1
|
Liu S, Liu F, Lin Z, Yin W, Fang S, Piao Y, Liu L, Shen Y. Identification of cortical arteries and veins in awake mice using two-photon microscopy. J Anat 2024. [PMID: 39034848 DOI: 10.1111/joa.14110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 06/03/2024] [Accepted: 06/28/2024] [Indexed: 07/23/2024] Open
Abstract
Distinguishing arteries from veins in the cerebral cortex is critical for studying hemodynamics under pathophysiological conditions, which plays an important role in the diagnosis and treatment of various vessel-related diseases. However, due to the complexity of the cerebral vascular network, it is challenging to identify arteries and veins in vivo. Here, we demonstrate an artery-vein separation method that employs a combination of multiple scanning modes of two-photon microscopy and a custom-designed stereoscopic fixation device for mice. In this process, we propose a novel method for determining the line scanning direction, which allows us to determine the blood flow directions. The vasculature branches have been identified using an optimized z-stack scanning mode, followed by the separation of blood vessel types according to the directions of blood flow and branching patterns. Using this strategy, the penetrating arterioles and penetrating venules in awake mice could be accurately identified and the type of cerebral thrombus has been also successfully isolated without any empirical knowledge or algorithms. Our research presents a new, more accurate, and efficient method for cortical artery-vein separation in awake mice, providing a useful strategy for the application of two-photon microscopy in the study of cerebrovascular pathophysiology.
Collapse
Affiliation(s)
- Shuangshuang Liu
- Core Facilities, Zhejiang University School of Medicine, Hangzhou, China
| | - FangYue Liu
- School of Brain Science and Brain Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhaoxiaonan Lin
- Core Facilities, Zhejiang University School of Medicine, Hangzhou, China
| | - Wei Yin
- Core Facilities, Zhejiang University School of Medicine, Hangzhou, China
| | - Sanhua Fang
- Core Facilities, Zhejiang University School of Medicine, Hangzhou, China
| | - Ying Piao
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China
| | - Li Liu
- Core Facilities, Zhejiang University School of Medicine, Hangzhou, China
| | - Yi Shen
- School of Brain Science and Brain Medicine, Zhejiang University School of Medicine, Hangzhou, China
- NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University, Hangzhou, China
- National Health and Disease Human Brain Tissue Resource Center, Hangzhou, China
| |
Collapse
|
2
|
Roussakis E, Cascales JP, Yoeli D, Cralley A, Goss A, Wiatrowski A, Carvalho M, Moore HB, Moore EE, Huang CA, Evans CL. Versatile, in-line optical oxygen tension sensors for continuous monitoring during ex vivo kidney perfusion. SENSORS & DIAGNOSTICS 2024; 3:1014-1019. [PMID: 38882471 PMCID: PMC11170683 DOI: 10.1039/d3sd00240c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 02/19/2024] [Indexed: 06/18/2024]
Abstract
Integration of physiological sensing modalities within tissue and organ perfusion systems is becoming a steadily expanding field of research, aimed at achieving technological breakthrough innovations that will expand the sites and clinical settings at which such systems can be used. This is becoming possible in part due to the advancement of user-friendly optical sensors in recent years, which rely both on synthetic, luminescent sensor molecules and inexpensive, low-power electronic components for device engineering. In this article we report a novel approach towards enabling automated, continuous monitoring of oxygenation during ex vivo organ perfusion, by combining versatile flow cell components and low-power, programmable electronic readout devices. The sensing element comprises a 3D printed, miniature flow cell with tubing connectors and an affixed oxygen-sensing thin film material containing in-house developed, brightly-emitting metalloporphyrin phosphor molecules embedded within a polymer matrix. Proof-of-concept validation of this technology is demonstrated through integration within the tubing circuit of a transportable medical device for hypothermic oxygenated machine perfusion of extracted kidneys as a model for organs to be preserved as transplants.
Collapse
Affiliation(s)
- Emmanuel Roussakis
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
| | - Juan Pedro Cascales
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
| | - Dor Yoeli
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus Aurora Colorado USA
| | - Alexis Cralley
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus Aurora Colorado USA
| | - Avery Goss
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
| | - Anna Wiatrowski
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
| | - Maia Carvalho
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
| | - Hunter B Moore
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus Aurora Colorado USA
| | - Ernest E Moore
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus Aurora Colorado USA
| | - Christene A Huang
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus Aurora Colorado USA
| | - Conor L Evans
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School Charlestown Massachusetts USA
| |
Collapse
|
3
|
Zhang Y, Qi X, Li W, Wan M, Ning X, Hu J. Research on the classification of early-stage brain edema by combining intrinsic optical signal imaging and laser speckle contrast imaging. JOURNAL OF BIOPHOTONICS 2024; 17:e202300394. [PMID: 38169143 DOI: 10.1002/jbio.202300394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/24/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024]
Abstract
The early detection and pathological classification of brain edema are very important for symptomatic treatment. The dual-optical imaging system (DOIS) consists of intrinsic optical signal imaging (IOSI) and laser speckle contrast imaging (LSCI), which can acquire cerebral hemodynamic parameters of mice in real-time, including changes of oxygenated hemoglobin concentration ( Δ C HbO 2 ), deoxyhemoglobin concentration (ΔCHbR) and relative cerebral blood flow (rCBF) within the field of view. The slope sum of Δ C HbO 2 , ΔCHbR and rCBF was proposed to classify vasogenic edema (VE) and cytotoxic edema (CE). The slope sum values in the VE and CE group remain statistically different and the classification results provide higher accuracy of more than 93% for early brain edema detection. In conclusion, the differences of hemodynamic parameters between VE and CE in the early stage were revealed and the method helps in the classification of early brain edema.
