scholarly journals Comparative Study of the Optical and Heat Generation Properties of IR820 and Indocyanine Green

2012 ◽  
Vol 11 (2) ◽  
pp. 7290.2011.00031 ◽  
Author(s):  
Alicia Fernandez-Fernandez ◽  
Romila Manchanda ◽  
Tingjun Lei ◽  
Denny A. Carvajal ◽  
Yuan Tang ◽  
...  
Keyword(s):  
Indocyanine Green ◽  
Near Infrared ◽  
Experimental Models ◽  
Cyanine Dye ◽  
Laser Exposure ◽  
Fluorescence Signal ◽  
Thermal Generation ◽  
Significant Difference

Near-infrared (NIR) fluorophores are the focus of extensive research for combined molecular imaging and hyperthermia. In this study, we showed that the cyanine dye IR820 has optical and thermal generation properties similar to those of indocyanine green (ICG) but with improved in vitro and in vivo stability. The fluorescent emission of IR820 has a lower quantum yield than ICG but less dependence of the emission peak location on concentration. IR820 demonstrated degradation half-times approximately double those of ICG under all temperature and light conditions in aqueous solution. In hyperthermia applications, IR820 generated lower peak temperatures than ICG (4–9%) after 3-minute laser exposure. However, there was no significant difference in hyperthermia cytotoxicity, with both dyes causing significant cell growth inhibition at concentrations ≥ 5 μM. Fluorescent images of cells with 10 μM IR820 were similar to ICG images. In rats, IR820 resulted in a significantly more intense fluorescence signal and significantly higher organ dye content than for ICG 24 hours after intravenous dye administration ( p < .05). Our study shows that IR820 is a feasible agent in experimental models of imaging and hyperthermia and could be an alternative to ICG when greater stability, longer image collection times, or more predictable peak locations are desirable.

scholarly journals Indocyanine Green-Nexturastat A-PLGA Nanoparticles Combine Photothermal and Epigenetic Therapy for Melanoma

Nanomaterials ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 161 ◽  
Author(s):  
Debbie K. Ledezma ◽  
Preethi B. Balakrishnan ◽  
Juliana Cano-Mejia ◽  
Elizabeth E. Sweeney ◽  
Melissa Hadley ◽  
...  
Keyword(s):  
Indocyanine Green ◽  
Near Infrared ◽  
Specific Activity ◽  
Melanoma Cells ◽  
Plga Nanoparticles ◽  
Epigenetic Therapy ◽  
Photothermal Heating ◽  
Epigenetic Drug

In this study, we describe poly (lactic-co-glycolic) acid (PLGA)-based nanoparticles that combine photothermal therapy (PTT) with epigenetic therapy for melanoma. Specifically, we co-encapsulated indocyanine green (ICG), a PTT agent, and Nexturastat A (NextA), an epigenetic drug within PLGA nanoparticles (ICG-NextA-PLGA; INAPs). We hypothesized that combining PTT with epigenetic therapy elicits favorable cytotoxic and immunomodulatory responses that result in improved survival in melanoma-bearing mice. We utilized a nanoemulsion synthesis scheme to co-encapsulate ICG and NextA within stable and monodispersed INAPs. The INAPs exhibited concentration-dependent and near-infrared (NIR) laser power-dependent photothermal heating characteristics, and functioned as effective single-use agents for PTT of melanoma cells in vitro. The INAPs functioned as effective epigenetic therapy agents by inhibiting the expression of pan-histone deacetylase (HDAC) and HDAC6-specific activity in melanoma cells in vitro. When used for both PTT and epigenetic therapy in vitro, the INAPs increased the expression of co-stimulatory molecules and major histocompatibility complex (MHC) Class I in melanoma cells relative to controls. These advantages persisted in vivo in a syngeneic murine model of melanoma, where the combination therapy slowed tumor progression and improved median survival. These findings demonstrate the potential of INAPs as agents of PTT and epigenetic therapy for melanoma.

