Disease relevance of carbocysteine

• The aim of this study was to define the accuracy of 99mTc-ethyl cysteinate dimer-single photon emission computed tomography (99mTc-ECD-SPECT) in distinguishing transient ischemic attack from completed ischemic stroke at early stages after the onset of symptoms [1].
• METHODS: Sixteen patients with acute stroke were examined consecutively with diffusion-weighted MRI and 99mTc-ethyl cysteinate dimer (99mTc-ECD) SPECT within 24 h of the onset of symptoms [2].
• OBJECTIVE: Technetium-99m ethyl cysteinate dimer (99mTc ECD) single photon emission computed tomography (SPECT) of the brain was used to detect abnormal regional cerebral blood flow (rCBF) in patients with primary Sjögren's syndrome (pSS) and normal findings on brain magnetic resonance imaging (MRI) [3].
• Technetium Tc-99m ethyl cysteinate dimer brain single-photon emission CT in mild traumatic brain injury: a prospective study [4].
• Tc-99m ethylene cysteinate dimer SPECT in the differential diagnosis of parkinsonism [5].

Psychiatry related information on carbocysteine

• We undertook this study to assess the patterns of regional cerebral perfusion (RCP) with SPECT using Technetium- 99m-ethyl cysteinate dimer (Tc-99m-ECD) in children with Tourette's Syndrome (TS), and to compare these with the patterns in a group of normal controls [6].
• Tc-99m ethyl cysteinate dimer SPECT and 2-[F-18]fluoro-2-deoxy-D-glucose PET in Alzheimer's disease. Comparison of perfusion and metabolic patterns [7].
• OBJECTIVE: The authors hypothesized that there is a pattern difference in cerebralperfusion of the 99-Technitium L, L-ethyl cysteinate dimer Single Photon Emission Computer Tomography (99-Tc ECD SPECT) between mild and moderate to severe dementia [8].

High impact information on carbocysteine

• The probable active-site cluster, previously termed the H-cluster, was found to be an unexpected arrangement of six iron atoms existing as a [4Fe-4S] cubane subcluster covalently bridged by a cysteinate thiol to a [2Fe] subcluster [9].
• The results support a catalytic mechanism for SOR, with the first step involving oxidative addition of superoxide to form a ferric-peroxo intermediate, and indicate the important roles that the Fe spin state and the trans cysteinate ligand play in effecting superoxide reduction and peroxide release [10].
• Given the proven fingerprinting capability of MCD spectroscopy, this provides convincing evidence for endogenous thiolate (cysteinate) ligation to the heme iron of NOS [11].
• The aim of this study was to investigate the efficacy of pre- and posttreatment 99mTc-ethyl cysteinate dimer (99mTc-ECD) single photon emission computed tomography (SPECT) for predicting the ischemic outcome of embolic middle cerebral artery occlusion after treatment with local intraarterial thrombolysis [12].
• The usefulness of technetium-99m-labeled cysteinate dimer as a marker in the measurement of regional cerebral blood flow was tested in five cynomolgus monkeys [13].

Biological context of carbocysteine

• Biophysical characterization of this enzyme has led to the assignment of the heme ligands as histidine and cysteinate, respectively, which has recently been confirmed by crystal structure determination of the catalytic core of the protein [14].
• The safety, biodistribution and kinetics of a new perfusion imaging agent [99mTc-L,L]-ethyl cysteinate dimer (ECD) was evaluated in normal volunteers [15].
• Silver cysteinate appeared to have the greatest effect on fecundity, with a no-observable-effect concentration (NOEC) less than 0.001 microg/L [16].
• In order to quantitatively characterize the risk associated with silver in aquatic ecosystems, the bioavailabilities and toxicities of silver cysteinate and silver glutathionate were characterized [16].
• Enzymatic hydrolysis of the pendant ester group of [99mTc](SNS/S) mixed ligand complexes by esterase was investigated in vitro and compared with that of the ethyl cysteinate dimer, [99mTc]ECD [17].

