Cyanide carbon monoxide and

The nervous system is vulnerable to attack from several directions. Neurons do not divide, and, therefore, death of a neuron always causes a permanent loss of a cell. The brain has a high demand for oxy gen. Lack of oxygen (hypoxia) rapidly causes brain damage. This manifests itself both on neurons and oligodendroglial cells. Anoxic brain damage may result from acute carbon monoxide, cyanide, and hydrogen sulfide poisonings. Carbon monoxide may also be formed in situ in the metabolism of dichloromethylene. 

Although it is moot whether carbon monoxide, cyanide, and thiocyanate should be included as organic compounds, brief comments on their biodegradation are summarized. 

It is known that secondary PD can be the result of damage to the brain by exogenous trauma or agents. For example Mn produces parkinsonian symptoms in exposed minors. Carbon monoxide, cyanide and carbon disulfide poisoning in industrial settings have ended up in conditions like PD. 

MVH is inhibited by CO, cyanide, arsenite, and sulfide. Carbon monoxide, cyanide, and arsenite react only with the reduced enzyme. Spectral modifications of the heme and other results have indicated that the heme is the site of action of these inhibitors as well as the site at which sulfite, nitrite, and hydroxylamine are reduced. The Michaelis constants of the enzyme for sulfite and NADPH are both about 4r-5 itM. 

Certain compounds inhibit the activity of the respiratory chain by blocking the transfer of electrons at certain points. Rotenone and amytal inhibit electron transfer through Complex I. Antimycin A inhibits at the level of Complex III. Cytochrome oxidase activity is inhibited by carbon monoxide, cyanide and hydrogen sulphide. The prevention of electron transport by cyanide which is very rapidly absorbed is responsible for the high toxicity of this compound. 

The study of the inhibitors of enz3rmes has also contributed to our understanding of how enzymes act. Certain enzyme poisons such as carbon monoxide, cyanide and diethyl dithiocarbamate have been shown to inactivate enz)rmes by virtue of their high affinity for metals. Thus the inhibition of cytochrome oxidase by CO and CN is because these combine with the iron of the haem prosthetic group. Similarly, it is the affinity of dithiocarbamate for copper which makes... 

Reactions of foi-maldehyde AVith simple carbon compounds which are often tieated in inorganic texts M-ill be found in this chapter. These compounds include carbon monoxide, cyanides, and ammonium thiocyanate. 

Other usefiil gas sensors include the potentiometric ammonia (64) or hydrogen cyanide probes (65), and amperometric carbon monoxide (66) and nitrogen dioxide (67) devices. The hydrogen cyanide probe is an example of a modem device that relies on changes in the conductivity of electropolymerized film (polyanihne) in the presence of a given gas. 

HRP C contains two different types of metal center (i.e., iron(III) protoporphyrin IX-heme group and two calcium atoms) that are fundamental for the integrity of the enzyme. The heme group is attached to the enzyme at His 170 by a coordinate bond between the histidine side-chain NE2 atom and the heme iron atom. The second axial coordination site is unoccupied in the resting state of the enzyme but available to hydrogen peroxide during enzyme turnover. Small molecules such as carbon monoxide, cyanide, fluoride, and azide bind to the heme iron atom at this distal site, giving six-coordinated PX complexes. 

DiPalma JR. 1971. Noxious gases and vapors I. Carbon monoxide, cyanides, methemoglobin, and sulfhemoglobin. In Drill s pharmacology in medicine. McGraw-Hill Book Co., New York, NY. pp.l 189-1205. 

Many covalently bonded gases (including carbon monoxide, ammonia, and hydrogen cyanide)... 

Pi bonding between metal and ligands provides a simple raison d etre lor strong field ligands, an issue that crystal field theory could not resolve. If we examine the strong field end of the spectrochemical series (page 405), we find ligands such as nitrite ion, cyanide ion, carbon monoxide, phosphites, and phosphines. The latter two owe their positions in the series to their ability to serve as rt acceptors, as described above, which increases the value of A, relative to what it would be in u [Pg.756]

Low oxidation states are generally stabilized by ligands which have both a donor (lone pairs) and n acceptor (either empty d orbitals or empty antibonding Jt orbitals) capability. Examples of common ligands with these characteristics are carbon monoxide, cyanide ion, alkyl and aryl isocyanides, tertiary phosphines and arsines, and alkyl or aryl phosphites. 

Among them are carbon monoxide, cyanide, benzopyrene, and tar, the same toxic chemicals present in cigarette smoke. (Some researchers feel that any beneficial effects that may be found in the medicinal use of marijuana are actually negated by the current lack of a suitable alternative delivery method.) Additionally, any pesticides sprayed on the plant by the grower are present in the smoke, and are inhaled along with the THC. 

The gaseous phase contains the harmful gases carbon monoxide (CO) and nitrogen oxide, along with carbon dioxide, ammonia, hydrogen cyanide, benzene,... 

Asphyxiates paralyze the respiratory center and weaken the body. They disturb the maintenance of an adequate oxygen supply to different systems in the body. The most common asphyxiates are carbon dioxide, carbon monoxide, cyanides, helium, nitrogen, and nitrous oxide. 

Blood or tissue agents are chemicals that affect the body by being absorbed into and distributed by the blood to the tissues. Substances include arsine, carbon monoxide, cyanide agents, and sodium monofluoroacetate. 

Copper compounds containing carbon-bound ligands, such as cyanide, carbon monoxide, alkyls, and so on are covered elsewhere (see Copper Organometallic Chemistry). 

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