power, bandwidth, and sensitivity, severely limiting the performance of infrared experimental techniques. This article demonstrates the generation of femtosecond radiation with up to 5 W at 4.1 μm and 1.3 W at 8.5 μm, corresponding to an order-of-magnitude average power increase for ultrafast light sources operating at wavelengths longer than 5 μm. The presented concept is based on power-scalable near-infrared lasers emitting at a wavelength near 1 μm, which pump optical parametric amplifiers. In addition, both wavelength tunability and supercontinuum generation are reported, resulting in spectral coverage from 1.6 to 10.2 μm with power densities exceeding state-of-the-art synchrotron sources over the entire range. The flexible frequency conversion scheme is highly attractive for both up-conversion and frequency comb spectroscopy, as well as for a variety of time-domain applications. PMID:29713685

  3. Near-infrared light-controlled systems for gene transcription regulation, protein targeting and spectral multiplexing.

    PubMed

    Redchuk, Taras A; Kaberniuk, Andrii A; Verkhusha, Vladislav V

    2018-05-01

    Near-infrared (NIR, 740-780 nm) optogenetic systems are well-suited to spectral multiplexing with blue-light-controlled tools. Here, we present two protocols, one for regulation of gene transcription and another for control of protein localization, that use a NIR-responsive bacterial phytochrome BphP1-QPAS1 optogenetic pair. In the first protocol, cells are transfected with the optogenetic constructs for independently controlling gene transcription by NIR (BphP1-QPAS1) and blue (LightOn) light. The NIR and blue-light-controlled gene transcription systems show minimal spectral crosstalk and induce a 35- to 40-fold increase in reporter gene expression. In the second protocol, the BphP1-QPAS1 pair is combined with a light-oxygen-voltage-sensing (LOV) domain-based construct into a single optogenetic tool, termed iRIS. This dual-light-controllable protein localization tool allows tridirectional protein translocation among the cytoplasm, nucleus and plasma membrane. Both procedures can be performed within 3-5 d. Use of NIR light-controlled optogenetic systems should advance basic and biomedical research.

  4. Tissue phantom-based breast cancer detection using continuous near-infrared sensor

    PubMed Central

    Liu, Dan; Liu, Xin; Zhang, Yan; Wang, Qisong; Lu, Jingyang

    2016-01-01

    ABSTRACT Women's health is seriously threatened by breast cancer. Taking advantage of efficient diagnostic instruments to identify the disease is very meaningful in prolonging life. As a cheap noninvasive radiation-free technology, Near-infrared Spectroscopy is suitable for general breast cancer examination. A discrimination method of breast cancer is presented using the deference between absorption coefficients and applied to construct a blood oxygen detection device based on Modified Lambert-Beer theory. Combined with multi-wavelength multi-path near-infrared sensing technology, the proposed method can quantitatively distinguish the normal breast from the abnormal one by measuring the absorption coefficients of breast tissue and the blood oxygen saturation. An objective judgment about the breast tumor is made according to its high absorption of near-infrared light. The phantom experiment is implemented to show the presented method is able to recognize the absorption differences between phantoms and demonstrates its feasibility in the breast tumor detection. PMID:27459672

  5. Tissue phantom-based breast cancer detection using continuous near-infrared sensor.

    PubMed

    Liu, Dan; Liu, Xin; Zhang, Yan; Wang, Qisong; Lu, Jingyang

    2016-09-02

    Women's health is seriously threatened by breast cancer. Taking advantage of efficient diagnostic instruments to identify the disease is very meaningful in prolonging life. As a cheap noninvasive radiation-free technology, Near-infrared Spectroscopy is suitable for general breast cancer examination. A discrimination method of breast cancer is presented using the deference between absorption coefficients and applied to construct a blood oxygen detection device based on Modified Lambert-Beer theory. Combined with multi-wavelength multi-path near-infrared sensing technology, the proposed method can quantitatively distinguish the normal breast from the abnormal one by measuring the absorption coefficients of breast tissue and the blood oxygen saturation. An objective judgment about the breast tumor is made according to its high absorption of near-infrared light. The phantom experiment is implemented to show the presented method is able to recognize the absorption differences between phantoms and demonstrates its feasibility in the breast tumor detection.

  6. Near-infrared intraoperative imaging during resection of an anterior mediastinal soft tissue sarcoma.

    PubMed

    Predina, Jarrod D; Newton, Andrew D; Desphande, Charuhas; Singhal, Sunil

    2018-01-01

    Sarcomas are rare malignancies that are generally treated with multimodal therapy protocols incorporating complete local resection, chemotherapy and radiation. Unfortunately, even with this aggressive approach, local recurrences are common. Near-infrared intraoperative imaging is a novel technology that provides real-time visual feedback that can improve identification of disease during resection. The presented study describes utilization of a near-infrared agent (indocyanine green) during resection of an anterior mediastinal sarcoma. Real-time fluorescent feedback provided visual information that helped the surgeon during tumor localization, margin assessment and dissection from mediastinal structures. This rapidly evolving technology may prove useful in patients with primary sarcomas arising from other locations or with other mediastinal neoplasms.

  7. Visible near-infrared light scattering of single silver split-ring structure made by nanosphere lithography.

    PubMed

    Okamoto, Toshihiro; Fukuta, Tetsuya; Sato, Shuji; Haraguchi, Masanobu; Fukui, Masuo

    2011-04-11

    We succeeded in making a silver split-ring (SR) structure of approximately 130 nm in diameter on a glass substrate using a nanosphere lithography technique. The light scattering spectrum in visible near-infrared region of a single, isolated SR was measured using a microscope spectroscopy optical system. The electromagnetic field enhancement spectrum and distribution of the SR structure were simulated by the finite-difference time-domain method, and the excitation modes were clarified. The long wavelength peak in the light scattering spectra corresponded to a fundamental LC resonance mode excited by an incident electric field. It was shown that a single SR structure fabricated as abovementioned can operate as a resonator and generate a magnetic dipole. © 2011 Optical Society of America

  8. A Donor-Acceptor Conjugated Polymer with Alternating Isoindigo Derivative and Bithiophene Units for Near-Infrared Modulated Cancer Thermo-Chemotherapy.

    PubMed

    Li, Dong-Dong; Wang, Jun-Xia; Ma, Yan; Qian, Hai-Sheng; Wang, Dong; Wang, Li; Zhang, Guobing; Qiu, Longzhen; Wang, Yu-Cai; Yang, Xian-Zhu

    2016-08-03

    Conjugated polymers containing alternating donor/acceptor units have strong and sharp absorbance peaks in near-infrared (NIR) region, which could be suitable for photothermal therapy. However, these polymers as photothermal transducers are rarely reported because of their water insolubility, which limits their applications for cancer therapy. Herein, we report the donor-acceptor conjugated polymer PBIBDF-BT with alternating isoindigo derivative (BIBDF) and bithiophene (BT) units as a novel photothermal transducer, which exhibited strong near-infrared (NIR) absorbance due to its low band gap (1.52 eV). To stabilize the conjugated polymer physiological environments, we utilized an amphiphilic copolymer, poly(ethylene glycol)-block-poly(hexyl ethylene phosphate) (mPEG-b-PHEP), to stabilize PBIBDF-BT-based nanoparticles (PBIBDF-BT@NPPPE) through a single emulsion method. The obtained nanoparticles PBIBDF-BT@NPPPE showed great stability in physiological environments and excellent photostability. Moreover, the PBIBDF-BT@NPPPE exhibited high photothermal conversion efficiency, reaching 46.7%, which is relatively high compared with those of commonly used materials for photothermal therapy. Accordingly, in vivo and in vitro experiments demonstrated that PBIBDF-BT@NPPPE exhibits efficient photothermal anticancer efficacy. More importantly, PBIBDF-BT@NPPPE could simultaneously encapsulate other types of therapeutic agents though hydrophobic interactions with the PHEP core and achieve NIR-triggered intracellular drug release and a synergistic combination therapy of thermo-chemotherapy for the treatment of cancer.

  9. Simultaneous multiple wavelength upconversion in a core-shell nanoparticle for enhanced near infrared light harvesting in a dye-sensitized solar cell.

    PubMed

    Yuan, Chunze; Chen, Guanying; Li, Lin; Damasco, Jossana A; Ning, Zhijun; Xing, Hui; Zhang, Tianmu; Sun, Licheng; Zeng, Hao; Cartwright, Alexander N; Prasad, Paras N; Ågren, Hans

    2014-10-22

    The efficiency of most photovoltaic devices is severely limited by near-infrared (NIR) transmission losses. To alleviate this limitation, a new type of colloidal upconversion nanoparticles (UCNPs), hexagonal core-shell-structured β-NaYbF4:Er(3+)(2%)/NaYF4:Nd(3+)(30%), is developed and explored in this work as an NIR energy relay material for dye-sensitized solar cells (DSSCs). These UCNPs are able to harvest light energy in multiple NIR regions, and subsequently convert the absorbed energy into visible light where the DSSCs strongly absorb. The NIR-insensitive DSSCs show compelling photocurrent increases through binary upconversion under NIR light illumination either at 785 or 980 nm, substantiating efficient energy relay by these UCNPs. The overall conversion efficiency of the DSSCs was improved with the introduction of UCNPs under simulated AM 1.5 solar irradiation.

  10. [Development of a Surgical Navigation System with Beam Split and Fusion of the Visible and Near-Infrared Fluorescence].

    PubMed

    Yang, Xiaofeng; Wu, Wei; Wang, Guoan

    2015-04-01

    This paper presents a surgical optical navigation system with non-invasive, real-time, and positioning characteristics for open surgical procedure. The design was based on the principle of near-infrared fluorescence molecular imaging. The in vivo fluorescence excitation technology, multi-channel spectral camera technology and image fusion software technology were used. Visible and near-infrared light ring LED excitation source, multi-channel band pass filters, spectral camera 2 CCD optical sensor technology and computer systems were integrated, and, as a result, a new surgical optical navigation system was successfully developed. When the near-infrared fluorescence was injected, the system could display anatomical images of the tissue surface and near-infrared fluorescent functional images of surgical field simultaneously. The system can identify the lymphatic vessels, lymph node, tumor edge which doctor cannot find out with naked eye intra-operatively. Our research will guide effectively the surgeon to remove the tumor tissue to improve significantly the success rate of surgery. The technologies have obtained a national patent, with patent No. ZI. 2011 1 0292374. 1.

  11. MODIS airborne simulator visible and near-infrared calibration, 1992 ASTEX field experiment. Calibration version: ASTEX King 1.0

    NASA Technical Reports Server (NTRS)

    Arnold, G. Thomas; Fitzgerald, Michael; Grant, Patrick S.; King, Michael D.

    1994-01-01

    Calibration of the visible and near-infrared (near-IR) channels of the MODIS Airborne Simulator (MAS) is derived from observations of a calibrated light source. For the 1992 Atlantic Stratocumulus Transition Experiment (ASTEX) field deployment, the calibrated light source was the NASA Goddard 48-inch integrating hemisphere. Tests during the ASTEX deployment were conducted to calibrate the hemisphere and then the MAS. This report summarizes the ASTEX hemisphere calibration, and then describes how the MAS was calibrated from the hemisphere data. All MAS calibration measurements are presented and determination of the MAS calibration coefficients (raw counts to radiance conversion) is discussed. In addition, comparisons to an independent MAS calibration by Ames personnel using their 30-inch integrating sphere is discussed.

  12. Gold nanoflowers with mesoporous silica as "nanocarriers" for drug release and photothermal therapy in the treatment of oral cancer using near-infrared (NIR) laser light

    NASA Astrophysics Data System (ADS)

    Song, Wenzhi; Gong, Junxia; Wang, Yuqian; Zhang, Yan; Zhang, Hongmei; Zhang, Weihang; Zhang, Hu; Liu, Xin; Zhang, Tianfu; Yin, Wanzhong; Yang, Wensheng

    2016-04-01

    In this experiment, we successfully developed nanocarriers in the form of gold nanoflowers coated with two layers of silica for the purposes of drug loading and NIR (near-infrared) photothermal therapy for the treatment of oral cancer. The gold nanoflowers converted NIR laser energy into heat energy. The cores were coated with a thin silica layer (AuNFs@SiO2) to protect the gold nanoflowers from intraparticle ripening. The second layer was mesoporous silica (AuNFs@SiO2@mSiO2), which acted as a nanocarrier for anticancer drug (DOX) loads. The mean effective diameter of the nanoparticles was approximately 150-200 nm, whereas the peak absorption of the AuNFs was 684 nm. After the AuNFs were encapsulated by the silica shells, the plasmonic absorption peak of AuNFs@SiO2 and AuNFs@SiO2@mSiO2 exhibited a red shift to 718 nm. When exposed to an 808 nm NIR laser, these crystals showed an obvious photothermal conversion in the NIR region and a highly efficient release of DOX. Biocompatibility was assessed in vitro using Cell Counting Kit-8 assays, and the results showed that the nanocarriers induced no obvious cytotoxicity. This nanomaterial could be considered a new type of material that shows promising potential for photothermal-chemotherapy against malignant tumours, including those of oral cancers.

  13. Combination of Near Infrared Light-Activated Photodynamic Therapy Mediated by Indocyanine Green with Etoposide to Treat Non-Small-Cell Lung Cancer

    PubMed Central

    Luo, Ting; Zhang, Qinrong; Lu, Qing-Bin

    2017-01-01

    Indocyanine green (ICG) has been reported as a potential near-infrared (NIR) photosensitizer for photodynamic therapy (PDT) of cancer. However the application of ICG-mediated PDT is both intrinsically and physiologically limited. Here we report a combination of ICG-PDT with a chemotherapy drug etoposide (VP-16), aiming to enhance the anticancer efficacy, to circumvent limitations of PDT using ICG, and to reduce side effects of VP-16. We found in controlled in vitro cell-based assays that this combination is effective in killing non-small-cell lung cancer cells (NSCLC, A549 cell line). We also found that the combination of ICG-PDT and VP-16 exhibits strong synergy in killing non-small-cell lung cancer cells partially through inducing more DNA double-strand breaks (DSBs), while it has a much weaker synergy in killing human normal cells (GM05757). Furthermore, by studying the treatment sequence dependence and the cytotoxicity of laser-irradiated mixtures of ICG and VP-16, we found that the observed synergy involves direct/indirect reactions between ICG and VP-16. We further propose that there exists an electron transfer reaction between ICG and VP-16 under irradiation. This study therefore shows the anticancer efficacy of ICG-PDT combined with VP-16. These findings suggest that ICG-mediated PDT may be applied in combination with the chemotherapy drug VP-16 to treat some cancers, especially the non-small-cell lung cancer. PMID:28587258

  14. "Mixed-charge self-assembled monolayers" as a facile method to design pH-induced aggregation of large gold nanoparticles for near-infrared photothermal cancer therapy.

    PubMed

    Li, Huan; Liu, Xiangsheng; Huang, Nan; Ren, Kefeng; Jin, Qiao; Ji, Jian

    2014-01-01

    The acidic microenvironment of tumor tissues has proven to be one of the major differences from other normal tissues. The near-infrared (NIR) light irradiation of aggregated gold nanoparticles in a tumor acidic pH-induced manner could then provide an effect approach to treat solid tumors with the advantage of minimizing the undesired damage to normal tissues. Although it is well-known the aggregation of larger nanoparticles will result in a better NIR photothermal effect, the preparation of pH-sensitive gold nanoparticles in large sizes remains a big challenge because of their worse dispersive stability. In this paper, we introduce a facile way to endow large gold nanoparticles with tunable pH-aggregation behaviors by modifying the nanoparticle surface with mixed-charge self-assembly monolayers compromising positively and negatively charged thiol ligands. Four different size nanoparticles were used to study the general principle of tailoring the pH-induced aggregation behaviors of mixed-charge gold nanoparticles (MC-GNPs) by adjusting the surface ligand composition. With proper surface ligand composition, the MC-GNPs in four different sizes that all exhibited aggregation at tumor acidic pH were obtained. The biggest MC-GNPs showed the most encouraging aggregation-enhanced photothermal efficacy in vitro when they formed aggregates. The mixed-charge self-assembled monolayers were then proved as a facile method to design pH-induced aggregation of large gold nanoparticles for better NIR photothermal cancer therapy.

  15. Plasmons driven by single electrons in graphene nanoislands

    NASA Astrophysics Data System (ADS)

    Manjavacas, Alejandro; Thongrattanasiri, Sukosin; de Abajo, F. Javier García

    2013-04-01

    Plasmons produce large confinement and enhancement of light that enable applications as varied as cancer therapy and catalysis. Adding to these appealing properties, graphene has emerged as a robust, electrically tunable material exhibiting plasmons that strongly depend on the density of doping charges. Here we show that adding a single electron to a graphene nanoisland consisting of hundreds or thousands of atoms switches on infrared plasmons that were previously absent from the uncharged structure. Remarkably, the addition of each further electron produces a dramatic frequency shift. Plasmons in these islands are shown to be tunable down to near infrared wavelengths. These phenomena are highly sensitive to carbon edges. Specifically, armchair nanotriangles display sharp plasmons that are associated with intense near-field enhancement, as well as absorption cross-sections exceeding the geometrical area occupied by the graphene. In contrast, zigzag triangles do not support these plasmons. Our conclusions rely on realistic quantum-mechanical calculations, which are in ostensible disagreement with classical electromagnetic simulations, thus revealing the quantum nature of the plasmons. This study shows a high sensitivity of graphene nanoislands to elementary charges, therefore emphasizing their great potential for novel nano-optoelectronics applications.

  16. The Cosmic Infrared Background Experiment (CIBER): A Sounding Rocket Payload to Study the near Infrared Extragalactic Background Light

    NASA Astrophysics Data System (ADS)

    Zemcov, M.; Arai, T.; Battle, J.; Bock, J.; Cooray, A.; Hristov, V.; Keating, B.; Kim, M. G.; Lee, D. H.; Levenson, L. R.; Mason, P.; Matsumoto, T.; Matsuura, S.; Nam, U. W.; Renbarger, T.; Sullivan, I.; Suzuki, K.; Tsumura, K.; Wada, T.

    2013-08-01

    The Cosmic Infrared Background Experiment (CIBER) is a suite of four instruments designed to study the near infrared (IR) background light from above the Earth's atmosphere. The instrument package comprises two imaging telescopes designed to characterize spatial anisotropy in the extragalactic IR background caused by cosmological structure during the epoch of reionization, a low resolution spectrometer to measure the absolute spectrum of the extragalactic IR background, and a narrow band spectrometer optimized to measure the absolute brightness of the zodiacal light foreground. In this paper we describe the design and characterization of the CIBER payload. The detailed mechanical, cryogenic, and electrical design of the system are presented, including all system components common to the four instruments. We present the methods and equipment used to characterize the instruments before and after flight, and give a detailed description of CIBER's flight profile and configurations. CIBER is designed to be recoverable and has flown four times, with modifications to the payload having been informed by analysis of the first flight data. All four instruments performed to specifications during the subsequent flights, and the scientific data from these flights are currently being analyzed.

  17. THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): A SOUNDING ROCKET PAYLOAD TO STUDY THE NEAR INFRARED EXTRAGALACTIC BACKGROUND LIGHT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zemcov, M.; Bock, J.; Hristov, V.

    2013-08-15

    The Cosmic Infrared Background Experiment (CIBER) is a suite of four instruments designed to study the near infrared (IR) background light from above the Earth's atmosphere. The instrument package comprises two imaging telescopes designed to characterize spatial anisotropy in the extragalactic IR background caused by cosmological structure during the epoch of reionization, a low resolution spectrometer to measure the absolute spectrum of the extragalactic IR background, and a narrow band spectrometer optimized to measure the absolute brightness of the zodiacal light foreground. In this paper we describe the design and characterization of the CIBER payload. The detailed mechanical, cryogenic, andmore » electrical design of the system are presented, including all system components common to the four instruments. We present the methods and equipment used to characterize the instruments before and after flight, and give a detailed description of CIBER's flight profile and configurations. CIBER is designed to be recoverable and has flown four times, with modifications to the payload having been informed by analysis of the first flight data. All four instruments performed to specifications during the subsequent flights, and the scientific data from these flights are currently being analyzed.« less

  18. Sculpting a Pre-planetary Nebula with a Precessing Jet: IRAS 16342-3814

    NASA Astrophysics Data System (ADS)

    Sahai, R.; Le Mignant, D.; Sánchez Contreras, C.; Campbell, R. D.; Chaffee, F. H.

    2005-03-01

    We have imaged the bipolar pre-planetary nebula IRAS 16342-3814 with the Keck adaptive optics (AO) system in four near-infrared bands in the 1.6-4.7 μm range. The lobes, which showed smoothly varying brightness distributions in previous optical images taken with the Hubble Space Telescope, have a limb-brightened appearance in the AO images, with a remarkable corkscrew structure inscribed on the lobe walls. A well-collimated, precessing jet with a diameter <~100 AU and a precession period <~50 yr, interacting with ambient circumstellar material, is most likely responsible for the corkscrew structure and the lobes, as indicated by a detailed comparison of our observations with published numerical simulations. The very red colors of the lobes in the near-infrared, coupled with their visibility at optical wavelengths, require that at least half, but not all, of the light of the central star be trapped by a compact circumstellar dust cloud heated to ~600-700 K and reradiated in the infrared. The lobes are thus illuminated both by the infrared light from this dust cloud as well as by the optical light from the central star.

  19. Sculpting a Pre-Planetary Nebula with a Precessing Jet: IRAS 16342-3814

    NASA Technical Reports Server (NTRS)

    Sahai, R.; Le Mignant, D.; Sanchez Contreras, C.; Campbell, R. D.; Chaffee, F. H.

    2005-01-01

    We have imaged the bipolar pre-planetary nebula IRAS 16342-3814 with the Keck adaptive optics (AO) system in four near-infrared bands in the 1.6-4.7 (micro)m range. The lobes, which showed smoothly varying brightness distributions in previous optical images taken with the Hubble Space Telescope, have a limb-brightened appearance in the AO images, with a remarkable corkscrew structure inscribed on the lobe walls. A well-collimated, precessing jet with a diameter less than or approximately equal to 100 AU and a precession period less than or approximately equal to 50 yr, interacting with ambient circumstellar material, is most likely responsible for the corkscrew structure and the lobes, as indicated by a detailed comparison of our observations with published numerical simulations. The very red colors of the lobes in the near-infrared, coupled with their visibility at optical wavelengths, require that at least half, but not all, of the light of the central star be trapped by a compact circumstellar dust cloud heated to approximately 600-700 K and reradiated in the infrared. The lobes are thus illuminated both by the infrared light from this dust cloud as well as by the optical light from the central star.

  20. Novel applications of near-infrared fluorescence imaging in orthopaedic surgery (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Henderson, Eric R.; DSouza, Alisha V.; Paulsen, Keith D.; Pogue, Brian W.

    2017-02-01

    Sarcomas are cancers of the bones, muscles, nerves, and fat that require complete surgical removal for cure. The primary surgical goal therefore is to remove the tumor with a zone of normal, non-cancerous tissue surrounding the tumor, considered a `negative' surgical margin. At present, surgeons rely on radiologic imaging and visual and tactile clues to gauge cancer depth and guide surgical excision. This can result in removal of too much or too little tissue, which can lead to unnecessary removal of vital structures or incomplete cancer removal, respectively. Both results can have negative effects on ultimate patient outcome, with positive margins reported in 23% of sarcoma surgeries. Near-infrared (NIR) fluorescence probes are molecules that when stimulated with specific, known frequencies of near-infrared light will emit light of another distinct frequency. NIR light penetrates human tissue reasonably well and therefore can be used to detect the presence and location of unseen structures labeled with NIR fluorescence probes through several centimeters of tissue. Intra-operative near-infrared (NIR) fluorescence probes have been effective for this purpose in brain tumor surgery and may be applicable to sarcoma surgery. Foundational research is needed to explore the potential of this affibody probe and perfusion probes to estimate margin thickness in sarcoma surgery. In this study we will determine if sarcoma labeling using NIR fluorescence probes is superior with perfusion probes or a novel affibody probe. We will also determine whether NIR fluorescence using perfusion probes or a novel affibody probe can be correlated accurately to margin thickness.

  1. Family of BODIPY Photocages Cleaved by Single Photons of Visible/Near-Infrared Light.

    PubMed

    Peterson, Julie A; Wijesooriya, Chamari; Gehrmann, Elizabeth J; Mahoney, Kaitlyn M; Goswami, Pratik P; Albright, Toshia R; Syed, Aleem; Dutton, Andrew S; Smith, Emily A; Winter, Arthur H

    2018-06-13

    Photocages are light-sensitive chemical protecting groups that provide external control over when, where, and how much of a biological substrate is activated in cells using targeted light irradiation. Regrettably, most popular photocages (e.g., o-nitrobenzyl groups) absorb cell-damaging ultraviolet wavelengths. A challenge with achieving longer wavelength bond-breaking photochemistry is that long-wavelength-absorbing chromophores have shorter excited-state lifetimes and diminished excited-state energies. However, here we report the synthesis of a family of BODIPY-derived photocages with tunable absorptions across the visible/near-infrared that release chemical cargo under irradiation. Derivatives with appended styryl groups feature absorptions above 700 nm, yielding photocages cleaved with the highest known wavelengths of light via a direct single-photon-release mechanism. Photorelease with red light is demonstrated in living HeLa cells, Drosophila S2 cells, and bovine GM07373 cells upon ∼5 min irradiation. No cytotoxicity is observed at 20 μM photocage concentration using the trypan blue exclusion assay. Improved B-alkylated derivatives feature improved quantum efficiencies of photorelease ∼20-fold larger, on par with the popular o-nitrobenzyl photocages (εΦ = 50-100 M -1 cm -1 ), but absorbing red/near-IR light in the biological window instead of UV light.