Anatomical context of carbocysteine

• DESIGN: Technetium Tc 99m ethyl cysteinate dimer SPECT study using a Patlak plot.Patients Hiroshima University Hospital, Hiroshima, Japan. Ten patients with SCA6 and 9 healthy controls.Main Outcome Measure The rCBF of the cerebellar vermis, cerebellar hemisphere, and frontal lobes [18].
• Technetium-99m ethyl cysteinate dimer ([99mTc]ECD) is a neutral, lipophilic complex which rapidly crosses the blood-brain barrier [19].
• An attempt was made to use 99Tcm-ethyl cysteinate dimer (99Tcm-ECD) (Neurolite, Du Pont Merck, N. Billerica, MA) to label leukocytes [20].
• Magnetic resonance imaging revealed focal cortical dysplasia mainly in the left parietal lobe, and ictal technetium-99m-ethyl cysteinate dimer SPECT images demonstrated an area of hyperperfusion around the focal cortical dysplasia, including the left precentral gyrus [21].
• Ictal single-photon emission computed tomography using (99m)Tc ethyl cysteinate dimer revealed increased perfusion of the contralateral basal ganglia, which is associated with onset of choreoathetosis attacks [22].

Associations of carbocysteine with other chemical compounds

• In one-electron-reduced analogues, cleavage of the active-site disulfide is accompanied by coordination of one of the cysteine residues that form the active-site disulfide to yield a [Fe(4)S(4)](3+) cluster with two cysteinate ligands at a unique Fe site [23].
• OBJECTIVE: To investigate the cerebral perfusion patterns of the subcortical structures by using serial technetium Tc 99m-ethyl cysteinate dimer SPECT in a case of SC, which may provide a clue for the pathophysiological mechanisms [24].
• The rate of P420 formation is accelerated at lower pH, consistent with protonation of the cysteinate (Cys 394) to a thiol underlying the P450-P420 transition [25].
• The energy of the porphyrin(pi)-to-Fe(III) charge-transfer band (8930 cm(-)(1)) and the presence of cysteinate S-to-Fe(III) charge-transfer bands between 600 and 700 nm confirm cysteinate axial ligation to the low-spin Fe(III) hemes in oxidized wild-type and H77Y CooA [26].
• Together, these data support assignment of the axial ligands as cysteinate and imidazole in ferric cystathionine beta-synthase [27].

Gene context of carbocysteine

• The results establish that the metal-binding domains bind Cu(I) predominantly in a bis cysteinate environment, and are able to bind exogenous ligands such as DTT in a similar fashion to Atox1 [28].
• We studied the effects of MPH on brain activity in male children and adolescents with ADHD, using the blood flow radiotracer technetium-99m ethyl cysteinate dimer ((99m)Tc-ECD) and single-photon emission tomography (SPET) [29].
• Using L,L-ethyl cysteinate dimer (99mTc ECD) SPECT and SPM, we aimed to clarify the association of rCBF changes with psychiatric symptoms in SLE patients whose magnetic resonance imaging (MRI) showed no morphological abnormalities [30].
• METHODS: Ictal and interictal (99m)Tc-ethyl cysteinate dimer SPECT images were acquired for 6 children with partial epilepsy (age range, 2-10 y) [31].
• METHODS: Brain perfusion SPECT with 99mTc-ethyl cysteinate dimer (99mTc-ECD) was used in 16 right-handed patients with aphasia after a left-sided cerebrovascular accident (CVA) in the early chronic period after the onset of CVA [32].

Analytical, diagnostic and therapeutic context of carbocysteine

• The iron-sulfur distances are consistent with thiolate ligation, presumably from cysteinate, in all four states of the enzyme [33].
• An extensive series of ligand complexes of ferric cytochrome P-450-CAM has been examined by UV-visible absorption, magnetic circular dichroism, and electron paramagnetic resonance spectroscopy in an attempt to identify the ligand trans to cysteinate in the six-coordinate resting state of the enzyme [34].
• Prediction of acute embolic stroke outcome after local intraarterial thrombolysis: value of pretreatment and posttreatment 99mTc-ethyl cysteinate dimer single photon emission computed tomography [12].
• METHODS: Patients were prospectively studied with (99m)Tc-ethyl cysteinate dimer single photon emission computed tomography ((99m)Tc-ECD-SPECT) before treatment with recombinant tissue plasminogen activator (rTPA; 0.9 mg/kg IV; n=26) or placebo (n=26) 6 to 8 hours after treatment and at 7+/-1 days [35].
• Recently, a new SPECT brain perfusion agent, 99mTc-ethyl cysteinate dimer (99mTc-ECD) has emerged with purported advantages in image quality over the established tracer, 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) [36].

References