scholarly journals SIMULTANEOUS IMAGING OF A lacZ-MARKED TUMOR AND MICROVASCULATURE MORPHOLOGY IN VIVO BY DUAL-WAVELENGTH PHOTOACOUSTIC MICROSCOPY

2008 ◽  
Vol 01 (02) ◽  
pp. 207-215 ◽  
Author(s):  
LI LI ◽  
HAO F. ZHANG ◽  
ROGER J. ZEMP ◽  
KONSTANTIN MASLOV ◽  
LIHONG V. WANG
Keyword(s):  
Reporter Gene ◽  
Photoacoustic Imaging ◽  
Colorimetric Assay ◽  
Response To Therapy ◽  
Dual Wavelength ◽  
Photoacoustic Microscopy ◽  
Simultaneous Imaging ◽  
Feeding Vessels

Photoacoustic molecular imaging, combined with the reporter-gene technique, can provide a valuable tool for cancer research. The expression of the lacZ reporter gene can be imaged using photoacoustic imaging following the injection of X-gal, a colorimetric assay for the lacZ-encoded enzyme β-galactosidase. Dual-wavelength photoacoustic microscopy was used to non-invasively image the detailed morphology of a lacZ-marked 9L gliosarcoma and its surrounding microvasculature simultaneously in vivo, with a superior resolution on the order of 10 μm. Tumor-feeding vessels were found, and the expression level of lacZ in tumor was estimated. With future development of new absorption-enhancing reporter-gene systems, we anticipate this strategy can lead to a better understanding of the role of tumor metabolism in cancer initiation, progression, and metastasis, and in its response to therapy.

scholarly journals The htx and ptx Operons of Pseudomonas stutzeri WM88 Are New Members of the Pho Regulon

2004 ◽  
Vol 186 (17) ◽  
pp. 5876-5882 ◽  
Author(s):  
Andrea K. White ◽  
William W. Metcalf
Keyword(s):  
Reporter Gene ◽  
Pseudomonas Stutzeri ◽  
Deletion Mutants ◽  
Pho Regulon ◽  
Gene Fusions ◽  
New Members ◽  
Starvation Conditions ◽  
P Sources

ABSTRACT The htx and ptx operons of Pseudomonas stutzeri WM88 allow for the use of the inorganic reduced phosphorus (P) compounds hypophosphite (P valence, +1) and phosphite (P valence, +3) as sole P sources. To support the proposed in vivo role for the htx and ptx operons, namely the use of phosphite and hypophosphite as alternative P sources, we used reporter gene fusions to examine their expression levels with respect to various P conditions. Expression of the htx and ptx operons was induced up to 17- and 22-fold, respectively, in cultures grown under phosphate starvation conditions relative to expression in medium with excess phosphate (Pi). However, the presence of the reduced P substrate hypophosphite, phosphite, or methylphosphonate, in addition to excess Pi, did not result in an increase in the expression of either operon. To provide further support for a role of the htx and ptx operons in Pi acquisition, we identified P. stutzeri phoBR homologs and constructed deletion mutants. Induction of the htx and ptx reporter gene fusions in response to growth on limiting Pi was abolished in ΔphoB, ΔphoR, and ΔphoBR mutants, demonstrating that htx and ptx expression is phoBR dependent. The putative LysR-type regulator encoded by ptxE has no apparent role in the expression of the htx and ptx operons, as no effect was observed on the level of induction of either operon in a ΔptxE mutant.

scholarly journals Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy

2006 ◽  
Vol 11 (3) ◽  
pp. 034032 ◽  
Author(s):  
Jung-Taek Oh ◽  
Meng-Lin Li ◽  
Hao F. Zhang ◽  
Konstantin Maslov ◽  
George Stoica ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Dual Wavelength ◽  
Photoacoustic Microscopy ◽  
Skin Melanoma ◽  
Three Dimensional Imaging

scholarly journals Photoacoustic microscopy of tyrosinase reporter gene in vivo

2011 ◽  
Vol 16 (8) ◽  
pp. 080503 ◽  
Author(s):  
Arie Krumholz ◽  
Sarah J. VanVickle-Chavez ◽  
Junjie Yao ◽  
Timothy P. Fleming ◽  
William E. Gillanders ◽  
...  
Keyword(s):  
Reporter Gene ◽  
Photoacoustic Microscopy

Non-invasive and low-artifact in vivo brain imaging by using a scanning acoustic-photoacoustic dual mode microscopy

2022 ◽  
Author(s):  
Wentian Chen ◽  
Chao Tao ◽  
Zizhong Hu ◽  
Songtao Yuan ◽  
Qinghuai Liu ◽  
...  
Keyword(s):  
Brain Imaging ◽  
Photoacoustic Imaging ◽  
Acoustic Microscopy ◽  
Acoustic Properties ◽  
Potential Candidate ◽  
Photoacoustic Microscopy ◽  
Phantom Experiment ◽  
Non Invasive ◽  
Imaging Performance