Abstract 305: Development of an Antidote-Controlled RNA Probe for Molecular Thrombi Imaging

2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Kady-Ann Steen-Burrell ◽  
Bethany Powell Gray ◽  
Bruce Sullenger
Keyword(s):  
Near Infrared ◽  
Surgical Complication ◽  
High Specificity ◽  
Fold Increase ◽  
Coagulation Factors ◽  
Fluorescence Signal ◽  
Rna Aptamer ◽  
Suitable Target

Vascular thrombosis is a major underlying factor in many cardiovascular diseases worldwide and is also a major post-surgical complication. Early detection and treatment of thrombi improves outcomes for patients since the responsiveness of thrombi to fibrinolytic treatment decreases with thrombus age. The serine protease thrombin plays a central role in thrombogenesis and remains associated with the thrombus thereby facilitating further activation of coagulation factors and platelets after initial clot formation. Therefore, targeting and imaging clot-bound thrombin may provide a way of distinguishing newly formed thrombi from older, constituted ones. The goal of this study was to determine whether a thrombin-binding RNA aptamer conjugated to a near-infrared fluorophore could detect clot-bound thrombin and if a complementary antidote oligonucleotide could remove clot-bound aptamer thereby creating a subtraction image. The thrombin-binding aptamer conjugate, Tog25t-AF680, was assessed for its in vitro binding capability to newly formed human plasma clots using fluorescence reflectance imaging. In comparison to a labeled non-binding control RNA, we observed a greater than 6-fold increase in near-infrared fluorescence (NIRF) target-to-background ratio (TBR) with Tog25t-AF680. Upon treatment with the antidote oligonucleotide (AO4), we observed an approximately 57% reduction in fluorescence signal after 10 minutes of incubation. Our results suggest that thrombin is a suitable target for imaging newly formed clots and that a RNA aptamer conjugate binds to clot-bound thrombin with high specificity. This thrombin-targeting near-infrared probe has the potential to be used as a diagnostic tool for arterial and venous thrombosis and may further advance our understanding of the role of thrombin in vivo.

scholarly journals Comparison of Five Near-Infrared Fluorescent Folate Conjugates in an Ovarian Cancer Model

2021 ◽  
Author(s):  
Elvira García de Jalón ◽  
Katrin Kleinmanns ◽  
Vibeke Fosse ◽  
Ben Davidson ◽  
Line Bjørge ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Near Infrared ◽  
Ex Vivo ◽  
Folate Receptor ◽  
Fluorescence Signal ◽  
Cancer Model ◽  
Target Binding ◽  
The Impact

Abstract Purpose Fluorescence imaging (FLI) using targeted near-infrared (NIR) conjugates aids the detection of tumour lesions pre- and intraoperatively. The optimisation of tumour visualisation and contrast is essential and can be achieved through high tumour-specificity and low background signal. However, the choice of fluorophore is recognised to alter biodistribution and clearance of conjugates and is therefore a determining factor in the specificity of target binding. Although ZW800-1, IRDye® 800CW and ICG are the most commonly employed NIR fluorophores in clinical settings, the fluorophore with optimal in vivo characteristics has yet to be determined. Therefore, we aimed to characterise the impact the choice of fluorophore has on the biodistribution, specificity and contrast, by comparing five different NIR fluorophores conjugated to folate, in an ovarian cancer model. Procedures ZW800-1, ZW800-1 Forte, IRDye® 800CW, ICG-OSu and an in-house synthesised Cy7 derivative were conjugated to folate through an ethylenediamine linker resulting in conjugates 1–5, respectively. The optical properties of all conjugates were determined by spectroscopy, the specificity was assessed in vitro by flow cytometry and FLI, and the biodistribution was studied in vivo and ex vivo in a subcutaneous Skov-3 ovarian cancer model. Results We demonstrated time- and receptor-dependent binding of folate conjugates in vitro and in vivo. Healthy tissue clearance characteristics and tumour-specific signal varied between conjugates 1–5. ZW800-1 Forte (2) revealed the highest contrast in folate receptor alpha (FRα)-positive xenografts and showed statistically significant target specificity. While conjugates 1, 2 and 3 are renally cleared, hepatobiliary excretion and no or very low accumulation in tumours was observed for 4 and 5. Conclusions The choice of fluorophore has a significant impact on the biodistribution and tumour contrast. ZW800-1 Forte (2) exhibited the best properties of those tested, with significant specific fluorescence signal.