Collapse
Affiliation(s)
- Yameng Zhang
- Nanjing University of Aeronautics and Astronautics, Nanjing, China
- Nanjing Institute of Technology, Nanjing, China
| | - Xinping Qi
- Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Weitao Li
- Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Min Wan
- Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Xue Ning
- Nanjing University of Aeronautics and Astronautics, Nanjing, China
| | - Jin Hu
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| |
Collapse
|
4
|
Smith C, Santorelli A, Engelmann S, Dunn AK. All fiber-based illumination system for multi-exposure speckle imaging. BIOMEDICAL OPTICS EXPRESS 2023; 14:771-782. [PMID: 36874493 PMCID: PMC9979660 DOI: 10.1364/boe.476178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/15/2022] [Accepted: 12/29/2022] [Indexed: 06/18/2023]
Abstract
Monitoring blood flow is critical to treatment efficacy in many surgical settings. Laser speckle contrast imaging (LSCI) is a simple, real-time, label-free optical technique for monitoring blood flow that has emerged as a promising technique but lacks the ability to make repeatable quantitative measurements. Multi-exposure speckle imaging (MESI) is an extension of LSCI that requires increased complexity of instrumentation, which has limited its adoption. In this paper, we design and fabricate a compact, fiber-coupled MESI illumination system (FCMESI) that is substantially smaller and less complex than previous systems. Using microfluidics flow phantoms, we demonstrate that the FCMESI system measures flow with an accuracy and repeatability equivalent to traditional free space MESI illumination systems. With an in vivo stroke model, we also demonstrate the ability of FCMESI to monitor cerebral blood flow changes.
Collapse
|
5
|
Chong SH, Ong YH, El Khatib M, Allu SR, Parthasarathy AB, Greenberg JH, Yodh AG, Vinogradov SA. Real-time tracking of brain oxygen gradients and blood flow during functional activation. NEUROPHOTONICS 2022; 9:045006. [PMID: 36457848 PMCID: PMC9704417 DOI: 10.1117/1.nph.9.4.045006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 11/01/2022] [Indexed: 06/11/2023]
Abstract
Significance Cerebral metabolic rate of oxygen ( CMRO 2 ) consumption is a key physiological variable that characterizes brain metabolism in a steady state and during functional activation. Aim We aim to develop a minimally invasive optical technique for real-time measurement of CMRO 2 concurrently with cerebral blood flow (CBF). Approach We used a pair of macromolecular phosphorescent probes with nonoverlapping optical spectra, which were localized in the intra- and extravascular compartments of the brain tissue, thus providing a readout of oxygen gradients between these two compartments. In parallel, we measured CBF using laser speckle contrast imaging. Results The method enables computation and tracking of CMRO 2 during functional activation with high temporal resolution ( ∼ 7 Hz ). In contrast to other approaches, our assessment of CMRO 2 does not require measurements of CBF or hemoglobin oxygen saturation. Conclusions The independent records of intravascular and extravascular partial pressures of oxygen, CBF, and CMRO 2 provide information about the physiological events that accompany neuronal activation, creating opportunities for dynamic quantification of brain metabolism.
Collapse
Affiliation(s)
- Sang Hoon Chong
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Yi Hong Ong
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, Department of Radiation Oncology, Philadelphia, Pennsylvania, United States
| | - Mirna El Khatib
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| | - Srinivasa Rao Allu
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| | - Ashwin B. Parthasarathy
- University of South Florida, Department of Electrical Engineering, Tampa, Florida, United States
| | - Joel H. Greenberg
- University of Pennsylvania, Department of Neurology, Philadelphia, Pennsylvania, United States
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania, United States
| | - Sergei A. Vinogradov
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts and Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
| |
Collapse
|
6
|
Seong D, Yi S, Han S, Lee J, Park S, Hwang YH, Kim J, Kim HK, Jeon M. Target ischemic stroke model creation method using photoacoustic microscopy with simultaneous vessel monitoring and dynamic photothrombosis induction. PHOTOACOUSTICS 2022; 27:100376. [PMID: 35734368 PMCID: PMC9207728 DOI: 10.1016/j.pacs.2022.100376] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 06/02/2022] [Indexed: 06/02/2023]
Abstract
The ischemic stroke animal model evaluates the efficacy of reperfusion and neuroprotective strategies for ischemic injuries. Various conventional methods have been reported to induce the ischemic models; however, controlling specific neurological deficits, mortality rates, and the extent of the infarction is difficult as the size of the affected region is not precisely controlled. In this paper, we report a single laser-based localized target ischemic stroke model development method by simultaneous vessel monitoring and photothrombosis induction using photoacoustic microscopy (PAM), which has minimized the infarct size at precise location with high reproducibility. The proposed method has significantly reduced the infarcted region by illuminating the precise localization. The reproducibility and validity of suggested method have been demonstrated through repeated experiments and histological analyses. These results demonstrate that our method can provide the ischemic stroke model closest to the clinical pathology for brain ischemia research from inducement, occurrence mechanisms to the recovery process.