  2. Near-infrared light-triggered thermochemotherapy of cancer using a polymer-gold nanorod conjugate

    NASA Astrophysics Data System (ADS)

    Ko, Hyewon; Son, Soyoung; Bae, Seonghwan; Kim, Joo-Hyung; Yi, Gi-Ra; Park, Jae Hyung

    2016-04-01

    A biocompatible polymer-gold nanorod (P-AuNR) conjugate was developed as a thermo-chemotherapeutic nano-sized drug carrier for cancer therapy using near-infrared (NIR) light as an external trigger. The amphiphilic polymer, poly(ethylene glycol)-block-poly(caprolactone) (PEG-b-PCL) bearing a disulfide bond, was prepared using a facile synthetic route via copper(I)-free click chemistry and covalently linked to AuNR. The chemical structures and successful conjugation of PEG-b-PCL were analyzed using 1H NMR and FT-IR. Doxorubicin (DOX), a hydrophobic anticancer drug, was effectively loaded into the hydrophobic PCL domain of P-AuNR through a simple dialysis method. P-AuNR showed longitudinal plasmon resonance absorption at the NIR region, thus generating heat under irradiation at 808 nm. Interestingly, exposure of P-AuNRs to NIR induced a structural change in the PCL block from a crystalline to an amorphous state, leading to the temporally controlled release of DOX. No significant release of DOX was observed from P-AuNRs under physiological conditions (pH 7.4), whereas the release rate of DOX was remarkably enhanced in response to NIR irradiation. In vitro cellular experiments to assess cytotoxicity and intracellular drug release behavior of DOX-P-AuNRs demonstrated that the release of DOX could be selectively regulated by NIR irradiation. Overall, DOX-P-AuNRs might have the potential to overcome the indiscriminate toxicity of free DOX.

  3. Multifunctional polymeric micelles loaded with doxorubicin and poly(dithienyl-diketopyrrolopyrrole) for near-infrared light-controlled chemo-phototherapy of cancer cells.

    PubMed

    Liu, Hui; Wang, Kai; Yang, Cangjie; Huang, Shuo; Wang, Mingfeng

    2017-09-01

    Polymeric micelles loaded with multiple therapeutic modalities are important to overcome challenges such as drug resistance and improve the therapeutic efficacy. Here we report a new polymer micellar drug carrier that integrates chemotherapy and photothermal therapy in a single platform. Specifically, a narrow bandgap poly(dithienyl-diketopyrrolopyrrole) (PDPP) polymer was encapsulated together with a model anticancer drug doxorubicin (DOX) in the hydrophobic cores of polymeric micelles formed by Pluronic F127, an amphiphilic poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer. The PDPP polymer served as an organic photothermal agent that absorbs near-infrared light (700-1000nm) and transforms into heat efficiently. The dual functional micelles co-loaded with PDPP and DOX in the hydrophobic compartment showed good colloidal stability after being stored at 4°C at least over two months, and remained visibly stable after 808-nm laser irradiation. The loaded DOX had negligible effect on the size and photothermal property of the micelles. The release of DOX from the micelles could be enhanced by the "breathing" effect of shrinking/swelling of the micelles induced by the temperature change, owing to the thermosensitive nature of the F127 polymers. Importantly, the ternary F127/PDPP/DOX micelles under 808-nm laser irradiation showed enhanced cytotoxicity against cancer cells such as HeLa cells, compared to F127 micelles containing single modality of either PDPP or DOX only. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Doxorubicin-loaded NaYF4:Yb/Tm-TiO2 inorganic photosensitizers for NIR-triggered photodynamic therapy and enhanced chemotherapy in drug-resistant breast cancers.

    PubMed

    Zeng, Leyong; Pan, Yuanwei; Tian, Ying; Wang, Xin; Ren, Wenzhi; Wang, Shouju; Lu, Guangming; Wu, Aiguo

    2015-07-01

    The combination therapy has exhibited important potential for the treatment of cancers, especially for drug-resistant cancers. In this report, bi-functional nanoprobes based on doxorubicin (DOX)-loaded NaYF4:Yb/Tm-TiO2 inorganic photosensitizers (FA-NPs-DOX) were synthesized for in vivo near infrared (NIR)-triggered inorganic photodynamic therapy (PDT) and enhanced chemotherapy to overcome the multidrug resistance (MDR) in breast cancers. Using the up-conversion luminescence (UCL) performance of NaYF4:Yb/Tm converting near-infrared (NIR) into ultraviolent (UV) lights, reactive oxygen species (ROS) were triggered from TiO2 inorganic photosensitizers for PDT under the irradiation of a 980 nm laser, by which the deep-penetration and low photo-damage could be reached. Moreover, nanocarrier delivery and folic acid (FA) targeting promoted the cellular uptake, and accelerated the release of DOX in drug-sensitive MCF-7 and resistant MCF-7/ADR cells. The toxicity assessment in vitro and in vivo revealed the good biocompatibility of the as-prepared FA-NPs-DOX nanocomposites. By the combination of enhanced chemotherapy and NIR-triggered inorganic PDT, the viability of MCF-7/ADR cells could decrease by 53.5%, and the inhibition rate of MCF-7/ADR tumors could increase up to 90.33%, compared with free DOX. Therefore, the MDR of breast cancers could be obviously overcome by enhanced chemotherapy and NIR-triggered inorganic PDT of FA-NPs-DOX nanocomposites under the excitation of a 980 nm laser. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Componential distribution analysis of food using near infrared ray image

    NASA Astrophysics Data System (ADS)

    Yamauchi, Hiroki; Kato, Kunihito; Yamamoto, Kazuhiko; Ogawa, Noriko; Ohba, Kimie

    2008-11-01

    The components of the food related to the "deliciousness" are usually evaluated by componential analysis. The component content and type of components in the food are determined by this analysis. However, componential analysis is not able to analyze measurements in detail, and the measurement is time consuming. We propose a method to measure the two-dimensional distribution of the component in food using a near infrared ray (IR) image. The advantage of our method is to be able to visualize the invisible components. Many components in food have characteristics such as absorption and reflection of light in the IR range. The component content is measured using subtraction between two wavelengths of near IR light. In this paper, we describe a method to measure the component of food using near IR image processing, and we show an application to visualize the saccharose in the pumpkin.

  6. Thermohydrogel Containing Melanin for Photothermal Cancer Therapy.

    PubMed

    Kim, Miri; Kim, Hyun Soo; Kim, Min Ah; Ryu, Hyanghwa; Jeong, Hwan-Jeong; Lee, Chang-Moon

    2017-05-01

    Melanin is an effective absorber of light and can extend to near infrared (NIR) regions. In this study, a natural melanin is presented as a photothermal therapeutic agent (PTA) because it provides a good photothermal conversion efficiency, shows biodegradability, and does not induce long-term toxicity during retention in vivo. Poloxamer solution containing melanin (Pol-Mel) does not show any precipitation and shows sol-gel transition at body temperature. After irradiation from 808 nm NIR laser at 1.5 W cm -2 for 3 min, the photothermal conversion efficiency of Pol-Mel is enough to kill cancer cells in vitro and in vivo. The tumor growth of mice bearing CT26 tumors treated with Pol-Mel injection and laser irradiation is suppressed completely without recurrence postirradiation. All these results indicate that Pol-Mel can become an attractive PTA for photothermal cancer therapy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Laser discrimination by stimulated emission of a phosphor

    NASA Technical Reports Server (NTRS)

    Mathur, V. K.; Chakrabarti, K.

    1991-01-01

    A method for discriminating sources of UV, near infrared, and far infrared laser radiation was discovered. This technology is based on the use of a single magnesium sulfide phosphor doubly doped with rare earth ions, which is thermally/optically stimulated to generate colors correlatable to the incident laser radiation. The phosphor, after initial charging by visible light, exhibits green stimulated luminescence when exposed to a near infrared source (Nd: YAG laser). On exposure to far infrared sources (CO2 laser) the phosphor emission changes to orange color. A UV laser produces both an orange red as well as green color. A device using this phosphor is useful for detecting the laser and for discriminating between the near infrared, far infrared, and UV lasers. The technology is also capable of infrared laser diode beam profiling since the radiation source leaves an imprint on the phosphor that can be photographed. Continued development of the technology offers potential for discrimination between even smaller bandwidths within the infrared spectrum, a possible aid to communication or wavemixing devices that need to rapidly identify and process optical signals.

  8. Effects of electrostimulation on the vastus medialis in the deoxygenation and the blood volume signals obtained by near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Verdaguer-Codina, Joan

    1996-12-01

    The electrotherapy field has been generated as a technique to improve the muscles of people affected by various pathologies. For this reason the electrotherapy is increasing its use as part of a treatment in muscle therapy. However there are not studies related to electrostimulation and near-IR spectroscopy. This work was designed to assess by near-IR spectroscopy the effects of electrostimulation in the vastus medialis, applying a tetanic contraction in this muscle with a compensated rectangular impulse at 100Hz, tolerating the subject 10mA of current. In the results obtained, we have not observed significant variations in the deoxygenation and blood volume signals, whereas as light change was observed comparing the calibration signals before and after to apply electrostimulation. It is postulated that electrostimulation only increases the diameter of the vessels, because the muscle doesn't do a metabolic work, and the heart rate frequency of the subject has not increased.

  9. Quantum dots in imaging, drug delivery and sensor applications

    PubMed Central

    Matea, Cristian T; Mocan, Teodora; Tabaran, Flaviu; Pop, Teodora; Mosteanu, Ofelia; Puia, Cosmin; Iancu, Cornel; Mocan, Lucian

    2017-01-01

    Quantum dots (QDs), also known as nanoscale semiconductor crystals, are nanoparticles with unique optical and electronic properties such as bright and intensive fluorescence. Since most conventional organic label dyes do not offer the near-infrared (>650 nm) emission possibility, QDs, with their tunable optical properties, have gained a lot of interest. They possess characteristics such as good chemical and photo-stability, high quantum yield and size-tunable light emission. Different types of QDs can be excited with the same light wavelength, and their narrow emission bands can be detected simultaneously for multiple assays. There is an increasing interest in the development of nano-theranostics platforms for simultaneous sensing, imaging and therapy. QDs have great potential for such applications, with notable results already published in the fields of sensors, drug delivery and biomedical imaging. This review summarizes the latest developments available in literature regarding the use of QDs for medical applications. PMID:28814860

  10. Quantum dots in imaging, drug delivery and sensor applications.

    PubMed

    Matea, Cristian T; Mocan, Teodora; Tabaran, Flaviu; Pop, Teodora; Mosteanu, Ofelia; Puia, Cosmin; Iancu, Cornel; Mocan, Lucian

    2017-01-01

    Quantum dots (QDs), also known as nanoscale semiconductor crystals, are nanoparticles with unique optical and electronic properties such as bright and intensive fluorescence. Since most conventional organic label dyes do not offer the near-infrared (>650 nm) emission possibility, QDs, with their tunable optical properties, have gained a lot of interest. They possess characteristics such as good chemical and photo-stability, high quantum yield and size-tunable light emission. Different types of QDs can be excited with the same light wavelength, and their narrow emission bands can be detected simultaneously for multiple assays. There is an increasing interest in the development of nano-theranostics platforms for simultaneous sensing, imaging and therapy. QDs have great potential for such applications, with notable results already published in the fields of sensors, drug delivery and biomedical imaging. This review summarizes the latest developments available in literature regarding the use of QDs for medical applications.

  11. Near infrared photoimmunotherapy targeting bladder cancer with a canine anti-epidermal growth factor receptor (EGFR) antibody.

    PubMed

    Nagaya, Tadanobu; Okuyama, Shuhei; Ogata, Fusa; Maruoka, Yasuhiro; Knapp, Deborah W; Karagiannis, Sophia N; Fazekas-Singer, Judit; Choyke, Peter L; LeBlanc, Amy K; Jensen-Jarolim, Erika; Kobayashi, Hisataka

    2018-04-10

    Anti-epidermal growth factor receptor (EGFR) antibody therapy is used in EGFR expressing cancers including lung, colon, head and neck, and bladder cancers, however results have been modest. Near infrared photoimmunotherapy (NIR-PIT) is a highly selective tumor treatment that employs an antibody-photo-absorber conjugate which is activated by NIR light. NIR-PIT is in clinical trials in patients with recurrent head and neck cancers using cetuximab-IR700 as the conjugate. However, its use has otherwise been restricted to mouse models. This is an effort to explore larger animal models with NIR-PIT. We describe the use of a recombinant canine anti-EGFR monoclonal antibody (mAb), can225IgG, conjugated to the photo-absorber, IR700DX, in three EGFR expressing canine transitional cell carcinoma (TCC) cell lines as a prelude to possible canine clinical studies. Can225-IR700 conjugate showed specific binding and cell-specific killing after NIR-PIT on EGFR expressing cells in vitro . In the in vivo study, can225-IR700 conjugate demonstrated accumulation of the fluorescent conjugate with high tumor-to-background ratio. Tumor-bearing mice were separated into 4 groups: (1) no treatment; (2) 100 µg of can225-IR700 i.v. only; (3) NIR light exposure only; (4) 100 µg of can225-IR700 i.v., NIR light exposure. Tumor growth was significantly inhibited by NIR-PIT treatment compared with the other groups ( p < 0.001), and significantly prolonged survival was achieved ( p < 0.001 vs. other groups) in the treatment groups. In conclusion, NIR-PIT with can225-IR700 is a promising treatment for canine EGFR-expressing cancers, including invasive transitional cell carcinoma in pet dogs, that could provide a pathway to translation to humans.

  12. Near infrared photoimmunotherapy targeting bladder cancer with a canine anti-epidermal growth factor receptor (EGFR) antibody

    PubMed Central

    Nagaya, Tadanobu; Okuyama, Shuhei; Ogata, Fusa; Maruoka, Yasuhiro; Knapp, Deborah W.; Karagiannis, Sophia N.; Fazekas-Singer, Judit; Choyke, Peter L.; LeBlanc, Amy K.; Jensen-Jarolim, Erika; Kobayashi, Hisataka

    2018-01-01

    Anti-epidermal growth factor receptor (EGFR) antibody therapy is used in EGFR expressing cancers including lung, colon, head and neck, and bladder cancers, however results have been modest. Near infrared photoimmunotherapy (NIR-PIT) is a highly selective tumor treatment that employs an antibody-photo-absorber conjugate which is activated by NIR light. NIR-PIT is in clinical trials in patients with recurrent head and neck cancers using cetuximab-IR700 as the conjugate. However, its use has otherwise been restricted to mouse models. This is an effort to explore larger animal models with NIR-PIT. We describe the use of a recombinant canine anti-EGFR monoclonal antibody (mAb), can225IgG, conjugated to the photo-absorber, IR700DX, in three EGFR expressing canine transitional cell carcinoma (TCC) cell lines as a prelude to possible canine clinical studies. Can225-IR700 conjugate showed specific binding and cell-specific killing after NIR-PIT on EGFR expressing cells in vitro. In the in vivo study, can225-IR700 conjugate demonstrated accumulation of the fluorescent conjugate with high tumor-to-background ratio. Tumor-bearing mice were separated into 4 groups: (1) no treatment; (2) 100 µg of can225-IR700 i.v. only; (3) NIR light exposure only; (4) 100 µg of can225-IR700 i.v., NIR light exposure. Tumor growth was significantly inhibited by NIR-PIT treatment compared with the other groups (p < 0.001), and significantly prolonged survival was achieved (p < 0.001 vs. other groups) in the treatment groups. In conclusion, NIR-PIT with can225-IR700 is a promising treatment for canine EGFR-expressing cancers, including invasive transitional cell carcinoma in pet dogs, that could provide a pathway to translation to humans. PMID:29721181

  13. Tantalum Sulfide Nanosheets as a Theranostic Nanoplatform for Computed Tomography Imaging-Guided Combinatorial Chemo-Photothermal Therapy.

    PubMed

    Liu, Yanlan; Ji, Xiaoyuan; Liu, Jianhua; Tong, Winnie W L; Askhatova, Diana; Shi, Jinjun

    2017-10-19

    Near-infrared (NIR)-absorbing metal-based nanomaterials have shown tremendous potential for cancer therapy, given their facile and controllable synthesis, efficient photothermal conversion, capability of spatiotemporal-controlled drug delivery, and intrinsic imaging function. Tantalum (Ta) is among the most biocompatible metals and arouses negligible adverse biological responses in either oxidized or reduced forms, and thus Ta-derived nanomaterials represent promising candidates for biomedical applications. However, Ta-based nanomaterials by themselves have not been explored for NIR-mediated photothermal ablation therapy. In this work, we report an innovative Ta-based multifunctional nanoplatform composed of biocompatible tantalum sulfide (TaS 2 ) nanosheets (NSs) for simultaneous NIR hyperthermia, drug delivery, and computed tomography (CT) imaging. The TaS 2 NSs exhibit multiple unique features including (i) efficient NIR light-to-heat conversion with a high photothermal conversion efficiency of 39%. (ii) high drug loading (177% by weight), (iii) controlled drug release triggered by NIR light and moderate acidic pH, (iv) high tumor accumulation via heat-enhanced tumor vascular permeability, (v) complete tumor ablation and negligible side effects, and (vi) comparable CT imaging contrast efficiency to the widely clinically used agent iobitridol. We expect that this multifunctional NS platform can serve as a promising candidate for imaging-guided cancer therapy and selection of cancer patients with high tumor accumulation.

  14. Carbon nanotubes as multifunctional biological transporters and near-infrared agents for selective cancer cell destruction

    NASA Astrophysics Data System (ADS)

    Nadine Wong Shi Kam,; O'Connell, Michael; Wisdom, Jeffrey A.; Dai, Hongjie

    2005-08-01

    Biological systems are known to be highly transparent to 700- to 1,100-nm near-infrared (NIR) light. It is shown here that the strong optical absorbance of single-walled carbon nanotubes (SWNTs) in this special spectral window, an intrinsic property of SWNTs, can be used for optical stimulation of nanotubes inside living cells to afford multifunctional nanotube biological transporters. For oligonucleotides transported inside living cells by nanotubes, the oligos can translocate into cell nucleus upon endosomal rupture triggered by NIR laser pulses. Continuous NIR radiation can cause cell death because of excessive local heating of SWNT in vitro. Selective cancer cell destruction can be achieved by functionalization of SWNT with a folate moiety, selective internalization of SWNTs inside cells labeled with folate receptor tumor markers, and NIR-triggered cell death, without harming receptor-free normal cells. Thus, the transporting capabilities of carbon nanotubes combined with suitable functionalization chemistry and their intrinsic optical properties can lead to new classes of novel nanomaterials for drug delivery and cancer therapy. Author contributions: N.W.S.K., M.O., and H.D. designed research; N.W.S.K., M.O., and J.A.W. performed research; N.W.S.K., M.O., and H.D. analyzed data; and N.W.S.K. and H.D. wrote the paper.This paper was submitted directly (Track II) to the PNAS office.Abbreviations: NIR, near-infrared; SWNT, single-walled carbon nanotube; AFM, atomic force microscopy; PL, phospholipid; PEG, polyethylene glycol; FA, folic acid; FR, folate receptor.

  15. Photothermal stress triggered by near infrared-irradiated carbon nanotubes promotes bone deposition in rat calvarial defects.

    PubMed

    Yanagi, Tsukasa; Kajiya, Hiroshi; Kawaguchi, Minoru; Kido, Hirofumi; Fukushima, Tadao

    2015-03-01

    The bone regenerative healing process is often prolonged, with a high risk of infection particularly in elderly and diseased patients. A reduction in healing process time usually requires mechanical stress devices, chemical cues, or laser/thermal therapies. Although these approaches have been used extensively for the reduction of bone healing time, the exact mechanisms involved in thermal stress-induced bone regeneration remain unclear. In this study, we investigated the effect of optimal hyperthermia on rat calvarial defects in vivo and on osteogenesis in vitro. Photothermal stress stimulation was carried out using a new photothermal device, composed of an alginate gel including in carbon nanotubes and their irradiator with near-infrared light. Photothermal stress (15 min at 42℃, every day), trigged by near-infrared-induced carbon nanotube, promoted bone deposition in critical-sized calvarial defects compared with nonthermal stress controls. We recently reported that our novel DNA/protamine complex scaffold induces bone regeneration in calvarial defects. In this study, photothermal stress upregulated bone deposition in DNA/protamine-engrafted calvarial defects. Furthermore, photothermal stress significantly induced expression of osteogenic related genes in a time-dependent manner, including alkaline phosphatase, osterix, and osteocalcin. This was observed in DNA/protamine cells, which were expanded from regenerated tissue engrafted into the DNA/protamine scaffold, as well as in human MG63 preosteoblasts. In summary, this novel carbon nanotube-based photothermal stress approach upregulated expression of osteogenic-related genes in preosteoblasts, resulting in promotion of mineral deposition for enhanced bone repair. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  16. Fluorescent light induces neurodegeneration in the rodent nigrostriatal system but near infrared LED light does not.

    PubMed

    Romeo, Stefania; Vitale, Flora; Viaggi, Cristina; di Marco, Stefano; Aloisi, Gabriella; Fasciani, Irene; Pardini, Carla; Pietrantoni, Ilaria; Di Paolo, Mattia; Riccitelli, Serena; Maccarone, Rita; Mattei, Claudia; Capannolo, Marta; Rossi, Mario; Capozzo, Annamaria; Corsini, Giovanni U; Scarnati, Eugenio; Lozzi, Luca; Vaglini, Francesca; Maggio, Roberto

    2017-05-01

    We investigated the effects of continuous artificial light exposure on the mouse substantia nigra (SN). A three month exposure of C57Bl/6J mice to white fluorescent light induced a 30% reduction in dopamine (DA) neurons in SN compared to controls, accompanied by a decrease of DA and its metabolites in the striatum. After six months of exposure, neurodegeneration progressed slightly, but the level of DA returned to the basal level, while the metabolites increased with respect to the control. Three month exposure to near infrared LED light (∼710nm) did not alter DA neurons in SN, nor did it decrease DA and its metabolites in the striatum. Furthermore mesencephalic cell viability, as tested by [ 3 H]DA uptake, did not change. Finally, we observed that 710nm LED light, locally conveyed in the rat SN, could modulate the firing activity of extracellular-recorded DA neurons. These data suggest that light can be detrimental or beneficial to DA neurons in SN, depending on the source and wavelength. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Endoscopic image-guided thermal therapy using targeted near infrared fluorescent gold nanorods (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Elson, Daniel S.

    2016-09-01

    We present an in vivo study of endoscopic fluorescence image-guided photothermal therapy of human oesophageal adenocarcinoma in a murine xenograft model, using intratumoural or intravenous gold nanorods functionalised with Cy5.5 and EGFR.

  18. Tunable infrared hyperbolic metamaterials with periodic indium-tin-oxide nanorods

    DOE PAGES

    Guo, Peijun; Chang, Robert P. H.; Schaller, Richard D.

    2017-07-10

    Hyperbolic metamaterials (HMMs) are artificially engineered optical media that have been used for light confinement, excited state decay rate engineering, and subwavelength imaging, due to their highly anisotropic permittivity and with it the capability of supporting high- k modes. HMMs in the infrared range can be conceived for additional applications such as free space communication, thermal engineering, and molecular sensing. Here, we demonstrate infrared HMMs comprised of periodic indium-tin-oxide nanorod arrays (ITO-NRAs). We show that the ITO-NRA based HMMs exhibit a stationary epsilon-near-pole resonance in the near-infrared regime that is insensitive to the filling ratio, and a highly tunable epsilon-near-zeromore » resonance in the mid-infrared range depending on the array periodicity. Experimental results are supported by finite-element simulations, in which the ITO-NRAs are treated both explicitly and as an effective hyperbolic media. Lastly, our work presents a low-loss HMM platform with favorable spectral tunability in the infrared range.« less

  19. Shining Light on Nanotechnology to Help Repair and Regeneration

    PubMed Central

    Gupta, Asheesh; Avci, Pinar; Sadasivam, Magesh; Chandran, Rakkiyappan; Parizotto, Nivaldo; Vecchio, Daniela; Antunes-Melo, Wanessa C; Dai, Tianhong; Chiang, Long Y.; Hamblin, Michael R.

    2012-01-01

    Phototherapy can be used in two completely different but complementary therapeutic applications. While low level laser (or light) therapy (LLLT) uses red or near-infrared light alone to reduce inflammation, pain and stimulate tissue repair and regeneration, photodynamic therapy (PDT) uses the combination of light plus non-toxic dyes (called photosensitizers) to produce reactive oxygen species that can kill infectious microorganisms and cancer cells or destroy unwanted tissue (neo-vascularization in the choroid, atherosclerotic plaques in the arteries). The recent development of nanotechnology applied to medicine (nanomedicine) has opened a new front of advancement in the field of phototherapy and has provided hope for the development of nanoscale drug delivery platforms for effective killing of pathological cells and to promote repair and regeneration. Despite the well-known beneficial effects of phototherapy and nanomaterials in producing the killing of unwanted cells and promoting repair and regeneration, there are few reports that combine all three elements i.e. phototherapy, nanotechnology and, tissue repair and regeneration. However, these areas in all possible binary combinations have been addressed by many workers. The present review aims at highlighting the combined multi-model applications of phototherapy, nanotechnology and, reparative and regeneration medicine and outlines current strategies, future applications and limitations of nanoscale-assisted phototherapy for the management of cancers, microbial infections and other diseases, and to promote tissue repair and regeneration. PMID:22951919

  20. Development of a new diffuse near-infrared food measuring

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Piao, Renguan

    2006-11-01

    Industries from agriculture to petrochemistry have found near infrared (NIR) spectroscopic analysis useful for quality control and quantitative analysis of materials and products. The general chemical, polymer chemistry, petrochemistry, agriculture, food and textile industries are currently using NIR spectroscopic methods for analysis. In this study, we developed a new sort NIR instrument for food measuring. The instrument consists of a light source, 12 filters to the prismatic part. The special part is that we use a mirror to get two beams of light. And two PbS detectors were used. One detector collected the radiation of one light beam directly and the value was set as the standard instead the standard white surface. Another light beam irradiate the sample surface, and the diffuse light was collected by another detector. The value of the two detectors was compared and the absorbency was computed. We tested the performance of the NIR instrument in determining the protein and fat content of milk powder. The calibration showed the accuracy of the instrument in practice.

