Neurologic Manifestations of Organic Chemicals

2017 ◽  
Author(s):  
John L. O’Donoghue
Keyword(s):  
Nervous System ◽  
Underlying Mechanism ◽  
Clinical Situation ◽  
Organic Chemical ◽  
Organic Chemicals ◽  
Neurologic Manifestations ◽  
Specific Chemical ◽  
Functional Changes ◽  
Naturally Occurring ◽  
Pathological Appearance

Organic chemicals can produce many different effects on the nervous system. The nervous system functions are affected by a variety of different organic chemicals. Organic chemicals that induce neurotoxicity may be naturally occurring or synthetic. Those that are naturally occurring products of plants or animals are referred to as “toxins,” whereas those that are synthetic are referred to as “toxicants”; however, publications and regulations sometimes use these terms interchangeably. Underlying these functional changes are cellular and subcellular changes that mediate the clinical and pathological appearance of the neurotoxicity. The ability to make a diagnosis of organic-chemical-induced neurotoxicity is dependent on being able to link a clinical situation with an exposure in a dose-related manner. Treatment and management of organic-chemical-induced neurotoxicity in affected individuals is dependent upon the specific chemical involved and the underlying mechanism by which toxicity occurs.

Effects of Copper Extraction-Stripping Loops on Entrainment in Aqueous Raffinate

2014 ◽  
Vol 908 ◽  
pp. 18-21
Author(s):  
Yan Jun Liu ◽  
Xiao Rong Liu ◽  
Hui Li ◽  
Yong Sheng Li ◽  
Qing Li ◽  
...  
Keyword(s):  
Surface Tension ◽  
Solvent Extraction ◽  
Early Stage ◽  
Organic Chemical ◽  
Copper Extraction ◽  
Organic Chemicals ◽  
Stabilization Mechanism ◽  
Absolute Value ◽  
Copper Solvent Extraction ◽  
Average Size

Effects of extraction-stripping loops of organic phase on organic chemical entrainment in the aqueous raffinate in copper solvent extraction were studied in this paper. Results demonstrated that the total amount of organic chemicals lost in the aqueous raffinate decreased with the increase of times of extraction-stripping loops but reached largest at third loop. Entrainment was the dominate way of organic chemicals losing in the aqueous raffinate at early stage of the loops. The formation of entrainment and its stabilization mechanism was also studied. The average size of entrained droplet trended to increase with extraction-stripping loops increasing. Meanwhile, the absolute value of zeta potential trended to decrease. The surface tension of the aqueous raffinate increased after reaching the minimum value 41.3 mN/m at the 3rd loop. It showed that the formation of entrained droplets and its stability were mainly affected by the surface tension of aqueous raffinate.

scholarly journals Dopamine Transporter Genetic Reduction Induces Morpho-Functional Changes in the Enteric Nervous System

Biomedicines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 465
Author(s):  
Silvia Cerantola ◽  
Valentina Caputi ◽  
Gabriella Contarini ◽  
Maddalena Mereu ◽  
Antonella Bertazzo ◽  
...  
Keyword(s):  
Nervous System ◽  
Small Intestine ◽  
Enteric Nervous System ◽  
Dopamine Transporter ◽  
Myenteric Plexus ◽  
Receptor Activation ◽  
D1 Receptor ◽  
Functional Changes ◽  
Neurochemical Coding ◽  
The Impact

Antidopaminergic gastrointestinal prokinetics are indeed commonly used to treat gastrointestinal motility disorders, although the precise role of dopaminergic transmission in the gut is still unclear. Since dopamine transporter (DAT) is involved in several brain disorders by modulating extracellular dopamine in the central nervous system, this study evaluated the impact of DAT genetic reduction on the morpho-functional integrity of mouse small intestine enteric nervous system (ENS). In DAT heterozygous (DAT+/−) and wild-type (DAT+/+) mice (14 ± 2 weeks) alterations in small intestinal contractility were evaluated by isometrical assessment of neuromuscular responses to receptor and non-receptor-mediated stimuli. Changes in ENS integrity were studied by real-time PCR and confocal immunofluorescence microscopy in longitudinal muscle-myenteric plexus whole-mount preparations (). DAT genetic reduction resulted in a significant increase in dopamine-mediated effects, primarily via D1 receptor activation, as well as in reduced cholinergic response, sustained by tachykininergic and glutamatergic neurotransmission via NMDA receptors. These functional anomalies were associated to architectural changes in the neurochemical coding and S100β immunoreactivity in small intestine myenteric plexus. Our study provides evidence that genetic-driven DAT defective activity determines anomalies in ENS architecture and neurochemical coding together with ileal dysmotility, highlighting the involvement of dopaminergic system in gut disorders, often associated to neurological conditions.