Collapse
Affiliation(s)
- Daewoon Seong
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, Daegu 41566, the Republic of Korea
| | - Soojin Yi
- Bio-Medical Institute, Kyungpook National University Hospital, Daegu 41404, the Republic of Korea
- Department of Ophthalmology, School of Medicine, Kyungpook National University, Daegu 41944, the Republic of Korea
- Department of Biomedical Science, The Graduate School, Kyungpook National University, Daegu 41944, the Republic of Korea
| | - Sangyeob Han
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, Daegu 41566, the Republic of Korea
- Institute of Biomedical Engineering, School of Medicine, Kyungpook National University, Daegu 41566, the Republic of Korea
| | - Jaeyul Lee
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, Daegu 41566, the Republic of Korea
- Department of Bioengineering, University of California, Los Angeles, CA 90095, USA
| | - Sungjo Park
- Pohang Innotown Center, Pohang University of Science and Technology, Pohang 37673, the Republic of Korea
| | - Yang-Ha Hwang
- Department of Neurology, School of Medicine, Kyungpook National University, Daegu 41944, the Republic of Korea
| | - Jeehyun Kim
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, Daegu 41566, the Republic of Korea
| | - Hong Kyun Kim
- Bio-Medical Institute, Kyungpook National University Hospital, Daegu 41404, the Republic of Korea
- Department of Ophthalmology, School of Medicine, Kyungpook National University, Daegu 41944, the Republic of Korea
- Department of Biomedical Science, The Graduate School, Kyungpook National University, Daegu 41944, the Republic of Korea
| | - Mansik Jeon
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, Daegu 41566, the Republic of Korea
| |
Collapse
|
7
|
Hu Z, Li D, Zhong X, Li Y, Xuan A, Yu T, Zhu J, Zhu D. In vivo tissue optical clearing assisted through-skull targeted photothrombotic ischemic stroke model in mice. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:065001. [PMID: 35676747 PMCID: PMC9174889 DOI: 10.1117/1.jbo.27.6.065001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
SIGNIFICANCE Photothrombotic stroke is an important and widely used model for ischemic stroke research. However, the significant scattering of the skull during the procedure limits the light's ability to penetrate and focus on its target. Targeted photothrombosis uses surgery-based skull windows to obtain optical access to the brain, but it renders the brain's environment unnatural even before a stroke is established. AIM To establish a targeted, controllable ischemic stroke model in mice through an intact skull. APPROACH The in vivo skull optical clearing technique provides a craniotomy-free "optical window" that allows light to penetrate. Alongside the local photodynamic effect, we have established targeted photothrombosis without skull removal, effectively controlling the degree of thrombotic occlusion by changing the light dose. RESULTS Ex vivo and in vivo results demonstrated that skull optical clearing treatment significantly enhanced light's ability to penetrate the skull and focus on its target, contributing to thrombotic occlusion. The skull optical clearing window was also used for continuous blood flow mapping, and the relationship between light dose and injury degree was evaluated over 14 days of monitoring. Per our findings, increasing the light dose was accompanied by more severe infarction, indicating that the model was easily controllable. CONCLUSIONS Herein, a targeted, controllable ischemic stroke model was established by combinedly running an in vivo skull optical clearing technique and a photothrombotic procedure, avoiding unnecessary damage or environmental changes to the brain caused by surgery on the skull. Our established model should offer significant value to research on ischemic stroke.
Collapse
Affiliation(s)
- Zhengwu Hu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Dongyu Li
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Xiang Zhong
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Yusha Li
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Ang Xuan
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Tingting Yu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Jingtan Zhu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| | - Dan Zhu
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Hubei, Wuhan, China
- Huazhong University of Science and Technology, MoE Key Laboratory for Biomedical Photonics, Hubei, Wuhan, China
- Optics Valley Laboratory, Hubei, China
| |
Collapse
|
8
|
Zeng C, Chen Z, Yang H, Fan Y, Fei L, Chen X, Zhang M. Advanced high resolution three-dimensional imaging to visualize the cerebral neurovascular network in stroke. Int J Biol Sci 2022; 18:552-571. [PMID: 35002509 PMCID: PMC8741851 DOI: 10.7150/ijbs.64373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/28/2021] [Indexed: 11/05/2022] Open
Abstract
As an important method to accurately and timely diagnose stroke and study physiological characteristics and pathological mechanism in it, imaging technology has gone through more than a century of iteration. The interaction of cells densely packed in the brain is three-dimensional (3D), but the flat images brought by traditional visualization methods show only a few cells and ignore connections outside the slices. The increased resolution allows for a more microscopic and underlying view. Today's intuitive 3D imagings of micron or even nanometer scale are showing its essentiality in stroke. In recent years, 3D imaging technology has gained rapid development. With the overhaul of imaging mediums and the innovation of imaging mode, the resolution has been significantly improved, endowing researchers with the capability of holistic observation of a large volume, real-time monitoring of tiny voxels, and quantitative measurement of spatial parameters. In this review, we will summarize the current methods of high-resolution 3D imaging applied in stroke.