scholarly journals Novel Rifampicin and Indocyanine Green Co-Loaded Perfluorocarbon Nanodroplets Provide Effective In Vivo Photo–Chemo–Probiotic Antimicrobility against Pathogen of Acne Vulgaris Cutibacterium acnes

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1095
Author(s):  
Kuang-Hung Hsiao ◽  
Chun-Ming Huang ◽  
Yu-Hsiang Lee
Keyword(s):  
Indocyanine Green ◽  
Staphylococcus Epidermidis ◽  
Near Infrared ◽  
Acne Vulgaris ◽  
Inhibition Zone ◽  
Inflammatory Protein ◽  
Cutibacterium Acnes ◽  
Macrophage Inflammatory Protein

Acne vulgaris is one of the most prevalent dermatological diseases among adolescents and is often associated with overgrowth of Cutibacterium acnes (C. acnes) in the pilosebaceous units. In this study, we aimed to develop novel rifampicin (RIF) and indocyanine green (ICG) co-loaded perfluorocarbon nanodroplets named RIPNDs which can simultaneously provide photo-, chemo-, and probiotic-antimicrobility, and explore their efficacy in treatment of C. acnes in vitro and in vivo. The RIPNDs were first characterized as being spherical in shape, with a size of 238.6 ± 7.51 nm and surface charge of −22.3 ± 3.5 mV. Then, the optimal dosages of Staphylococcus epidermidis–produced fermentation product medium (FPM) and RIPND were determined as 25% (v/v) and [RIF]/[ICG] = 3.8/20 μM, respectively, based on the analyses of inhibition zone and cytotoxicity in vitro. Through the in vivo study using C. acnes–inoculated mice, our data showed that the group treated with FPM followed by RIPNDs + near infrared (NIR) irradiation obtained the least granulocytes/macrophage-inflammatory protein 2 expression level in the epidermis, and showed a significantly lower microbial colony population compared to the groups treated with equal amount of RIF, FPM, RIPNDs, and/or combination of the above ± NIR. These results indicated that the RIPND-mediated photo–chemo–probiotic therapeutics was indeed able to rapidly suppress inflammatory response of the skin and provide a robust antibacterial effect against C. acnes with limited use of antibiotics. Taken altogether, we anticipate that the RIPND is highly potential for use in the clinical treatment of acne vulgaris.

scholarly journals Targeted Nanoparticles for Fluorescence Imaging of Folate Receptor Positive Tumors

Biomolecules ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1651
Author(s):  
Aimee J. Marko ◽  
Ballav M. Borah ◽  
Kevin E. Siters ◽  
Joseph R. Missert ◽  
Anurag Gupta ◽  
...  
Keyword(s):  
Folic Acid ◽  
Fluorescence Imaging ◽  
Near Infrared ◽  
Folate Receptor ◽  
Cyanine Dye ◽  
Target Specificity ◽  
Nir Fluorescence ◽  
Positive Breast Cancer

This report presents the synthesis and folate receptor target-specificity of amino-functionalized polyacrylamide nanoparticles (AFPAA NPs) for near-infrared (NIR) fluorescence imaging of cancer. For the synthesis of desired nano-constructs, the AFPAA NPs (hereafter referred to as NPs) were reacted with a NIR cyanine dye (CD) bearing carboxylic acid functionality by following our previously reported approach, and the resulting conjugate (NP-CD) on further reaction with folic acid (FA) resulted in a new nano-construct, FA-NP-CD, which demonstrated significantly higher uptake in folate receptor-positive breast cancer cells (KB+) and in folate receptor over-expressed tumors in vivo. The target-specificity of these nanoparticles was further confirmed by inhibition assay in folate receptor-positive (KB+) and -negative (HT-1080) cell lines. To show the advantages of polyacrylamide (PAA)-based NPs in folate receptor target-specificity, the CD used in preparing the FA-NP-CD construct was also reacted with folic acid alone and the synthetic conjugate (CD-FA) was also investigated for its target-specificity. Interestingly, in contrast to NPs (FA-NP-CD), the CD-FA conjugate did not show any significant in vitro or in vivo specificity toward folate receptors, showing the advantages of PAA-based nanotechnology in delivering the desired agent to tumor cells.

scholarly journals Dual-colour (near-infrared/visible) emitting annexin V for fluorescence imaging of tumour cell apoptosis in vitro and in vivo