Abstract Photoacoustic imaging is a potential candidate for in-vivo brain imaging, whereas, its imaging performance could be degraded by inhomogeneous multi-layered media, consisted of scalp and skull. In this work, we propose a low-artifact photoacoustic microscopy (LAPAM) scheme, which combines conventional acoustic-resolution photoacoustic microscopy with scanning acoustic microscopy to suppress the reflection artifacts induced by multi-layers. Based on similar propagation characteristics of photoacoustic signals and ultrasonic echoes, the ultrasonic echoes can be employed as the filters to suppress the reflection artifacts to obtain low-artifact photoacoustic images. Phantom experiment is used to validate the effectiveness of this method. Furthermore, LAPAM is applied for in-vivo imaging mouse brain without removing the scalp and the skull. Experimental results show that the proposed method successfully achieves the low-artifact brain image, which demonstrates the practical applicability of LAPAM. This work might improve the photoacoustic imaging quality in many biomedical applications, which involve tissue with complex acoustic properties, such as brain imaging through scalp and skull.

scholarly journals Dual-Agent Photodynamic Therapy with Optical Clearing Eradicates Pigmented Melanoma in Preclinical Tumor Models

Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1956 ◽  
Author(s):  
Layla Pires ◽  
Valentin Demidov ◽  
Brian C. Wilson ◽  
Ana Gabriela Salvio ◽  
Lilian Moriyama ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Photoacoustic Imaging ◽  
Critical Role ◽  
Tumor Model ◽  
Optical Clearing ◽  
Treatment Regimes ◽  
Pigmented Lesions ◽  
Melanoma Model

Treatment using light-activated photosensitizers (photodynamic therapy, PDT) has shown limited efficacy in pigmented melanoma, mainly due to the poor penetration of light in this tissue. Here, an optical clearing agent (OCA) was applied topically to a cutaneous melanoma model in mice shortly before PDT to increase the effective treatment depth by reducing the light scattering. This was used together with cellular and vascular-PDT, or a combination of both. The effect on tumor growth was measured by longitudinal ultrasound/photoacoustic imaging in vivo and by immunohistology after sacrifice. In a separate dorsal window chamber tumor model, angiographic optical coherence tomography (OCT) generated 3D tissue microvascular images, enabling direct in vivo assessment of treatment response. The optical clearing had minimal therapeutic effect on the in control, non-pigmented cutaneous melanomas but a statistically significant effect (p < 0.05) in pigmented lesions for both single- and dual-photosensitizer treatment regimes. The latter enabled full-depth eradication of tumor tissue, demonstrated by the absence of S100 and Ki67 immunostaining. These studies are the first to demonstrate complete melanoma response to PDT in an immunocompromised model in vivo, with quantitative assessment of tumor volume and thickness, confirmed by (immuno) histological analyses, and with non-pigmented melanomas used as controls to clarify the critical role of melanin in the PDT response. The results indicate the potential of OCA-enhanced PDT for the treatment of pigmented lesions, including melanoma.

The role of the gut microbiota in mood and behaviour. Whether psychobiotics can become an alternative in therapy in psychiatry?

2016 ◽  
Vol 33 (S1) ◽  
pp. S26-S26 ◽  
Author(s):  
S. Van Hemert ◽  
W. Marlicz ◽  
P. Szachta ◽  
E. Pekelharing ◽  
G. Ormel ◽  
...  
Keyword(s):  
Depressive Disorders ◽  
Response To Therapy ◽  
Human Trial ◽  
Pain Anxiety ◽  
Gut Barrier Function ◽  
Psychiatric Disturbances ◽  
Competing Interest

IntroductionNovel research concepts based on therapies aiming to modulate intestinal microbiota are emerging. The evidence is mounting that gut-brain axis plays an important role in the development of mood and depressive disorders [1]. The similarities between blood brain barrier (BBB) and gut vascular barrier (GVB) and their role in chronic diseases have been recently unraveled [2]. Especially convincing data come from animal models, where administration of probiotics and antibiotics in germ and pathogen free mice showed beneficial role in the regulation of behavior, cognition, pain, anxiety and mood.Aims and resultsBased on available data as well as on studies looking at the effect of multispecies probiotics (Ecologic® Barrier containing B.bifidumW23, B.lactisW52, L.acidophilusW37, L.brevisW63, L.caseiW56, L.salivariusW24, L.lactisW19, L.lactisW58) on cognitive reactivity to sad mood in healthy volunteers [3] we designed the human trial aiming to compare microbiome alterations and response to therapy in patients with depression and schizophrenia. Moreover, in vitro and in vivo data support the notion that multispecies probiotics are capable of improving gut barrier function [4] and may alleviate disorders affecting mood and depressive-like behavior. We postulate that therapies modulating the microbiome-gut-brain axis warrant further investigations.ConclusionMultispecies probiotics have the potential to influence the gut-brain axis and alleviate mental disorders. Ongoing clinical study in patients with depression and schizophrenia will help to further unravel the role of gut-brain axis in the treatment of patients with psychiatric disturbances.Disclosure of interestThe authors have not supplied their declaration of competing interest.

