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The Emerging Role of Exosome Nanoparticles in Regenerative Medicine
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Zahra Sadat Hashemi, Mahlegha Ghavami, Saeed Khalili, Seyed Morteza Naghib
Raman spectroscopy is a spectroscopy light scattering technique and identifies the vibrational states of sample particles. The laser light interacts with particles and results in a shift in the energy of the laser photons. Finally, it gives molecular fingerprints and bond structures of the sample. According to this approach, the chemical composition of EV will be achieved (for example human urinary exosomes were reported (Tatischeff et al. 2012)).
Understanding the Role of Existing Technology in the Fight Against COVID-19
Published in Ram Shringar Raw, Vishal Jain, Sanjoy Das, Meenakshi Sharma, Pandemic Detection and Analysis Through Smart Computing Technologies, 2022
Raman spectroscopy is another highly sensitive and useful vibrational spectroscopy technique that allows non-destructive and real-time analysis of biological samples. A Raman spectrum is obtained by the process of scattering of light, whereas in FTIR, it is obtained by absorption of light by the matter. When a monochromatic (laser source) light is incident on the sample, the light may interact with the material either elastically or inelastically. In the elastic scattering, the incident photon is absorbed and reemitted with the same energy (frequency). This is known as Rayleigh scattering. On the other hand, in an inelastic scattering, the absorbed photon may be emitted with frequency higher or lower than the incident photon. The probability of inelastic scattering is very small compared to the Rayleigh scattering. The process of light scattering is shown in Figure 2.4. When the frequency of emitted photon (ν2) is less than the incident frequency (ν1), it is known as Stokes Raman scattering. When the frequency of emitted photon (ν2) is more than the incident frequency (ν1), it is known as anti-Stokes Raman scattering. This phenomenon is known as the Raman effect, and the observed effect is specific to the molecules causing the scattering. Thus, the Raman signals are used for determining the presence of molecules and their states using the inelastic scattering.
The skin’s endogenous antioxidant network
Published in Roger L. McMullen, Antioxidants and the Skin, 2018
Overall, the levels of ascorbate, urate, alpha-tocopherol, and coenzyme Q are relatively high in skin.53 Twice as much GSH is found in the epidermis than in the dermis; however, the ratio of GSSG/GSH is four times higher in the dermis than the epidermis.53 Thus, the epidermis is either much more efficient at maintaining the level of GSH, or GSH utilization is much greater in the dermis than the epidermis. In regard to carotenoids, the most common ones found in skin include carotenes (alpha-, beta-, and gamma-), lycopene, lutein, and zeaxanthin.54 They are obtained in the diet and found distributed in the dermis and epidermis. Carotenoids find their way to the epidermis by way of adipose tissue (where they are stored), blood, or lymph. In addition, they may be secreted by sweat or sebaceous glands.26 At any rate, carotenoids play an important role in the protection of skin from the elements. The anatomical distribution of antioxidants may also vary from one site to the next. For example, Darvin and coworkers were able to discern distinct distributions of carotenoids in several tested anatomical locations including palm, forehead, and volar forearm.55 Their studies were conducted in vivo on human subjects with Raman spectroscopy. Overall, clinical studies indicate that the levels of endogenous antioxidants are greatly influenced by both diet and exposure to stress.56
Role of necroptosis of alveolar macrophages in acute lung inflammation of mice exposed to titanium dioxide nanoparticles
Published in Nanotoxicology, 2021
Tomoya Sagawa, Akiko Honda, Raga Ishikawa, Natsuko Miyasaka, Megumi Nagao, Sakiko Akaji, Takashi Kida, Takahiro Tsujikawa, Tatsushi Yoshida, Yutaka Kawahito, Hirohisa Takano
Although it has been reported that TiO2 nanoparticles are phagocytosed by macrophages in the lung, and electron microscopy is the standard method for determining the localization of TiO2 nanoparticles in cells (Xu et al. 2010; Numano et al. 2014; Abdulnasser Harfoush et al. 2020), electron microscopy requires pretreatment to observe biological samples and is difficult to combine with other assays. Raman spectroscopy is a low-invasive technique that allows for chemical analysis by optical means without reagents, staining, or sample preparation, and enables nondestructive, label-free measurement of the chemical composition of complex biological samples such as body fluids, cells, and tissues (Bourbousson et al. 2019). Raman spectroscopy has been used to examine the localization of TiO2 nanoparticles in lung cells (Nakajima et al. 2011; Li et al. 2013) but has not been combined with other assays for the same sample. In this study, the combination of Raman spectroscopic imaging with HE staining, immunostaining, and Diff-Quick staining clearly showed that AMs phagocytosed TiO2 nanoparticles. Applying multiplex immunohistochemical analysis (Tsujikawa et al. 2017), which can be used in combination with immunostaining of more markers, may reveal the relationship between the intra/extracellular localization of particles and a variety of biological responses temporally and spatially. This technique can also be applied in various fields for pathology and histology analyses.
Joint modeling of longitudinal change in tumor cell level and time to death of breast cancer patients: In case of Ayder comprehensive specialized Hospital Tigray, Ethiopia
Published in Cogent Medicine, 2021
Bsrat Tesfay, Tewodros Getinet, Endeshaw Assefa Derso
High proportion of breast cancer morbidity and mortality was observed in age category of 15 years of age and above in both men and women in Tigray, Northern Ethiopia. Overall breast cancer mortality was 2.3% during the study period (Ajemu et al., 2019). Translating Raman spectroscopy technology by using the RESpect probe as a potential point-of-care screening instrument has the potential to change the paradigm of screening for cancer as an initial step to determine when a definitive tissue biopsy would be necessary (Agsalda-Garcia et al., 2019). The profile of a cancer patient includes summarization and visualization of the results of WES and RNAseq analysis (specific variants and significantly expressed genes, respectively) and the clinical profile, integration/comparison of these results and a prediction regarding the disease trajectory (Kosvyra et al., 2019).
A look into the use of Raman spectroscopy for brain and breast cancer diagnostics: linear and non-linear optics in cancer research as a gateway to tumor cell identity
Published in Expert Review of Molecular Diagnostics, 2020
Halina Abramczyk, Beata Brozek-Pluska, Arkadiusz Jarota, Jakub Surmacki, Anna Imiela, Monika Kopec
Raman spectroscopy-based diagnostics and imaging offer many advantages over the routine clinical techniques noninvasiveness, tissue removing is not required, minimal sample processing, labeling is not required, no prior knowledge to target molecules (e.g. antibodies) is required, safety, nonionizing electromagnetic field is used, no external dyes/contrast agents are needed to produce human organs images. The method is faster and cheaper to perform, which will result in quicker patient diagnosis, fewer time delays, less pain, and trauma of patients, less cost to the hospital. Raman based methods with the sensitivity and specificity of over 90% for in vivo and ex vivo measurements might be applied to clinical practice with a positive economic impact due to reducing of false biopsy and risk of incomplete tumor resection.