Structure
The CCDC138 gene encodes a protein that contains multiple alpha helixes, beta sheets and coiled-coils. This protein does not have a transmembrane domain.
Recent structures of activin class cytokine receptors have provided foundational knowledge about how they bind different ligands and elicit a range of cellular responses. These structural studies also enabled comparisons between mutated and wild-type receptors to understand how specific mutations alter the kinase activity of each receptor.
The structure of a hemoglobin 138 variant with decreased oxygen affinity, Hb Brockton [beta 138 (H16) Ala----Pro], revealed that substitution of proline for asparagine at position 138 disrupts critical inter and intrasubunit hydrogen bonds that contribute to the cooperative oxygenation mechanism of normal hemoglobin. Hemoglobin variants with similar oxygen affinity, such as Hb Stanmore [beta 111 (G13) Val----Ala], have not been studied to determine the extent of the disruption of these polar interactions. However, both hemoglobin variants show low intrinsic oxygen affinity. Consequently, their clinical consequences are likely similar to that of Hb Brockton.
Function
The incomplete beta function is a polynomial of degree a + b - 1 with rational coefficients. It has a number of applications in physics, functional analysis and integral calculus. It is related to the gamma function and its generalization, the digamma function.
It can be derived from the Pochhammer contour integral. It can also be derived from the natural logarithm of the inverse function, using a continued fraction expansion. It has been studied by Leonhard Euler and Adrien-Marie Legendre.
It is an important feature of the integrable systems, such as the Yang–Mills theory. It relates the coupling parameter of a quantum field theory to its asymptotic freedom, which is the limit at which one can use perturbation theory. It is the reason why QED becomes strongly coupled at high energy scales and does not obey classical scale invariance. It also dictates that the classical coupling should have a finite value, which gives rise to a Landau pole in the Feynman graphs.
Anemia
A lack of healthy red blood cells (anemia) decreases the amount of oxygen your body can carry. You might have trouble breathing, feel weak and tired, or find it hard to concentrate.
Hemoglobin is a protein inside the red blood cells that carries oxygen to your tissues. When you have too few healthy red blood cells or not enough hemoglobin, you can't get enough oxygen to your organs.
Anemia from a nutritional cause, such as iron deficiency or deficiencies in folate or vitamin B12 can be treated with diet changes and oral or IV supplements of these nutrients. A medicine called folic acid can prevent the absorption of excess iron.
If the anemia is due to blood loss, you might need IV fluids or a transfusion of donated blood. You might also need a medication that helps your body make more red blood cells, such as hydroxyurea (Droxia, Hydrea) or l-glutamine oral powder. If you have sickle cell anemia, treatment includes painkillers, folic acid supplements, and medications that help your red blood cells stay flexible and avoid breaking apart and blocking blood vessels.
Treatment
Despite the loss of oxygen affinity, hemoglobin beta 138 exhibits good electrophoretic mobility and cannot be distinguished from Hb A. X-ray crystallographic data suggest that the substitution of proline for asparagine at beta 138 does not disrupt critical inter and intrachain hydrogen bonds or salt bridges near the oxygen binding site. Consequently, the variant is functionally normal. Patients with this mutation can present with slate-gray cyanosis with no apparent cardiopulmonary disease, falsely low pulse oximetry readings and autooxidation/methemoglobinemia.
In an Alzheimer’s disease (AD) study, avagacestat reduced the levels of A beta 140 and other A beta peptides by inhibiting the activity of -secretase. This drug is being investigated for its potential to slow the progression of AD.