  1. Nanocomplexes of Photolabile Polyelectrolyte and Upconversion Nanoparticles for Near-Infrared Light-Triggered Payload Release.

    PubMed

    Xiang, Jun; Ge, Feijie; Yu, Bing; Yan, Qiang; Shi, Feng; Zhao, Yue

    2018-06-07

    A new approach to encapsulating charged cargo molecules into a nanovector and subsequently using near-infrared (NIR) light to trigger the release is demonstrated. NIR light-responsive nanovector was prepared through electrostatic interaction-driven complexation between negatively charged silica-coated upconversion nanoparticles (UCNP@silica, 87 nm hydrodynamic diameter, polydispersity index ∼0.05) and a positively charged UV-labile polyelectrolyte bearing pendants of poly(ethylene glycol) and o-nitrobenzyl side groups; whereas charged fluorescein (FLU) was loaded through a co-complexation process. By controlling the amount of polyelectrolyte, UCNP@silica can be covered by the polymer, whereas remaining dispersed in aqueous solution. Under 980 nm laser excitation, UV light emitted by UCNP is absorbed by photolytic side groups within polyelectrolyte, which results in cleavage of o-nitrobenzyl groups and formation of carboxylic acid groups. Such NIR light-induced partial reversal of positive charge to negative charge on the polyelectrolyte layer disrupts the equilibrium among UCNP@silica, polyelectrolyte, and FLU and, consequently, leads to release of FLU molecules.

  2. Reversible near-infrared light directed reflection in a self-organized helical superstructure loaded with upconversion nanoparticles.

    PubMed

    Wang, Ling; Dong, Hao; Li, Yannian; Xue, Chenming; Sun, Ling-Dong; Yan, Chun-Hua; Li, Quan

    2014-03-26

    Adding external, dynamic control to self-organized superstructures with desired functionalities is an important leap necessary in leveraging the fascinating molecular systems for applications. Here, the new light-driven chiral molecular switch and upconversion nanoparticles, doped in a liquid crystal media, were able to self-organize into an optically tunable helical superstructure. The resulting nanoparticle impregnated helical superstructure was found to exhibit unprecedented reversible near-infrared (NIR) light-guided tunable behavior only by modulating the excitation power density of a continuous-wave NIR laser (980 nm). Upon irradiation by the NIR laser at the high power density, the reflection wavelength of the photonic superstructure red-shifted, whereas its reverse process occurred upon irradiation by the same laser but with the lower power density. Furthermore, reversible dynamic NIR-light-driven red, green, and blue reflections in a single thin film, achieved only by varying the power density of the NIR light, were for the first time demonstrated.

  3. Modification in oxidative processes in muscle tissues exposed to laser- and light-emitting diode radiation.

    PubMed

    Monich, Victor A; Bavrina, Anna P; Malinovskaya, Svetlana L

    2018-01-01

    Exposure of living tissues to high-intensity red or near-infrared light can produce the oxidative stress effects both in the target zone and adjacent ones. The protein oxidative modification (POM) products can be used as reliable and early markers of oxidative stress. The contents of modified proteins in the investigated specimens can be evaluated by the 2,4-dinitrophenylhydrazine assay (the DNPH assay). Low-intensity red light is able to decrease the activity of oxidative processes and the DNPH assay data about the POM products in the biological tissues could show both an oxidative stress level and an efficiency of physical agent protection against the oxidative processes. Two control groups of white rats were irradiated by laser light, the first control group by red light and the second one by near-infrared radiation (NIR).Two experimental groups were consequently treated with laser and red low-level light-emitting diode radiation (LED). One of them was exposed to red laser light + LED and the other to NIR + LED. The fifth group was intact. Each group included ten animals. The effect of laser light was studied by methods of protein oxidative modifications. We measured levels of both induced and spontaneous POM products by the DNPH assay. The dramatic increase in levels of POM products in the control group samples when compared with the intact group data as well as the sharp decrease in the POM products in the experimental groups treated with LED low-level light were statistically significant (p ≤ 0.05). Exposure of skeletal muscles to high-intensity red and near-infrared laser light causes oxidative stress that continues not less than 3 days. The method of measurement of POM product contents by the DNPH assay is a reliable test of an oxidative process rate. Red low-intensity LED radiation can provide rehabilitation of skeletal muscle tissues treated with high-intensity laser light.

  4. Polydopamine-coated gold nanostars for CT imaging and enhanced photothermal therapy of tumors

    NASA Astrophysics Data System (ADS)

    Li, Du; Shi, Xiangyang; Jin, Dayong

    2016-12-01

    The advancement of biocompatible nanoplatforms with dual functionalities of diagnosis and therapeutics is strongly demanded in biomedicine in recent years. In this work, we report the synthesis and characterization of polydopamine (pD)-coated gold nanostars (Au NSs) for computed tomography (CT) imaging and enhanced photothermal therapy (PTT) of tumors. Au NSs were firstly formed via a seed-mediated growth method and then stabilized with thiolated polyethyleneimine (PEI-SH), followed by deposition of pD on their surface. The formed pD-coated Au NSs (Au-PEI@pD NSs) were well characterized. We show that the Au-PEI@pD NSs are able to convert the absorbed near-infrared laser light into heat, and have strong X-ray attenuation property. Due to the co-existence of Au NSs and the pD, the light to heat conversion efficiency of the NSs can be significantly enhanced. These very interesting properties allow their uses as a powerful theranostic nanoplatform for efficient CT imaging and enhanced phtotothermal therapy of cancer cells in vitro and the xenografted tumor model in vivo. With the easy functionalization nature enabled by the coated pD shell, the developed pD-coated Au NSs may be developed as a versatile nanoplatform for targeted CT imaging and PTT of different types of cancer.

  5. NICMOS FINDS A GOLDEN RING AT THE HEART OF A GALAXY

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The revived Near Infrared Camera and Multi-Object Spectrometer (NICMOS) aboard NASA's Hubble Space Telescope has pierced the dusty disk of the 'edge-on' galaxy NGC 4013 and peered all the way to the galactic core. To the surprise of astronomers, NICMOS found a brilliant band-like structure, that may be a ring of newly formed stars [yellow band in middle photo] seen edge-on. In the visible-light view of the galaxy [top photo], the star-forming ring cannot be seen because it is embedded in dust. The most prominent feature in the visible-light image -- taken by the Wide Field and Planetary Camera 2 (WFPC2) -- is the thin, dark band of gas and dust, which is about 500 light-years thick. NICMOS enables the Hubble telescope to see in near-infrared wavelengths of light, so that it can penetrate the dust that obscures the inner hub of the galaxy. The ring-like structure spied by NICMOS encircles the core and is about 720 light-years wide, which is the typical size of most star-forming rings found in disk galaxies. The small ring is churning out stars at a torrid pace. The Milky Way Galaxy, for example, is more than 10,000 times larger than the ring. If the Milky Way produced stars at the same rate, it would be making 1,000 times more stars a year. The human eye cannot see infrared light, so colors have been assigned to correspond with near-infrared wavelengths. The blue light represents shorter near-infrared wavelengths and the red light corresponds to longer wavelengths. The ring-like structure is seen more clearly in the photo at bottom. This picture, taken with a filter sensitive to hydrogen, shows the glow of stars and gas. Astronomers used this information to calculate the rate of star formation in the ring-like structure. The extremely bright star near the center of each picture is a nearby foreground star belonging to our own Milky Way. Rings of developing stars are common in barred spiral galaxies, which have 'bars' of stars and gas slicing across their disks. The bars funnel gas to the galactic cores. But gravitational disturbances near the cores cause gas to accumulate into a lane or a ring. The gas then condenses to form stars. Because NGC 4013 is seen edge-on, astronomers don't know whether a bar of gas or some other mechanism formed the ring-like structure. NGC 4013, which looks similar to our Milky Way Galaxy, resides in the constellation Ursa Major, 55 million light-years from Earth. The middle picture is a color composite image that was made by combining photographs taken with the J-band, H-band, and Paschen-alpha filters. The bottom picture was taken with the Paschen-alpha filter. The images were taken on May 12. Credits for NICMOS images: NASA, the NICMOS Group (STScI, ESA), and the NICMOS Science Team (University of Arizona) Credits for WFPC2 image: NASA, the Hubble Heritage Team (STScI/AURA) and ESA

  6. SN 2012fr: Ultraviolet, Optical, and Near-infrared Light Curves of a Type Ia Supernova Observed within a Day of Explosion

    DOE PAGES

    Contreras, Carlos; Phillips, M. M.; Burns, Christopher R.; ...

    2018-05-18

    We present detailed ultraviolet, optical, and near-infrared light curves of the Type Ia supernova (SN) 2012fr, which exploded in the Fornax cluster member NGC 1365. These precise high-cadence light curves provide a dense coverage of the flux evolution from -12 to +140 days with respect to the epoch of B-band maximum (more » $${t}_{{B}_{\\max }}$$). Supplementary imaging at the earliest epochs reveals an initial slow and nearly linear rise in luminosity with a duration of ~2.5 days, followed by a faster rising phase that is well reproduced by an explosion model with a moderate amount of 56 Ni mixing in the ejecta. From our analysis of the light curves, we conclude that: (i) the explosion occurred < 22 hr before the first detection of the supernova, (ii) the rise time to peak bolometric (λ >1800) luminosity was 16.5 ± 0.6 days, (iii) the supernova suffered little or no host-galaxy dust reddening, (iv) the peak luminosity in both the optical and near-infrared was consistent with the bright end of normal Type Ia diversity, and (v) 0.60 ± 0.15 M ⊙ of 56Ni was synthesized in the explosion. Despite its normal luminosity, SN 2012fr displayed unusually prevalent high-velocity Ca ii and Si ii absorption features, and a nearly constant photospheric velocity of the Si ii λ6355 line at ~12,000 km s -1 that began ~5 days before $${t}_{{B}_{\\max }}$$. We also highlight some of the other peculiarities in the early phase photometry and the spectral evolution. SN 2012fr also adds to a growing number of Type Ia supernovae that are hosted by galaxies with direct Cepheid distance measurements.« less

  7. SN 2012fr: Ultraviolet, Optical, and Near-infrared Light Curves of a Type Ia Supernova Observed within a Day of Explosion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Contreras, Carlos; Phillips, M. M.; Burns, Christopher R.

    We present detailed ultraviolet, optical, and near-infrared light curves of the Type Ia supernova (SN) 2012fr, which exploded in the Fornax cluster member NGC 1365. These precise high-cadence light curves provide a dense coverage of the flux evolution from -12 to +140 days with respect to the epoch of B-band maximum (more » $${t}_{{B}_{\\max }}$$). Supplementary imaging at the earliest epochs reveals an initial slow and nearly linear rise in luminosity with a duration of ~2.5 days, followed by a faster rising phase that is well reproduced by an explosion model with a moderate amount of 56 Ni mixing in the ejecta. From our analysis of the light curves, we conclude that: (i) the explosion occurred < 22 hr before the first detection of the supernova, (ii) the rise time to peak bolometric (λ >1800) luminosity was 16.5 ± 0.6 days, (iii) the supernova suffered little or no host-galaxy dust reddening, (iv) the peak luminosity in both the optical and near-infrared was consistent with the bright end of normal Type Ia diversity, and (v) 0.60 ± 0.15 M ⊙ of 56Ni was synthesized in the explosion. Despite its normal luminosity, SN 2012fr displayed unusually prevalent high-velocity Ca ii and Si ii absorption features, and a nearly constant photospheric velocity of the Si ii λ6355 line at ~12,000 km s -1 that began ~5 days before $${t}_{{B}_{\\max }}$$. We also highlight some of the other peculiarities in the early phase photometry and the spectral evolution. SN 2012fr also adds to a growing number of Type Ia supernovae that are hosted by galaxies with direct Cepheid distance measurements.« less

  8. A Photosensitizer-Loaded DNA Origami Nanosystem for Photodynamic Therapy.

    PubMed

    Zhuang, Xiaoxi; Ma, Xiaowei; Xue, Xiangdong; Jiang, Qiao; Song, Linlin; Dai, Luru; Zhang, Chunqiu; Jin, Shubin; Yang, Keni; Ding, Baoquan; Wang, Paul C; Liang, Xing-Jie

    2016-03-22

    Photodynamic therapy (PDT) offers an alternative for cancer treatment by using ultraviolet or visible light in the presence of a photosensitizer and molecular oxygen, which can produce highly reactive oxygen species that ultimately leading to the ablation of tumor cells by multifactorial mechanisms. However, this technique is limited by the penetration depth of incident light, the hypoxic environment of solid tumors, and the vulnerability of photobleaching reduces the efficiency of many imaging agents. In this work, we reported a cellular level dual-functional imaging and PDT nanosystem BMEPC-loaded DNA origami for photodynamic therapy with high efficiency and stable photoreactive property. The carbazole derivative BMEPC is a one- and two-photon imaging agent and photosensitizer with large two-photon absorption cross section, which can be fully excited by near-infrared light, and is also capable of destroying targets under anaerobic condition by generating reactive intermediates of Type I photodynamic reactions. However, the application of BMEPC was restricted by its poor solubility in aqueous environment and its aggregation caused quenching. We observed BMEPC-loaded DNA origami effectively reduced the photobleaching of BMEPC within cells. Upon binding to DNA origami, the intramolecular rotation of BMEPC became proper restricted, which intensify fluorescence emission and radicals production when being excited. After the BMEPC-loaded DNA origami are taken up by tumor cells, upon irradiation, BMEPC could generate free radicals and be released due to DNA photocleavage as well as the following partially degradation. Apoptosis was then induced by the generation of free radicals. This functional nanosystem provides an insight into the design of photosensitizer-loaded DNA origami for effective intracellular imaging and photodynamic therapy.

  9. Low-Level Light Therapy Potentiates NPe6-mediated Photodynamic Therapy in a Human Osteosarcoma Cell Line via Increased ATP

    PubMed Central

    Tsai, Shang-Ru; Yin, Rui; Huang, Ying-Ying; Sheu, Bor-Ching; Lee, Si-Chen; Hamblin, Michael R.

    2015-01-01

    Background Low-Level Light Therapy (LLLT) is used to stimulate healing, reduce pain and inflammation, and preserve tissue from dying. LLLT has been shown to protect cells in culture from dying after various cytotoxic insults, and LLLT is known to increase the cellular ATP content. Previous studies have demonstrated that maintaining a sufficiently high ATP level is necessary for the efficient induction and execution of apoptosis steps after photodynamic therapy (PDT). Methods We asked whether LLLT would protect cells from cytotoxicity due to PDT, or conversely whether LLLT would enhance the efficacy of PDT mediated by mono-L-aspartyl chlorin(e6) (NPe6). Increased ATP could lead to enhanced cell uptake of NPe6 by the energy dependent process of endocytosis, and also to more efficient apoptosis. In this study, human osteosarcoma cell line MG-63 was subjected to 1.5 J/cm2 of 810 nm near infrared radiation (NIR) followed by addition of 10 μM NPe6 and after 2 h incubation by 1.5 J/cm2 of 652 nm red light for PDT. Results PDT combined with LLLT led to higher cell death and increased intracellular reactive oxygen species compared to PDT alone. The uptake of NPe6 was moderately increased by LLLT, and cellular ATP was increased. The mitochondrial respiratory chain inhibitor antimycin A abrogated the LLLT-induced increase in cytotoxicity. Conclusions Taken together, these results demonstrate that LLLT potentiates NPe6-mediated PDT via increased ATP synthesis and is a potentially promising strategy that could be applied in clinical PDT. PMID:25462575

  10. NASA Galaxy Mission Celebrates Sixth Anniversary

    NASA Image and Video Library

    2009-04-28

    NASA Galaxy Evolution Explorer Mission celebrates its sixth anniversary studying galaxies beyond our Milky Way through its sensitive ultraviolet telescope, the only such far-ultraviolet detector in space. The mission studies the shape, brightness, size and distance of distant galaxies across 10 billion years of cosmic history, giving scientists a wealth of data to help us better understand the origins of the universe. One such object is pictured here, the galaxy NGC598, more commonly known as M33. This image is a blend of the Galaxy Evolution Explorer's M33 image and another taken by NASA's Spitzer Space Telescope. M33, one of our closest galactic neighbors, is about 2.9 million light-years away in the constellation Triangulum, part of what's known as our Local Group of galaxies. Together, the Galaxy Evolution Explorer and Spitzer can see a broad spectrum of sky. Spitzer, for example, can detect mid-infrared radiation from dust that has absorbed young stars' ultraviolet light. That's something the Galaxy Evolution Explorer cannot see. This combined image shows in amazing detail the beautiful and complicated interlacing of the heated dust and young stars. In some regions of M33, dust gathers where there is very little far-ultraviolet light, suggesting that the young stars are obscured or that stars further away are heating the dust. In some of the outer regions of the galaxy, just the opposite is true: There are plenty of young stars and very little dust. Far-ultraviolet light from young stars glimmers blue, near-ultraviolet light from intermediate age stars glows green, near-infrared light from old stars burns yellow and orange, and dust rich in organic molecules burns red. The small blue flecks outside the spiral disk of M33 are most likely distant background galaxies. This image is a four-band composite that, in addition to the two ultraviolet bands, includes near infrared as yellow/orange and far infrared as red. http://photojournal.jpl.nasa.gov/catalog/PIA11999

  11. Near-infrared light-guided miniaturized indirect ophthalmoscopy for nonmydriatic wide-field fundus photography.

    PubMed

    Toslak, Devrim; Liu, Changgeng; Alam, Minhaj Nur; Yao, Xincheng

    2018-06-01

    A portable fundus imager is essential for emerging telemedicine screening and point-of-care examination of eye diseases. However, existing portable fundus cameras have limited field of view (FOV) and frequently require pupillary dilation. We report here a miniaturized indirect ophthalmoscopy-based nonmydriatic fundus camera with a snapshot FOV up to 67° external angle, which corresponds to a 101° eye angle. The wide-field fundus camera consists of a near-infrared light source (LS) for retinal guidance and a white LS for color retinal imaging. By incorporating digital image registration and glare elimination methods, a dual-image acquisition approach was used to achieve reflection artifact-free fundus photography.

  12. Variable field-of-view visible and near-infrared polarization compound-eye endoscope.

    PubMed

    Kagawa, K; Shogenji, R; Tanaka, E; Yamada, K; Kawahito, S; Tanida, J

    2012-01-01

    A multi-functional compound-eye endoscope enabling variable field-of-view and polarization imaging as well as extremely deep focus is presented, which is based on a compact compound-eye camera called TOMBO (thin observation module by bound optics). Fixed and movable mirrors are introduced to control the field of view. Metal-wire-grid polarizer thin film applicable to both of visible and near-infrared lights is attached to the lenses in TOMBO and light sources. Control of the field-of-view, polarization and wavelength of the illumination realizes several observation modes such as three-dimensional shape measurement, wide field-of-view, and close-up observation of the superficial tissues and structures beneath the skin.

  13. Neurophotonics: non-invasive optical techniques for monitoring brain functions

    PubMed Central

    Torricelli, Alessandro; Contini, Davide; Mora, Alberto Dalla; Pifferi, Antonio; Re, Rebecca; Zucchelli, Lucia; Caffini, Matteo; Farina, Andrea; Spinelli, Lorenzo

    2014-01-01

    Summary The aim of this review is to present the state of the art of neurophotonics, a recently founded discipline lying at the interface between optics and neuroscience. While neurophotonics also includes invasive techniques for animal studies, in this review we focus only on the non-invasive methods that use near infrared light to probe functional activity in the brain, namely the fast optical signal, diffuse correlation spectroscopy, and functional near infrared spectroscopy methods. We also present an overview of the physical principles of light propagation in biological tissues, and of the main physiological sources of signal. Finally, we discuss the open issues in models, instrumentation, data analysis and clinical approaches. PMID:25764252

  14. IRMS: Infrared Multi-Slit Spectrograph for TMT

    NASA Astrophysics Data System (ADS)

    U, Vivian; Mobasher, B.

    2014-07-01

    As one of the first-light instruments on the TMT, the IRMS is a near-infrared multi-slit spectrograph and imager designed to sample near the diffraction limit with the help of adaptive optics. Fed by the Narrow-Field Infrared Adaptive Optics Systems (NFIRAOS) on the TMT, the IRMS will provide near-infrared imaging and multi-object spectroscopy at Y, J, H, and K bands (0.9-2.5 microns) with moderate spectral resolution. With a field of view of ~2 arcmin on a side, it has a multiplex capability of up to 46 slits using a slit mask system on a cryogenic configurable slit unit. Here we present a preliminary version of the exposure time calculator for sensitivity comparison with Keck/MOSFIRE. Selected science cases are highlighted to demonstrate the need for IRMS in this upcoming thirty-meter class telescope era.

  15. Multiphoton microscopy and image guided light activated therapy using nanomaterials (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Prasad, Paras N.

    2017-02-01

    This talk will focus on design and applications of nanomaterials exhibiting strong multiphoton upconversion for multiphoton microscopy as well as for image-guided and light activated therapy .1-3 Such processes can occur by truly nonlinear optical interactions proceeding through virtual intermediate states or by stepwise coupled linear excitations through real intermediate states. Multiphoton processes in biocompatible multifunctional nanoparticles allow for 3D deep tissue imaging. In addition, they can produce in-situ photon conversion of deep tissue penetrating near IR light into a needed shorter wavelength light for photo-activated therapy at a targeted site, thus overcoming the limited penetration of UV or visible light into biological media. We are using near IR emitters such as silicon quantum dots which also exhibit strong multiphoton excitation for multiphoton microscopy. Another approach involves nonlinear nanocrystals such as ZnO which can produce four wave mixing, sum frequency generation as well as second harmonic generation to convert a deep tissue penetrating Near IR light at the targeted biological site to a desired shorter wavelength light suitable for bio imaging or activation of a therapy. We have utilized this approach to activate a photosensitizer for photodynamic therapy. Yet another type of upconversion materials is rare-earth ion doped optical nanotransformers which transform a Near IR (NIR) light from an external source by sequential single photon absorption, in situ and on demand, to a needed wavelength. Applications of these nanotransformers in multiphoton photoacoustic imaging will also be presented. An exciting direction pursued by us using these multiphoton nanoparticles, is functional imaging of brain. Simultaneously, they can effect optogenetics for regioselective stimulation of neurons for providing an effective intervention/augmentation strategy to enhance the cognitive state and lead to a foundation for futuristic vision of super human capabilities. Challenges and opportunities will be discussed.

  16. Comparisons between conventional optical imaging and parametric indirect microscopic imaging on human skin detection

    NASA Astrophysics Data System (ADS)

    Liu, Guoyan; Gao, Kun; Liu, Xuefeng; Ni, Guoqiang

    2016-10-01

    We report a new method, polarization parameters indirect microscopic imaging with a high transmission infrared light source, to detect the morphology and component of human skin. A conventional reflection microscopic system is used as the basic optical system, into which a polarization-modulation mechanics is inserted and a high transmission infrared light source is utilized. The near-field structural characteristics of human skin can be delivered by infrared waves and material coupling. According to coupling and conduction physics, changes of the optical wave parameters can be calculated and curves of the intensity of the image can be obtained. By analyzing the near-field polarization parameters in nanoscale, we can finally get the inversion images of human skin. Compared with the conventional direct optical microscope, this method can break diffraction limit and achieve a super resolution of sub-100nm. Besides, the method is more sensitive to the edges, wrinkles, boundaries and impurity particles.

  17. Near infrared harvesting dye-sensitized solar cells enabled by rare-earth upconversion materials.

    PubMed

    Li, Deyang; Ågren, Hans; Chen, Guanying

    2018-02-01

    Dye-sensitized solar cells (DSSCs) have been deemed as promising alternatives to silicon solar cells for the conversion of clean sunlight energy into electricity. A major limitation to their conversion efficiency is their inability to utilize light in the infrared (IR) spectral range, which constitutes almost half the energy of the sun's radiation. This fact has elicited motivations and endeavors to extend the response wavelength of DSSCs to the IR range. Photon upconversion through rare-earth ions constitutes one of the most promising approaches toward the goal of converting near-IR (NIR) or IR light into visible or ultraviolet light, where DSSCs typically have high sensitivity. In the present review, we summarize recent progress based on the utilization of various upconversion materials and device structures to improve the performance of dye-sensitized solar cells.

  18. Polydopamine Particle-Filled Shape-Memory Polyurethane Composites with Fast Near-Infrared Light Responsibility.

    PubMed

    Yang, Li; Tong, Rui; Wang, Zhanhua; Xia, Hesheng

    2018-03-25

    A new kind of fast near-infrared (NIR) light-responsive shape-memory polymer composites was prepared by introducing polydopamine particles (PDAPs) into commercial shape-memory polyurethane (SMPU). The toughness and strength of the polydopamine-particle-filled polyurethane composites (SMPU-PDAPs) were significantly enhanced with the addition of PDAPs due to the strong interface interaction between PDAPs and polyurethane segments. Owing to the outstanding photothermal effect of PDAPs, the composites exhibit a rapid light-responsive shape-memory process in 60 s with a PDAPs content of 0.01 wt%. Due to the excellent dispersion and convenient preparation method, PDAPs have great potential to be used as high-efficiency and environmentally friendly fillers to obtain novel photoactive functional polymer composites. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Photothermal effect of gold nanostars inkjet-printed on coated paper substrate under near-infrared irradiation

    NASA Astrophysics Data System (ADS)

    Borzenkov, Mykola; Chirico, Giuseppe; Collini, Maddalena; Määttänen, Anni; Ihalainen, Petri; Cabrini, Elisa; Dacarro, Giacomo; Pallavicini, Piersandro

    2016-04-01

    The research and development of personalized medical treatments is increasing steadily fostered by its large societal impact. The ability of non-spherical gold nanoparticles to locally and efficiently release heat when irradiated in Near Infrared (NIR) wavelength region is a promising tool for photothermal medical therapies. In the present work, stable inks containing PEGylated gold nanostars (GNS) were obtained and inkjet-printed on a pigment coated paper substrate. Significant photothermal effect of the printed patterns was observed under Near Infrared (NIR) excitation of the Localized Surface Plasmon Resonance (LSPR) of the GNS. These preliminary results support, in perspective, the application of printed GNS patterns for thermal medical treatments either by direct localized heating, or by temperature triggered drug release.

