Optics and Photonics Essential Technologies for Our Nation (2013) / Chapter Skim
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6 Health and Medicine
6 Health and Medicine
Pages 163-184
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From page 163... ...
Photonics technology plays a key role in providing the most effective, lowest-cost approaches for diagnosing, treating, and preventing disease and maintaining a healthy U.S. citizenry.3 In the nearly 15 years since the publication of the National Research Council's (NRC's)
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From page 164... ...
Non-absorbing macromolecules can be labeled using specifically engineered dyes that selectively bind to macromolecules. These dyes or biomarkers can be used in conjunction with visible and near-infrared light to highlight specific cell and tissue types, such as metastatic cancer cells cir culating in the bloodstream.
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From page 165... ...
For example, laser-based flow cytometers pro vide detailed quantification of critical blood cell types, which is one of the primary tools for diagnosing and monitoring the treatment of AIDS patients.6 In addition to allowing the physician to see what could not be seen unaided, state-of-the-art optical technologies increase the sensitivity and specificity of mea surements far beyond the physician's sense of taste, smell, hearing, and touch.7 Photonics plays a major role in many modern molecular diagnostic instruments. Optical technologies now provide precise measurements of blood serum chemistry for maintaining safe glucose levels in patients with diabetes, replacing urine taste tests.8 Kidney function tests rely on accurate optical measurements of the glo merular filtration rate (GFR)
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From page 166... ...
In low-income countries, infectious diseases, such as tuberculosis, malaria, and AIDS, remain leading causes of death. This is due in large part to the absence of low-cost diagnostic tests that can detect these diseases at an early stage when the infections can be more easily contained and cost-effective intervention strategies can be employed.
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From page 167... ...
New technology using lasers has the potential to provide a fast method for identifying drugs by exposing the pills to laser light and observing the spectra emitted in re sponse to the laser excitation. The colors emitted by the sample provide a unique fingerprint, which can be compared with a database of more than 5,000 common pharmaceuticals to determine the precise makeup of the patient's prescription and to determine quickly whether these drugs contributed to the patient's condition.11 In the surgical suite, brain damage occurs in less than 5 minutes in anesthetized patients during surgery if sufficient oxygen levels are not maintained.
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From page 168... ...
Almost everyone has had blood drawn and sent to the clinical laboratory for blood tests, but few people are aware that these blood samples are analyzed using lasers and optical imaging to provide the measurements characterizing the status of the patient's blood and circulatory system. Many types of blood cells have distinct shapes and unique internal structures, which can be detected by illuminating the cells with a laser beam and analyzing the transmitted and scattered laser light.
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From page 169... ...
New optical sources and materials, imaging devices, microfluidic technologies, and detection methods will provide remarkable increases in speed, sensitivity, and precision for biomedical optical instrumentation. Nucleic Acid Sequence Detection and Mutation Detection Predilections for many diseases are the result of the specific makeup of an in dividual's inherited genetic code.
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From page 170... ...
Time to sequence a single human genome with (a) pre-laser DNA sequencers (1970s)
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From page 171... ...
Proteomic Analysis Through Protein and Tissue Arrays Detecting cancer recurrence early, determining the most appropriate drug therapy to slow tumor growth, and detecting and/or diagnosing a number of deadly infectious diseases are all examples of diagnostic tests that rely on measuring specific proteins in the blood serum. Recent advances in protein detection using photonics technology platforms are providing dramatic increases in sensitivity and specificity.
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From page 172... ...
This high-throughput screening technology relies on robotic sample-handling automation for the precise and rapid parallel processing of multiple samples as well as on optical technology for high-speed quantitative data collection. Optical methods, including fluores cence, bioluminescence, and colorimetry, are used to identify and count viable and nonviable cells affected by the candidate compounds, determine activated molecular pathways in target cells, and detect the overall cellular response to po tential small-molecule drugs.
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From page 173... ...
This single protein in turn binds a fluorescent enzyme that creates a fluorescent signal localized in the well, which is detected by laser scanning the well array. This approach allows very low concentrations of proteins to be detected by actually counting the protein molecules individually.
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From page 174... ...
Understanding the complex processes that make up an immune response requires the simultaneous monitoring of the activity and con centration of dozens of immune-system cell types. Lasers have traditionally been used in flow cytometer instruments to evaluate patient blood samples, identifying and counting the immune-system cell types.
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From page 175... ...
FIGURE 6.5 (a) A CyTOF instrument, which extends the capability of multi-parameter flow cytometry by atomic mass spectrometry to measure up to 100 biomarkers simultaneously in single cells at a rate of 1,000 cells per second; (b)
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From page 176... ...
Using OCT guidance, femtosecond lasers can be precisely focused on the capsule and automatically cut close to perfectly round incisions in the capsule. These precise incisions greatly assist in locating and centering the replacement lens.
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From page 177... ...
a laser capsulotomy with clearly improved boundaries of lens capsule cutting with optical coher ence tomography (OCT) -guided femtosecond laser surgery.
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From page 178... ...
Nature Biotechnology 29:352-356. and lymph nodes that may need to be carefully avoided or excised as part of the operational procedure.25 Dual Energy CT and Quantitative Image Analysis The primary causes of death in the United States today are heart disease, cancer, and pulmonary disease, such as emphysema.26 In all of these modern ailments, early detection is the key to effective intervention.
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From page 179... ...
The x ray photon sources, the optics for focusing the x rays, and the detectors used to detect the x ray photons are designed employing many of the same techniques developed for the design of imaging instruments using visible light. Similarly, the mathematical methods for analyzing the raw trans mitted x ray data, for reconstructing and visualizing three-dimensional models of internal anatomy, are almost identical to comparable techniques employed in other imaging modalities using visible or infrared light.
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From page 180... ...
As defined by Carl Deisseroth, one of its primary developers: "Optogenetics is the combination of genetic and optical methods to achieve gain or loss of function of well-defined events in specific cells of living tissue."31 This technique has seen primary application in neuroscience, where the function of single neurons or groups of neurons can be monitored and controlled by specific wavelengths of light. Neurons in live, behaving animals can be genetically programmed to fire or be prevented from firing by exposure to dif ferent colors of light.
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From page 181... ...
This research has important ramifications on the engineering of tissue structures to support the appropriate growth of specific cell types for organ transplantation. FINDINGS Key Finding: Many chronic, debilitating, and often fatal degenerative diseases impacting the aging population are mediated or exacerbated by the patient's own immune system.
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From page 182... ...
Finding: Optical techniques using solid-state light sources and detectors com bined with microfluidics are the ideal technology base for automated, low-cost, portable devices that can be operated by personnel without their needing extensive training. In high-income countries the primary causes of death and patient mor bidity are degenerative diseases due to longer life expectancy; in contrast, in low income countries the infectious diseases remain leading causes of death.
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From page 183... ...
optics and photonics community should develop new instrumentation to allow simultaneous measurement of all immune-system cell types in a blood sample. Many health issues could be addressed by an improved knowledge of the immune system, which represents one of the major areas requir ing better understanding.
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From page 184... ...
at which critical developments combining medical and engineering discoveries can be efficiently fostered. Recommendation: The U.S.
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