China
Africa
Explore chapters and articles related to this topic
Inborn Errors of Metabolism
Published in Praveen S. Goday, Cassandra L. S. Walia, Pediatric Nutrition for Dietitians, 2022
Surekha Pendyal, Areeg Hassan El-Gharbawy
The pathophysiology of IEMs can be a result of one or more of the following: The accumulation to toxic levels of substrates prior to the enzymatic blockThe accumulation of toxic intermediates from alternative metabolic pathways in the biochemical reactionDefects in energy productionDeficiency of the products
Pathological Processes of the Eye Related to Chemical Exposure
Published in David W. Hobson, Dermal and Ocular Toxicology, 2020
There are some chemicals that do not seem to have an immediate effect on the eye, but with either continuous exposure to vapors for several hours, or in some cases, several hours after a discrete exposure, they will produce damage to the cornea and adnexa. This group of chemicals are usually cytotoxic to a particular type of cell in the affected tissue as a result of a biochemical reaction. These chemicals produce edema, hyperemia, petechiation, and varicose distortions of the blood vessels in the conjunctiva, as well as epithelial erosion; swelling of the epithelium, stroma, and endothelium of the cornea; and wrinkling of the posterior surface of the cornea. The severe lesions produced by these chemicals often progress to infiltration of inflammatory cells, invasion by interstitial vessels, fibrosis, and finally, permanent scarring, vascularization, and opacity of the cornea. Such extreme reactions are usually rare, but they may be produced by chemicals such as dimethyl sulfate and mustard gas.6
Diseases of the Nervous System
Published in George Feuer, Felix A. de la Iglesia, Molecular Biochemistry of Human Disease, 2020
George Feuer, Felix A. de la Iglesia
The signs of disorder in neurological functions also show variations according to the anatomic level of the nervous system involved. The organization of the basic structural unit, the neuron, and the basic functional unit, the reflex, both become increasingly complex from the peripheral nerve to the spinal cord up the brainstem, diencephalon, and, finally, to the cerebral hemispheres. The consequence of a structural damage or failure of a biochemical reaction is fairly uniform and can be predicted at low anatomic levels. However, as increasing numbers of structural systems, reflexes, and biochemical processes are involved, the result of a lesion at these highest levels shows a great degree of variation and is less predictable.240,298 Many special conditions are known to be related to neurological diseases such as Leigh disease.348,480 Creutzfeld-Jakob disease,571,581 Alzheimer disease,77,161,260,374,461,469,476,502,554,566 Salla disease,27,490 Klinefelter’s syndrome,223,434 Parkinson’s syndrome,89,166,222,622 Wernicke-Korsakoff psychosis,394,395,585 Huntington syndrome,66 Reye syndrome,357 and Hartnup disease.556
Effects of temperature on feeding and digestive processes in fish
Published in Temperature, 2020
Helene Volkoff, Ivar Rønnestad
Since biochemical reaction rates increase with temperature, the standard metabolic rate (SMR, the metabolic rate required to maintain life and routine activity) in the ectothermic fish also increases with temperature (Figure 1(a)). The maximum metabolic rate (MMR or metabolic rate at maximum sustained exercise) on the other hand, usually has a dome-shaped response to temperature, where it increases, and subsequently plateaus or decreases [9]. The metabolic (or aerobic) scope, calculated as the difference between MMR and SMR (plotted in Figure 1(b)), is the surplus energy left after the basal maintenance costs are met and is available for functions such as digestion, locomotion, growth, and reproduction [9,10]. Aerobic scope is used as a proxy for performance (Figure 1(b)).
Polymers, responsiveness and cancer therapy
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Anil M. Pethe, Khushwant S. Yadav
Enzymes are the fundamental proteins which have a significant role to play in most of the vital tasks in a biological molecule. Typically from the smaller chemical reactions in a cell to larger metabolic processes in a tissue or organ comprise of enzymes. It is nearly difficult to imagine a single biochemical reaction inside a human body without the use of enzymes. Enzymes are sharp biological triggers to react over minute changes inside the human body. Sometimes they may be just used as catalyst or to speed up a reaction. The changes in dysregulation of enzyme expression can be very well used for therapeutics. Inherent characteristics of the enzymes like ability to work like a catalyst, specificity, detectability and responsiveness make them important stimuli to work against cancer. For example, as compared to the healthy cells, there is a changed catalyst articulation observed in cancer cells. As cancer-affected cells display features which can be recognized by the enzyme-mediated delivery system. With a proper control over the enzymatic activity, many delivery systems can be used to exploit enzyme responsiveness to target cancer cells. This section describes some of these notable drug delivery systems.
Aluminum oxide nanoparticles mediated toxicity, loss of appendages in progeny of Drosophila melanogaster on chronic exposure
Published in Nanotoxicology, 2019
Avnika Singh Anand, Urmila Gahlot, Dipti N. Prasad, Ekta Kohli
In this study effect of Al2O3 NPs exposure; on behavior, phenotypic changes in subsequent generations and toxicity at the cellular level were studied. We reported for the first-time renal failure, impaired behavior and loss of appendages in progeny flies on chronic exposure of Al2O3 NPs. Proteomics enables us to understand the expression level of a protein on global scale as well as post-translational modifications (Lee et al. 2013). Toxicoproteomics imply qualitative and quantitative proteomics approach in toxicology to study detailed alteration in the global protein expression level of exposure to nanoparticles (Wetmore and Merrick 2004). Toxicoproteomics help us to understand the biochemical reaction in response to toxic chemicals and is an effective tool to develop biomarkers. Expression of specific proteins due to NPs exposure can be systematically analyzed defining the specific term for such studies as ‘nanomaterial toxicoproteomics’ (Nath-Roy et al. 2017). These studies are facilitated by advanced techniques which implies liquid chromatography (LC) and mass spectrometry (MS), the public access to bioinformatics tools and databases, enhances interpretation of data retrieved to attain valuable information (Xie et al. 2011). Thus, we further made an attempt to understand the mechanism of toxicity and correlate the phenotypic and behavioral abnormalities through proteomics approach using LC/MS/MS.