  20. The utilization of nonthermal blue (405-425 nm) and near infrared (850-890 nm) light in aesthetic dermatology and surgery-a multicenter study.

    PubMed

    Lask, Gary; Fournier, Nathalie; Trelles, Mario; Elman, Monica; Scheflan, Michael; Slatkine, Michael; Naimark, Jenny; Harth, Yoram

    2005-12-01

    A major cause of skin aging is a chronic micro-inflammation triggered by UV radiation and external pollutants. It has been demonstrated that blue light diminishes inflammatory conditions and near infrared light enhances circulation. To assess the effectiveness of a non thermal dual wavelength -- blue (405 - 420 nm) and near infrared (850 - 900 nm) -- light source in skin rejuvenation, in the reduction of the duration of post skin resurfacing erythema and in the acceleration of healing of post surgical conditions (face lift and breast augmentation). We have utilized a non contact, hand free dual wavelength light source (iClearXL and Clear100XL, Curelight Ltd) to treat over 60 patients and perform three controlled studies in four centers. Follow up duration was three months. Control group for photo-rejuvenation consisted of patients treated with Glycolic peeling and daily appliance of vitamin C Control group for post skin resurfacing erythema duration consisted of patients untreated by the light source and control group for post surgical healing consisted of patients untreated by the light source or treated by the light source on one side only. Post skin resurfacing erythema duration is reduced by 90%. The healing of post surgical conditions is substantially accelerated and discomfort is reduced. The anti aging effect of the light source includes: reduction of pore size in 90% of patients with stable results at three months follow up, enhanced skin radiance in 90% of patients with stable results at three months follow up and smoothing of fine wrinkles in 45% of patients with stable results at three months follow up. The control group showed poor results which were stable for a duration of less than one month. A non thermal, non contact / hand free light source emitting at 405-420 nm and 850-900 nm considerably enhances aesthetic and surgical aesthetic procedures without consuming user time.

  1. Near-infrared quantum dots for HER2 localization and imaging of cancer cells.

    PubMed

    Rizvi, Sarwat B; Rouhi, Sepideh; Taniguchi, Shohei; Yang, Shi Yu; Green, Mark; Keshtgar, Mo; Seifalian, Alexander M

    2014-01-01

    Quantum dots are fluorescent nanoparticles with unique photophysical properties that allow them to be used as diagnostic, therapeutic, and theranostic agents, particularly in medical and surgical oncology. Near-infrared-emitting quantum dots can be visualized in deep tissues because the biological window is transparent to these wavelengths. Their small sizes and free surface reactive groups that can be conjugated to biomolecules make them ideal probes for in vivo cancer localization, targeted chemotherapy, and image-guided cancer surgery. The human epidermal growth factor receptor 2 gene (HER2/neu) is overexpressed in 25%-30% of breast cancers. The current methods of detection for HER2 status, including immunohistochemistry and fluorescence in situ hybridization, are used ex vivo and cannot be used in vivo. In this paper, we demonstrate the application of near-infrared-emitting quantum dots for HER2 localization in fixed and live cancer cells as a first step prior to their in vivo application. Near-infrared-emitting quantum dots were characterized and their in vitro toxicity was established using three cancer cell lines, ie, HepG2, SK-BR-3 (HER2-overexpressing), and MCF7 (HER2-underexpressing). Mouse antihuman anti-HER2 monoclonal antibody was conjugated to the near-infrared-emitting quantum dots. In vitro toxicity studies showed biocompatibility of SK-BR-3 and MCF7 cell lines with near-infrared-emitting quantum dots at a concentration of 60 μg/mL after one hour and 24 hours of exposure. Near-infrared-emitting quantum dot antiHER2-antibody bioconjugates successfully localized HER2 receptors on SK-BR-3 cells. Near-infrared-emitting quantum dot bioconjugates can be used for rapid localization of HER2 receptors and can potentially be used for targeted therapy as well as image-guided surgery.

  2. Near-infrared emitting fluorescent nanocrystals-labeled natural killer cells as a platform technology for the optical imaging of immunotherapeutic cells-based cancer therapy

    NASA Astrophysics Data System (ADS)

    Taik Lim, Yong; Cho, Mi Young; Noh, Young-Woock; Chung, Jin Woong; Chung, Bong Hyun

    2009-11-01

    This study describes the development of near-infrared optical imaging technology for the monitoring of immunotherapeutic cell-based cancer therapy using natural killer (NK) cells labeled with fluorescent nanocrystals. Although NK cell-based immunotherapeutic strategies have drawn interest as potent preclinical or clinical methods of cancer therapy, there are few reports documenting the molecular imaging of NK cell-based cancer therapy, primarily due to the difficulty of labeling of NK cells with imaging probes. Human natural killer cells (NK92MI) were labeled with anti-human CD56 antibody-coated quantum dots (QD705) for fluorescence imaging. FACS analysis showed that the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 have no effect on the cell viability. The effect of anti-human CD56 antibody-coated QD705 labeling on the NK92MI cell function was investigated by measuring interferon gamma (IFN- γ) production and cytolytic activity. Finally, the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 showed a therapeutic effect similar to that of unlabeled NK92MI cells. Images of intratumorally injected NK92MI cells labeled with anti-human CD56 antibody-coated could be acquired using near-infrared optical imaging both in vivo and in vitro. This result demonstrates that the immunotherapeutic cells labeled with fluorescent nanocrystals can be a versatile platform for the effective tracking of injected therapeutic cells using optical imaging technology, which is very important in cell-based cancer therapies.

  3. Doxorubicin-loaded magnetic nanoparticle clusters for chemo-photothermal treatment of the prostate cancer cell line PC3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Weibing; Zheng, Xinmin; Shen, Shun

    2015-10-16

    In addition to the conventional cancer treatment such as radiotherapy, chemotherapy and surgical management, nanomedicine-based approaches have attracted widespread attention in recent years. In this paper, a promising nanocarrier, magnetic nanoparticle clusters (MNCs) as porous materials which provided enough room on the surface, was developed for loading chemotherapeutic agent of doxorubicin (DOX). Moreover, MNCs are a good near-infrared (NIR) photothermal mediator. Thus, MNCs have great potential both in photothermal therapy (PTT) and drug delivery for chemo-photothermal therapy of cancer. We firstly explored the destruction of prostate cancer in vitro by the combination of PTT and chemotherapy using DOX@MNCs. Upon NIR irradiationmore » at 808 nm, more cancer cells were killed when PC3 cells incubated with DOX@MNCs, owing to both MNCs-mediated photothermal ablation and cytotoxicity of light-triggered DOX release. Compared with PTT or chemotherapy alone, the chemo-photothermal therapy by DOX@MNCs showed a synergistically higher therapeutic efficacy. - Highlights: • MNCs have great potential both in photothermal therapy and drug delivery. • DOX@MNCs were used for chemo-photothermal therapy of prostate cancer cells. • DOX@MNCs showed a synergistically higher therapeutic efficacy.« less

  4. Near-infrared light-responsive liposomal contrast agent for photoacoustic imaging and drug release applications.

    PubMed

    Sivasubramanian, Kathyayini; Mathiyazhakan, Malathi; Wiraja, Christian; Upputuri, Paul Kumar; Xu, Chenjie; Pramanik, Manojit

    2017-04-01

    Photoacoustic imaging has become an emerging tool for theranostic applications. Not only does it help in

  5. Near-infrared light-responsive liposomal contrast agent for photoacoustic imaging and drug release applications

    NASA Astrophysics Data System (ADS)

    Sivasubramanian, Kathyayini; Mathiyazhakan, Malathi; Wiraja, Christian; Upputuri, Paul Kumar; Xu, Chenjie; Pramanik, Manojit

    2017-04-01

    Photoacoustic imaging has become an emerging tool for theranostic applications. Not only does it help in in vivo, noninvasive imaging of biological structures at depths but it can also be used for drug release and therapeutic applications. We explore near-infrared light-sensitive liposomes coated with gold nanostars (AuNSs) for both imaging and drug release applications using a photoacoustic imaging system. Being amphiphilic, the liposomes lipid bilayer and the aqueous core enable encapsulation of both hydrophobic and hydrophilic drugs. The AuNSs on the surface of the liposomes act as photon absorbers due to their intrinsic surface plasmon resonance. Upon excitation by laser light at specific wavelength, AuNSs facilitate rapid release of the contents encapsulated in the liposomes due to local heating and pressure wave formation (photoacoustic wave). Herein, we describe the design and optimization of the AuNSs-coated liposomes and demonstrate the release of both hydrophobic and hydrophilic model drugs (paclitaxel and calcein, respectively) through laser excitation at near-infrared wavelength. The use of AuNSs-coated liposomes as contrast agents for photoacoustic imaging is also explored with tissue phantom experiments. In comparison to blood, the AuNSs-coated liposomes have better contrast (approximately two times) at 2-cm imaging depth.

  6. Near-infrared sensitive photorefractive device using polymer dispersed liquid crystal and BSO:Ru hybrid structure.

    PubMed

    Liu, Ren Chung; Marinova, Vera; Lin, Shiuan Huei; Chen, Ming-Syuan; Lin, Yi-Hsin; Hsu, Ken Yuh

    2014-06-01

    A near-infrared sensitive hybrid device, based on a Ru-doped BSO photorefractive substrate and polymer dispersed liquid crystal (PDLC) layer, is reported. It is found that the photoexcited charge carriers generated in the BSO:Ru substrate create an optically induced space charge field, sufficient to penetrate into the PDLC layer and to re-orient the LC molecules inside the droplets. Beam-coupling measurements at the Bragg regime are performed showing prospective amplification values and high spatial resolution. The proposed structure does not require indium tin oxide (ITO) contacts and alignment layers. Such a device allows all the processes to be controlled by light, thus opening further potential for real-time image processing at the near-infrared range.

  7. Galaxies Gather at Great Distances

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Distant Galaxy Cluster Infrared Survey Poster [figure removed for brevity, see original site] [figure removed for brevity, see original site] Bird's Eye View Mosaic Bird's Eye View Mosaic with Clusters [figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] 9.1 Billion Light-Years 8.7 Billion Light-Years 8.6 Billion Light-Years

    Astronomers have discovered nearly 300 galaxy clusters and groups, including almost 100 located 8 to 10 billion light-years away, using the space-based Spitzer Space Telescope and the ground-based Mayall 4-meter telescope at Kitt Peak National Observatory in Tucson, Ariz. The new sample represents a six-fold increase in the number of known galaxy clusters and groups at such extreme distances, and will allow astronomers to systematically study massive galaxies two-thirds of the way back to the Big Bang.

    A mosaic portraying a bird's eye view of the field in which the distant clusters were found is shown at upper left. It spans a region of sky 40 times larger than that covered by the full moon as seen from Earth. Thousands of individual images from Spitzer's infrared array camera instrument were stitched together to create this mosaic. The distant clusters are marked with orange dots.

    Close-up images of three of the distant galaxy clusters are shown in the adjoining panels. The clusters appear as a concentration of red dots near the center of each image. These images reveal the galaxies as they were over 8 billion years ago, since that's how long their light took to reach Earth and Spitzer's infrared eyes.

    These pictures are false-color composites, combining ground-based optical images captured by the Mosaic-I camera on the Mayall 4-meter telescope at Kitt Peak, with infrared pictures taken by Spitzer's infrared array camera. Blue and green represent visible light at wavelengths of 0.4 microns and 0.8 microns, respectively, while red indicates infrared light at 4.5 microns.

    Kitt Peak National Observatory is part of the National Optical Astronomy Observatory in Tuscon, Ariz.

  8. Fast-response and scattering-free polymer network liquid crystals for infrared light modulators

    NASA Astrophysics Data System (ADS)

    Fan, Yun-Hsing; Lin, Yi-Hsin; Ren, Hongwen; Gauza, Sebastian; Wu, Shin-Tson

    2004-02-01

    A fast-response and scattering-free homogeneously aligned polymer network liquid crystal (PNLC) light modulator is demonstrated at λ=1.55 μm wavelength. Light scattering in the near-infrared region is suppressed by optimizing the polymer concentration such that the network domain sizes are smaller than the wavelength. The strong polymer network anchoring assists LC to relax back quickly as the electric field is removed. As a result, the PNLC response time is ˜250× faster than that of the E44 LC mixture except that the threshold voltage is increased by ˜25×.

  9. Efficacy of a near-infrared light device in pediatric intravenous cannulation: a randomized controlled trial.

    PubMed

    Perry, Andrew M; Caviness, Alison Chantal; Hsu, Deborah C

    2011-01-01

    To determine whether the use of a near-infrared light venipuncture aid (VeinViewer; Luminetx Corporation, Memphis, Tenn) would improve the rate of successful first-attempt placement of intravenous (IV) catheters in a high-volume pediatric emergency department (ED). Patients younger than 20 years with standard clinical indications for IV access were randomized to have IV placement by ED nurses (in 3 groups stratified by 5-year blocks of nursing experience) using traditional methods (standard group) or with the aid of the near-infrared light source (device group). If a vein could not be cannulated after 3 attempts, patients crossed over from one study arm to the other, and study nurses attempted placement with the alternative technique. The primary end point was first-attempt success rate for IV catheter placement. After completion of patient enrollment, a questionnaire was completed by study nurses as a qualitative assessment of the device. A total of 123 patients (median age, 3 years) were included in the study: 62 in the standard group and 61 in the device group. There was no significant difference in first-attempt success rate between the standard (79.0%, 95% confidence interval [CI], 66.8%-88.3%) and device (72.1%, 95% CI, 59.2%-82.9%) groups. Of the 19 study nurses, 14 completed the questionnaire of whom 70% expressed neutral or unfavorable assessments of the device in nondehydrated patients without chronic underlying medical conditions and 90% found the device a helpful tool for patients in whom IV access was difficult. First-attempt success rate for IV placement was nonsignificantly higher without than with the assistance of a near-infrared light device in a high-volume pediatric ED. Nurses placing IVs did report several benefits to use of the device with specific patient groups, and future research should be conducted to demonstrate the role of the device in these patients.

  10. Significant and sustaining elevation of blood oxygen induced by Chinese cupping therapy as assessed by near-infrared spectroscopy

    PubMed Central

    Li, Ting; Li, Yaoxian; Lin, Yu; Li, Kai

    2016-01-01

    Cupping therapy has been used in traditional Chinese medicine for thousands of years to relieve muscle pain/tendency/fatigue and to cure or reduce symbols of other diseases. However, its therapeutic effect is sparsely interpreted in the language of modern physiology. To objectively evaluate its therapeutic effect, we focused on dry cupping treatment and utilized near-infrared spectroscopy (NIRS) to assess the concentration change in oxy-hemoglobin ([HbO2]), deoxy-hemoglobin ([Hb]), and blood volume in the course of cupping therapy over 13 volunteers on the infraspinatus muscle, where is usually applied for shoulder pains. Both a prominent drop in [Hb] and a significant elevation in [HbO2] in the tissue surrounding the cupping site were observed during both cupping and post-treatment, manifesting the enhancement of oxygen uptake. This resulting promotion indicates potential positive therapeutic effect of cupping therapy in hemodynamics for facilitating muscular functions. PMID:28101413

  11. QUASAR PG1115+080 AND GRAVITATIONAL LENS

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Left: The light from the single quasar PG 1115+080 is split and distorted in this infrared image. PG 1115+080 is at a distance of about 8 billion light years in the constellation Leo, and it is viewed through an elliptical galaxy lens at a distance of 3 billion light years. The NICMOS frame is taken at a wavelength of 1.6 microns and it shows the four images of the quasar (the two on the left are nearly merging) surrounding the galaxy that causes the light to be lensed. The quasar is a variable light source and the light in each image travels a different path to reach the Earth. The time delay of the variations allows the distance scale to be measured directly. The linear streaks on the image are diffraction artifacts in the NICMOS instrument (NASA/Space Telescope Science Institute). Right: In this NICMOS image, the four quasar images and the lens galaxy have been subtracted, revealing a nearly complete ring of infrared light. This ring is the stretched and amplified starlight of the galaxy that contains the quasar, some 8 billion light years away. (NASA/Space Telescope Science Institute). Credit: Christopher D. Impey (University of Arizona)

  12. Optical design and fabrication of palm/fingerprint uniform illumination system with a high-power near-infrared light-emitting diode.

    PubMed

    Jing, Lei; Wang, Yao; Zhao, Huifu; Ke, Hongliang; Wang, Xiaoxun; Gao, Qun

    2017-06-10

    In order to meet the requirements of uniform illumination for optical palm/fingerprint instruments and overcome the shortcomings of the poor uniform illumination on the working plane of the optical palm/fingerprint prism, a novel secondary optical lens with a free-form surface, compact structure, and high uniformity is presented in this paper. The design of the secondary optical lens is based on emission properties of the near-infrared light-emitting diode (LED) and basic principles of non-imaging optics, especially considering the impact of the thickness of the prism in the design. Through the numerical solution of Snell's law in geometric optics, we obtain the profile of the free-form surface of the lens. Using the optical software TracePro, we trace and simulate the illumination system. The results show that the uniformity is 89.8% on the working plane of the prism, and the test results show that the actual uniformity reaches 85.7% in the experiment, which provides an effective way for realizing a highly uniform illumination system with high-power near-infrared LED.

  13. Near-infrared transillumination photography of intraocular tumours.

    PubMed

    Krohn, Jørgen; Ulltang, Erlend; Kjersem, Bård

    2013-10-01

    To present a technique for near-infrared transillumination imaging of intraocular tumours based on the modifications of a conventional digital slit lamp camera system. The Haag-Streit Photo-Slit Lamp BX 900 (Haag-Streit AG) was used for transillumination photography by gently pressing the tip of the background illumination cable against the surface of the patient's eye. Thus the light from the flash unit was transmitted into the eye, leading to improved illumination and image resolution. The modification for near-infrared photography was done by replacing the original camera with a Canon EOS 30D (Canon Inc) converted by Advanced Camera Services Ltd. In this camera, the infrared blocking filter was exchanged for a 720 nm long-pass filter, so that the near-infrared part of the spectrum was recorded by the sensor. The technique was applied in eight patients: three with anterior choroidal melanoma, three with ciliary body melanoma and two with ocular pigment alterations. The good diagnostic quality of the photographs made it possible to evaluate the exact location and extent of the lesions in relation to pigmented intraocular landmarks such as the ora serrata and ciliary body. The photographic procedure did not lead to any complications. We recommend near-infrared transillumination photography as a supplementary diagnostic tool for the evaluation and documentation of anteriorly located intraocular tumours.

  14. Difference Verification of Cheek Subcutaneous Fat Thickness of Male and Female Using Near Infrared Ray Spectral Characteristic Simulation of Cheek

    NASA Astrophysics Data System (ADS)

    Nishino, Satoshi; Yasuda, Shun

    The near infrared ray spectral characteristic of a person’s cheeks was simulated in this paper, and it was confirmed that the spectral characteristic of the cheeks part by the near infrared rays was detected at the subcutaneous fat under 2mm of the skin. Therefore, subcutaneous fat has a great influence at the near infrared ray spectral characteristic. Concretely, when subcutaneous fat thickness is thick, the absorbance falls down, and the spectral characteristic around 1200nm is the same for an acute angle, and becomes the spectral characteristic of the female. On the other hand, increasing the water content to simulate the increase in the thickness of the subcutaneous fat, the light absorbance rises, and the acute angle of the spectral characteristic around 1200nm disappears. The 1200nm characteristic becomes that of the male’s spectral characteristic which shows a rounded form. From the discussion above, it could be verified that a difference in the subcutaneous fat thickness is the factor of the difference in the near infrared ray spectral characteristics between that of a male and female cheek.

  15. Effect of NASA light-emitting diode irradiation on molecular changes for wound healing in diabetic mice.

    PubMed

    Whelan, Harry T; Buchmann, Ellen V; Dhokalia, Apsara; Kane, Mary P; Whelan, Noel T; Wong-Riley, Margaret T T; Eells, Janis T; Gould, Lisa J; Hammamieh, Rasha; Das, Rina; Jett, Marti

    2003-04-01

    The purpose of this study was to assess the changes in gene expression of near-infrared light therapy in a model of impaired wound healing. Light-Emitting Diodes (LED), originally developed for NASA plant growth experiments in space, show promise for delivering light deep into tissues of the body to promote wound healing and human tissue growth. In this paper we present the effects of LED treatment on wounds in a genetically diabetic mouse model. Polyvinyl acetal (PVA) sponges were subcutaneously implanted in the dorsum of BKS.Cg-m +/+ Lepr(db) mice. LED treatments were given once daily, and at the sacrifice day, the sponges, incision line and skin over the sponges were harvested and used for RNA extraction. The RNA was subsequently analyzed by cDNA array. Our studies have revealed certain tissue regenerating genes that were significantly upregulated upon LED treatment when compared to the untreated sample. Integrins, laminin, gap junction proteins, and kinesin superfamily motor proteins are some of the genes involved during regeneration process. These are some of the genes that were identified upon gene array experiments with RNA isolated from sponges from the wound site in mouse with LED treatment. We believe that the use of NASA light-emitting diodes (LED) for light therapy will greatly enhance the natural wound healing process, and more quickly return the patient to a preinjury/illness level of activity. This work is supported and managed through the Defense Advanced Research Projects Agency (DARPA) and NASA Marshall Space Flight Center-SBIR Program.

  16. Dissociation of β-Sheet Stacking of Amyloid β Fibrils by Irradiation of Intense, Short-Pulsed Mid-infrared Laser.

    PubMed

    Kawasaki, Takayasu; Yaji, Toyonari; Ohta, Toshiaki; Tsukiyama, Koichi; Nakamura, Kazuhiro

    2018-02-05

    Structure of amyloid β (Aβ) fibrils is rigidly stacked by β-sheet conformation, and the fibril state of Aβ is profoundly related to pathogenesis of Alzheimer's disease (AD). Although mid-infrared light has been used for various biological researches, it has not yet been known whether the infrared light changes the fibril structure of Aβ. In this study, we tested the effect of irradiation of intense mid-infrared light from a free-electron laser (FEL) targeting the amide bond on the reduction of β-sheet content in Aβ fibrils. The FEL reduced entire contents of proteins exhibiting β-sheet structure in brain sections from AD model mice, as shown by synchrotron-radiation infrared microscopy analysis. Since Aβ 1-42 fibril absorbed a considerable FEL energy at amide I band (6.17 μm), we irradiated the FEL at 6.17 μm and found that β-sheet content of naked Aβ 1-42 fibril was decreased using infrared microscopic analysis. Consistent with the decrease in the β-sheet content, Congo-red signal is decreased after the irradiation to Aβ 1-42 fibril. Furthermore, electron microscopy analysis revealed that morphologies of the fibril and proto-fibril were largely changed after the irradiation. Thus, mid-infrared light dissociates β-sheet structure of Aβ fibrils, which justifies exploration of possible laser-based therapy for AD.

  17. Generalized theoretical method for the interaction between arbitrary nonuniform electric field and molecular vibrations: Toward near-field infrared spectroscopy and microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Iwasa, Takeshi, E-mail: tiwasa@mail.sci.hokudai.ac.jp; Takenaka, Masato; Taketsugu, Tetsuya

    A theoretical method to compute infrared absorption spectra when a molecule is interacting with an arbitrary nonuniform electric field such as near-fields is developed and numerically applied to simple model systems. The method is based on the multipolar Hamiltonian where the light-matter interaction is described by a spatial integral of the inner product of the molecular polarization and applied electric field. The computation scheme is developed under the harmonic approximation for the molecular vibrations and the framework of modern electronic structure calculations such as the density functional theory. Infrared reflection absorption and near-field infrared absorption are considered as model systems.more » The obtained IR spectra successfully reflect the spatial structure of the applied electric field and corresponding vibrational modes, demonstrating applicability of the present method to analyze modern nanovibrational spectroscopy using near-fields. The present method can use arbitral electric fields and thus can integrate two fields such as computational chemistry and electromagnetics.« less

  18. Generalized theoretical method for the interaction between arbitrary nonuniform electric field and molecular vibrations: Toward near-field infrared spectroscopy and microscopy.

    PubMed

    Iwasa, Takeshi; Takenaka, Masato; Taketsugu, Tetsuya

    2016-03-28

    A theoretical method to compute infrared absorption spectra when a molecule is interacting with an arbitrary nonuniform electric field such as near-fields is developed and numerically applied to simple model systems. The method is based on the multipolar Hamiltonian where the light-matter interaction is described by a spatial integral of the inner product of the molecular polarization and applied electric field. The computation scheme is developed under the harmonic approximation for the molecular vibrations and the framework of modern electronic structure calculations such as the density functional theory. Infrared reflection absorption and near-field infrared absorption are considered as model systems. The obtained IR spectra successfully reflect the spatial structure of the applied electric field and corresponding vibrational modes, demonstrating applicability of the present method to analyze modern nanovibrational spectroscopy using near-fields. The present method can use arbitral electric fields and thus can integrate two fields such as computational chemistry and electromagnetics.