RSC Advances ◽  
2020 ◽  
Vol 10 (63) ◽  
pp. 38244-38250
Author(s):  
Setsuko Tsuboi ◽  
Takashi Jin
Keyword(s):  
Tumor Cell ◽  
Indocyanine Green ◽  
Fluorescence Imaging ◽  
Cell Apoptosis ◽  
Near Infrared ◽  
Annexin V ◽  
Tumor Cell Apoptosis ◽  
Dual Colour

Indocyanine green labeled recombinant annexin V probes (ICG–EGFP–Annexin V and ICG–mPlum–Annexin V) were synthesized for near-infrared and visible fluorescence imaging of tumor cell apoptosis both in vitro and in vivo.

Neutralization of a Low Molecular Weight Heparin (LHN-1) and Conventional Heparin by Protamine Sulfate in Rats

1986 ◽  
Vol 56 (03) ◽  
pp. 318-322 ◽  
Author(s):  
V Diness ◽  
P B Østergaard
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight Heparin ◽  
Thrombus Formation ◽  
Experimental Models ◽  
Protamine Sulfate ◽  
Low Molecular Weight ◽  
Antithrombotic Effect ◽  
Higher Doses

SummaryThe neutralization of a low molecular weight heparin (LHN-1) and conventional heparin (CH) by protamine sulfate has been studied in vitro and in vivo. In vitro, the APTT activity of CH was completely neutralized in parallel with the anti-Xa activity. The APTT activity of LHN-1 was almost completely neutralized in a way similar to the APTT activity of CH, whereas the anti-Xa activity of LHN-1 was only partially neutralized.In vivo, CH 3 mg/kg and LHN-1 7.2 mg/kg was given intravenously in rats. The APTT and anti-Xa activities, after neutralization by protamine sulfate in vivo, were similar to the results in vitro. In CH treated rats no haemorrhagic effect in the rat tail bleeding test and no antithrombotic effect in the rat stasis model was found at a protamine sulfate to heparin ratio of about 1, which neutralized APTT and anti-Xa activities. In LHN-1 treated rats the haemorrhagic effect was neutralized when APTT was close to normal whereas higher doses of protamine sulfate were required for neutralization of the antithrombotic effect. This probably reflects the fact that in most experimental models higher doses of heparin are needed to induce bleeding than to prevent thrombus formation. Our results demonstrate that even if complete neutralization of APTT and anti-Xa activities were not seen in LHN-1 treated rats, the in vivo effects of LHN-1 could be neutralized as efficiently as those of conventional heparin. The large fall in blood pressure caused by high doses of protamine sulfate alone was prevented by the prior injection of LHN-1.

Antimicrobial peptides for the treatment of pulmonary tuberculosis, allies or foes?

2018 ◽  
Vol 24 (10) ◽  
pp. 1138-1147
Author(s):  
Bruno Rivas-Santiago ◽  
Flor Torres-Juarez
Keyword(s):  
Pulmonary Tuberculosis ◽  
Antimicrobial Peptides ◽  
Experimental Models ◽  
New Drugs ◽  
World Health ◽  
Public Health Issue ◽  
Health Organization ◽  
Drug Resistant Strains

Tuberculosis is an ancient disease that has become a serious public health issue in recent years, although increasing incidence has been controlled, deaths caused by Mycobacterium tuberculosis have been accentuated due to the emerging of multi-drug resistant strains and the comorbidity with diabetes mellitus and HIV. This situation is threatening the goals of World Health Organization (WHO) to eradicate tuberculosis in 2035. WHO has called for the creation of new drugs as an alternative for the treatment of pulmonary tuberculosis, among the plausible molecules that can be used are the Antimicrobial Peptides (AMPs). These peptides have demonstrated remarkable efficacy to kill mycobacteria in vitro and in vivo in experimental models, nevertheless, these peptides not only have antimicrobial activity but also have a wide variety of functions such as angiogenesis, wound healing, immunomodulation and other well-described roles into the human physiology. Therapeutic strategies for tuberculosis using AMPs must be well thought prior to their clinical use; evaluating comorbidities, family history and risk factors to other diseases, since the wide function of AMPs, they could lead to collateral undesirable effects.

