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Evaluation of the proper level of specific absorption rate of human blood for 532a??nm laser in blood low-level laser therapy
摘要： Low-level laser has been used for a variety of clinical applications as a practical non-medicinal treatment, due to its ability to modulate blood rheology and improve biostimulation. This article research aim was to evaluate the proper level of specific absorption rate (SAR) of human blood during low-level laser treatment. Measurements were conducted on human blood in vitro, at different laser powers (wavelength 532 nm at powers of 50, 60, 70 and 80 mW) and exposure duration. Dielectric parameters were observed as a function of frequency from 40 Hz–30 MHz by utilizing an Agilent 4294A impedance analyzer at average room temperature of 25 °C. The SAR increased steadily with increasing frequency until it attained saturation peak, and thereafter exhibited a decrease trend. The SAR values range from 0.173–1.417 W kg?1 for blood irradiated using laser power of 50 mW and range from 0.178–0.754 W kg?1 for 60 mW. These values of SAR within 5–10 min of radiation present better stimulation results. Using laser powers of 70 and 80 mW for irradiations, the SAR values within the range from 0.003–0.791 W kg?1 and 0.130–0.491 W kg?1, respectively, were computed. The SAR values here portend high risk associated to blood than its stimulation mechanism because the blood already attained a plateau and became saturated. This causes imbalance within the blood molecules resulting in a decrease in SAR as the frequency increases. This is due to a phase lag that develops between the electric field and induced dipole alignment creating a significant drop in the SAR of blood. The rate of inhibition increases rather than stimulation since the thermal radiation becomes exceedingly high resulting in crenation and hemolyzation of the blood. Therefore, we recommend using a laser at an output of power 50 mW for 5–10 min to reach the maximum capacity of SAR for more absorption and optimal stimulation.
关键词： impedance analyzer,specific absorption rate (SAR),acceptable maximum limit,blood-laser therapy,human blood
更新于2025-09-19 17:13:59
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Do Infrared Molecular Fingerprints of Individuals Exist? Lessons from Spectroscopic Analysis of Human Blood
摘要： Genetic, lifestyle and environmental factors, along with development and aging impact molecular composition of human blood. Although many diseases leave their trace in blood, the question is whether this trace can be robustly and reproducibly measured and used for health monitoring of a given adult population. Infrared molecular spectra of blood serum can be obtained in a non-invasive, time- and cost-efficient manner, delivering molecular information from all molecular species within the highly complex samples. We demonstrate that broadband infrared spectroscopy can be used for reproducible molecular fingerprinting of human blood. To evaluate whether certain medium is sufficiently robust to facilitate detection of disease onset, the quantitative extent of variability of a person as well as a reference population needs to be evaluated. If within-person variability would exceed that of the between-personal variability in a reference population, the approach would not be suited for disease detection. To assess the extent of uniqueness of infrared molecular fingerprints as well as their biological variability, we performed a comprehensive prospective longitudinal study collecting blood samples of 27 healthy individuals donating blood at 8 consequent intervals. We apply broadband infrared molecular fingerprinting by Fourier transform infrared spectroscopy (FTIR) and analyse between-person and within-person variability based on all different molecular classes in the blood simultaneously. We report experimental evidence of the feasibility of identifying a person within a group of individuals based on her/his infrared molecular fingerprint, similarly to metabolic fingerprints [1]. In a first step, using standard methods for descriptive analysis we observe that the between-person variability is larger than the within-person variability by a factor of 3 (Fig.1 Left). This observation opens up the possibility for disease detection. In a second step, we combine standard dimensionality-reduction methods, such as principal component analysis (PCA), and several high-accuracy machine-learning algorithms [1] (random forests, extreme gradient boosting, k nearest neighbours) for deriving classification rules, which we then use for making predictions on test sets of unseen data. For a group of 7 donations that span a period of 6 weeks, we reach peak classification accuracy of above 95% (Fig.1 Right), while the accuracy of a classifier predicting in random would have been as low as 3.7%. In addition, we evaluate the underlying spectral features with respect to their importance on signalling separation and in this way identifying the human blood serum constituents associated with between-person variation. Observed robustness of infrared molecular fingerprints suggests their applicability for health and treatment monitoring.