  19. Near-Infrared Fluorescent Materials for Sensing of Biological Targets

    PubMed Central

    Amiot, Carrie L.; Xu, Shuping; Liang, Song; Pan, Lingyun; Zhao, Julia Xiaojun

    2008-01-01

    Near-infrared fluorescent (NIRF) materials are promising labeling reagents for sensitive determination and imaging of biological targets. In the near-infrared region biological samples have low background fluorescence signals, providing high signal to noise ratio. Meanwhile, near-infrared radiation can penetrate into sample matrices deeply due to low light scattering. Thus, in vivo and in vitro imaging of biological samples can be achieved by employing the NIRF probes. To take full advantage of NIRF materials in the biological and biomedical field, one of the key issues is to develop intense and biocompatible NIRF probes. In this review, a number of NIRF materials are discussed including traditional NIRF dye molecules, newly developed NIRF quantum dots and single-walled carbon nanotubes, as well as rare earth metal compounds. The use of some NIRF materials in various nanostructures is illustrated. The enhancement of NIRF using metal nanostructures is covered as well. The fluorescence mechanism and bioapplications of each type of the NIRF materials are discussed in details. PMID:27879867

  20. An infrared illuminator for a healing bed

    NASA Astrophysics Data System (ADS)

    Acharekar, Madhu A.; Crowley, Edward

    2011-05-01

    Bio-stimulation by a light is called the Light Therapy (LT) and an Infrared Illuminator (IRI) provides the human sleeping in a Healing Bed (HB) continuously a dose of the IR radiation. General specifications for the IRI given below and its data are discussed in the paper. (1) Use of 60" wide by 80" long queen size bed. (2) A LED providing 1.5 mw at 1550 nm is selected. (3) 60 LED are mounted in series and parallel on a chip and this chip is mounted on top of the HB.

  1. A clinical review of phototherapy for psoriasis.

    PubMed

    Zhang, Ping; Wu, Mei X

    2018-01-01

    Psoriasis is an autoimmune inflammatory skin disease. In the past several decades, phototherapy has been widely used to treat stable psoriatic lesions, including trunk, scalp, arms and legs, and partial nail psoriasis. A variety of light/lasers with different mechanisms of action have been developed for psoriasis including ultraviolet B (UVB), psoralen ultraviolet A (PUVA), pulsed dye laser (PDL), photodynamic therapy (PDT), intense pulsed light (IPL), light-emitting diodes (LED), and so on. Because light/laser each has specific therapeutic and adverse effects, it is important to adequately choose the sources and parameters in management of psoriasis with different pathogenic sites, severities, and duration of the disorder. This review aims at providing most updated clinic information to physicians about how to select light/laser sources and individual therapeutic regimens. To date, UV light is primarily for stable plaque psoriasis and PDL for topical psoriatic lesions with small area, both of which are safe and effective. On the other hand, PUVA has better curative effects than UVB for managing refractory psoriasis plaques, if its side effects can be better controlled. PDL provides optimal outcomes on nail psoriasis compared with other lasers. Although the trails of low-level light/laser therapy (LLLT) are still small, the near infrared (NIR) and visible red light with low energy show promise for treating psoriasis due to its strong penetration and encouraging photobiomodulation. IPL is rarely reported for psoriasis treatment, but PDT-IPL has been found to offer a moderate effect on nail psoriasis. In brief, various phototherapies have been used either in different combinations or as monotherapy. The modality has become a mainstay in the treatment of mild-to-moderate psoriasis without systemic adverse events in today's clinical practice.

  2. Treatment of complicated gangrene using infrared photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Szabo, Robert

    2018-04-01

    Antimicrobial photodynamic therapy (aPDT) is one of the treatment options of local infections. Conventional aPDT systems have physical limitations such as low light penetration and the need for long irradiation time to achieve the necessary light dose. With new forming specific complex of methylene blue dye molecules it is possible to reach efficient excitation processes at 810nm. At 810nm, there is increased light penetration depth in comparison to 670nm. This means that we are now able to excite the sensitizer in deeper areas and activate it transgingivally. Purpose Preserving teeth with complicated gangrene is a great challenge if root canal is obstructed. Lacking the possibility to perform the conventional mechanical cleaning of root canals. we have used infrared photodynamic therapy for elimination radicular bacterial infiltration Materials and methods We investigated 14 cases with complicated gangrene and totally or partially obstructed root canal. We deposited the sensitizer - Photolase Photolase GMBH Germany - in the pulp chamber and closed it for a week. This procedure was repeated three times. After the sensitizer penetrated we applied the light. We used G-Box 810 nm laser - Gigaa Laser China - at 0,8W/cm2 , 40s buccal and 40s oral side. Results 6 month later we performed follow-up CBCT. Out of 14 cases significant healing was detected in 10. In 4 cases no change was observable. Discussion and conclusion Infrared aPDT seems effective in eliminating bacterial infiltrations in deeper areas. It can be a minimal invasive method in the case of obstructed root canals.

  3. Photodynamic inactivation of microorganisms which cause pulmonary diseases with infrared light: an in vitro study

    NASA Astrophysics Data System (ADS)

    Leite, Ilaiáli S.; Geralde, Mariana C.; Salina, Ana C.; Medeiros, Alexandra I.; Kurachi, Cristina; Bagnato, Vanderlei S.; Inada, Natalia M.

    2014-03-01

    Lower respiratory infections are among the leading causes of death worldwide. In this study, it was evaluated the interaction of indocyanine green, a photosensitizer activated by infrared light, with alveolar macrophages and the effectiveness of the photodynamic therapy using this compound against Streptococcus pneumoniae . Initial experiments analyzed indocyanine green toxicity to alveolar macrophages in the dark with different drug concentrations and incubation times, and macrophage viability was obtained with the MTT method. The average of the results showed viability values below 90% for the two highest concentrations. Experiments with Streptococcus pneumoniae showed photodynamic inactivation with 10 μM indocyanine green solution. Further experiments with the bacteria in co-culture with AM will be conducted verifying the photodynamic inactivation effectiveness of the tested drug concentrations and incubation periods using infrared light.

  4. Development of a near-infrared spectroscopy instrument for applications in urology.

    PubMed

    Macnab, Andrew J; Stothers, Lynn

    2008-10-01

    Near infrared spectroscopy (NIRS) is an established technology using photons of light in the near infrared spectrum to monitor changes in tissue of naturally occurring chromophores, including oxygenated and deoxygenated hemoglobin. Technology and methodology have been validated for measurement of a range of physiologic parameters. NIRS has been applied successfully in urology research; however current instruments are designed principally for brain and muscle study. To describe development of a NIRS instrument specifically designed for monitoring changes in chromophore concentration in the bladder detrusor in real time, to facilitate research to establish the role of this non-invasive technology in the evaluation of patients with voiding dysfunction The portable continuous wave NIRS instrument has a 3 laser diode light source (785, 808 and 830 nanometers), fiber optic cables for light transmission, a self adhesive patient interface patch with an emitter and sensor, and software to detect the difference between the light transmitted and received by the instrument. Software incorporated auto-attenuates the optical signals and converts raw optical data into chromophore concentrations displayed graphically. The prototype was designed, tested, and iteratively developed to achieve optimal suprapubic transcutaneous monitoring of the detrusor in human subjects during bladder filling and emptying. Evaluation with simultaneous invasive urodynamic measurement in men and women indicates good specificity and sensitivity of NIRS chromophore concentration changes by receiver operator curve analysis, and correlation between NIRS data and urodynamic pressures. Urological monitoring with this NIRS instrument is feasible and generates data of potential diagnostic value.

  5. Near-infrared scintillation of liquid argon

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alexander, T.; Escobar, C. O.; Lippincott, W. H.

    2016-03-03

    Since the 1970s it has been known that noble gases scintillate in the near infrared (NIR) region of the spectrum (0.7more » $$\\mu$$m < $$\\lambda$$; < 1.5$$\\mu$$m). More controversial has been the question of the NIR light yield for condensed noble gases. We first present the motivation for using the NIR scintillation in liquid argon detectors, then briefly review early as well as more recent efforts and finally show encouraging preliminary results of a test performed at Fermilab.« less

  6. LIGHT TITRATIONS

    PubMed Central

    Field, John; Baas-Becking, Lourens G. M.

    1926-01-01

    1. The usefulness of the radiomicrometer in titration work has been pointed out. The authors suggest that light titration may also be used where a reaction mixture changes its absorption in the (near) infra-red. 2. The applicability of this method to the starch-iodine reaction has been demonstrated. PMID:19872266

  7. Theoretical and experimental investigation of near-infrared light propagation in a model of the adult head.

    PubMed

    Okada, E; Firbank, M; Schweiger, M; Arridge, S R; Cope, M; Delpy, D T

    1997-01-01

    Near-infrared light propagation in various models of the adult head is analyzed by both time-of-flight measurements and mathematical prediction. The models consist of three- or four-layered slabs, the latter incorporating a clear cerebrospinal fluid (CSF) layer. The most sophisticated model also incorporates slots that imitate sulci on the brain surface. For each model, the experimentally measured mean optical path length as a function of source-detector spacing agrees well with predictions from either a Monte Carlo model or a finite-element method based on diffusion theory or a hybrid radiosity-diffusion theory. Light propagation in the adult head is shown to be highly affected by the presence of the clear CSF layer, and both the optical path length and the spatial sensitivity profile of the models with a CSF layer are quite different from those without the CSF layer. However, the geometry of the sulci and the boundary between the gray and the white matter have little effect on the detected light distribution.

  8. Use of visible and near infrared reflectance spectra to predict lipid peroxidation of light lamb meat and discriminate dam's feeding systems.

    PubMed

    Ripoll, G; Lobón, S; Joy, M

    2018-09-01

    Measurement of thiobarbituric acid reactive substances (TBARS) is a well-established method for determine lipid oxidation in meat. This assay, however, is time-consuming and generates undesired chemical waste. Dam's milk is the principal source of vitamins and provitamins that delay lipid oxidation of light lamb meat; these compounds are stored in the lamb's muscle tissue. Hence, lamb meat could be used to determine the origin of the dam's diet. The aim of this study is to evaluate Near-infrared reflectance spectroscopy (NIRS) as a tool for determining the lipid peroxidation of light lamb meat and differentiate the meat of light lambs according the diet of their dams during lactation (grazing alfalfa, lucerne, or fed a total mixed ration). NIRS using select wavelengths was able to detect the lipid oxidation of meat (TBARS method). NIRS can detect analytes at concentrations of parts per million. Moreover, the feed diets were discriminated successfully. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. The 3.5 micron light curves of long period variable stars. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Strecker, D. W.

    1973-01-01

    Infrared observations at an effective wavelength of 3.5 microns of a selected group of long period variable (LPV) stars are presented. Mira type and semiregular stars of M, S, and C spectral classifications were monitored throughout the full cycle of variability. Although the variable infrared radiation does not exactly repeat in intensity or time, the regularity is sufficient to produce mean 3.5 micron light curves. The 3.5 micron maximum radiation lags the visual maximum by about one-seventh of a cycle, while the minimum 3.5 micron intensity occurs nearly one-half cycle after infrared maximum. In some stars, there are inflections or humps on the ascending portion of the 3.5 micron light curve which may also be seen in the visual variations.

  10. VizieR Online Data Catalog: Galaxies morphology and IR photometry III. (Gavazzi+, 2000)

    NASA Astrophysics Data System (ADS)

    Gavazzi, G.; Franzetti, P.; Scodeggio, M.; Boselli, A.; Pierini, D.; Baffa, C.; Lisi, F.; Hunt, L. K.

    1999-11-01

    We present near-infrared H-band (1.65μm) surface photometry of 558 galaxies in the Coma Supercluster and in the Virgo cluster. This data set, obtained with the Arcetri NICMOS3 camera ARNICA mounted on the Gornergrat Infrared Telescope, is aimed at complementing, with observations of mostly early-type objects, our NIR survey of spiral galaxies in these regions, presented in previous papers of this series. Magnitudes at the optical radius, total magnitudes, isophotal radii and light concentration indices are derived. We confirm the existence of a positive correlation between the near-infrared concentration index and the galaxy H-band luminosity (2 data files).

  11. Predicting color traits of intact broiler breast fillets using visible and infrared-light

    USDA-ARS?s Scientific Manuscript database

    The ability of using visible and near-infrared (Vis/NIR) spectroscopy with wavelengths ranging from 400 to 2500nm to predict broiler breast fillets color traits was assessed in this study. Deboning fillets from 214 carcasses slaughtered in a commercial processing plant were included in this work, sp...

  12. Non-invasive neuroimaging using near-infrared light

    NASA Technical Reports Server (NTRS)

    Strangman, Gary; Boas, David A.; Sutton, Jeffrey P.

    2002-01-01

    This article reviews diffuse optical brain imaging, a technique that employs near-infrared light to non-invasively probe the brain for changes in parameters relating to brain function. We describe the general methodology, including types of measurements and instrumentation (including the tradeoffs inherent in the various instrument components), and the basic theory required to interpret the recorded data. A brief review of diffuse optical applications is included, with an emphasis on research that has been done with psychiatric populations. Finally, we discuss some practical issues and limitations that are relevant when conducting diffuse optical experiments. We find that, while diffuse optics can provide substantial advantages to the psychiatric researcher relative to the alternative brain imaging methods, the method remains substantially underutilized in this field.

  13. A Giant Gathering of Galaxies

    NASA Image and Video Library

    2015-11-03

    The galaxy cluster called MOO J1142+1527 can be seen here as it existed when light left it 8.5 billion years ago. The red galaxies at the center of the image make up the heart of the galaxy cluster. This color image is constructed from multi-wavelength observations: Infrared observations from NASA's Spitzer Space Telescope are shown in red; near-infrared and visible light captured by the Gemini Observatory atop Mauna Kea in Hawaii is green and blue; and radio light from the Combined Array for Research in Millimeter-wave Astronomy (CARMA), near Owens Valley in California, is purple. In addition to galaxies, clusters also contain a reservoir of hot gas with temperatures in the tens of millions of degrees Celsius/Kelvin. CARMA was used to detect this gas, and to determine the mass of this cluster. http://photojournal.jpl.nasa.gov/catalog/PIA20052

  14. Near-Infrared Free-Radical and Free-Radical-Promoted Cationic Photopolymerizations by In-Source Lighting Using Upconverting Glass.

    PubMed

    Kocaarslan, Azra; Tabanli, Sevcan; Eryurek, Gonul; Yagci, Yusuf

    2017-11-13

    A method is presented for the initiation of free-radical and free-radical-promoted cationic photopolymerizations by in-source lighting in the near-infrared (NIR) region using upconverting glass (UCG). This approach utilizes laser irradiation of UCG at 975 nm in the presence of fluorescein (FL) and pentamethyldiethylene triamine (PMDETA). FL excited by light emitted from the UCG undergoes electron-transfer reactions with PMDETA to form free radicals capable of initiating polymerization of methyl methacrylate. To execute the corresponding free-radical-promoted cationic polymerization of cyclohexene oxide, isobutyl vinyl ether, and N-vinyl carbazole, it was necessary to use FL, dimethyl aniline (DMA), and diphenyliodonium hexafluorophosphate as sensitizer, coinitiator, and oxidant, respectively. Iodonium ions promptly oxidize DMA radicals formed to the corresponding cations. Thus, cationic polymerization with efficiency comparable to the conventional irradiation source was achieved. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Visualization of light propagation in visible Chinese human head for functional near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Ting; Gong, Hui; Luo, Qingming

    2011-04-01

    Using the visible Chinese human data set, which faithfully represents human anatomy, we visualize the light propagation in the head in detail based on Monte Carlo simulation. The simulation is verified to agree with published experimental results in terms of a differential path-length factor. The spatial sensitivity profile turns out to seem like a fat tropical fish with strong distortion along the folding cerebral surface. The sensitive brain region covers the gray matter and extends to the superficial white matter, leading to a large penetration depth (>3 cm). Finally, the optimal source-detector separation is suggested to be narrowed down to 3-3.5 cm, while the sensitivity of the detected signal to brain activation reaches the peak of 8%. These results indicate that the cerebral cortex folding geometry actually has substantial effects on light propagation, which should be necessarily considered for applications of functional near-infrared spectroscopy.

  16. Near-infrared light-responsive dynamic wrinkle patterns.

    PubMed

    Li, Fudong; Hou, Honghao; Yin, Jie; Jiang, Xuesong

    2018-04-01

    Dynamic micro/nanopatterns provide an effective approach for on-demand tuning of surface properties to realize a smart surface. We report a simple yet versatile strategy for the fabrication of near-infrared (NIR) light-responsive dynamic wrinkles by using a carbon nanotube (CNT)-containing poly(dimethylsiloxane) (PDMS) elastomer as the substrate for the bilayer systems, with various functional polymers serving as the top stiff layers. The high photon-to-thermal energy conversion of CNT leads to the NIR-controlled thermal expansion of the elastic CNT-PDMS substrate, resulting in dynamic regulation of the applied strain (ε) of the bilayer system by the NIR on/off cycle to obtain a reversible wrinkle pattern. The switchable surface topological structures can transfer between the wrinkled state and the wrinkle-free state within tens of seconds via NIR irradiation. As a proof-of-concept application, this type of NIR-driven dynamic wrinkle pattern was used in smart displays, dynamic gratings, and light control electronics.

  17. Inhomogeneity in optical properties of rat brain: a study for LLLT dosimetry

    NASA Astrophysics Data System (ADS)

    Sousa, Marcelo V. P.; Prates, Renato; Kato, Ilka T.; Sabino, Caetano P.; Yoshimura, Tania M.; Suzuki, Luis C.; Magalhães, Ana C.; Yoshimura, Elisabeth M.; Ribeiro, Martha S.

    2013-03-01

    Over the last few years, low-level light therapy (LLLT) has shown an incredible suitability for a wide range of applications for central nervous system (CNS) related diseases. In this therapeutic modality light dosimetry is extremely critical so the study of light propagation through the CNS organs is of great importance. To better understand how light intensity is delivered to the most relevant neural sites we evaluated optical transmission through slices of rat brain point by point. We experimented red (λ = 660 nm) and near infrared (λ = 808 nm) diode laser light analyzing the light penetration and distribution in the whole brain. A fresh Wistar rat (Rattus novergicus) brain was cut in sagittal slices and illuminated with a broad light beam. A high-resolution digital camera was employed to acquire data of transmitted light. Spatial profiles of the light transmitted through the sample were obtained from the images. Peaks and valleys in the profiles show sites where light was less or more attenuated. The peak intensities provide information about total attenuation and the peak widths are correlated to the scattering coefficient at that individual portion of the sample. The outcomes of this study provide remarkable information for LLLT dose-dependent studies involving CNS and highlight the importance of LLLT dosimetry in CNS organs for large range of applications in animal and human diseases.

  18. Assessment of incomplete clipping of aneurysms intraoperatively by a near-infrared indocyanine green-video angiography (Niicg-Va) integrated microscope.

    PubMed

    Imizu, S; Kato, Y; Sangli, A; Oguri, D; Sano, H

    2008-08-01

    The objective of this article was to assess the clinical use and the completeness of clipping with total occlusion of the aneurysmal lumen, real-time assessment of vascular patency in the parent, branching and perforating vessels, intraoperative assessment of blood flow, image quality, spatial resolution and clinical value in difficult aneurysms using near infrared indocyanine green video angiography integrated on to an operative Pentero neurosurgical microscope (Carl Zeiss, Oberkochen Germany). Thirteen patients with aneurysms were operated upon. An infrared camera with near infrared technology was adapted on to the OPMI Pentero microscope with a special filter and infrared excitation light to illuminate the operating field which was designed to allow passage of the near infrared light required for excitation of indocyanine green (ICG) which was used as the intravascular marker. The intravascular fluorescence was imaged with a video camera attached to the microscope. ICG fluorescence (700-850 nm) from a modified microscope light source on to the surgical field and passage of ICG fluorescence (780-950 nm) from the surgical field, back into the optical path of the microscope was used to detect the completeness of aneurysmal clipping Incomplete clipping in three patients (1 female and 2 males) with unruptured complicated aneurysms was detected using indocyanine green video angiography. There were no adverse effects after injection of indocyanine green. The completeness of clipping was inadequately detected by Doppler ultrasound miniprobe and rigid endoscopy and was thus complemented by indocyanine green video angiography. The operative microscope-integrated ICG video angiography as a new intraoperative method for detecting vascular flow, was found to be quick, reliable, cost-effective and possibly a substitute or adjunct for Doppler ultrasonography or intraoperative DSA, which is presently the gold standard. The simplicity of the method, the speed with which the investigation can be performed, the quality of the images, and the outcome of surgical procedures have all reduced the need for angiography. This technique may be useful during routine aneurysm surgery as an independent form of angiography and/or as an adjunct to intraoperative or postoperative DSA.

  19. Quantitative Near-field Microscopy of Heterogeneous and Correlated Electron Oxides

    NASA Astrophysics Data System (ADS)

    McLeod, Alexander Swinton

    Scanning near-field optical microscopy (SNOM) is a novel scanning probe microscopy technique capable of circumventing the conventional diffraction limit of light, affording unparalleled optical resolution (down to 10 nanometers) even for radiation in the infrared and terahertz energy regimes, with light wavelengths exceeding 10 micrometers. However, although this technique has been developed and employed for more than a decade to a qualitatively impressive effect, researchers have lacked a practically quantitative grasp of its capabilities, and its application scope has so far remained restricted by implementations limited to ambient atmospheric conditions. The two-fold objective of this dissertation work has been to address both these shortcomings. The first half of the dissertation presents a realistic, semi-analytic, and benchmarked theoretical description of probe-sample near-field interactions that form the basis of SNOM. Owing its name to the efficient nano-focusing of light at a sharp metallic apex, the "lightning rod model" of probe-sample near-field interactions is mathematically developed from a flexible and realistic scattering formalism. Powerful and practical applications are demonstrated through the accurate prediction of spectroscopic near-field optical contrasts, as well as the "inversion" of these spectroscopic contrasts into a quantitative description of material optical properties. Thus enabled, this thesis work proceeds to present quantitative applications of infrared near-field spectroscopy to investigate nano-resolved chemical compositions in a diverse host of samples, including technologically relevant lithium ion battery materials, astrophysical planetary materials, and invaluable returned extraterrestrial samples. The second half of the dissertation presents the design, construction, and demonstration of a sophisticated low-temperature scanning near-field infrared microscope. This instrument operates in an ultra-high vacuum environment suitable for the investigation of nano-scale physics in correlated electron matter at cryogenic temperatures, thus vastly expanding the scope of applications for infrared SNOM. Performance of the microscope is demonstrated through quanttiative exploration of the canonical insulator-metal transition occuring in the correlated electron insulator V2O3. The methodology established for this investigation provides a model for ongoing and future nano-optical studies of phase transitions and phase coexistence in correlated electron oxides.

  20. Lethal photosensitization of wound-associated microbes using indocyanine green and near-infrared light.

    PubMed

    Omar, Ghada S; Wilson, Michael; Nair, Sean P

    2008-07-01

    The increase in resistance to antibiotics among disease-causing bacteria necessitates the development of alternative antimicrobial approaches such as the use of light-activated antimicrobial agents (LAAAs). Light of an appropriate wavelength activates the LAAA to produce cytotoxic species which can then cause bacterial cell death via loss of membrane integrity, lipid peroxidation, the inactivation of essential enzymes, and/or exertion of mutagenic effects due to DNA modification. In this study, the effect of the LAAA indocyanine green excited with high or low intensity light (808 nm) from a near-infrared laser (NIR) on the viability of Staphylococcus aureus, Streptococcus pyogenes and Pseudomonas aeruginosa was investigated. All species were susceptible to killing by the LAAA, the bactericidal effect being dependent on both the concentration of indocyanine green and the light dose. Indocyanine green photosensitization using both high (1.37 W cm(-2)) and low (0.048 W cm(-2)) intensity NIR laser light was able to achieve reductions of 5.6 log10 (>99.99%) and 6.8 log10 (>99.99%) in the viable counts of Staph. aureus and Strep. pyogenes (using starting concentrations of 106-107 CFU ml(-1)). Kills of 99.99% were obtained for P. aeruginosa (initial concentration 108-109 CFU ml(-1)) photosensitized by the high intensity light (1.37 W cm(-2)); while a kill of 80% was achieved using low intensity irradiation (0.07 W cm(-2)). The effects of L-tryptophan (a singlet oxygen scavenger) and deuterium oxide (as an enhancer of the life span of singlet oxygen) on the survival of Staph. aureus was also studied. L-tryptophan reduced the proportion of Staph. aureus killed; whereas deuterium oxide increased the proportion killed suggesting that singlet oxygen was involved in the killing of the bacteria. These findings imply that indocyanine green in combination with light from a near-infrared laser may be an effective means of eradicating bacteria from wounds and burns.

  1. Near Infrared Photoimmunotherapy in the Treatment of Pleural Disseminated NSCLC: Preclinical Experience

    PubMed Central

    Sato, Kazuhide; Nagaya, Tadanobu; Choyke, Peter L.; Kobayashi, Hisataka

    2015-01-01

    Pleural metastases are common in patients with advanced thoracic cancers and are a cause of considerable morbidity and mortality yet is difficult to treat. Near Infrared Photoimmunotherapy (NIR-PIT) is a cancer treatment that combines the specificity of intravenously injected antibodies for targeting tumors with the toxicity induced by photosensitizers after exposure to NIR-light. Herein, we evaluate the efficacy of NIR-PIT in a mouse model of pleural disseminated non-small cell lung carcinoma (NSCLC). In vitro and in vivo experiments were conducted with a HER2, luciferase and GFP expressing NSCLC cell line (Calu3-luc-GFP). An antibody-photosensitizer conjugate (APC) consisting of trastuzumab and a phthalocyanine dye, IRDye-700DX, was synthesized. In vitro NIR-PIT cytotoxicity was assessed with dead staining, luciferase activity, and GFP fluorescence intensity. In vivo NIR-PIT was performed in mice with tumors implanted intrathoracic cavity or in the flank, and assessed by tumor volume and/or bioluminescence and fluorescence thoracoscopy. In vitro NIR-PIT-induced cytotoxicity was light dose dependent. In vivo NIR-PIT led significant reductions in both tumor volume (p = 0.002 vs. APC) and luciferase activity (p = 0.0004 vs. APC) in a flank model, and prolonged survival (p < 0.0001). Bioluminescence indicated that NIR-PIT lead to significant reduction in pleural dissemination (1 day after PIT; p = 0.0180). Fluorescence thoracoscopy confirmed the NIR-PIT effect on disseminated pleural disease. In conclusion, NIR-PIT has the ability to effectively treat pleural metastases caused by NSCLC in mice. Thus, NIR-PIT is a promising therapy for pleural disseminated tumors. PMID:25897335

  2. The Infrared Hunter

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2

    This image composite compares infrared and visible views of the famous Orion nebula and its surrounding cloud, an industrious star-making region located near the hunter constellation's sword. The infrared picture is from NASA's Spitzer Space Telescope, and the visible image is from the National Optical Astronomy Observatory, headquartered in Tucson, Ariz.