Collapse
Affiliation(s)
- Chudai Zeng
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Zhuohui Chen
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Haojun Yang
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Yishu Fan
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Lujing Fei
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Xinghang Chen
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Mengqi Zhang
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| |
Collapse
|
9
|
Mirg S, Chen H, Turner KL, Gheres KW, Liu J, Gluckman BJ, Drew PJ, Kothapalli SR. Awake mouse brain photoacoustic and optical imaging through a transparent ultrasound cranial window. OPTICS LETTERS 2022; 47:1121-1124. [PMID: 35230306 DOI: 10.1364/ol.450648] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Optical resolution photoacoustic microscopy (OR-PAM) can map the cerebral vasculature at capillary-level resolution. However, the OR-PAM setup's bulky imaging head makes awake mouse brain imaging challenging and inhibits its integration with other optical neuroimaging modalities. Moreover, the glass cranial windows used for optical microscopy are unsuitable for OR-PAM due to the acoustic impedance mismatch between the glass plate and the tissue. To overcome these challenges, we propose a lithium niobate based transparent ultrasound transducer (TUT) as a cranial window on a thinned mouse skull. The TUT cranial window simplifies the imaging head considerably due to its dual functionality as an optical window and ultrasound transducer. The window remains stable for six weeks, with no noticeable inflammation and minimal bone regrowth. The TUT window's potential is demonstrated by imaging the awake mouse cerebral vasculature using OR-PAM, intrinsic optical signal imaging, and two-photon microscopy. The TUT cranial window can potentially also be used for ultrasound stimulation and simultaneous multimodal imaging of the awake mouse brain.
Collapse
|
10
|
Sullender CT, Richards LM, He F, Luan L, Dunn AK. Dynamics of isoflurane-induced vasodilation and blood flow of cerebral vasculature revealed by multi-exposure speckle imaging. J Neurosci Methods 2022; 366:109434. [PMID: 34863840 PMCID: PMC9258779 DOI: 10.1016/j.jneumeth.2021.109434] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/12/2021] [Accepted: 11/29/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND Anesthetized animal models are used extensively during neurophysiological and behavioral studies despite systemic effects from anesthesia that undermine both accurate interpretation and translation to awake human physiology. The majority of work examining the impact of anesthesia on cerebral blood flow (CBF) has been restricted to before and after measurements with limited spatial resolution. NEW METHOD We used multi-exposure speckle imaging (MESI), an advanced form of laser speckle contrast imaging (LSCI), to characterize the dynamics of isoflurane anesthesia induction on cerebral vasculature and blood flow in the mouse brain. RESULTS The large anatomical changes caused by isoflurane are depicted with wide-field imagery and video highlighting the induction of general anesthesia. Within minutes of exposure, both vessel diameter and blood flow increased drastically compared to the awake state and remained elevated for the duration of imaging. An examination of the dynamics of anesthesia induction reveals that blood flow increased faster in arteries than in veins or parenchyma regions. COMPARISON WITH EXISTING METHODS MESI offers robust hemodynamic measurements across large fields-of-view and high temporal resolutions sufficient for continuous visualization of cerebrovascular events featuring major changes in blood flow. CONCLUSION The large alterations caused by isoflurane anesthesia to the cortical vasculature and CBF are readily characterized using MESI. These changes are unrepresentative of normal physiology and provide further evidence that neuroscience experiments would benefit from transitioning to un-anesthetized awake animal models.
Collapse
Affiliation(s)
- Colin T Sullender
- Department of Biomedical Engineering, University of Texas at Austin, 107 W. Dean Keeton Street Stop C0800, Austin, TX 78712, United States
| | - Lisa M Richards
- Department of Biomedical Engineering, University of Texas at Austin, 107 W. Dean Keeton Street Stop C0800, Austin, TX 78712, United States
| | - Fei He
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, United States
| | - Lan Luan
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, United States; Department of Bioengineering, Rice University, 6100 Main Street, Houston, TX 77005, United States
| | - Andrew K Dunn
- Department of Biomedical Engineering, University of Texas at Austin, 107 W. Dean Keeton Street Stop C0800, Austin, TX 78712, United States.
| |
Collapse
|
11
|
Chelushkin PS, Shakirova JR, Kritchenkov IS, Baigildin VA, Tunik SP. Phosphorescent NIR emitters for biomedicine: applications, advances and challenges. Dalton Trans 2021; 51:1257-1280. [PMID: 34878463 DOI: 10.1039/d1dt03077a] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Application of NIR (near-infrared) emitting transition metal complexes in biomedicine is a rapidly developing area of research. Emission of this class of compounds in the "optical transparency windows" of biological tissues and the intrinsic sensitivity of their phosphorescence to oxygen resulted in the preparation of several commercial oxygen sensors capable of deep (up to whole-body) and quantitative mapping of oxygen gradients suitable for in vivo experimental studies. In addition to this achievement, the last decade has also witnessed the increased growth of successful alternative applications of NIR phosphors that include (i) site-specific in vitro and in vivo visualization of sophisticated biological models ranging from 3D cell cultures to intact animals; (ii) sensing of various biologically relevant analytes, such as pH, reactive oxygen and nitrogen species, RedOx agents, etc.; (iii) and several therapeutic applications such as photodynamic (PDT), photothermal (PTT), and photoactivated cancer (PACT) therapies as well as their combinations with other therapeutic and imaging modalities to yield new variants of combined therapies and theranostics. Nevertheless, emerging applications of these compounds in experimental biomedicine and their implementation as therapeutic agents practically applicable in PDT, PTT, and PACT face challenges related to a critically important improvement of their photophysical and physico-chemical characteristics. This review outlines the current state of the art and achievements of the last decade and stresses the most promising trends, major development prospects, and challenges in the design of NIR phosphors suitable for biomedical applications.
