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Imaging as an Important Tool for Diagnosis of Breast Cancer
Published in Shazia Rashid, Ankur Saxena, Sabia Rashid, Latest Advances in Diagnosis and Treatment of Women-Associated Cancers, 2022
Priyanka Mudaliar, Shafina Siddiqui, Sangeeta Ballav, Narrayan Raam Shankar, Soumya Basu, Jyotirmoi Aich
CTLM is an optical imaging technology used to test for breast cancer in women under the age of 40 having dense breasts [10–11]. CTLM assesses tissue optical characteristics using near-infrared light propagation through the tissue. For each wavelength, various tissue factors can affect dispersion and absorption properties [11]. Imaging Diagnostic Systems, Inc. (IDSI, United States) owns the CTLM trademark for its optical tomographic technology for female breast imaging. It was designated as a Class III medical device in 2011. It is now being evaluated by the Food and Drug Administration (FDA) in the United States and is being proposed as a mammography adjunct [12].
Principles of Doppler ultrasound
Published in Joseph A. Zygmunt, Venous Ultrasound, 2020
The wavelength is an important parameter in ultrasound for two principle reasons. First, the wavelength helps determine the detail resolution of an image. In general, a shorter wavelength results in better image resolution. This is one reason why using a higher transmit frequency results in better image resolution. Second, the wavelength helps determine the type of reflection that occurs from various tissues and structures. When the surface of a structure is large and smooth relative to the wavelength, very angle-dependent specular reflection occurs. When the surface is rough with respect to the wavelength, the much less angle-dependent (back) scattering occurs. When the structure is very small relative to the wavelength, as is the case with red blood cells, Rayleigh scattering occurs.
Introduction
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
The speed of sound is constant in a given medium; in other words, the waves travel at a constant speed through a homogeneous medium. This is dependent on the mechanical properties of the medium, principally the density and the elasticity of the substance. Speed is measured in units of distance per unit time, i.e. ms-1. The speed of sound in formulae is generally represented by v for velocity or c for constant. The wavelength is the length of a complete wave pattern, or the distance between two successive wavefronts. It is measured in units of distance, and represented by the symbol λ, the Greek letter L, for length.
Next-generation viral nanoparticles for targeted delivery of therapeutics: Fundamentals, methods, biomedical applications, and challenges
Published in Expert Opinion on Drug Delivery, 2023
Jia Sen Tan, Muhamad Norizwan Bin Jaffar Ali, Bee Koon Gan, Wen Siang Tan
Photo-thermal therapy has gained attraction over the years for treatment of various cancers. This treatment exposes patients to elevated temperature or light source with high energy wavelength, which sensitizes the cancer cells toward chemotherapeutic agents. MrNV VLP loaded with DOX released the drug for an extended period at 43°C, which significantly improved the treatment efficacy toward HT29 colorectal cancer cells when used in conjunction with FA as a targeted delivery ligand [55]. This temperature weakened the protein–protein and protein–RNA interactions of MrNV VLP, which allowed the DOX to leak out from the internal cavity of the VLP either by passing through the void between the capsid proteins, or rupture of the VLP [55]. In addition, VLPs could be utilized as a vehicle for photo-thermal dynamic therapy. In this capacity, VLPs loaded with photo thermal sensitive agents, which generate heat upon exposure to heat and light of near infrared spectra (700–1100 nm), could kill cancer cells by heat ablation or inflammation reactions, such as those caused by damage associated molecular patterns (DAMP). Recently, Shahrivarkevishahi et al. [228] demonstrated that the Qβ VLP conjugated with the near-infrared absorbing croconium dye generated heat effectively upon irradiation by NIR laser source, and elicited mild immunogenic effects too. This innovative photo-thermal VLP suppressed the growth of primary breast cancer in the tumor-bearing mice, and significantly increased their survival rate.
ALSUntangled #60: light therapy
Published in Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration, 2022
Richard Bedlack, Paul Barkhaus, Ben Barnes, Michael Bereman, Tulio Bertorini, Gregory Carter, Jesse Crayle, Sky Kihuwa-Mani, Robert Bowser, Pamela Kittrell, Christopher McDermott, Gary Pattee, Kristiana Salmon, Paul Wicks
Light is a type of electromagnetic radiation, which comes in discrete quantized packages known as photons (5). It can be characterized according to its wavelength (measured in nanometers, nm). Visible light has wavelengths between 400 and 700 nm. Light with wavelengths below this range is referred to as “ultraviolet”, and light with wavelengths above this range is referred to as “infrared” (5). Light can be generated by different sources (ex. lamps, LEDs, lasers). In addition to having different wavelengths, these different sources can deliver different amounts of energy (measured in joules, J) and power (measured in watts, W). When describing power or energy, it is important to state the area the energy is delivered over. This is called “power density” or “irradiance” (measured in milliwatts per square centimeter; mW/cm2) and/or “energy density” or “fluence” (measured in joules per square centimeter; J/cm2, 5,6).
Residence time and mixing capacity of a rotary tablet press feed frame
Published in Drug Development and Industrial Pharmacy, 2021
Maren Zimmermann, Markus Thommes
The measurement was conducted in reflectance mode. Thereby the reflected light intensity was compared to the initial emitted light intensity. The ratio as a function of the wavelength was called spectra. In all cases, a white tablet consisting of the model formulation served as reference on which the system was calibrated a priori. Therefore, the conducted determination of the light intensity ratio defined as reflection rate R was a relative measurement. R was attenuated by the weight fraction of the UV-sensitive tracer (theophylline) (Figure 2, left). For further processing, the absorbance was calculated from the reflection rate R by using the Schuster–Kubelka–Munk equation (Equation (10)) at the maximum molar attenuation coefficient (272 nm). The equation was found for calculating absorption and scattering of light on solid layers [36].