关键词： infrared molecular fingerprints,FTIR,health monitoring,human blood,spectroscopic analysis
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Field-Resolved Infrared Spectroscopy of Human Blood to Tackle Lung, Prostate and Breast Cancer Detection
摘要： Broadband mid-infrared spectroscopy of biofluids carries great potential for biological and biomedical applications, as it provides fast, reliable and label-free access to the molecular composition of the sample. When applied to human blood serum, a range of molecular contents can be quantified and specific changes in the absorption spectra, driven by diseases (e.g. cancer) can be identified and used for diagnostic purposes. One remaining challenge is the complexity of human serum: physiological phenotypes are driven by minor changes in concentration of thousands of different molecules. At the same time, although many low-abundance molecules are very informative for disease detection, these are often not detectable with conventional Fourier-Transform Infrared (FTIR) spectroscopy and quantum-cascade laser (QCL) based approaches due to a lack of sensitivity and specificity. Here we show how field-resolved spectroscopy (FRS) of few-cycle-excited molecular vibrations can be utilised to address these shortcomings and demonstrate its applicability for the measurement of human blood serum in a clinical setting. In a preparatory experiment, we quantitatively investigate the ability of FRS to detect small changes in the sample response by spiking blood serum with a defined concentration of dimethyl sulfone (DMSO2). We demonstrate that FRS is able to detect changes in molecular concentration down to the sub-μg/ml level in human blood serum, outperforming the sensitivity of FTIR- and QCL-based approaches. Hence, the smallest changes currently detectable by FRS are five orders of magnitude below the concentration of the most highly-abundant molecules in blood, implying a detectable concentration dynamic range of 105. Based on these results, we apply FRS for the first time in a real-world setting, a clinical study with a well-matched cohort of 195 control individuals and 58 lung, 41 prostate and 42 breast cancer patients and compare the obtained results to state-of-the-art FTIR measurements of the same samples. Corresponding infrared molecular fingerprints were recorded as time-domain sampled field oscillations emerging from the excited molecules in the serum samples (Fig. 1a). We find that investigation at different time windows (Fig. 1c-d) reveals a distinct temporal response of the samples originating from controls as compared to lung cancer patients. Preliminary analysis of the time-domain data with a random forest classifier reveals a high detection accuracy for cancer detection. Even though FRS, in this early stage of development, has considerably smaller spectral coverage as compared to FTIR, it reaches a similar rate of cancer detection efficiency. This suggests that the next generation FRS, with several octave spectral coverage, holds promise for outperforming FTIR fingerprinting substantially.
关键词： cancer detection,molecular vibrations,field-resolved spectroscopy,infrared spectroscopy,human blood
更新于2025-09-11 14:15:04
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Liquid crystal-based aptasensor for the detection of interferon-γ and its application in the diagnosis of tuberculosis using human blood
摘要： We report the development of a liquid crystal (LC)-based aptasensor for the detection of interferon-γ (IFN-γ) in human blood as well as the diagnosis of tuberculosis (TB). In this system, the binding of IFN-γ to an aptamer immobilized on a surface disrupts the orientation of LCs, inducing a transition from a homeotropic orientation to a random one. This change in the orientation of the LCs can easily be converted and observed as a shift from a dark optical LC image to a bright one under a polarized light microscope. Through this sensing mechanism, IFN-γ levels as low as 1 pM (17 pg/ml) could be detected. This LC-based aptasensor was employed for the diagnosis of TB using blood samples from patients with latent TB. With this LC-based approach, not only could IFN-γ readily be detected, but also latent TB could be diagnosed using human blood simply and effectively without any intricate processes or instrumentation. Therefore, our present research provides a promising IFN-γ sensor with applications in clinical diagnosis of various infectious diseases, and in immunological research.
关键词： Tuberculosis (TB),Interferon-γ (IFN-γ),4-cyano-4′-pentylbiphenyl (5CB),Liquid crystal (LC),Aptamer,Human blood sample
更新于2025-09-09 09:28:46
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[IEEE 2018 International Conference on Applied Engineering (ICAE) - Batam, Indonesia (2018.10.3-2018.10.4)] 2018 International Conference on Applied Engineering (ICAE) - Identification Of Leukemia Diseases Based On Microscopic Human Blood Cells Using Image Processing
摘要： White blood cell cancer or what is often referred to as leukemia is a very dangerous disease. Until now the process of recognizing white blood cell cancer or leukemia is still done conventionally, which method can cause a diagnosis difference if done by different medical personnel. To answer these problems, a desktop-based application will be built. This application is made to help the process of identification and classification of types of leukemia using the technique of processing microscopic images of human blood cells. By doing several approaches, such as pre-processing, using the median filtering method, conversion color (RGB to HSV) to clarify the blood image and tresholding to get the image pattern of blood cells that have. Segmentation will be carried out to separate between objects that will be taken with unnecessary objects. This system will use extracted form features from each cell in microscopic blood images. This feature retrieval will be used as a classifier input which is divided into two classification classes, namely Acute Lympotic Leukemia (ALL) and Acute Myolegenous Leukemia (AML). With this method an accuracy of 80% can be generated for the detection of ALL cells separately (one cell), 100% for AML detection separately (one cell) and 90% for cell detection throughout (many cells).
关键词： Leukemia,Image Processing,Human Blood Cells,Microscopic
更新于2025-09-04 15:30:14