Collapse
Affiliation(s)
- Pavel S Chelushkin
- Institute of Chemistry, St. Petersburg State University, Universitetskii pr., 26, 198504, St. Petersburg, Russia.
| | - Julia R Shakirova
- Institute of Chemistry, St. Petersburg State University, Universitetskii pr., 26, 198504, St. Petersburg, Russia.
| | - Ilya S Kritchenkov
- Institute of Chemistry, St. Petersburg State University, Universitetskii pr., 26, 198504, St. Petersburg, Russia.
| | - Vadim A Baigildin
- Institute of Chemistry, St. Petersburg State University, Universitetskii pr., 26, 198504, St. Petersburg, Russia.
| | - Sergey P Tunik
- Institute of Chemistry, St. Petersburg State University, Universitetskii pr., 26, 198504, St. Petersburg, Russia.
| |
Collapse
|
12
|
Longitudinal functional imaging of VIP interneurons reveals sup-population specific effects of stroke that are rescued with chemogenetic therapy. Nat Commun 2021; 12:6112. [PMID: 34671051 PMCID: PMC8528851 DOI: 10.1038/s41467-021-26405-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 10/04/2021] [Indexed: 01/20/2023] Open
Abstract
Stroke profoundly disrupts cortical excitability which impedes recovery, but how it affects the function of specific inhibitory interneurons, or subpopulations therein, is poorly understood. Interneurons expressing vasoactive intestinal peptide (VIP) represent an intriguing stroke target because they can regulate cortical excitability through disinhibition. Here we chemogenetically augmented VIP interneuron excitability in a murine model of photothrombotic stroke and show that it enhances somatosensory responses and improves recovery of paw function. Using longitudinal calcium imaging, we discovered that stroke primarily disrupts the fidelity (fraction of responsive trials) and predictability of sensory responses within a subset of highly active VIP neurons. Partial recovery of responses occurred largely within these active neurons and was not accompanied by the recruitment of minimally active neurons. Importantly, chemogenetic stimulation preserved sensory response fidelity and predictability in highly active neurons. These findings provide a new depth of understanding into how stroke and prospective therapies (chemogenetics), can influence subpopulations of inhibitory interneurons.
Collapse
|
13
|
Jafari CZ, Sullender CT, Miller DR, Mihelic SA, Dunn AK. Effect of vascular structure on laser speckle contrast imaging. BIOMEDICAL OPTICS EXPRESS 2020; 11:5826-5841. [PMID: 33149989 PMCID: PMC7587253 DOI: 10.1364/boe.401235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/31/2020] [Accepted: 09/08/2020] [Indexed: 06/11/2023]
Abstract
Laser speckle contrast imaging (LSCI) is a powerful tool for non-invasive, real-time imaging of blood flow in tissue. However, the effect of tissue geometry on the form of the electric field autocorrelation function and speckle contrast values is yet to be investigated. In this paper, we present an ultrafast forward model for simulating a speckle contrast image with the ability to rapidly update the image for a desired illumination pattern and flow perturbation. We demonstrate the first simulated speckle contrast image and compare it against experimental results. We simulate three mouse-specific cerebral cortex decorrelation time images and implement three different schemes for analyzing the effects of homogenization of vascular structure on correlation decay times. Our results indicate that dissolving structure and assuming homogeneous geometry creates up to ∼ 10x shift in the correlation function decay times and alters its form compared with the case for which the exact geometry is simulated. These effects are more pronounced for point illumination and detection imaging schemes, highlighting the significance of accurate modeling of the three-dimensional vascular geometry for accurate blood flow estimates.
Collapse
Affiliation(s)
- Chakameh Z. Jafari
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Colin T. Sullender
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA
| | - David R. Miller
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Samuel A. Mihelic
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Andrew K. Dunn
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA
| |
Collapse
|
14
|
Cao X, Allu SR, Jiang S, Gunn Bs JR, Yao PhD C, Xin PhD J, Bruza PhD P, Gladstone ScD DJ, Jarvis Md PhD LA, Tian PhD J, Swartz Md Msph PhD HM, Vinogradov PhD SA, Pogue PhD BW. High-Resolution pO 2 Imaging Improves Quantification of the Hypoxic Fraction in Tumors During Radiation Therapy. Int J Radiat Oncol Biol Phys 2020; 109:603-613. [PMID: 33002542 DOI: 10.1016/j.ijrobp.2020.09.046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/14/2020] [Accepted: 09/21/2020] [Indexed: 12/22/2022]
Abstract
PURPOSE The extreme microscopic heterogeneity of tumors makes it difficult to characterize tumor hypoxia. We evaluated how changes in the spatial resolution of oxygen imaging could alter measures of tumor hypoxia and their correlation to radiation therapy response. METHODS AND MATERIALS Cherenkov-Excited Luminescence Imaging in combination with an oxygen probe, Oxyphor PtG4 was used to directly image tumor pO2 distributions with 0.2 mm spatial resolution at the time of radiation delivery. These pO2 images were analyzed with variations of reduced spatial resolution from 0.2 mm to 5 mm, to investigate the influence of how reduced imaging spatial resolution would affect the observed tumor hypoxia. As an in vivo validation test, mice bearing tumor xenografts were imaged for hypoxic fraction and median pO2 to examine the predictive link with tumor response to radiation therapy, while accounting for spatial resolution. RESULTS In transitioning from voxel sizes of 200 μm to 3 mm, the median pO2 values increased by a few mm Hg, and the hypoxic fraction decreased by more than 50%. When looking at radiation-responsive tumors, the median pO2 values changed just a few mm Hg as a result of treatment, and the hypoxic fractions changed by as much as 50%. This latter change, however, could only be seen when sampling was performed with high spatial resolution. Median pO2 or similar quantities obtained from low resolution measurements are commonly used in clinical practice, however these parameters are much less sensitive to changes in the tumor microenvironment than the tumor hypoxic fraction obtained from high-resolution oxygen images. CONCLUSIONS This study supports the hypothesis that for adequate measurements of the tumor response to radiation therapy, oxygen imaging with high spatial resolution is required to accurately characterize the hypoxic fraction.