    In addition to Orion, two other nebulas can be seen in both pictures. The Orion nebula, or M42, is the largest and takes up the lower half of the images; the small nebula to the upper left of Orion is called M43; and the medium-sized nebula at the top is NGC 1977. Each nebula is marked by a ring of dust that stands out in the infrared view. These rings make up the walls of cavities that are being excavated by radiation and winds from massive stars. The visible view of the nebulas shows gas heated by ultraviolet radiation from the massive stars.

    Above the Orion nebula, where the massive stars have not yet ejected much of the obscuring dust, the visible image appears dark with only a faint glow. In contrast, the infrared view penetrates the dark lanes of dust, revealing bright swirling clouds and numerous developing stars that have shot out jets of gas (green). This is because infrared light can travel through dust, whereas visible light is stopped short by it.

    The infrared image shows light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.

  3. Novel endoscopic delivery modality of infrared coagulation therapy for internal hemorrhoids.

    PubMed

    McLemore, Elisabeth C; Rai, Rudra; Siddiqui, Junaid; Basu, P Patrick; Tabbaa, Mousab; Epstein, Michael S

    2012-11-01

    A novel endoscopic delivery system for infrared coagulation therapy (IRC) has been designed recently. IRC is a well-established treatment for symptomatic internal hemorrhoids. Patients frequently undergo lower endoscopy before hemorrhoid treatment to eliminate other sources of bleeding. Current treatment options are difficult to perform without an anal retractor, adequate lighting, and specialized instruments. Endoscopic IRC is an attractive alternative to standard IRC, because it can be performed during the lower endoscopy. Endoscopic IRC utilizes infrared radiation generated by a control box, which is applied to the tissue through a flexible, fiber optic light guide (Precision Endoscopic Infrared Coagulator™). The light guide is placed through the colonoscope or flexible sigmoidoscope in the same chamber as other endoscopic instruments. A retrospective review was performed using a prospectively collected database. A standardized protocol was utilized in all patients. Patients graded their symptoms before and after therapy by using the visual analog symptom severity scoring system (range, 0-10). These results were analyzed by using the nonparametric Wilcoxon signed-rank test. Exact P values were computed by using the R function wilcox.exact. A total of 55 patients underwent endoscopic IRC for predominately grade II and grade III symptomatic internal hemorrhoids (71 %). There were 22 (40 %) female patients. Posttherapy results indicated a significant improvement in global symptoms (pretreatment average global score = 2.24 vs. posttreatment average global score = 0.28; P < 0.0001). There have been no adverse events reported to date. Endoscopic IRC provides improved visibility and efficiency, allowing simultaneous treatment of symptomatic internal hemorrhoids at the time of lower endoscopy. Patients experienced significant improvement in their symptoms after a single session of endoscopic IRC. There are a variety of additional endoscopic IRC therapeutic utilities: endoscopic management of angiodysplasia, inflammation, hemostasis, and NOTES applications.

  4. Near-infrared spectroscopy of the adult head: effect of scattering and absorbing obstructions in the cerebrospinal fluid layer on light distribution in the tissue.

    PubMed

    Dehghani, H; Delpy, D T

    2000-09-01

    Previous modeling of near-infrared (NIR) light distribution in models of the adult head incorporating a clear nonscattering cerebrospinal fluid (CSF) layer have shown the latter to have a profound effect on the resulting photon measurement density function (PMDF). In particular, the presence of the CSF limits the PMDF largely to the outer cortical gray matter with little signal contribution from the deeper white matter. In practice, the CSF is not a simple unobstructed clear layer but contains light-scattering membranes and is crossed by various blood vessels. Using a radiosity-diffusion finite-element model, we investigated the effect on the PMDF of introducing intrusions within the clear layer. The results show that the presence of such obstructions does not significantly increase the light penetration into the brain tissue, except immediately adjacent to the obstruction and that its presence also increases the light sampling of the adjacent skull tissues, which would lead to additional contamination of the NIR spectroscopy signal by the surface tissue layers.

  5. Use of nonthermal blue (405- to 420-nm) and near-infrared light (850- to 900-nm) dual-wavelength system in combination with glycolic acid peels and topical vitamin C for skin photorejuvenation.

    PubMed

    Fournier, Nathalie; Fritz, Klaus; Mordon, Serge

    2006-09-01

    A major cause of skin aging is a chronic microinflammation created by environmental conditions and ultraviolet exposures. The hand-free application on the skin of a new intense light combining a narrowband blue-light (405- to 420-nm) antiinflammatory emission and a near-infrared (850- to 890-nm) emission inducing self-defense mechanisms provides a new component to photorejuvenation and antiaging treatment protocols. An innovative skin rejuvenation schedule is presented in this study. It includes skin exposure to the light, with concomitant glycolic peels and daily vitamin C cream regimen for group A and only topical vitamin C cream and glycolic peels for control group B. Results show a significant improvement on pore size, rhytids, and radiance in group A. Conversely no improvement is noticed in group B except for a brief increase of skin radiance. Mechanisms of action of that specific light source are discussed. The exposure to this device can clinically enhance conventional antiaging protocols in skin rejuvenation.

  6. Generalized Beer-Lambert model for near-infrared light propagation in thick biological tissues

    NASA Astrophysics Data System (ADS)

    Bhatt, Manish; Ayyalasomayajula, Kalyan R.; Yalavarthy, Phaneendra K.

    2016-07-01

    The attenuation of near-infrared (NIR) light intensity as it propagates in a turbid medium like biological tissue is described by modified the Beer-Lambert law (MBLL). The MBLL is generally used to quantify the changes in tissue chromophore concentrations for NIR spectroscopic data analysis. Even though MBLL is effective in terms of providing qualitative comparison, it suffers from its applicability across tissue types and tissue dimensions. In this work, we introduce Lambert-W function-based modeling for light propagation in biological tissues, which is a generalized version of the Beer-Lambert model. The proposed modeling provides parametrization of tissue properties, which includes two attenuation coefficients μ0 and η. We validated our model against the Monte Carlo simulation, which is the gold standard for modeling NIR light propagation in biological tissue. We included numerous human and animal tissues to validate the proposed empirical model, including an inhomogeneous adult human head model. The proposed model, which has a closed form (analytical), is first of its kind in providing accurate modeling of NIR light propagation in biological tissues.

  7. Clinical application of near-infrared spectroscopy in patients with traumatic brain injury: a review of the progress of the field.

    PubMed

    Sen, Anish N; Gopinath, Shankar P; Robertson, Claudia S

    2016-07-01

    Near-infrared spectroscopy (NIRS) is a technique by which the interaction between light in the near-infrared spectrum and matter can be quantitatively measured to provide information about the particular chromophore. Study into the clinical application of NIRS for traumatic brain injury (TBI) began in the 1990s with early reports of the ability to detect intracranial hematomas using NIRS. We highlight the advances in clinical applications of NIRS over the past two decades as they relate to TBI. We discuss recent studies evaluating NIRS techniques for intracranial hematoma detection, followed by the clinical application of NIRS in intracranial pressure and brain oxygenation measurement, and conclude with a summary of potential future uses of NIRS in TBI patient management.

  8. Near-infrared supercontinuum laser beam source in the second and third near-infrared optical windows used to image more deeply through thick tissue as compared with images from a lamp source

    NASA Astrophysics Data System (ADS)

    Sordillo, Laura A.; Lindwasser, Lukas; Budansky, Yury; Leproux, Philippe; Alfano, Robert R.

    2015-03-01

    With the use of longer near-infrared (NIR) wavelengths, image quality can be increased due to less scattering (described by the inverse wavelength power dependence 1/λn where n≥1) and minimal absorption from water molecules. Longer NIR windows, known as the second (1100 nm to 1350 nm) and third (1600 to 1870 nm) NIR windows are utilized to penetrate more deeply into tissue media and produce high-quality images. An NIR supercontinuum (SC) laser light source, with wavelengths in the second and third NIR optical windows to image tissue provides ballistic imaging of tissue. The SC ballistic beam can penetrate depths of up to 10 mm through tissue.

  9. Effect of magnetic nanoparticles size on rheumatoid arthritis targeting and photothermal therapy.

    PubMed

    Zhang, Shengchang; Wu, Lin; Cao, Jin; Wang, Kaili; Ge, Yanru; Ma, Wanjun; Qi, Xueyong; Shen, Song

    2018-06-13

    Nanoparticles based multifunctional system exhibits great potential in diagnosis and therapy of rheumatoid arthritis (RA). The size of nanoparticles plays an essential role in biodistribution and cellular uptake, in turn affects the drug delivery efficiency and therapeutic effect. To investigate the optimal size for RA targeting, Fe 3 O 4 nanoparticles with well-defined particle sizes (70-350 nm) and identical surface properties were developed as model nanoparticles. The synthesized Fe 3 O 4 nanoparticles exhibited excellent biocompatibility and showed higher temperature response under irradiation of near infrared light. Size-dependent internalization was observed when incubated with inflammatory cells. Compared with large ones, small nanoparticles were more readily be phagocytized, leading to higher cytotoxicity in vitro. However, the in vivo experiment in CIA mice demonstrated a quite different result that nanoparticles with size of 220 nm exerted better accessibility to inflamed joint and resulted in higher temperature and better therapeutic effect under laser irradiation. This study not only offered a novel method for RA therapy but also a guideline for RA targeted drug carrier design. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Physiological Effects of Continuous Colored Light Exposure on Mayer Wave Activity in Cerebral Hemodynamics: A Functional Near-Infrared Spectroscopy (fNIRS) Study.

    PubMed

    Metz, A J; Klein, S D; Scholkmann, F; Wolf, U

    2017-01-01

    We are increasingly exposed to colored light, but its impact on human physiology is not yet extensively investigated. In the present study we aimed to determine the effects of colored light on human cerebral Mayer wave activity (MWA). We measured oxy- ([O 2 Hb]), deoxy- ([HHb]), total hemoglobin ([tHb]) concentrations and tissue oxygen saturation (StO 2 ) by functional near-infrared spectroscopy (fNIRS) in the left and right pre-frontal cortex (L-PFC, R-PFC) of 17 subjects (median age: 29 years, 6 women). In a randomized crossover design subjects were exposed to blue, red, green, and yellow LED light for 10 min. Pre-light (8 min, baseline) and post-light (15 min, recovery) conditions were darkness. MWA was calculated from band-pass filtered fNIRS signals (~0.08-0.12 Hz). The medians from the last 3 min of each period (baseline, light exposure, recovery) were statistically analyzed. MWA was increased during red and green light vs. baseline and after blue light exposure in recovery in the L-PFC. MWA differed depending on the chosen frequency range, filter design, and type of signals to analyze (raw intensity, hemoglobin signal from multi-distance method or modified Beer-Lambert law, or within hemoglobin signals).

  11. Observations of Planet Crossing Asteroids

    NASA Technical Reports Server (NTRS)

    Tholen, David J.

    1999-01-01

    This grant funds the investigation of the Solar System's planet crossing asteroid population, principally the near Earth and trans-Neptunian objects, but also the Centaurs. Investigations include colorimetry at both visible and near infrared wavelengths, light curve photometry, astrometry, and a pilot project to find near Earth objects with small aphelion distances, which requires observations at small solar elongations.

  12. Overcoming photodynamic resistance and tumor targeting dual-therapy mediated by indocyanine green conjugated gold nanospheres.

    PubMed

    Li, Wei; Guo, Xiaomeng; Kong, Fenfen; Zhang, Hanbo; Luo, Lihua; Li, Qingpo; Zhu, Chunqi; Yang, Jie; Du, Yongzhong; You, Jian

    2017-07-28

    Photodynamic therapy (PDT) and photothermal therapy (PTT) have captured much attention due to the great potential to cure malignant tumor. Nevertheless, photodynamic resistance of cancer cells has limited the further efficacy of PDT. Unfortunately, the resistance mechanism and efforts to overcome the resistance still have been rarely reported so far. Here, we report a nanosystem with specific tumor targeting for combined PDT and PTT mediated by near-infrared (NIR) light, which was established by covalently conjugating indocyanine green (ICG) and TNYL peptide onto the surface of hollow gold nanospheres (HAuNS). Our nanosystem (TNYL-ICG-HAuNS) was proved to possess significantly increased light stability, reactive oxygen species (ROS) production and photothermal effect under NIR light irradiation, thus presenting a remarkably enhanced antitumor efficacy. The up-regulation of nuclear factor erythroid 2-related factor 2 (NFE2L2, Nrf2) in cancer cells during PDT induced a significant increase of ABCG2, NQO-1 and HIF-1α expression, causing PDT resistance of the cells. Interestingly, ABCG2 expression could almost keep a normal level in the whole PDT process mediated by TNYL-ICG-HAuNS. After repeated irradiations, TNYL-ICG-HAuNS could still produce almost constant ROS in cells while the Nrf2 expression reduced significantly. Furthermore, PDT resistance induced an obvious decrease of the internalization of free ICG, but didn't influence the cell uptake of TNYL-ICG-HAuNS. Our data explained that TNYL-ICG-HAuNS could overcome the photodynamic resistance of cancer cells, acting as a promising modality for simultaneous photothermal and photodynamic cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Low-level light therapy potentiates NPe6-mediated photodynamic therapy in a human osteosarcoma cell line via increased ATP.

    PubMed

    Tsai, Shang-Ru; Yin, Rui; Huang, Ying-Ying; Sheu, Bor-Ching; Lee, Si-Chen; Hamblin, Michael R

    2015-03-01

    Low-level light therapy (LLLT) is used to stimulate healing, reduce pain and inflammation, and preserve tissue from dying. LLLT has been shown to protect cells in culture from dying after various cytotoxic insults, and LLLT is known to increase the cellular ATP content. Previous studies have demonstrated that maintaining a sufficiently high ATP level is necessary for the efficient induction and execution of apoptosis steps after photodynamic therapy (PDT). We asked whether LLLT would protect cells from cytotoxicity due to PDT, or conversely whether LLLT would enhance the efficacy of PDT mediated by mono-l-aspartyl chlorin(e6) (NPe6). Increased ATP could lead to enhanced cell uptake of NPe6 by the energy dependent process of endocytosis, and also to more efficient apoptosis. In this study, human osteosarcoma cell line MG-63 was subjected to 1.5J/cm(2) of 810nm near infrared radiation (NIR) followed by addition of 10μM NPe6 and after 2h incubation by 1.5J/cm(2) of 652nm red light for PDT. PDT combined with LLLT led to higher cell death and increased intracellular reactive oxygen species compared to PDT alone. The uptake of NPe6 was moderately increased by LLLT, and cellular ATP was increased. The mitochondrial respiratory chain inhibitor antimycin A abrogated the LLLT-induced increase in cytotoxicity. Taken together, these results demonstrate that LLLT potentiates NPe6-mediated PDT via increased ATP synthesis and is a potentially promising strategy that could be applied in clinical PDT. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Recent Advances of Light-Mediated Theranostics

    PubMed Central

    Ai, Xiangzhao; Mu, Jing; Xing, Bengang

    2016-01-01

    Currently, precision theranostics have been extensively demanded for the effective treatment of various human diseases. Currently, efficient therapy at the targeted disease areas still remains challenging since most available drug molecules lack of selectivity to the pathological sites. Among different approaches, light-mediated therapeutic strategy has recently emerged as a promising and powerful tool to precisely control the activation of therapeutic reagents and imaging probes in vitro and in vivo, mostly attributed to its unique properties including minimally invasive capability and highly spatiotemporal resolution. Although it has achieved initial success, the conventional strategies for light-mediated theranostics are mostly based on the light with short wavelength (e.g., UV or visible light), which may usually suffer from several undesired drawbacks, such as limited tissue penetration depth, unavoidable light absorption/scattering and potential phototoxicity to healthy tissues, etc. Therefore, a near-infrared (NIR) light-mediated approach on the basis of long-wavelength light (700-1000 nm) irradiation, which displays deep-tissue penetration, minimized photo-damage and low autofluoresence in living systems, has been proposed as an inspiring alternative for precisely phototherapeutic applications in the last decades. Despite numerous NIR light-responsive molecules have been currently proposed for clinical applications, several inherent drawbacks, such as troublesome synthetic procedures, low water solubility and limited accumulation abilities in targeted areas, heavily restrict their applications in deep-tissue therapeutic and imaging studies. Thanks to the amazing properties of several nanomaterials with large extinction coefficient in the NIR region, the construction of NIR light responsive nanoplatforms with multifunctions have become promising approaches for deep-seated diseases diagnosis and therapy. In this review, we summarized various light-triggered theranostic strategies and introduced their great advances in biomedical applications in recent years. Moreover, some other promising light-assisted techniques, such as photoacoustic and Cerenkov radiation, were also systemically discussed. Finally, the potential challenges and future perspectives for light-mediated deep-tissue diagnosis and therapeutics were proposed. PMID:27877246

  15. Hubble Tracks Clouds on Uranus

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Taking its first peek at Uranus, NASA Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) has detected six distinct clouds in images taken July 28,1997.

    The image on the right, taken 90 minutes after the left-hand image, shows the planet's rotation. Each image is a composite of three near-infrared images. They are called false-color images because the human eye cannot detect infrared light. Therefore, colors corresponding to visible light were assigned to the images. (The wavelengths for the 'blue,' 'green,' and 'red' exposures are 1.1, 1.6, and 1.9 micrometers, respectively.)

    At visible and near-infrared light, sunlight is reflected from hazes and clouds in the atmosphere of Uranus. However, at near-infrared light, absorption by gases in the Uranian atmosphere limits the view to different altitudes, causing intense contrasts and colors.

    In these images, the blue exposure probes the deepest atmospheric levels. A blue color indicates clear atmospheric conditions, prevalent at mid-latitudes near the center of the disk. The green exposure is sensitive to absorption by methane gas, indicating a clear atmosphere; but in hazy atmospheric regions, the green color is seen because sunlight is reflected back before it is absorbed. The green color around the south pole (marked by '+') shows a strong local haze. The red exposure reveals absorption by hydrogen, the most abundant gas in the atmosphere of Uranus. Most sunlight shows patches of haze high in the atmosphere. A red color near the limb (edge) of the disk indicates the presence of a high-altitude haze. The purple color to the right of the equator also suggests haze high in the atmosphere with a clear atmosphere below.

    The five clouds visible near the right limb rotated counterclockwise during the time between both images. They reach high into the atmosphere, as indicated by their red color. Features of such high contrast have never been seen before on Uranus. The clouds are almost as large as continents on Earth, such as Europe. Another cloud (which barely can be seen) rotated along the path shown by the black arrow. It is located at lower altitudes, as indicated by its green color.

    The rings of Uranus are extremely faint in visible light but quite prominent in the near infrared. The brightest ring, the epsilon ring, has a variable width around its circumference. Its widest and thus brightest part is at the top in this image. Two fainter, inner rings are visible next to the epsilon ring.

    Eight of the 10 small Uranian satellites, discovered by Voyager 2, can be seen in both images. Their sizes range from about 25 miles (40 kilometers) for Bianca to 100 miles (150 kilometers) for Puck. The smallest of these satellites have not been detected since the departure of Voyager 2 from Uranus in 1986. These eight satellites revolve around Uranus in less than a day. The inner ones are faster than the outer ones. Their motion in the 90 minutes between both images is marked in the right panel. The area outside the rings was slightly enhanced in brightness to improve the visibility of these faint satellites.

    The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.

    This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  16. HUBBLE TRACKS CLOUDS ON URANUS

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Taking its first peek at Uranus, NASA Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) has detected six distinct clouds in images taken July 28,1997. The image on the right, taken 90 minutes after the left-hand image, shows the planet's rotation. Each image is a composite of three near-infrared images. They are called false-color images because the human eye cannot detect infrared light. Therefore, colors corresponding to visible light were assigned to the images. (The wavelengths for the 'blue,' 'green,' and 'red' exposures are 1.1, 1.6, and 1.9 micrometers, respectively.) At visible and near-infrared light, sunlight is reflected from hazes and clouds in the atmosphere of Uranus. However, at near-infrared light, absorption by gases in the Uranian atmosphere limits the view to different altitudes, causing intense contrasts and colors. In these images, the blue exposure probes the deepest atmospheric levels. A blue color indicates clear atmospheric conditions, prevalent at mid-latitudes near the center of the disk. The green exposure is sensitive to absorption by methane gas, indicating a clear atmosphere; but in hazy atmospheric regions, the green color is seen because sunlight is reflected back before it is absorbed. The green color around the south pole (marked by '+') shows a strong local haze. The red exposure reveals absorption by hydrogen, the most abundant gas in the atmosphere of Uranus. Most sunlight shows patches of haze high in the atmosphere. A red color near the limb (edge) of the disk indicates the presence of a high-altitude haze. The purple color to the right of the equator also suggests haze high in the atmosphere with a clear atmosphere below. The five clouds visible near the right limb rotated counterclockwise during the time between both images. They reach high into the atmosphere, as indicated by their red color. Features of such high contrast have never been seen before on Uranus. The clouds are almost as large as continents on Earth, such as Europe. Another cloud (which barely can be seen) rotated along the path shown by the black arrow. It is located at lower altitudes, as indicated by its green color. The rings of Uranus are extremely faint in visible light but quite prominent in the near infrared. The brightest ring, the epsilon ring, has a variable width around its circumference. Its widest and thus brightest part is at the top in this image. Two fainter, inner rings are visible next to the epsilon ring. Eight of the 10 small Uranian satellites, discovered by Voyager 2, can be seen in both images. Their sizes range from about 25 miles (40 kilometers) for Bianca to 100 miles (150 kilometers) for Puck. The smallest of these satellites have not been detected since the departure of Voyager 2 from Uranus in 1986. These eight satellites revolve around Uranus in less than a day. The inner ones are faster than the outer ones. Their motion in the 90 minutes between both images is marked in the right panel. The area outside the rings was slightly enhanced in brightness to improve the visibility of these faint satellites. Credits: Erich Karkoschka (University of Arizona), and NASA.

  17. Narrowband infrared emitters for combat ID

    NASA Astrophysics Data System (ADS)

    Pralle, Martin U.; Puscasu, Irina; Daly, James; Fallon, Keith; Loges, Peter; Greenwald, Anton; Johnson, Edward

    2007-04-01

    There is a strong desire to create narrowband infrared light sources as personnel beacons for application in infrared Identify Friend or Foe (IFF) systems. This demand has augmented dramatically in recent years with the reports of friendly fire casualties in Afghanistan and Iraq. ICx Photonics' photonic crystal enhanced TM (PCE TM) infrared emitter technology affords the possibility of creating narrowband IR light sources tuned to specific IR wavebands (near 1-2 microns, mid 3-5 microns, and long 8-12 microns) making it the ideal solution for infrared IFF. This technology is based on a metal coated 2D photonic crystal of air holes in a silicon substrate. Upon thermal excitation the photonic crystal modifies the emitted yielding narrowband IR light with center wavelength commensurate with the periodicity of the lattice. We have integrated this technology with microhotplate MEMS devices to yield 15mW IR light sources in the 3-5 micron waveband with wall plug efficiencies in excess of 10%, 2 orders of magnitude more efficient that conventional IR LEDs. We have further extended this technology into the LWIR with a light source that produces 9 mW of 8-12 micron light at an efficiency of 8%. Viewing distances >500 meters were observed with fielded camera technologies, ideal for ground to ground troop identification. When grouped into an emitter panel, the viewing distances were extended to 5 miles, ideal for ground to air identification.

  18. CR-39 (PADC) Reflection and Transmission of Light in the Ultraviolet-Near-Infrared (UV-NIR) Range.

    PubMed

    Traynor, Nathan B J; McLauchlin, Christopher; Dodge, Kenneth; McGarrah, James E; Padalino, Stephen J; McCluskey, Michelle; Sangster, T C; McLean, James G

    2018-04-01

    The spectral reflection (specular and diffuse) and transmission of Columbia Resin 39 (CR-39) were measured for incoherent light with wavelengths in the range of 200-2500 nm. These results will be of use for the optical characterization of CR-39, as well as in investigations of the chemical modifications of the polymer caused by ultraviolet (UV) exposure. A Varian Cary 5000 was used to perform spectroscopy on several different thicknesses of CR-39. With proper analysis for the interdependence of reflectance and transmittance, results are consistent across all samples. The reflectivity from each CR-39-air boundary reveals an increase in the index of refraction in the near-UV. Absorption observations are consistent with the Beer-Lambert law. Strong absorption of UV light of wavelength shorter than 350 nm suggests an optical band gap of 3.5 eV, although the standard analysis is not conclusive. Absorption features observed in the near infrared are assigned to molecular vibrations, including some that are new to the literature.

  19. Photothermal cancer therapy using intravenously injected near-infrared-absorbing nanoparticles

    NASA Astrophysics Data System (ADS)

    O'Neal, D. P.; Hirsch, Leon R.; Halas, Naomi J.; Payne, J. D.; West, Jennifer L.

    2005-04-01

    This report focuses on the treatment parameters leading to successful nanoshell-assisted photo-thermal therapy (NAPT). NAPT takes advantage of the strong near infrared (NIR) absorption of gold-silica nanoshells, a new class of nanoparticles with tunable optical absorptivities that are capable of passive extravasation from the abnormal tumor vasculature due to their nanoscale size. Under controlled conditions nanoshells accumulate in tumors with superior efficiency compared to surrounding tissues. For this treatment: (1) tumors were inoculated in immune-competent mice by subcutaneous injection, (2) polyethylene glycol coated nanoshells (~150 nm diameter) with peak optical absorption in the NIR were intravenously injected and allowed to circulate for 6 - 48 hours, and (3) tumors were then extracorporeally illuminated with a collimated diode laser (808 nm, 2-6 W/cm2, 2-4 min). Nanoshell accumulations were quantitatively assessed in tumors and surrounding tissues using neutron activation analysis for gold. In order to assess temperature elevation, laser therapies were monitored in real-time using a mid-infrared thermal sensor. NAPT resulted in complete tumor regression in >90% of the subjects. This simple, non-invasive procedure shows great promise as a technique for selective photo-thermal tumor treatment.

