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Assessing and responding to sudden deterioration in the adult
Published in Nicola Neale, Joanne Sale, Developing Practical Nursing Skills, 2022
The T wave represents ventricular repolarisation. It is normally a gradual upstroke and a rapid downstroke. The T can however be affected in some individuals, for example, those who have ischaemia of the myocardium or coronary heart disease. Changes in this wave require further investigation and treatment.
Blast Injuries
Published in Ian Greaves, Keith Porter, Jeff Garner, Trauma Care Manual, 2021
Ian Greaves, Keith Porter, Jeff Garner
The shock wave is analogous to a sound wave in that it passes through substances rather than moves them. A shock wave is only produced as a result of a high-energy explosions and is typically not a feature of low-energy ‘home-made’ explosives. The schematic shown in Figure 26.1 illustrates the shock wave propagating spherically from the point of the explosion.
Radiation Safety
Published in Debbie Peet, Emma Chung, Practical Medical Physics, 2021
Debbie Peet, Elizabeth Davies, Richard Raynor, Alimul Chowdhury
As the name suggests, phototherapy ultraviolet (UV) electromagnetic wave radiation is used to treat skin conditions. Broadband UV (UVB) light uses wavelengths ranging from 280 nm to 314 nm to treat conditions such as psoriasis and eczema. Narrowband UVB uses a narrower part of the spectrum (311 nm to 312 nm), which is found to be more effective than broadband UVB for treating severe dermatological cases. PUVA therapy (psoralen + UVA) uses the UVA part of the spectrum (315 nm to 400 nm) with a photosensitising drug, called psoralen, added to treat psoriasis, vitiligo, and cutaneous T-cell lymphoma. The drug is administered as a cream to the skin or orally. Phototherapy is widely available, although audits have shown enormous variations in the quality of service and incidence of injury.
Microfluidics in drug delivery: review of methods and applications
Published in Pharmaceutical Development and Technology, 2023
Mutasem Rawas-Qalaji, Roberta Cagliani, Noor Al-hashimi, Rahma Al-Dabbagh, Amena Al-Dabbagh, Zahid Hussain
Light is an electromagnetic wave that can be synchronized, focused, and amplified to give rise lasers whose level of energy can be manipulated by the application of microfluidic technology. Thus, stress applied to cells via the optical energy can be exploited to deliver genetic materials into living cells using an optical transfection (Stevenson et al. 2010). Additionally, not only could the optical energy be used as a source of stress that disturbs the cell membranes, it could also act as tweezers that facilitate transfection of macromolecules, NPs and microspheres into living cells (Stracke et al. 2005; Arita et al. 2011; Tanaka and Terakawa 2011). As a result of improved transfection of micro- or NPs loaded with genetic materials, site-specific release of genetic materials within the cells can be optimized by using the lasers (Figure 13).
Brugada syndrome
Published in Acta Cardiologica, 2021
Haarika Korlipara, Giridhar Korlipara, Srinivas Pentyala
The 12-lead electrocardiogram (ECG) is used to measure electrical activity within the heart. It can quantify depolarisation and repolarization of the myocardium by recording changes in voltage. Zero (baseline) voltage signifies that the heart is either fully depolarised or repolarized [4]. Although the appearance of ECG tracing can differ among the leads in terms of positive and negative deflections, several specific components are common amongst all the leads. An example is the first small deflection from the baseline voltage known as the P wave, which signifies atrial depolarisation [5]. The next wave is known as the QRS complex and this represents ventricular depolarisation; atrial repolarization is masked by the much larger voltage changes in this complex [5]. The time interval between the P wave and the QRS complex represents the conduction delay that occurs within the AV node. Lastly, the final wave is the T wave, which represents ventricular repolarization and takes longer compared to ventricular depolarisation [5] (Figure 1). The interval between the QRS complex and T wave represents the time it takes for the entire ventricle to be depolarised. The sequence of ventricular repolarization differs from depolarisation in that; the last cells to depolarise are the first cells to repolarize. This is referring to the cells in the subepicardial region (below the outer layer of the ventricular wall) which are the last cells to depolarise, and they repolarize first because they have shorter action potential durations compared to subendocardial cells (inner region) [6].
Analysis of membrane permeability due to synergistic effect of controlled shock wave and electric field application
Published in Electromagnetic Biology and Medicine, 2020
Shadeeb Hossain, Ahmed Abdelgawad
Application of shock waves for pressure-induced membrane permeability and transient pores is an area of active research Gregory et al. (Koshiyama et al. 2006; Vedadi et al. 2010). A shock wave is a wave that is moving faster than the speed of sound in a medium. The interaction of a controlled shock wave with a cell membrane has the potential to increase its permeability (Gambihler et al. 1992). However, the mechanism of the change in permeabilization in the cell membrane is still an area of active research (Ohl et al. 2003). Shock waves are single high-pressure pulse waves that are generated in the range of MPa and have several applications in the treatment of kidney stones (Delius 1994) and gene transfer (Lauer et al. 1997). Similarly, shock waves have application in cardiology to treat coronary artery disease, wound, and musculoskeletal disorders, including tendon pain, jumper’s knee, calcified shoulder, plankton fasciitis and non-unions of bone fracture (Loske 2017; Ogden et al. 2001; Wang et al. 2018)