Collapse
Affiliation(s)
- Xu Cao
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire; Xidian University, Engineering Research Center of Molecular & Neuroimaging, Ministry of Education, School of Life Science and Technology, Xi'an, Shaanxi, China
| | - Srinivasa Rao Allu
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Chemistry, School or Arts and Sciences, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Shudong Jiang
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire
| | - Jason R Gunn Bs
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire
| | - Cuiping Yao PhD
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire; Xi'an Jiaotong University, Institute of Biomedical Analytical Technology and Instrumentation, School of Life Science and Technology, Key Laboratory of Biomedical Information Engineering of Ministry of Education, Xi'an, Shaanxi, China
| | - Jing Xin PhD
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire; Xi'an Jiaotong University, Institute of Biomedical Analytical Technology and Instrumentation, School of Life Science and Technology, Key Laboratory of Biomedical Information Engineering of Ministry of Education, Xi'an, Shaanxi, China
| | - Petr Bruza PhD
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire
| | - David J Gladstone ScD
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire; Department of Medicine, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire
| | - Lesley A Jarvis Md PhD
- Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire; Department of Medicine, Geisel School of Medicine, Dartmouth College, Hanover, New Hampshire
| | - Jie Tian PhD
- Xidian University, Engineering Research Center of Molecular & Neuroimaging, Ministry of Education, School of Life Science and Technology, Xi'an, Shaanxi, China; CAS Key Laboratory of Molecular Imaging, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | | | - Sergei A Vinogradov PhD
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Chemistry, School or Arts and Sciences, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Brian W Pogue PhD
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire; Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire.
| |
Collapse
|
15
|
He F, Lycke R, Ganji M, Xie C, Luan L. Ultraflexible Neural Electrodes for Long-Lasting Intracortical Recording. iScience 2020; 23:101387. [PMID: 32745989 PMCID: PMC7398974 DOI: 10.1016/j.isci.2020.101387] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 06/22/2020] [Accepted: 07/16/2020] [Indexed: 11/16/2022] Open
Abstract
Implanted electrodes provide one of the most important neurotechniques for fundamental and translational neurosciences by permitting time-resolved electrical detection of individual neurons in vivo. However, conventional rigid electrodes typically cannot provide stable, long-lasting recordings. Numerous interwoven biotic and abiotic factors at the tissue-electrode interface lead to short- and long-term instability of the recording performance. Making neural electrodes flexible provides a promising approach to mitigate these challenges on the implants and at the tissue-electrode interface. Here we review the recent progress of ultraflexible neural electrodes and discuss the engineering principles, the material properties, and the implantation strategies to achieve stable tissue-electrode interface and reliable unit recordings in living brains.
Collapse
Affiliation(s)
- Fei He
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA; NeuroEngineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA
| | - Roy Lycke
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA; NeuroEngineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA; Department of Biomedical Engineering, University of Texas at Austin, 107 Dean Keeton, Austin, TX 78712, USA
| | - Mehran Ganji
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA; NeuroEngineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA; Department of Biomedical Engineering, University of Texas at Austin, 107 Dean Keeton, Austin, TX 78712, USA
| | - Chong Xie
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA; NeuroEngineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA; Department of Bioengineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
| | - Lan Luan
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA; NeuroEngineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA; Department of Bioengineering, Rice University, 6100 Main Street, Houston, TX 77005, USA.
| |
Collapse
|
16
|
He F, Sullender CT, Zhu H, Williamson MR, Li X, Zhao Z, Jones TA, Xie C, Dunn AK, Luan L. Multimodal mapping of neural activity and cerebral blood flow reveals long-lasting neurovascular dissociations after small-scale strokes. SCIENCE ADVANCES 2020; 6:eaba1933. [PMID: 32494746 PMCID: PMC7244270 DOI: 10.1126/sciadv.aba1933] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 03/10/2020] [Indexed: 06/02/2023]
Abstract
Neurovascular coupling, the close spatial and temporal relationship between neural activity and hemodynamics, is disrupted in pathological brain states. To understand the altered neurovascular relationship in brain disorders, longitudinal, simultaneous mapping of neural activity and hemodynamics is critical yet challenging to achieve. Here, we use a multimodal neural platform in a mouse model of stroke and realize long-term, spatially resolved tracking of intracortical neural activity and cerebral blood flow in the same brain regions. We observe a pronounced neurovascular dissociation that occurs immediately after small-scale strokes, becomes the most severe a few days after, lasts into chronic periods, and varies with the level of ischemia. Neuronal deficits extend spatiotemporally, whereas restoration of cerebral blood flow occurs sooner and reaches a higher relative value. Our findings reveal the neurovascular impact of ministrokes and inform the limitation of neuroimaging techniques that infer neural activity from hemodynamic responses.