  20. Near-infrared autofluorescence induced by intraplaque hemorrhage and heme degradation as marker for high-risk atherosclerotic plaques.

    PubMed

    Htun, Nay Min; Chen, Yung Chih; Lim, Bock; Schiller, Tara; Maghzal, Ghassan J; Huang, Alex L; Elgass, Kirstin D; Rivera, Jennifer; Schneider, Hans G; Wood, Bayden R; Stocker, Roland; Peter, Karlheinz

    2017-07-13

    Atherosclerosis is a major cause of mortality and morbidity, which is mainly driven by complications such as myocardial infarction and stroke. These complications are caused by thrombotic arterial occlusion localized at the site of high-risk atherosclerotic plaques, of which early detection and therapeutic stabilization are urgently needed. Here we show that near-infrared autofluorescence is associated with the presence of intraplaque hemorrhage and heme degradation products, particularly bilirubin by using our recently created mouse model, which uniquely reflects plaque instability as seen in humans, and human carotid endarterectomy samples. Fluorescence emission computed tomography detecting near-infrared autofluorescence allows in vivo monitoring of intraplaque hemorrhage, establishing a preclinical technology to assess and monitor plaque instability and thereby test potential plaque-stabilizing drugs. We suggest that near-infrared autofluorescence imaging is a novel technology that allows identification of atherosclerotic plaques with intraplaque hemorrhage and ultimately holds promise for detection of high-risk plaques in patients.Atherosclerosis diagnosis relies primarily on imaging and early detection of high-risk atherosclerotic plaques is important for risk stratification of patients and stabilization therapies. Here Htun et al. demonstrate that vulnerable atherosclerotic plaques generate near-infrared autofluorescence that can be detected via emission computed tomography.

  1. A Smart Responsive Dual Aptamers-Targeted Bubble-Generating Nanosystem for Cancer Triplex Therapy and Ultrasound Imaging.

    PubMed

    Zhao, Feifei; Zhou, Jie; Su, Xiangjie; Wang, Yuhui; Yan, Xiaosa; Jia, Shaona; Du, Bin

    2017-05-01

    The absence of targeted, single treatment methods produces low therapeutic value for treating cancers. To increase the accumulation of drugs in tumors and improve the treatment effectiveness, near-infrared 808 nm photothermal responsive dual aptamers-targeted docetaxel (DTX)-containing nanoparticles is proposed. In this system, DTX and NH 4 HCO 3 are loaded in thermosensitive liposomes. The surface of liposomes is coated with gold nanoshells and connected with sulfydryl (SH) modified AS1411 and S2.2 aptamers. The nanosystem has good biocompatibility and uniform size (diameter about 200 nm). The drug is rapidly released, reaching a maximum amount (84%) at 4 h under 808 nm laser irradiation. The experiments conducted in vitro and in vivo demonstrate the nanosystem can synergistically inhibit tumor growth by combination of chemotherapy, photothermal therapy, and biological therapy. Dual ligand functionalization significantly increases cellular uptake on breast cancer cell line (MCF-7) cells and achieves ultrasound imaging (USI) at tumor site. The results indicate that this drug delivery system is a promising theranostic agent involving light-thermal response at tumor sites, dual ligand targeted triplex therapy, and USI. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Optical properties of mice skin for optical therapy relevant wavelengths: influence of gender and pigmentation

    NASA Astrophysics Data System (ADS)

    Sabino, C. P.; Deana, A. M.; Silva, D. F. T.; França, C. M.; Yoshimura, T. M.; Ribeiro, M. S.

    2015-03-01

    Red and near-infrared light have been widely employed in optical therapies. Skin is the most common optical barrier in non-invasive techniques and in many cases it is the target tissue itself. Consequently, to optimize the outcomes brought by lightbased therapies, the optical properties of skin tissue must be very well elucidated. In the present study, we evaluated the dorsal skin optical properties of albino (BALB/c) and pigmented (C57BL/6) mice using the Kubelka-Munk photon transport model. We evaluated samples from male and female young mice of both strains. Analysis was performed for wavelengths at 630, 660, 780, 810 and 905 nm due to their prevalent use in optical therapies, such as low-level light (or laser) and photodynamic therapies. Spectrophotometric measurements of diffuse transmittance and reflectance were performed using a single integrating sphere coupled to a proper spectrophotometer. Statistic analysis was made by two-way ANOVA, with Tukey as post-test and Levenne and Shapiro-Wilks as pre-tests. Statistical significance was considered when p<0.05. Our results show only a slight transmittance increment (<10 %) as wavelengths are increased from 630 to 905 nm, and no statistical significance was observed. Albino male mice present reduced transmittance levels for all wavelengths. The organization and abundance of skin composing tissues significantly influence its scattering optical properties although absorption remains constant. We conclude that factors such as subcutaneous adiposity and connective tissue structure can have statistically significant influence on mice skin optical properties and these factors have relevant variations among different gender and strains.

  3. Astronomers Set a New Galaxy Distance Record

    NASA Image and Video Library

    2015-05-06

    This is a Hubble Space Telescope image of the farthest spectroscopically confirmed galaxy observed to date (inset). It was identified in this Hubble image of a field of galaxies in the CANDELS survey (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey). NASA’s Spitzer Space Telescope also observed the unique galaxy. The W. M. Keck Observatory was used to obtain a spectroscopic redshift (z=7.7), extending the previous redshift record. Measurements of the stretching of light, or redshift, give the most reliable distances to other galaxies. This source is thus currently the most distant confirmed galaxy known, and it appears to also be one of the brightest and most massive sources at that time. The galaxy existed over 13 billion years ago. The near-infrared light image of the galaxy (inset) has been colored blue as suggestive of its young, and hence very blue, stars. The CANDELS field is a combination of visible-light and near-infrared exposures. Read more: www.nasa.gov/feature/goddard/astronomers-set-a-new-galaxy... Credits: NASA, ESA, P. Oesch (Yale U.) NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  4. Spitzer Spies Spectacular Sombrero

    NASA Image and Video Library

    2005-05-04

    NASA's Spitzer Space Telescope set its infrared eyes on one of the most famous objects in the sky, Messier 104, also called the Sombrero galaxy. In this striking infrared picture, Spitzer sees an exciting new view of a galaxy that in visible light has been likened to a "sombrero," but here looks more like a "bulls-eye." Recent observations using Spitzer's infrared array camera uncovered the bright, smooth ring of dust circling the galaxy, seen in red. In visible light, because this galaxy is seen nearly edge-on, only the near rim of dust can be clearly seen in silhouette. Spitzer's full view shows the disk is warped, which is often the result of a gravitational encounter with another galaxy, and clumpy areas spotted in the far edges of the ring indicate young star-forming regions. Spitzer's infrared view of the starlight from this galaxy, seen in blue, can pierce through obscuring murky dust that dominates in visible light. As a result, the full extent of the bulge of stars and an otherwise hidden disk of stars within the dust ring are easily seen. The Sombrero galaxy is located some 28 million light years away. Viewed from Earth, it is just six degrees south of its equatorial plane. Spitzer detected infrared emission not only from the ring, but from the center of the galaxy too, where there is a huge black hole, believed to be a billion times more massive than our Sun. This picture is composed of four images taken at 3.6 (blue), 4.5 (green), 5.8 (orange), and 8.0 (red) microns. The contribution from starlight (measured at 3.6 microns) has been subtracted from the 5.8 and 8-micron images to enhance the visibility of the dust features. http://photojournal.jpl.nasa.gov/catalog/PIA07899

  5. Cobalamin-fluorophores' photochemistry and biomedical applications

    NASA Astrophysics Data System (ADS)

    Rodgers, Zachary Lewis

    As science focuses on the finer details of complex processes occurring in biology, the need for tools responsive to researcher control have become critical to communicate with cellular functions in both a spatial and temporal manner. To this end, light responsive "caging groups" have been used to generate molecular constructs with which researchers can activate using directed irradiation to elicit biological responses where and when they want. This advancement in molecular control has greatly improved our ability to study biological systems in their dynamically intricate form. Most of these photoresponsive moieties perform well within a petri dish, but their application is limited in vivo. Current photochemical tools require high energy light for their activation. Dermal tissue contains bio chromophores that absorb this light and prevents its penetration to less than a few millimeters making photoactivation impossible. However, tissue has an "optical window" in the red and near infrared (600 -- 1000 nm) where light penetrates efficiently to clinically relevant depths. Therefore, researchers have sought long wavelength responsive caging groups but have had little success to date. Herein, I report the development of an entire class of red and near infrared responsive (600 -- 800 nm) caging groups based on Vitamin B12 or cobalamin. Upon modification with a fluorophore antenna, these metal complexes can capture long wavelength light to perform photochemical work in the form of bond scission reactions. The effect is compatible with a range of fluorophores covering the entire near infrared spectrum, and bond scission proceeds rapidly with extremely high efficiencies. In this work, the initial development and characterization of these molecules as photoactivateable groups will be discussed. Furthermore, I will demonstrate how these molecules can be applied for clinical applications, such as drug delivery and tissue scaffold formation, to provide safer and less invasive treatments.

  6. Conformational changes in matrix-isolated 6-methoxyindole: Effects of the thermal and infrared light excitations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lopes Jesus, A. J.; CQC, Faculty of Pharmacy, University of Coimbra, 3004-295 Coimbra; Reva, I., E-mail: reva@qui.uc.pt

    2016-03-28

    Conformational changes induced thermally or upon infrared excitation of matrix-isolated 6-methoxyindole were investigated. Narrowband near-infrared excitation of the first overtone of the N–H stretching vibration of each one of the two identified conformers is found to induce a selective large-scale conversion of the pumped conformer into the other one. This easily controllable bidirectional process consists in the intramolecular reorientation of the methoxy group and allowed a full assignment of the infrared spectra of the two conformers. Matrices with different conformational compositions prepared by narrow-band irradiations were subsequently used to investigate the effects of both thermal and broadband infrared excitations onmore » the conformational mixtures. Particular attention is given to the influence of the matrix medium (Ar vs. Xe) and conformational effects of exposition of the sample to the spectrometer light source during the measurements.« less

  7. Application of spatially modulated near-infrared structured light to study changes in optical properties of mouse brain tissue during heatstress.

    PubMed

    Shaul, Oren; Fanrazi-Kahana, Michal; Meitav, Omri; Pinhasi, Gad A; Abookasis, David

    2017-11-10

    Heat stress (HS) is a medical emergency defined by abnormally elevated body temperature that causes biochemical, physiological, and hematological changes. The goal of the present research was to detect variations in optical properties (absorption, reduced scattering, and refractive index coefficients) of mouse brain tissue during HS by using near-infrared (NIR) spatial light modulation. NIR spatial patterns with different spatial phases were used to differentiate the effects of tissue scattering from those of absorption. Decoupling optical scattering from absorption enabled the quantification of a tissue's chemical constituents (related to light absorption) and structural properties (related to light scattering). Technically, structured light patterns at low and high spatial frequencies of six wavelengths ranging between 690 and 970 nm were projected onto the mouse scalp surface while diffuse reflected light was recorded by a CCD camera positioned perpendicular to the mouse scalp. Concurrently to pattern projection, brain temperature was measured with a thermal camera positioned slightly off angle from the mouse head while core body temperature was monitored by thermocouple probe. Data analysis demonstrated variations from baseline measurements in a battery of intrinsic brain properties following HS.

  8. MEASUREMENTS OF THE MEAN DIFFUSE GALACTIC LIGHT SPECTRUM IN THE 0.95–1.65 μm BAND FROM CIBER

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arai, T.; Matsuura, S.; Sano, K.

    2015-06-10

    We report measurements of the diffuse galactic light (DGL) spectrum in the near-infrared, spanning the wavelength range 0.95–1.65 μm by the Cosmic Infrared Background ExpeRiment. Using the low-resolution spectrometer calibrated for absolute spectro-photometry, we acquired long-slit spectral images of the total diffuse sky brightness toward six high-latitude fields spread over four sounding rocket flights. To separate the DGL spectrum from the total sky brightness, we correlated the spectral images with a 100 μm intensity map, which traces the dust column density in optically thin regions. The measured DGL spectrum shows no resolved features and is consistent with other DGL measurementsmore » in the optical and at near-infrared wavelengths longer than 1.8 μm. Our result implies that the continuum is consistently reproduced by models of scattered starlight in the Rayleigh scattering regime with a few large grains.« less

  9. The Andromeda Optical and Infrared Disk Survey

    NASA Astrophysics Data System (ADS)

    Sick, J.; Courteau, S.; Cuillandre, J.-C.

    2014-03-01

    The Andromeda Optical and Infrared Disk Survey has mapped M31 in u* g' r' i' JKs wavelengths out to R = 40 kpc using the MegaCam and WIRCam wide-field cameras on the Canada-France-Hawaii Telescope. Our survey is uniquely designed to simultaneously resolve stars while also carefully reproducing the surface brightness of M31, allowing us to study M31's global structure in the context of both resolved stellar populations and spectral energy distributions. We use the Elixir-LSB method to calibrate the optical u* g' r' i' images by building real-time maps of the sky background with sky-target nodding. These maps are stable to μg ≲ 28.5 mag arcsec-2 and reveal warps in the outer M31 disk in surface brightness. The equivalent WIRCam mapping in the near-infrared uses a combination of sky-target nodding and image-to-image sky offset optimization to produce stable surface brightnesses. This study enables a detailed analysis of the systematics of spectral energy distribution fitting with near-infrared bands where asymptotic giant branch stars impose a significant, but ill-constrained, contribution to the near-infrared light of a galaxy. Here we present panchromatic surface brightness maps and initial results from our near-infrared resolved stellar catalog.

  10. Superfast Near-Infrared Light-Driven Polymer Multilayer Rockets.

    PubMed

    Wu, Zhiguang; Si, Tieyan; Gao, Wei; Lin, Xiankun; Wang, Joseph; He, Qiang

    2016-02-03

    A gold nanoshell-functionalized polymer multilayer nanorocket performs self-propulsion upon the irradiation with NIR light in the absence of chemical fuel. Theoretical simulations reveal that the NIR light-triggered self-thermophoresis drives the propulsion of the nanorocket. The nanorocket also displays -efficient NIR light-triggered propulsion in -biofluids and thus holds considerable promise for various potential biomedical applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Improved real-time imaging spectrometer

    NASA Technical Reports Server (NTRS)

    Lambert, James L. (Inventor); Chao, Tien-Hsin (Inventor); Yu, Jeffrey W. (Inventor); Cheng, Li-Jen (Inventor)

    1993-01-01

    An improved AOTF-based imaging spectrometer that offers several advantages over prior art AOTF imaging spectrometers is presented. The ability to electronically set the bandpass wavelength provides observational flexibility. Various improvements in optical architecture provide simplified magnification variability, improved image resolution and light throughput efficiency and reduced sensitivity to ambient light. Two embodiments of the invention are: (1) operation in the visible/near-infrared domain of wavelength range 0.48 to 0.76 microns; and (2) infrared configuration which operates in the wavelength range of 1.2 to 2.5 microns.

  12. A Data-driven Study of RR Lyrae Near-IR Light Curves: Principal Component Analysis, Robust Fits, and Metallicity Estimates

    NASA Astrophysics Data System (ADS)

    Hajdu, Gergely; Dékány, István; Catelan, Márcio; Grebel, Eva K.; Jurcsik, Johanna

    2018-04-01

    RR Lyrae variables are widely used tracers of Galactic halo structure and kinematics, but they can also serve to constrain the distribution of the old stellar population in the Galactic bulge. With the aim of improving their near-infrared photometric characterization, we investigate their near-infrared light curves, as well as the empirical relationships between their light curve and metallicities using machine learning methods. We introduce a new, robust method for the estimation of the light-curve shapes, hence the average magnitudes of RR Lyrae variables in the K S band, by utilizing the first few principal components (PCs) as basis vectors, obtained from the PC analysis of a training set of light curves. Furthermore, we use the amplitudes of these PCs to predict the light-curve shape of each star in the J-band, allowing us to precisely determine their average magnitudes (hence colors), even in cases where only one J measurement is available. Finally, we demonstrate that the K S-band light-curve parameters of RR Lyrae variables, together with the period, allow the estimation of the metallicity of individual stars with an accuracy of ∼0.2–0.25 dex, providing valuable chemical information about old stellar populations bearing RR Lyrae variables. The methods presented here can be straightforwardly adopted for other classes of variable stars, bands, or for the estimation of other physical quantities.

  13. The infrared counterpart of the eclipsing X-ray binary HO253 + 193

    NASA Technical Reports Server (NTRS)

    Zuckerman, B.; Becklin, E. E.; Mclean, I. S.; Patterson, Joseph

    1992-01-01

    We report the identification of the infrared counterpart of the pulsating X-ray source HO253 + 193. It is a highly reddened star varying in K light with a period near 3 hr, but an apparent even-odd effect in the light curve implies that the true period is 6.06 hr. Together with the recent report of X-ray eclipses at the latter period, this establishes the close binary nature of the source. Infrared minimum occurs at X-ray minimum, certifying that the infrared variability arises from the tidal distortion of the lobe-filling secondary. The absence of a point source at radio wavelengths, plus the distance derived from the infrared data, suggests that the binary system is accidentally located behind the dense core of the molecular cloud Lynds 1457. The eclipses and pulsations in the X-ray light curve, coupled with the hard X-ray spectrum and low luminosity, demonstrate that HO253 + 193 contains an accreting magnetic white dwarf, and hence belongs to the 'DQ Herculis' class of cataclysmic variables.

  14. SN 2012fr: Ultraviolet, Optical, and Near-infrared Light Curves of a Type Ia Supernova Observed within a Day of Explosion

    NASA Astrophysics Data System (ADS)

    Contreras, Carlos; Phillips, M. M.; Burns, Christopher R.; Piro, Anthony L.; Shappee, B. J.; Stritzinger, Maximilian D.; Baltay, C.; Brown, Peter J.; Conseil, Emmanuel; Klotz, Alain; Nugent, Peter E.; Turpin, Damien; Parker, Stu; Rabinowitz, D.; Hsiao, Eric Y.; Morrell, Nidia; Campillay, Abdo; Castellón, Sergio; Corco, Carlos; González, Consuelo; Krisciunas, Kevin; Serón, Jacqueline; Tucker, Brad E.; Walker, E. S.; Baron, E.; Cain, C.; Childress, Michael J.; Folatelli, Gastón; Freedman, Wendy L.; Hamuy, Mario; Hoeflich, P.; Persson, S. E.; Scalzo, Richard; Schmidt, Brian; Suntzeff, Nicholas B.

    2018-05-01

    We present detailed ultraviolet, optical, and near-infrared light curves of the Type Ia supernova (SN) 2012fr, which exploded in the Fornax cluster member NGC 1365. These precise high-cadence light curves provide a dense coverage of the flux evolution from ‑12 to +140 days with respect to the epoch of B-band maximum ({t}{B\\max }). Supplementary imaging at the earliest epochs reveals an initial slow and nearly linear rise in luminosity with a duration of ∼2.5 days, followed by a faster rising phase that is well reproduced by an explosion model with a moderate amount of 56Ni mixing in the ejecta. From our analysis of the light curves, we conclude that: (i) the explosion occurred <22 hr before the first detection of the supernova, (ii) the rise time to peak bolometric (λ > 1800 Å) luminosity was 16.5 ± 0.6 days, (iii) the supernova suffered little or no host-galaxy dust reddening, (iv) the peak luminosity in both the optical and near-infrared was consistent with the bright end of normal Type Ia diversity, and (v) 0.60 ± 0.15 M ⊙ of 56Ni was synthesized in the explosion. Despite its normal luminosity, SN 2012fr displayed unusually prevalent high-velocity Ca II and Si II absorption features, and a nearly constant photospheric velocity of the Si II λ6355 line at ∼12,000 {km} {{{s}}}-1 that began ∼5 days before {t}{B\\max }. We also highlight some of the other peculiarities in the early phase photometry and the spectral evolution. SN 2012fr also adds to a growing number of Type Ia supernovae that are hosted by galaxies with direct Cepheid distance measurements. This paper includes data gathered with the 6.5 m Magellan Baade Telescope, located at Las Campanas Observatory, Chile.

  15. Transcranial light-emitting diode therapy for neuropsychological improvement after traumatic brain injury: a new perspective for diffuse axonal lesion management

    PubMed Central

    dos Santos, João Gustavo Rocha Peixoto; Paiva, Wellingson Silva; Teixeira, Manoel Jacobsen

    2018-01-01

    The cost of traumatic brain injury (TBI) for public health policies is undeniable today. Even patients who suffer from mild TBI may persist with cognitive symptoms weeks after the accident. Most of them show no lesion in computed tomography or conventional magnetic resonance imaging, but microstructural white matter abnormalities (diffuse axonal lesion) can be found in diffusion tensor imaging. Different brain networks work together to form an important part of the cognition process, and they can be affected by TBI. The default mode network (DMN) plays an important central role in normal brain activities, presenting greater relative deactivation during more cognitively demanding tasks. After deactivation, it allows a distinct network to activate. This network (the central executive network) acts mainly during tasks involving executive functions. The salience network is another network necessary for normal executive function, and its activation leads to deactivation of the DMN. The use of red or near-infrared (NIR) light to stimulate or regenerate tissue is known as photobiomodulation. It was discovered that NIR (wavelength 800–900 nm) and red (wavelength 600 nm) light-emitting diodes (LEDs) are able to penetrate through scalp and skull and have the potential to improve the subnormal, cellular activity of compromised brain tissue. Based on this, different experimental and clinical studies were done to test LED therapy for TBI, and promising results were found. It leads us to consider developing different approaches to maximize the positive effects of this therapy and improve the quality of life of TBI patients. PMID:29731669

  16. Transcranial light-emitting diode therapy for neuropsychological improvement after traumatic brain injury: a new perspective for diffuse axonal lesion management.

    PubMed

    Dos Santos, João Gustavo Rocha Peixoto; Paiva, Wellingson Silva; Teixeira, Manoel Jacobsen

    2018-01-01

    The cost of traumatic brain injury (TBI) for public health policies is undeniable today. Even patients who suffer from mild TBI may persist with cognitive symptoms weeks after the accident. Most of them show no lesion in computed tomography or conventional magnetic resonance imaging, but microstructural white matter abnormalities (diffuse axonal lesion) can be found in diffusion tensor imaging. Different brain networks work together to form an important part of the cognition process, and they can be affected by TBI. The default mode network (DMN) plays an important central role in normal brain activities, presenting greater relative deactivation during more cognitively demanding tasks. After deactivation, it allows a distinct network to activate. This network (the central executive network) acts mainly during tasks involving executive functions. The salience network is another network necessary for normal executive function, and its activation leads to deactivation of the DMN. The use of red or near-infrared (NIR) light to stimulate or regenerate tissue is known as photobiomodulation. It was discovered that NIR (wavelength 800-900 nm) and red (wavelength 600 nm) light-emitting diodes (LEDs) are able to penetrate through scalp and skull and have the potential to improve the subnormal, cellular activity of compromised brain tissue. Based on this, different experimental and clinical studies were done to test LED therapy for TBI, and promising results were found. It leads us to consider developing different approaches to maximize the positive effects of this therapy and improve the quality of life of TBI patients.

  17. Near infrared spatial frequency domain fluorescence imaging of tumor phantoms containing erythrocyte-derived optical nanoplatforms

    NASA Astrophysics Data System (ADS)

    Burns, Joshua M.; Schaefer, Elise; Anvari, Bahman

    2018-02-01

    Light-activated theranostic constructs provide a multi-functional platform for optical imaging and phototherapeutic applications. Our group has engineered nano-sized vesicles derived from erythrocytes that encapsulate the FDAapproved near infrared (NIR) absorber indocyanine green (ICG). We refer to these constructs as NIR erythrocytemimicking transducers (NETs). Once photo-excited by NIR light these constructs can transduce the photons energy to emit fluorescence, generate heat, or induce chemical reactions. In this study, we investigated fluorescence imaging of NETs embedded within tumor phantoms using spatial frequency domain imaging (SFDI). Using SFDI, we were able to fluorescently image simulated tumors doped with different concentration of NETs. These preliminary results suggest that NETs can be used in conjunction with SFDI for potential tumor imaging applications.

  18. Low efficiency upconversion nanoparticles for high-resolution coalignment of near-infrared and visible light paths on a light microscope

    PubMed Central

    Sundaramoorthy, Sriramkumar; Badaracco, Adrian Garcia; Hirsch, Sophia M.; Park, Jun Hong; Davies, Tim; Dumont, Julien; Shirasu-Hiza, Mimi; Kummel, Andrew C.; Canman, Julie C.

    2017-01-01

    The combination of near infrared (NIR) and visible wavelengths in light microscopy for biological studies is increasingly common. For example, many fields of biology are developing the use of NIR for optogenetics, in which an NIR laser induces a change in gene expression and/or protein function. One major technical barrier in working with both NIR and visible light on an optical microscope is obtaining their precise coalignment at the imaging plane position. Photon upconverting particles (UCPs) can bridge this gap as they are excited by NIR light but emit in the visible range via an anti-Stokes luminescence mechanism. Here, two different UCPs have been identified, high-efficiency micro540-UCPs and lower efficiency nano545-UCPs, that respond to NIR light and emit visible light with high photostability even at very high NIR power densities (>25,000 Suns). Both of these UCPs can be rapidly and reversibly excited by visible and NIR light and emit light at visible wavelengths detectable with standard emission settings used for Green Fluorescent Protein (GFP), a commonly used genetically-encoded fluorophore. However, the high efficiency micro540-UCPs were suboptimal for NIR and visible light coalignment, due to their larger size and spatial broadening from particle-to-particle energy transfer consistent with a long lived excited state and saturated power dependence. In contrast, the lower efficiency nano-UCPs were superior for precise coalignment of the NIR beam with the visible light path (~2 µm versus ~8 µm beam broadening respectively) consistent with limited particle-to-particle energy transfer, superlinear power dependence for emission, and much smaller particle size. Furthermore, the nano-UCPs were superior to a traditional two-camera method for NIR and visible light path alignment in an in vivo Infrared-Laser-Evoked Gene Operator (IR-LEGO) optogenetics assay in the budding yeast S. cerevisiae. In summary, nano-UCPs are powerful new tools for coaligning NIR and visible light paths on a light microscope. PMID:28221018

  19. Plant tissue and the color infrared record

    NASA Technical Reports Server (NTRS)

    Pease, R. W.