POWER OF DUAL-WAVELENGTH APPROACHES IN STUDYING PHYSIOLOGICAL AND FUNCTIONAL CHANGES OF INTACT HEART AND IN VIVO BRAIN

2011 ◽  
Vol 04 (03) ◽  
pp. 261-268 ◽  
Author(s):  
ZHONGCHI LUO ◽  
CONGWU DU
Keyword(s):  
Redox State ◽  
Dual Wavelength ◽  
Oxygen Species ◽  
Ratiometric Fluorescence ◽  
Ischemic Insult ◽  
Perfused Heart ◽  
Functional Changes ◽  
Simultaneous Imaging ◽  
Intact Heart

Since the dual-wavelength spectrophotometer was developed, it has been widely used for studying biological samples and applied to extensive investigations of the electron transport in respiration and redox cofactors, redox state, metabolic control, and the generation of reactive oxygen species in mitochondria. Here, we discuss some extension of dual-wavelength approaches in our research to study the physiological and functional changes in intact hearts and in vivo brain. Specifically, we aimed at (1) making nonratiometric fluorescent indicator become ratiometric fluorescence function for investigation of Ca2+ dynamics in live tissue; (2) eliminating the effects of physiological changes on measurement of intracellular calcium; (3) permitting simultaneous imaging of multiple physiological parameters. The animal models of the perfused heart and transiently ischemic insult of brain are used to validate these approaches for physiological applications.

Procalcific effect of proprotein convertase subtilisin/kexin type 9 (PCSK9) in chronic kidney disease (CKD)

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
N Ferri ◽  
M.G.P Lupo ◽  
M.R Rattazzi
Keyword(s):  
Colorimetric Assay ◽  
Extracellular Calcium ◽  
Calcium Deposition ◽  
Standard Diet ◽  
Plasma Total Cholesterol ◽  
Calcium Crystals ◽  
Positive Effect

Abstract Aim PCSK9 has been recently associated with a higher rate of calcification in hypercholesterolemic, diabetes and CKD patients. The aim of this study was thus to investigate the role of PCSK9 in VC process, under uremic condition, both on in vivo and in vitro experimental settings. Methods Sprauge Dawley rats were fed a standard diet (SD, n=11) or uremic diet (UD, n=11) for 6 weeks. Calcium crystals in aortas were visualized by von Kossa staining and quantified by a colorimetric assay and plasma total cholesterol determined. Control and PCSK9-overexpressing smooth muscle cells (SMCsPCSK9) were cultured with 2.5% FCS ± Pi for 7 days. Hydroxyapatite deposition by SMCs was measured by a colorimetric assay. The number and the content of pro-calcific extracellular vesicles (EVs) budding from the cells were determined. Results The hyperphosphatemia secondary to CKD lead to rat aortic calcification (+7.3-fold) and a significant increase in TC and PCSK9 levels (+1.4 and +2.7-fold, respectively). Higher expression of PCSK9 was also observed in kidney (+4.8-fold) and liver (+1.5-fold). SMCsPCSK9 showed higher extracellular calcium deposition (+1.4-fold) in response to Pi and increase EVs production (+7-fold). The incubation of control cells with recombinant PCSK9 did not induce extracellular calcium deposition. Conclusions Our study suggest a positive effect of intracellular PCSK9 on vascular calcification in CKD condition. Pro-calcific budding of EVs seems one of the possible mediators of this process. PCSK9 and calcification Funding Acknowledgement Type of funding source: None

scholarly journals Sensitive quantification of carbon monoxide in vivo reveals a protective role of circulating hemoglobin in CO intoxication

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Qiyue Mao ◽  
Akira T. Kawaguchi ◽  
Shun Mizobata ◽  
Roberto Motterlini ◽  
Roberta Foresti ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Colorimetric Assay ◽  
Protective Role ◽  
Supramolecular Compound ◽  
Cyclodextrin Dimer ◽  
Gaseous Molecule ◽  
Co Intoxication ◽  
The Brain

AbstractCarbon monoxide (CO) is a gaseous molecule known as the silent killer. It is widely believed that an increase in blood carboxyhemoglobin (CO-Hb) is the best biomarker to define CO intoxication, while the fact that CO accumulation in tissues is the most likely direct cause of mortality is less investigated. There is no reliable method other than gas chromatography to accurately determine CO content in tissues. Here we report the properties and usage of hemoCD1, a synthetic supramolecular compound composed of an iron(II)porphyrin and a cyclodextrin dimer, as an accessible reagent for a simple colorimetric assay to quantify CO in biological samples. The assay was validated in various organ tissues collected from rats under normal conditions and after exposure to CO. The kinetic profile of CO in blood and tissues after CO treatment suggested that CO accumulation in tissues is prevented by circulating Hb, revealing a protective role of Hb in CO intoxication. Furthermore, hemoCD1 was used in vivo as a CO removal agent, showing that it acts as an effective adjuvant to O2 ventilation to eliminate residual CO accumulated in organs, including the brain. These findings open new therapeutic perspectives to counteract the toxicity associated with CO poisoning.

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