Collapse
Affiliation(s)
- Fei He
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
- Neuroengineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA
| | - Colin T. Sullender
- Department of Biomedical Engineering, The University of Texas at Austin, 107 E. Dean Keeton Street, 1 University Station, C0800, Austin, TX 78712, USA
| | - Hanlin Zhu
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
| | - Michael R. Williamson
- Institute for Neuroscience, The University of Texas at Austin, 1 University Station, Stop C7000, Austin, TX 78712, USA
| | - Xue Li
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
| | - Zhengtuo Zhao
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
- Neuroengineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA
| | - Theresa A. Jones
- Department of Psychology, The University of Texas at Austin, 108 E. Dean Keeton Street, Stop A8000, SEA 6.106, Austin, TX 78712, USA
| | - Chong Xie
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
- Neuroengineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
| | - Andrew K. Dunn
- Department of Biomedical Engineering, The University of Texas at Austin, 107 E. Dean Keeton Street, 1 University Station, C0800, Austin, TX 78712, USA
| | - Lan Luan
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
- Neuroengineering Initiative, Rice University, 6500 Main Street, Houston, TX 77005, USA
- Department of Bioengineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
| |
Collapse
|
17
|
Sunil S, Erdener SE, Lee BS, Postnov D, Tang J, Kura S, Cheng X, Chen IA, Boas DA, Kılıç K. Awake chronic mouse model of targeted pial vessel occlusion via photothrombosis. NEUROPHOTONICS 2020; 7:015005. [PMID: 32042854 PMCID: PMC6992450 DOI: 10.1117/1.nph.7.1.015005] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 01/02/2020] [Indexed: 05/09/2023]
Abstract
Animal models of stroke are used extensively to study the mechanisms involved in the acute and chronic phases of recovery following stroke. A translatable animal model that closely mimics the mechanisms of a human stroke is essential in understanding recovery processes as well as developing therapies that improve functional outcomes. We describe a photothrombosis stroke model that is capable of targeting a single distal pial branch of the middle cerebral artery with minimal damage to the surrounding parenchyma in awake head-fixed mice. Mice are implanted with chronic cranial windows above one hemisphere of the brain that allow optical access to study recovery mechanisms for over a month following occlusion. Additionally, we study the effect of laser spot size used for occlusion and demonstrate that a spot size with small axial and lateral resolution has the advantage of minimizing unwanted photodamage while still monitoring macroscopic changes to cerebral blood flow during photothrombosis. We show that temporally guiding illumination using real-time feedback of blood flow dynamics also minimized unwanted photodamage to the vascular network. Finally, through quantifiable behavior deficits and chronic imaging we show that this model can be used to study recovery mechanisms or the effects of therapeutics longitudinally.
Collapse
Affiliation(s)
- Smrithi Sunil
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Address all correspondence to Smrithi Sunil, E-mail:
| | - Sefik Evren Erdener
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Hacettepe University, Institute of Neurological Sciences and Psychiatry, Ankara, Turkey
| | - Blaire S. Lee
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Dmitry Postnov
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
- Copenhagen University, Department of Biomedical Sciences, Copenhagen, Denmark
| | - Jianbo Tang
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Sreekanth Kura
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Xiaojun Cheng
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Ichun Anderson Chen
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - David A. Boas
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| | - Kıvılcım Kılıç
- Boston University, Neurophotonics Center, Department of Biomedical Engineering, Boston, Massachusetts, United States
| |
Collapse
|
18
|
Torres Filho IP, Barraza D, Hildreth K, Williams C, Dubick MA. Cremaster muscle perfusion, oxygenation, and heterogeneity revealed by a new automated acquisition system in a rodent model of prolonged hemorrhagic shock. J Appl Physiol (1985) 2019; 127:1548-1561. [PMID: 31670599 DOI: 10.1152/japplphysiol.00570.2019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Local blood flow/oxygen partial pressure (Po2) distributions and flow-Po2 relationships are physiologically relevant. They affect the pathophysiology and treatment of conditions like hemorrhagic shock (HS), but direct noninvasive measures of flow, Po2, and their heterogeneity during prolonged HS are infrequently presented. To fill this void, we report the first quantitative evaluation of flow-Po2 relationships and heterogeneities in normovolemia and during several hours of HS using noninvasive, unbiased, automated acquisition. Anesthetized rats were subjected to tracheostomy, arterial/venous catheterizations, cremaster muscle exteriorization, hemorrhage (40% total blood volume), and laparotomy. Control animals equally instrumented were not subjected to hemorrhage/laparotomy. Every 0.5 h for 4.5 h, noninvasive laser speckle contrast imaging and phosphorescence quenching were employed for nearly 7,000 flow/Po2 measurements in muscles from eight animals, using an automated system. Precise alignment of 16 muscle areas allowed overlapping between flow and oxygenation measurements to evaluate spatial heterogeneity, and repeated measurements were used to estimate temporal heterogeneity. Systemic physiological parameters and blood chemistry were simultaneously assessed by blood samplings replaced with crystalloids. Hemodilution was associated with local hypoxia, but increased flow prevented major oxygen delivery decline. Adding laparotomy and prolonged HS resulted in hypoxia, ischemia, decreased tissue oxygen delivery, and logarithmic flow/Po2 relationships in most regions. Flow and Po2 spatial heterogeneities were higher than their respective temporal heterogeneities, although this did not change significantly over the studied period. This quantitative framework establishes a basis for evaluating therapies aimed at restoring muscle homeostasis, positively impacting outcomes of civilian and military trauma/HS victims.NEW & NOTEWORTHY This is the first study on flow-Po2 relationships during normovolemia, hemodilution, and prolonged hemorrhagic shock using noninvasive methods in multiple skeletal muscle areas of monitored animals. Automated flow/Po2 measurements revealed temporal/spatial heterogeneities, hypoxia, ischemia, and decreased tissue oxygen delivery after trauma/severe hemorrhage. Hemodilution was associated with local hypoxia, but hyperemia prevented a major decline in oxygen delivery. This framework provides a quantitative basis for testing therapeutics that positively impacts muscle homeostasis and outcomes of trauma/hemorrhagic shock victims.