    1969-01-01

    Green plant tissue should not be considered as having a uniguely high near-infrared reflectance but rather a low visual reflectance. Leaf tissue without chloroplasts appears to reflect well both visual and near infrared wavelengths. The sensitometry of color infrared film is such that a spectral imbalance strongly favoring infrared reflection is necessary to yield a red record. It is the absorption of visual light by chlorophyll that creates the imbalance that makes the typical red record for plants possible. Reflectance measurements of leaves that have been chemically blanched or which have gone into natural chloride decline strongly suggests that it is the rise in the visual reflectance that is most important in removing the imbalance and degrading the red CIR record. The role of water in leaves appears to be that of rendering epidermal membranes translucent so that the underlying chlorophyll controls the reflection rather than the leaf surface.

  20. Doxorubicin Loaded Chitosan-W18 O49 Hybrid Nanoparticles for Combined Photothermal-Chemotherapy.

    PubMed

    Yuan, Shanmei; Hua, Jisong; Zhou, Yinyin; Ding, Yin; Hu, Yong

    2017-08-01

    Combined treatment is more effective than single treatment against most forms of cancer. In this work, doxorubicin loaded chitosan-W 18 O 49 nanoparticles combined with the photothermal therapy and chemotherapy are fabricated through the electrostatic interaction between positively charged chitosan and negatively charged W 18 O 49 nanoparticles. The in vitro and in vivo behaviors of these nanoparticles are examined by dynamic light scattering, transmission electron microscopy, cytotoxicity, near-infrared fluorescence imaging, and tumor growth inhibition experiment. These nanoparticles have a mean size around 110 nm and show a pH sensitive drug release behavior. After irradiation by the 980 nm laser, these nanoparticles show more pronounced cytotoxicity against HeLa cells than that of free doxorubicin or photothermal therapy alone. The in vivo experiments confirm that their antitumor ability is significantly improved, resulting in superior efficiency in impeding tumor growth and extension of the lifetime of mice. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. A photoactivable multi-inhibitor nanoliposome for tumour control and simultaneous inhibition of treatment escape pathways

    NASA Astrophysics Data System (ADS)

    Spring, Bryan Q.; Bryan Sears, R.; Zheng, Lei Zak; Mai, Zhiming; Watanabe, Reika; Sherwood, Margaret E.; Schoenfeld, David A.; Pogue, Brian W.; Pereira, Stephen P.; Villa, Elizabeth; Hasan, Tayyaba

    2016-04-01

    Nanoscale drug delivery vehicles can facilitate multimodal therapies of cancer by promoting tumour-selective drug release. However, few are effective because cancer cells develop ways to resist and evade treatment. Here, we introduce a photoactivable multi-inhibitor nanoliposome (PMIL) that imparts light-induced cytotoxicity in synchrony with a photoinitiated and sustained release of inhibitors that suppress tumour regrowth and treatment escape signalling pathways. The PMIL consists of a nanoliposome doped with a photoactivable chromophore (benzoporphyrin derivative, BPD) in the lipid bilayer, and a nanoparticle containing cabozantinib (XL184)—a multikinase inhibitor—encapsulated inside. Near-infrared tumour irradiation, following intravenous PMIL administration, triggers photodynamic damage of tumour cells and microvessels, and simultaneously initiates release of XL184 inside the tumour. A single PMIL treatment achieves prolonged tumour reduction in two mouse models and suppresses metastatic escape in an orthotopic pancreatic tumour model. The PMIL offers new prospects for cancer therapy by enabling spatiotemporal control of drug release while reducing systemic drug exposure and associated toxicities.

  2. A core/satellite multifunctional nanotheranostic for in vivo imaging and tumor eradication by radiation/photothermal synergistic therapy.

    PubMed

    Xiao, Qingfeng; Zheng, Xiangpeng; Bu, Wenbo; Ge, Weiqiang; Zhang, Shengjian; Chen, Feng; Xing, Huaiyong; Ren, Qingguo; Fan, Wenpei; Zhao, Kuaile; Hua, Yanqing; Shi, Jianlin

    2013-09-04

    To integrate photothermal ablation (PTA) with radiotherapy (RT) for improved cancer therapy, we constructed a novel multifunctional core/satellite nanotheranostic (CSNT) by decorating ultrasmall CuS nanoparticles onto the surface of a silica-coated rare earth upconversion nanoparticle. These CSNTs could not only convert near-infrared light into heat for effective thermal ablation but also induce a highly localized radiation dose boost to trigger substantially enhanced radiation damage both in vitro and in vivo. With the synergistic interaction between PTA and the enhanced RT, the tumor could be eradicated without visible recurrence in 120 days. Notably, hematological analysis and histological examination unambiguously revealed their negligible toxicity to the mice within a month. Moreover, the novel CSNTs facilitate excellent upconversion luminescence/magnetic resonance/computer tomography trimodal imagings. This multifunctional nanocomposite is believed to be capable of playing a vital role in future oncotherapy by the synergistic effects between enhanced RT and PTA under the potential trimodal imaging guidance.

  3. Optical Imaging in Breast Cancer Diagnosis: The Next Evolution

    PubMed Central

    Ruibal, Alvaro

    2012-01-01

    Breast cancer is one of the most common cancers among the population of the Western world. Diagnostic methods include mammography, ultrasound, and magnetic resonance; meanwhile, nuclear medicine techniques have a secondary role, being useful in regional assessment and therapy followup. Optical imaging is a very promising imaging technique that uses near-infrared light to assess optical properties of tissues and is expected to play an important role in breast cancer detection. Optical breast imaging can be performed by intrinsic breast tissue contrast alone (hemoglobin, water, and lipid content) or with the use of exogenous fluorescent probes that target specific molecules for breast cancer. Major advantages of optical imaging are that it does not use any radioactive components, very high sensitivity, relatively inexpensive, easily accessible, and the potential to be combined in a multimodal approach with other technologies such as mammography, ultrasound, MRI, and positron emission tomography. Moreover, optical imaging agents could, potentially, be used as “theranostics,” combining the process of diagnosis and therapy. PMID:23304141

  4. Topological insulator bismuth selenide as a theranostic platform for simultaneous cancer imaging and therapy.

    PubMed

    Li, Juan; Jiang, Fei; Yang, Bo; Song, Xiao-Rong; Liu, Yan; Yang, Huang-Hao; Cao, Dai-Rong; Shi, Wen-Rong; Chen, Guo-Nan

    2013-01-01

    Employing theranostic nanoparticles, which combine both therapeutic and diagnostic capabilities in one dose, has promise to propel the biomedical field toward personalized medicine. Here we investigate the theranostic properties of topological insulator bismuth selenide (Bi2Se3) in in vivo and in vitro system for the first time. We show that Bi2Se3 nanoplates can absorb near-infrared (NIR) laser light and effectively convert laser energy into heat. Such photothermal conversion property may be due to the unique physical properties of topological insulators. Furthermore, localized and irreversible photothermal ablation of tumors in the mouse model is successfully achieved by using Bi2Se3 nanoplates and NIR laser irradiation. In addition, we also demonstrate that Bi2Se3 nanoplates exhibit strong X-ray attenuation and can be utilized for enhanced X-ray computed tomography imaging of tumor tissue in vivo. This study highlights Bi2Se3 nanoplates could serve as a promising platform for cancer diagnosis and therapy.

  5. Optical clearing of melanoma in vivo: characterization by diffuse reflectance spectroscopy and optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Pires, Layla; Demidov, Valentin; Vitkin, I. Alex; Bagnato, Vanderlei; Kurachi, Cristina; Wilson, Brian C.

    2016-08-01

    Melanoma is the most aggressive type of skin cancer, with significant risk of fatality. Due to its pigmentation, light-based imaging and treatment techniques are limited to near the tumor surface, which is inadequate, for example, to evaluate the microvascular density that is associated with prognosis. White-light diffuse reflectance spectroscopy (DRS) and near-infrared optical coherence tomography (OCT) were used to evaluate the effect of a topically applied optical clearing agent (OCA) in melanoma in vivo and to image the microvascular network. DRS was performed using a contact fiber optic probe in the range from 450 to 650 nm. OCT imaging was performed using a swept-source system at 1310 nm. The OCT image data were processed using speckle variance and depth-encoded algorithms. Diffuse reflectance signals decreased with clearing, dropping by ˜90% after 45 min. OCT was able to image the microvasculature in the pigmented melanoma tissue with good spatial resolution up to a depth of ˜300 μm without the use of OCA; improved contrast resolution was achieved with optical clearing to a depth of ˜750 μm in tumor. These findings are relevant to potential clinical applications in melanoma, such as assessing prognosis and treatment responses. Optical clearing may also facilitate the use of light-based treatments such as photodynamic therapy.

  6. Comparison of Two Methodologies for Calibrating Satellite Instruments in the Visible and Near-Infrared

    NASA Technical Reports Server (NTRS)

    Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Butler, James J.; Schwarting, Thomas; Turpie, Kevin; Moyer, David; DeLuccia, Frank; Moeller, Christopher

    2015-01-01

    Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field-of-view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as lamp-illuminated integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered.

  7. Cyclic Colour Change in the Bearded Dragon Pogona vitticeps under Different Photoperiods

    PubMed Central

    Fan, Marie; Stuart-Fox, Devi; Cadena, Viviana

    2014-01-01

    The ability to change colour rapidly is widespread among ectotherms and has various functions including camouflage, communication and thermoregulation. The process of colour change can occur as an aperiodic event or be rhythmic, induced by cyclic environmental factors or regulated by internal oscillators. Despite the importance of colour change in reptile ecology, few studies have investigated the occurrence of a circadian rhythm in lizard pigmentation. Additionally, although colour change also entails changes in near-infrared reflectance, which may affect thermoregulation, little research has examined this part of the spectrum. We tested whether the bearded dragon lizard, Pogona vitticeps, displays an endogenous circadian rhythm in pigmentation changes that could be entrained by light/dark (LD) cycles and how light affected the relative change in reflectance in both ultraviolet-visible and near-infrared spectra. We subjected 11 lizards to four photoperiodic regimens: LD 12∶12; LD 6∶18; LD 18∶6 and DD; and measured their dorsal skin reflectance at 3-hour intervals for 72 hours after a habituation period. A proportion of lizards displayed a significant rhythm under constant darkness, with maximum reflectance occurring in the subjective night. This endogenous rhythm synchronised to the different artificial LD cycles, with maximum reflectance occurring during dark phases, but did not vary in amplitude. In addition, the total ultraviolet-visible reflectance in relation to the total near-infrared reflectance was significantly higher during dark phases than during light phases. We conclude that P. vitticeps exhibits a circadian pigmentation rhythm of constant amplitude, regulated by internal oscillators and that can be entrained by light/dark cycles. PMID:25354192

  8. Cyclic colour change in the bearded dragon Pogona vitticeps under different photoperiods.

    PubMed

    Fan, Marie; Stuart-Fox, Devi; Cadena, Viviana

    2014-01-01

    The ability to change colour rapidly is widespread among ectotherms and has various functions including camouflage, communication and thermoregulation. The process of colour change can occur as an aperiodic event or be rhythmic, induced by cyclic environmental factors or regulated by internal oscillators. Despite the importance of colour change in reptile ecology, few studies have investigated the occurrence of a circadian rhythm in lizard pigmentation. Additionally, although colour change also entails changes in near-infrared reflectance, which may affect thermoregulation, little research has examined this part of the spectrum. We tested whether the bearded dragon lizard, Pogona vitticeps, displays an endogenous circadian rhythm in pigmentation changes that could be entrained by light/dark (LD) cycles and how light affected the relative change in reflectance in both ultraviolet-visible and near-infrared spectra. We subjected 11 lizards to four photoperiodic regimens: LD 12:12; LD 6:18; LD 18:6 and DD; and measured their dorsal skin reflectance at 3-hour intervals for 72 hours after a habituation period. A proportion of lizards displayed a significant rhythm under constant darkness, with maximum reflectance occurring in the subjective night. This endogenous rhythm synchronised to the different artificial LD cycles, with maximum reflectance occurring during dark phases, but did not vary in amplitude. In addition, the total ultraviolet-visible reflectance in relation to the total near-infrared reflectance was significantly higher during dark phases than during light phases. We conclude that P. vitticeps exhibits a circadian pigmentation rhythm of constant amplitude, regulated by internal oscillators and that can be entrained by light/dark cycles.

  9. Comparison of two methodologies for calibrating satellite instruments in the visible and near infrared

    PubMed Central

    Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Butler, James J.; Schwarting, Thomas; Moyer, David; Turpie, Kevin; DeLuccia, Frank; Moeller, Christopher

    2016-01-01

    Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field-of-view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered. PMID:26836861

  10. Near-Infrared Fluorescence-Enhanced Optical Tomography

    PubMed Central

    2016-01-01

    Fluorescence-enhanced optical imaging using near-infrared (NIR) light developed for in vivo molecular targeting and reporting of cancer provides promising opportunities for diagnostic imaging. The current state of the art of NIR fluorescence-enhanced optical tomography is reviewed in the context of the principle of fluorescence, the different measurement schemes employed, and the mathematical tools established to tomographically reconstruct the fluorescence optical properties in various tissue domains. Finally, we discuss the recent advances in forward modeling and distributed memory parallel computation to provide robust, accurate, and fast fluorescence-enhanced optical tomography. PMID:27803924

  11. Near-Infrared Fluorescence-Enhanced Optical Tomography.

    PubMed

    Zhu, Banghe; Godavarty, Anuradha

    2016-01-01

    Fluorescence-enhanced optical imaging using near-infrared (NIR) light developed for in vivo molecular targeting and reporting of cancer provides promising opportunities for diagnostic imaging. The current state of the art of NIR fluorescence-enhanced optical tomography is reviewed in the context of the principle of fluorescence, the different measurement schemes employed, and the mathematical tools established to tomographically reconstruct the fluorescence optical properties in various tissue domains. Finally, we discuss the recent advances in forward modeling and distributed memory parallel computation to provide robust, accurate, and fast fluorescence-enhanced optical tomography.

  12. A dual-modal magnetic nanoparticle probe for preoperative and intraoperative mapping of sentinel lymph nodes by magnetic resonance and near infrared fluorescence imaging

    PubMed Central

    Zhou, Zhengyang; Chen, Hongwei; Lipowska, Malgorzata; Wang, Liya; Yu, Qiqi; Yang, Xiaofeng; Tiwari, Diana; Yang, Lily; Mao, Hui

    2016-01-01

    The ability to reliably detect sentinel lymph nodes for sentinel lymph node biopsy and lymphadenectomy is important in clinical management of patients with metastatic cancers. However, the traditional sentinel lymph node mapping with visible dyes is limited by the penetration depth of light and fast clearance of the dyes. On the other hand, sentinel lymph node mapping with radionucleotide technique has intrinsically low spatial resolution and does not provide anatomic details in the sentinel lymph node mapping procedure. This work reports the development of a dual modality imaging probe with magnetic resonance and near infrared imaging capabilities for sentinel lymph node mapping using magnetic iron oxide nanoparticles (10 nm core size) conjugated with a near infrared molecule with emission at 830 nm. Accumulation of magnetic iron oxide nanoparticles in sentinel lymph nodes leads to strong T2 weighted magnetic resonance imaging contrast that can be potentially used for preoperative localization of sentinel lymph nodes, while conjugated near infrared molecules provide optical imaging tracking of lymph nodes with a high signal to background ratio. The new magnetic nanoparticle based dual imaging probe exhibits a significant longer lymph node retention time. Near infrared signals from nanoparticle conjugated near infrared dyes last up to 60 min in sentinel lymph node compared to that of 25 min for the free near infrared dyes in a mouse model. Furthermore, axillary lymph nodes, in addition to sentinel lymph nodes, can be also visualized with this probe, given its slow clearance and sufficient sensitivity. Therefore, this new dual modality imaging probe with the tissue penetration and sensitive detection of sentinel lymph nodes can be applied for preoperative survey of lymph nodes with magnetic resonance imaging and allows intraoperative sentinel lymph node mapping using near infrared optical devices. PMID:23812946

  13. Mind-controlled transgene expression by a wireless-powered optogenetic designer cell implant.

    PubMed

    Folcher, Marc; Oesterle, Sabine; Zwicky, Katharina; Thekkottil, Thushara; Heymoz, Julie; Hohmann, Muriel; Christen, Matthias; Daoud El-Baba, Marie; Buchmann, Peter; Fussenegger, Martin

    2014-11-11

    Synthetic devices for traceless remote control of gene expression may provide new treatment opportunities in future gene- and cell-based therapies. Here we report the design of a synthetic mind-controlled gene switch that enables human brain activities and mental states to wirelessly programme the transgene expression in human cells. An electroencephalography (EEG)-based brain-computer interface (BCI) processing mental state-specific brain waves programs an inductively linked wireless-powered optogenetic implant containing designer cells engineered for near-infrared (NIR) light-adjustable expression of the human glycoprotein SEAP (secreted alkaline phosphatase). The synthetic optogenetic signalling pathway interfacing the BCI with target gene expression consists of an engineered NIR light-activated bacterial diguanylate cyclase (DGCL) producing the orthogonal second messenger cyclic diguanosine monophosphate (c-di-GMP), which triggers the stimulator of interferon genes (STING)-dependent induction of synthetic interferon-β promoters. Humans generating different mental states (biofeedback control, concentration, meditation) can differentially control SEAP production of the designer cells in culture and of subcutaneous wireless-powered optogenetic implants in mice.

  14. Photoswitchable non-fluorescent thermochromic dye-nanoparticle hybrid probes

    PubMed Central

    Harrington, Walter N.; Haji, Mwafaq R.; Galanzha, Ekaterina I.; Nedosekin, Dmitry A.; Nima, Zeid A.; Watanabe, Fumiya; Ghosh, Anindya; Biris, Alexandru S.; Zharov, Vladimir P.

    2016-01-01

    Photoswitchable fluorescent proteins with controllable light–dark states and spectral shifts in emission in response to light have led to breakthroughs in the study of cell biology. Nevertheless, conventional photoswitching is not applicable for weakly fluorescent proteins and requires UV light with low depth penetration in bio-tissue. Here we introduce a novel concept of photoswitchable hybrid probes consisting of thermochromic dye and absorbing nanoparticles, in which temperature-sensitive light–dark states and spectral shifts in absorption can be switched through controllable photothermal heating of doped nanoparticles. The proof-of-concept is demonstrated through the use of two different types of temperature-sensitive dyes doped with magnetic nanoparticles and reversibly photoswitched by a near-infrared laser. Photoacoustic imaging revealed the high contrast of these probes, which is sufficient for their visualization in cells and deep tissue. Our results suggest that these new photoswitchable multicolour probes can be used for multimodal cellular diagnostics and potentially for magnetic and photothermal therapy. PMID:27824110

  15. Photomedicine and Stem Cells; The Janus face of photodynamic therapy (PDT) to kill cancer stem cells, and photobiomodulation (PBM) to stimulate normal stem cells

    NASA Astrophysics Data System (ADS)

    Abrahamse, Heidi; Hamblin, Michael R.

    2017-12-01

    Janus, the ancient Roman god depicted with two faces is an appropriate metaphor for light therapy. In the right photodynamic therapy conditions, light is able to kill nearly anything that is living such as cancers, microorganisms, parasites, and more. On the opposite face, light of the correct wavelength and proper dose (photobiomodulation) can heal, regenerate, protect, revitalize and restore any kind of dead, damaged, stressed, dying, degenerating cells, tissue, or organ system. This book discusses both sides of Janus' face in regards to light therapy.

  16. The near-infrared continuum emission of visual reflection nebulae

    NASA Technical Reports Server (NTRS)

    Sellgren, K.

    1984-01-01

    In the past, reflection nebulae have provided an astrophysical laboratory well suited for the study of the reflection properties of interstellar dust grains at visual and ultraviolet wavelengths. The present investigation is concerned with observations which were begun with the objective to extend to near-infrared wavelengths the study of grains in reflection. Observations of three classical visual reflection nebulae were conducted in the wavelength range from 1.25 to 2.2 microns, taking into account NGC 7023, 2023, and 2068. All three nebulae were found to have similar near-infrared colors, despite widely different colors of their illuminating stars. The brightness level shown by two of the nebulae at 2.2 microns was too high to be easily accounted for on the basis of reflected light. Attention is given to a wide variety of possible emission mechanisms.

  17. Near- and far-field spectroscopic imaging investigation of resonant square-loop infrared metasurfaces.

    PubMed

    D' Archangel, Jeffrey; Tucker, Eric; Kinzel, Ed; Muller, Eric A; Bechtel, Hans A; Martin, Michael C; Raschke, Markus B; Boreman, Glenn

    2013-07-15

    Optical metamaterials have unique properties which result from geometric confinement of the optical conductivity. We developed a series of infrared metasurfaces based on an array of metallic square loop antennas. The far-field absorption spectrum can be designed with resonances across the infrared by scaling the geometric dimensions. We measure the amplitude and phase of the resonant mode as standing wave patterns within the square loops using scattering-scanning near-field optical microscopy (s-SNOM). Further, using a broad-band synchrotron-based FTIR microscope and s-SNOM at the Advanced Light Source, we are able to correlate far-field spectra to near-field modes of the metasurface as the resonance is tuned between samples. The results highlight the importance of multi-modal imaging for the design and characterization of optical metamaterials.

  18. Controlling plasmonic properties of epitaxial thin films of indium tin oxide in the near-infrared region

    NASA Astrophysics Data System (ADS)

    Kamakura, R.; Fujita, K.; Murai, S.; Tanaka, K.

    2015-06-01

    Epitaxial thin films of indium tin oxide (ITO) were grown on yttria-stabilized zirconia single-crystal substrates by using a pulsed laser deposition to examine their plasmonic properties. The dielectric function of ITO was characterized by spectroscopic ellipsometry. Through the concentration of SnO2 in the target, the carrier concentration in the films was modified, which directly leads to the tuning of the dielectric function in the near-infrared region. Variable-angle reflectance spectroscopy in the Kretschmann geometry shows the dip in the reflection spectrum of p-polarized light corresponding to the excitation of surface plasmon polaritions (SPPs) in the near-infrared region. The excitation wavelength of the SPPs was shifted with changing the dielectric functions of ITO, which is reproduced by the calculation using transfer matrix method.

  19. [Use of indocyanine green angiography in oncological and reconstructive breast surgery].

    PubMed

    Struk, S; Honart, J-F; Qassemyar, Q; Leymarie, N; Sarfati, B; Alkhashnam, H; Mazouni, C; Rimareix, F; Kolb, F

    2018-02-01

    The Indocyanine green (ICG) is a soluble dye that is eliminated by the liver and excreted in bile. When illuminated by an near-infrared light, the ICG emits fluorescence in the near-infrared spectrum, which can be captured by a near-infrared camera-handled device. In case of intravenous injection, ICG may be used as a marker of skin perfusion. In case of interstitial injection, it may be useful for lymphatic network mapping. In oncological and reconstructive breast surgery, ICG is used for sentinel lymph node identification, to predict mastectomy skin flap necrosis, to assess the perfusion of free flaps in autologous reconstruction and for diagnosis and treatment of upper limb secondary lymphedema. Intraoperative indocyanine green fluorescence might also be used to guide the excision of nonpalpable breast cancer. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. The Antineoplastic Activity of Photothermal Ablative Therapy with Targeted Gold Nanorods in an Orthotopic Urinary Bladder Cancer Model.

    PubMed

    Yang, Xiaoping; Su, Lih-Jen; La Rosa, Francisco G; Smith, Elizabeth Erin; Schlaepfer, Isabel R; Cho, Suehyun K; Kavanagh, Brian; Park, Wounjhang; Flaig, Thomas W

    2017-07-27

    Gold nanoparticles treated with near infrared (NIR) light can be heated preferentially, allowing for thermal ablation of targeted cells. The use of novel intravesical nanoparticle-directed therapy in conjunction with laser irradiation via a fiber optic cystoscope, represents a potential ablative treatment approach in patients with superficial bladder cancer. To examine the thermal ablative effect of epidermal growth factor receptor (EGFR)-directed gold nanorods irradiated with NIR light in an orthotopic urinary bladder cancer model. Gold nanorods linked to an anti-EGFR antibody (Conjugated gold NanoRods - CNR) were instilled into the bladder cavity of an orthotopic murine xenograft model with T24 bladder cancer cells expressing luciferase. NIR light was externally administered via an 808 nm diode laser. This treatment was repeated weekly for 4 weeks. The anti-cancer effect was monitored by an in vivo imaging system in a non-invasive manner, which was the primary outcome of our study. The optimal approach for an individual treatment was 2.1 W/cm 2 laser power for 30 seconds. Using this in vivo model, NIR light combined with CNR demonstrated a statistically significant reduction in tumor-associated bioluminescent activity ( n  = 16) compared to mice treated with laser alone ( n  = 14) at the end of the study ( p  = 0.035). Furthermore, the CNR+NIR light treatment significantly abrogated bioluminescence signals over a 6-week observation period, compared to pre-treatment levels ( p  = 0.045). Photothermal tumor ablation with EGFR-directed gold nanorods and NIR light proved effective and well tolerated in a murine in vivo model of urinary bladder cancer.

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