China
Africa
Explore chapters and articles related to this topic
Gene Therapy and Gene Correction
Published in Yashwant V. Pathak, Gene Delivery Systems, 2022
Manish P. Patel, Sagar A. Popat, Jayvadan K. Patel
Crigler-Najjar syndrome: This is a genetic disorder affecting the breakdown of bilirubin. Due to excessive amounts of bilirubin, neonatal jaundice occurs. There is a high level of unconjugated bilirubin in the brain, which leads to brain damage in infants. This disease is caused by a mutation or deficiency in the UDP glucuronosyltransferase 1 family, specifically the polypeptide A1 (UGT1A) gene that encodes UDP-glucuronosyltransferase 1 (UGT) enzymes (Jansen 1999). These enzymes are important for the metabolism and excretion of bilirubin. Deficiency of these enzymes causes higher amounts of bilirubin, which as mentioned, causes jaundice. By using various vectors like an adenoviral vector, AAV vector, lentiviral and naked plasmid DNA approaches, a corrected gene is inserted in the mutated liver, and results show that it corrects the excessive amount of bilirubin which is present in the rat model for Crigler-Najjar syndrome (Jia et al. 2005; Seppen et al. 2006; Van Der Wegen et al. 2006).
Light Sources
Published in Toru Yoshizawa, Handbook of Optical Metrology, 2015
Treatment of neonatal jaundice is another original medical application of high-brightness LEDs developed by Okamoto et al. [134]. Neonatal jaundice is caused by the surplus of bilirubin in the bloodstream, which exists in the blood serum. Bilirubin is most sensitive to blue light with wavelength 420–450 nm. Under blue (420–450 nm) and green (500–510) lights, the original bilirubin is transformed from oleaginous bilirubin to water-soluble bilirubin, which is easier to excrete by the liver and kidneys. The conventional method of phototherapy for hyperbilirubinemia utilizes bluish-white or bluish-green fluorescent lamps; few fluorescent lamps are placed 40–50 cm above the newborn laid in an incubator. The LED phototherapy apparatus of Okamoto uses Nichia blue (450 nm) and bluish-green (510 nm) InGaN LEDs. Seidman et al. [135] performed clinical investigation of the LED therapeutic effect on 69 newborns, which showed that LED phototherapy is as efficient as conventional phototherapy, but the LED source has the advantages of being smaller, lighter, and safer (no glass parts, no UV radiation), in addition to low DC voltage supply, long lifetime, and durability. Another advantage of the LED source is the easy control of the LED light output by the driving current to correspond to the necessary treatment.
Extracorporeal devices
Published in Ronald L. Fournier, Basic Transport Phenomena in Biomedical Engineering, 2017
An alternative approach to the treatment of neonatal jaundice is the use of a bilirubin-specific enzyme for the removal of bilirubin from the infant’s blood (Lavin et al., 1985; Sung et al., 1986). The enzyme bilirubin oxidase catalyzes the oxidation of bilirubin according to the following reaction stoichiometry: Bilirubin+12O2→Biliverdin+H2O Calculations indicate that the amount of oxygen needed to convert all of the bilirubin found in the blood is about 100 times less than the actual oxygen content of blood. Therefore, no external supply of oxygen is needed within the enzyme reactor to carry out this reaction. Biliverdin itself is much less toxic than bilirubin and in fact is further oxidized by bilirubin oxidase to other less toxic substances. Experiments using a water-jacketed reactor (much like that in Figure 9.3a) containing bilirubin oxidase covalently attached to agarose beads showed that plasma bilirubin levels in rats decreased by 50% after 30 min of treatment. The rat’s blood was recirculated through the 6 mL reactor volume at a flow rate of 1 mL min−1. Clearly, these results indicate that an immobilized bilirubin oxidase reactor could be an approach for the treatment of neonatal jaundice. It also shows the feasibility of using immobilized enzyme reactors for the specific removal of a harmful substance present in the blood.
Non-invasive and non-contact automatic jaundice detection of infants based on random forest
Published in Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization, 2023
Fatema-Tuz-Zohra Khanam, Ali Al-Naji, Asanka G. Perera, Danyi Wang, Javaan Chahl
Jaundice or hyperbilirubinemia is defined as the yellow discoloration of the skin and sclera of the eyes due to an excess level of bilirubin (Dzulkifli et al. 2018). Generally, jaundice is noticeable when serum bilirubin level exceeds 2.0 mg/dl in the blood (Puppalwar 2012). Bilirubin is a water-soluble tetrapyrrolic yellowish pigment that is present in the blood and whose excess accumulation in the skin results in neonatal jaundice symptoms (Ansong-Assoku and Ankola 2018). Bilirubin is created due to the breakdown of old red blood cells. In the human body, new red blood cells are produced, and old ones are broken down continuously. In an adult, the red blood cells survive for about 120 days; however, in a newborn infant, they survive for a significantly shorter time. Hence, newborns have higher than average quantities of red blood cells, which leads to excess bilirubin level due to the breakdown of more red blood cells (Ansong-Assoku and Ankola 2018). Normally, the damaged blood cells that produce bilirubin are metabolised by the liver for excretion. Later, bilirubin is secreted through urine and bile (Chee et al. 2018). Short-term excess of bilirubin is mostly harmless and self-limiting. But a high level of bilirubin in newborn infants is neurotoxic and can permanently damage the brain, which is called kernicterus. It may cause cerebral palsy, deafness or hearing loss, language difficulties, and developmental delay or can be fatal in the worst cases (Ullah et al. 2016; Chee et al. 2018).