Collapse
Affiliation(s)
- Ivo P Torres Filho
- Damage Control Resuscitation, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| | - David Barraza
- Damage Control Resuscitation, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| | - Kim Hildreth
- Damage Control Resuscitation, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| | - Charnae Williams
- Damage Control Resuscitation, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| | - Michael A Dubick
- Damage Control Resuscitation, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, Texas
| |
Collapse
|
19
|
Rehabilitative Training Interacts with Ischemia-Instigated Spine Dynamics to Promote a Lasting Population of New Synapses in Peri-Infarct Motor Cortex. J Neurosci 2019; 39:8471-8483. [PMID: 31511430 DOI: 10.1523/jneurosci.1141-19.2019] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 08/23/2019] [Accepted: 09/02/2019] [Indexed: 11/21/2022] Open
Abstract
After subtotal infarcts of primary motor cortex (M1), motor rehabilitative training (RT) promotes improvements in paretic forelimb function that have been linked with its promotion of structural and functional reorganization of peri-infarct cortex, but how the reorganization unfolds is scantly understood. Cortical infarcts also instigate a prolonged period of dendritic spine turnover in peri-infarct cortex. Here we investigated the possibility that synaptic structural responses to RT in peri-infarct cortex reflect, in part, interactions with ischemia-instigated spine turnover. This was tested after artery-targeted photothrombotic M1 infarcts or Sham procedures in adult (4 months) C57BL/6 male and female GFP-M line (n = 24) and male yellow fluorescent protein-H line (n = 5) mice undergoing RT in skilled reaching or no-training control procedures. Regardless of training condition, spine turnover was increased out to 5 weeks postinfarct relative to Sham, as was the persistence of new spines formed within a week postinfarct. However, compared with no-training controls, new spines formed during postinfarct weeks 2-4 in mice undergoing RT persisted in much greater proportions to later time points, by a magnitude that predicted behavioral improvements in the RT group. These results indicate that RT interacts with ischemia-instigated spine turnover to promote preferential stabilization of newly formed spines, which is likely to yield a new population of mature synapses in peri-infarct cortex that could contribute to cortical functional reorganization and behavioral improvement. The findings newly implicate ischemia-instigated spine turnover as a mediator of cortical synaptic structural responses to RT and newly establish the experience dependency of new spine fates in the postischemic turnover context.SIGNIFICANCE STATEMENT Motor rehabilitation, the main treatment for motor impairments after stroke, is far from sufficient to normalize function. A better understanding of neural substrates of rehabilitation-induced behavioral improvements could be useful for understanding how to optimize it. Here, we investigated the nature and time course of synaptic responses to motor rehabilitative training in vivo Focal ischemia instigated a period of synapse turnover in peri-infarct motor cortex of mice. Rehabilitative training increased the stability of new synapses formed during the initial weeks after the infarct, the magnitude of which was correlated with improvements in skilled motor performance. Therefore, the maintenance of new synapses formed after ischemia could represent a structural mechanism of rehabilitative training efficacy.
Collapse
|
20
|
Shell JR, LaRochelle EP, Bruza P, Gunn JR, Jarvis LA, Gladstone DJ, Pogue BW. Comparison of phosphorescent agents for noninvasive sensing of tumor oxygenation via Cherenkov-excited luminescence imaging. JOURNAL OF BIOMEDICAL OPTICS 2019; 24:1-8. [PMID: 30834723 PMCID: PMC6397946 DOI: 10.1117/1.jbo.24.3.036001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/01/2019] [Indexed: 05/20/2023]
Abstract
Cherenkov emission generated in tissue during radiotherapy can be harnessed for the imaging biochemistry of tissue microenvironments. Cherenkov-excited luminescence scanned imaging (CELSI) provides a way to optically and noninvasively map oxygen-related signals, which is known to correlate to outcomes in radiotherapy. Four candidate phosphorescent reagents PtG4, MM2, Ir(btb)2 ( acac ) , and MitoID were studied for oxygen sensing, testing in a progressive series of (a) in solution, (b) in vitro, and (c) in subcutaneous tumors. In each test, the signal strength and response to oxygen were assessed by phosphorescence intensity and decay lifetime measurement. MM2 showed the most robust response to oxygen changes in solution, followed by PtG4, Ir(btb)2 ( acac ) , and MitoID. However, in PANC-1 cells, their oxygen responses differed with Ir(btb)2 ( acac ) exhibiting the largest phosphorescent intensity change in response to changes in oxygenation, followed by PtG4, MM2, and MitoID. In vivo, it was only possible to utilize Ir(btb)2 ( acac ) and PtG4, with each being used at nanomole levels, to determine signal strength, lifetime, and pO2. Oxygen sensing with CELSI during radiotherapy is feasible and can estimate values from 1 mm regions of tissue when used in the configuration of this study. PtG4 was the most amenable to in vivo sensing on the timescale of external beam LINAC x-rays.
Collapse
Affiliation(s)
- Jennifer R. Shell
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
- Address all correspondence to Jennifer R. Shell, E-mail:
| | - Ethan P. LaRochelle
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
| | - Petr Bruza
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
| | - Jason R. Gunn
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
| | - Lesley A. Jarvis
- Dartmouth College, Geisel School of Medicine, Hanover, New Hampshire, United States
| | - David J. Gladstone
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
- Dartmouth College, Geisel School of Medicine, Hanover, New Hampshire, United States
| | - Brian W. Pogue
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire, United States
| |
Collapse
|