The cell and tissues
Peate Ian, Dutton Helen in Acute Nursing Care, 2020
Before considering the basic structure of the cell, it is important to consider its physiological environment. All human cells contain an aqueous fluid (intracellular fluid), known as cytosol. Apart from the organelles, this fluid contains substances such as proteins, other nutrient molecules, metabolic products and also a range of chemicals known as electrolytes. Outside the cells, there is the extracellular fluid, which is composed of the interstitial fluid and the circulating fluid; the latter consists of blood in the vascular system and the lymph in the lymphatic vessels. The extracellular fluid has a similar composition to the intracellular fluid. However, there are important differences in the composition of these fluids, particularly in the type and quantity of electrolytes and in the distribution of protein molecules, as well as the dissolved gases. The intracellular and extracellular environments are separated by the cell membrane, which is selectively permeable; it is able to control the movement of electrolytes and other molecules across it. This characteristic will be discussed later in the chapter. The correct balance and movement of these chemicals between the intracellular and extracellular environments is vital to the maintenance of normal function and therefore health (Marieb and Hoehn 2019). A disruption of this balance is one of the factors that can cause homoeostatic imbalance and potentially lead to a medical emergency (Kumar and Clarke 2017).
The cell and tissues
Ian Peate, Helen Dutton in Acute Nursing Care, 2014
Before considering the basic structure of the cell it is important to consider the physiological environment of the cell. All human cells contain an aqueous fluid (intra-cellular fluid) identified as cytosol. Apart from the organelles, this fluid contains substances such as protein, other nutrient molecules, metabolic products and also a range of chemicals known as electrolytes. Outside the cells there is the extracellular fluid, which is composed of the interstitial fluid just mentioned and the circulating fluid; this is composed of blood in the vascular system and the lymph found in the lymphatic vessels. The extracellular fluid has a similar composition to the intracellular fluid. However, there are important differences in the composition of these fluids, particularly in the type and quantity of electrolytes and in the distribution of protein molecules.
Influence of Dietary Supplements on Body Composition
Henry C. Lukaski in Body Composition, 2017
At a macro level, the changes in muscle size produce male pattern hypertrophy emphasizing the upper body. Bhasin put to rest the question of whether or not supra-physiological levels of testosterone in normal men could increase muscle mass in healthy young men just as it did in hypogonadal men (Bhasin et al. 2001). Increases in fat-free mass were dose dependent with up to an average of nearly 8 kg gain at the 600 mg/week dose of testosterone enanthate for 20 weeks (Bhasin et al. 2001) (Figure 16.1). Body composition changes were assessed in the same studies using DXA, underwater weighing, and MRI scans of leg muscles. Changes in fat mass are less consistently reported in any studies of androgen administration to healthy men. In previous studies such as one reported by Forbes et al., testosterone treatment causes an apparent lean mass gain and fat mass loss (Forbes et al. 1992) (Figure 16.1). However, these changes are largely temporary, with a return toward the original body composition following drug cessation (Friedl et al. 1990; Forbes et al. 1992). Such observations suggest that the rapid changes may involve intracellular fluid retention. However, in Bhasin’s studies, body water, measured by deuterium dilution, averaged around 74% of the fat free mass, with nonstatistical increases at highest doses of testosterone, suggesting that the weight gains were primarily associated with protein accretion (Bhasin et al. 2001). Circulating IGF-1 levels demonstrate dose-dependent increases with testosterone administration.
Comparative studies on the potential use of 177Lu-based radiopharmaceuticals for the palliative therapy of bone metastases
Published in International Journal of Radiation Biology, 2020
Hesham M. H. Zakaly, Mostafa Y. A. Mostafa, Darya Deryabina, Michael Zhukovsky
In Figure 5, the models for 153Sm-EDTMP and 177Lu-EDTMP are visualized using the data provided in Table 2. However, the values of the excretion coefficients for mice were experimentally obtained for 177Lu-EDTMP (Chakraborty, Das, Sarma, et al. 2008). These data can be used as a first approximation for humans. This technique is quite common when evaluating the effectiveness of drugs before conducting preclinical studies (Chakraborty, Das, Sarma, et al. 2008). Figure 6 shows the biokinetic model of the 177Lu-EDTMP preparation, based on transformed data for the human body. All the liquid in the human body can be divided into intracellular and extracellular types. Extracellular fluid is approximately 33% of total body fluid. Intracellular fluid is the fluid circulating between cells and plasma in the bloodstream (Insel and Turner 2007).
Effect of carbohydrate–electrolyte consumption on insulin, cortisol hormones and blood glucose after high-intensity exercise
Published in Archives of Physiology and Biochemistry, 2019
Ahmet Mor, Yildirim Kayacan, Gokhan Ipekoglu, Erkal Arslanoglu
Electrolytes are the minerals with electrical transmission capacity which become ions in the solution. The electrolyte balance of the body is necessary for the normal functioning of the cells. The changes occurring in the electrolyte balance as a result of dehydration of the body impair the cardiovascular and thermoregulatory functions. The main electrolytes important for exercise performance are sodium, chloride, and potassium. Of these, sodium is the main positive ion in the extracellular fluid and helps to regulate acid–base balance, neurotransmission, blood pressure and muscle function. Whereas potassium is the main cation in the intracellular fluid and helps to preserve the electrical activity of the nerves, skeletal muscles, and heart. In addition to this, potassium aids in carbohydrate metabolism by increasing the transport of glucose and glycogen storage (Ziegenfuss et al. 2015). Previous studies have demonstrated that carbohydrate–electrolyte ingestion after exercise has positive effect on athletes’ which inhibits to cortisol, regulates the glucose concentrations with electrolytes and it increases the insulin levels (Davis and Brown 2001, Haff et al. 2003, Evans et al. 2009).
Efficient simulations of stretch growth axon based on improved HH model
Published in Neurological Research, 2023
Xiao Li, Xianxin Dong, Xikai Tu, Hailong Huang
The distribution of ions inside and outside the membrane in the resting state is depicted in Figure 1. Considering that the cell membrane works as an insulator, the extracellular fluid near the cell membrane is positively charged, while the intracellular fluid near the cell membrane is negatively charged, due to the exudation of a small quantity of potassium ions from the cell membrane. The combination of the positively charged external fluid, the insulating cell membrane, and the negatively charged internal fluid forms a capacitor capable of storing electrical charge, referred to as
Related Knowledge Centers
- Body Fluid
- Body Water
- Extracellular Fluid
- Cell Membrane
- Body
- Fascial Compartment
- Solution
- Suspension
- Cell
- Cytosol