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The Role of Botanicals in Cardiovascular Health
Published in Stephen T. Sinatra, Mark C. Houston, Nutritional and Integrative Strategies in Cardiovascular Medicine, 2022
While it is beyond the scope of this chapter to discuss quality, clinicians should be cognizant of the tremendous variability that exists for botanical products in the marketplace. Products that have been studied in controlled clinical trials are generally of higher quality and should be recommended when possible. Using clinically tested products also allows clinicians to recommend an effective dose based upon study results.
Radiation Protection of the Patient
Published in W. P. M. Mayles, A. E. Nahum, J.-C. Rosenwald, Handbook of Radiotherapy Physics, 2021
W. P. M. Mayles, Uwe Schneider
Manufacturers are required to display the estimated value of CTDIvol on the CT console for each patient scan. It indicates the average dose to the scanned area, but to enable estimation of the detriment from scanning, the CTDI is multiplied by the scan length to give the dose length product (DLP), also displayed on CT consoles. Using the DLP, it is possible to calculate the effective dose (see Section 58.1.3) associated with the scan. It is pointed out by Shrimpton et al. (2009) that effective dose is intended as a way to assess the impact of radiation on a population for radiation protection purposes. Its use in CT scanning should be limited to the assessment of ‘typical doses to reference patients from standard protocols'. If the risk to an individual patient is required, the dose to the relevant organs can be calculated and the risk calculated using age- and sex-specific data from publications such as Committee on the Biological Effects of Ionizing Radiation (BEIR) VII (BRER 2006, see also Section 58.2.9). AAPM Report 96 (2008) suggests that in practice, the effective dose gives a useful approximate indication of the risk, but it should not be quoted to more than 1 or 2 significant figures to emphasise the uncertainty.
Radiation protection
Published in Damian Tolan, Rachel Hyland, Christopher Taylor, Arnold Cowen, Get Through, 2020
Damian Tolan, Rachel Hyland, Christopher Taylor, Arnold Cowen
True – e.g. a typical PA chest x-ray entrance dose is 0.2 mGy, and the effective dose 0.02 mSv. effective dose is calculated from the absorbed doses to the various tissues in the body. Some of these will lie outside the radiation beam and receive very little dose. even those in the main beam will receive a dose smaller than the entrance dose because of attenuation.True – typical values for a chest x-ray are 0.2 mGy compared with 4–10 mGy for a lumbar spine.False – thermoluminescent dose meters are used when necessary for this.False – skin dose alone does not allow calculation of the effective dose. However, it is a good predictor of deterministic (non-stochastic) effects.True – as x-ray output increases directly with mAs.
Chromosome aberrations, micronucleus frequency, and catalase concentration in a population chronically exposed to high levels of radon
Published in International Journal of Radiation Biology, 2023
Dwi Ramadhani, Sofiati Purnami, Devita Tetriana, Irawan Sugoro, Viria Agesti Suvifan, Nastiti Rahadjeng, Septelia Inawati Wanandi, Heri Wibowo, Ikuo Kashiwakura, Tomisato Miura, Mukh Syaifudin
Details about the measurements of indoor radon concentration can be found in Nugraha et al. (2021). Briefly, four series of radon level measurements were conducted in 2018–2019. The measurements were performed using solid-state nuclear track detectors (SSNTDs), Raduet® (Radosys, Ltd, Hungary). Passive detectors (CR-39) were placed in the house of each participant. After three months of exposure, CR-39 was chemically etched for 24 h in 6 M NaOH at 60 °C. Radon concentrations were then calculated using the alpha track densities identified under an optical microscope. The annual effective dose for each subject was obtained from raw data and calculations available in Nugraha et al. (2021). In brief, the annual effective dose was defined as the total exposure of an individual to both external and internal sources. External exposure originates from environmental gamma radiation, whereas internal exposure comes from ingestion and inhalation. Lastly, the cumulative dose was calculated by multiplying the annual effective dose by the age of each individual.
Implantable drug delivery systems for the treatment of osteomyelitis
Published in Drug Development and Industrial Pharmacy, 2022
Megan Smith, Matthew Roberts, Raida Al-Kassas
The use of antibiotics encapsulated within nanoparticles (NPs) has proven to be very successful in the treatment against antibiotic resistant bacteria. NPs allow for a high concentration of drug to be directly delivered and held at the site of infection. They reduce the potential for the drugs to be cleared from the body and so the chance for an effective dose is increased. Nanoparticle drug delivery systems offer enhanced drug solubility, modulate the drug release kinetics, prevent clearance by the immune system, are able to deliver multiple drugs to target at once and can provide targeted drug delivery to the site of infection [115]. NPs are more desirable over other structures due to their small controllable size, large surface area to mass ratio, possess a structure that can be easily functionalized and high reactivity [116]. NPs can come in the form of liposomes, polymeric nanoparticles, dendrimers and other inorganic nanoparticles such as metal nanoparticles; these can be seen in Figure 9.
Bi-phasic dose response in the preclinical and clinical developments of sigma-1 receptor ligands for the treatment of neurodegenerative disorders
Published in Expert Opinion on Drug Discovery, 2021
S1R drugs, by activating a cellular modulatory system, present few side-effects related to the target itself. ADME parameters, off-targets and target engagement must be assessed. An important issue remains the adequate concentration or dose of the ligand required to induce an optimal effect. The effective dose selection relies on numerous interacting factors related to the pathology, patient history and dosage form. In the case of S1R drugs, the target itself is an additional factor. Among clinical trials reported so far, igmesine was found effective at low dose of 25 mg oral daily in depression [116]; blarcamesine was used in AD trial at doses of 30–50 mg oral daily [161]; and pridopidine 45 mg bid shows most beneficial effects in HD patients [NCT02006472]. These observations show at the clinical level that the definition of the optimal active dose for a S1R agonist must be carefully addressed. Determining the most adequate effective dose in patients is essential for assessing the optimal therapeutic efficacy of the S1R compounds in neurodegenerative diseases.