Epithelial Organotypic Cultures: A Viable Model to Address Mechanisms of Carcinogenesis by Epitheliotropic Viruses

2018 ◽  
Vol 18 (4) ◽  
pp. 246-255 ◽  
Author(s):  
Lara Termini ◽  
Enrique Boccardo
Keyword(s):  
Three Dimensional ◽  
Cell Types ◽  
Experimental Models ◽  
Biological Research ◽  
Specific Gene ◽  
Specific Cell ◽  
Organotypic Cultures ◽  
Skin Physiology

In vitro culture of primary or established cell lines is one of the leading techniques in many areas of basic biological research. The use of pure or highly enriched cultures of specific cell types obtained from different tissues and genetics backgrounds has greatly contributed to our current understanding of normal and pathological cellular processes. Cells in culture are easily propagated generating an almost endless source of material for experimentation. Besides, they can be manipulated to achieve gene silencing, gene overexpression and genome editing turning possible the dissection of specific gene functions and signaling pathways. However, monolayer and suspension cultures of cells do not reproduce the cell type diversity, cell-cell contacts, cell-matrix interactions and differentiation pathways typical of the three-dimensional environment of tissues and organs from where they were originated. Therefore, different experimental animal models have been developed and applied to address these and other complex issues in vivo. However, these systems are costly and time consuming. Most importantly the use of animals in scientific research poses moral and ethical concerns facing a steadily increasing opposition from different sectors of the society. Therefore, there is an urgent need for the development of alternative in vitro experimental models that accurately reproduce the events observed in vivo to reduce the use of animals. Organotypic cultures combine the flexibility of traditional culture systems with the possibility of culturing different cell types in a 3D environment that reproduces both the structure and the physiology of the parental organ. Here we present a summarized description of the use of epithelial organotypic for the study of skin physiology, human papillomavirus biology and associated tumorigenesis.

scholarly journals The Effectiveness of Candidate Probiotic Bacteria to Control Vibriosis Disease

2017 ◽  
Vol 5 (2) ◽  
pp. 1
Author(s):  
Mulyati Mulyati ◽  
Suryati Suryati ◽  
Irfani Baga
Keyword(s):  
Survival Rate ◽  
Sea Water ◽  
Challenge Test ◽  
Probiotic Bacteria ◽  
Pathogenicity Test ◽  
Inhibitory Ability ◽  
Significant Difference ◽  
Portunid Crab

The study aims to isolate, characterize, and examine probiotic bacteria's inhibitory ability against Vibrio harveyi bacteria, both in-vitro and in vivo. Methods used in the study consist of 1) An Isolation of Candidate Probiotic Bacteria, 2) An Antagonistic Test of Candidate Probiotic Bacteria in vitro, 3) An Identification of Bacteria, 4) A Pathogenicity Test of Candidate Probiotic Bacteria, 5) An Antagonistic Test of Candidate Probiotic Bacteria against V. harveyi in vivo. According to the isolation of candidate probiotic bacteria, there are 18 isolated candidate probiotic. After being tested for its inhibitory ability in vitro, there are 8 isolates with zone of inhibition as follows: isolate MM 7 from intestine (22 mm), isolate MM 6 from intestine (12 mm), isolate MM 10 from sea water (10 mm), isolate MM 5 from intestine (9 mm), isolate MM 4 from intestine (8 mm), isolate MM 3 from intestine (7 mm), isolate MM 2.2 from intestine (7 mm), isolate MM 2.1 from intestine (7 mm). Eight genera of the candidate probiotic bacteria is derived from Portunid crab, they are Staphylococcus, Streptococcus, bacillus, vibrio, Alcaligenes, Lactobacillus, micrococcus. Before proceeding the V. harveyi bacterial challenge test in vivo, three potential isolates consisting of MM6, MM7 and MM10 as the probiotic bacteria are pathogenicity-tested against V. harveyi. The survival rate of Portunid crab on pathogenicity test using MM6, MM7 and MM10 generates 91.11-100%, while the control generates 100% survival rate. Variance analysis result through post-hoc Tukey's Honest Significant Difference (HSD) test at 95% confidence interval indicates that isolate MM7 and MM10 are significantly able to increase hatchling Portunid crab's survival rate.

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