Chronic rejection causes early destruction of the intrinsic nervous system in rat intestinal transplants

1997 ◽  
Vol 273 (2) ◽  
pp. G413-G421 ◽  
Author(s):  
P. F. Heeckt ◽  
W. Halfter ◽  
W. H. Schraut ◽  
A. J. Bauer
Keyword(s):  
Nervous System ◽  
Chronic Rejection ◽  
Circular Muscle ◽  
Electrical Field Stimulation ◽  
Functional Changes ◽  
Diaphorase Activity ◽  
Enteric Nerves ◽  
Mucosal Changes ◽  
Oxide Synthase ◽  
Muscularis Externa

Chronic rejection is the major cause of late intestinal allograft dysfunction. We have previously shown that chronic rejection alters the muscularis externa of the graft. This study determined structural and functional changes to the enteric nerves during chronic rejection. Chronic rejection was achieved in orthotopic intestinal transplants (ACI to Lewis) by limited immunosuppression. Syngeneic transplants (ACI to ACI) and unoperated ACI rats served as controls. Animals were clinically healthy and showed no significant alterations in the mucosal architecture on postoperative day 90. Staining for NADPH diaphorase activity (nitric oxide synthase-containing neurons) and with neurofilament antibody RT-97 revealed that chronic rejection decreased the number of jejunal myenteric ganglia by approximately 50%. Inhibitory junction potentials (IJPs) to circular muscle cells were determined by electrical field stimulation (EFS). In controls and syngeneic grafts, EFS caused a stimulus-dependent increase in IJP amplitude, with a maximal amplitude of 9 +/- 0.4 and 10 +/- 0.8 mV, respectively. Chronic rejection in allografts markedly increased the threshold for IJP initiation and decreased the maximal IJP amplitude (5 +/- 0.8 mV). Our data indicate that chronic rejection severely damages the muscularis and the enteric nervous system before mucosal changes become evident.

“CHANGES IN THE NERVOUS SYSTEM IN PATIENTS WITH DIABETES MELLITUS TYPE 2 WITH NEPHROPATHY AND PROGNOSTIC SIGNIFICANCE OF NEUROMARKERS OF BRAIN INJURY. LITERATURE REVIEW"

2021 ◽  
pp. 3-8
Author(s):  
Yu. Urmanova ◽  
A. Holikov
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Nervous System ◽  
Type 2 Diabetes Mellitus ◽  
Biochemical Markers ◽  
Prognostic Significance ◽  
Functional Changes ◽  
Neurospecific Proteins

THE PURPOSE OF THE STUDY is to carry out an analysis of the literature evaluating diabetic encephalopathy by determining neuromarkers. MATERIAL AND METHODS. In this article, the authors analyzed the literature on the role of neuromarkers in patients with type 2 diabetes mellitus undergoing program hemodialysis. RESEARCH RESULTS. Among biochemical markers, the determination of the level of neurospecific proteins is actively being investigated. The main part of them is autoantigens, entering the bloodstream, can cause the appearance of autoantibodies, which, when the blood-brain barrier is impaired, enter the brain from the blood vessel and cause morphological changes, destructive processes in neurons, as well as the development of nonspecific acute-phase reactions like edema or inflammation. Biomarker studies for the diagnosis of various brain lesions have been under way for more than 20 years, but at present no ideal biomarker has been found. Among biochemical markers, the determination of the level of neurospecific proteins is being actively studied. In patients with type 2 diabetes mellitus undergoing hemodialysis, this issue is also relevant in view of the frequent vascular cerebrovascular complications, but few studies have been conducted. CONCLUSIONS. All of the above emphasizes the need to identify the features of clinical and functional changes in the nervous system in patients with type 2 diabetes mellitus receiving program hemodialysis and to evaluate the prognostic value of neuromarkers in early detection of the degree of brain damage. 

Peroxide Pre-Oxidation of Recalcitrant Toxic Waste to Enhance Biodegradation

1991 ◽  
Vol 23 (1-3) ◽  
pp. 367-376 ◽  
Author(s):  
J. B. Carberry ◽  
T. M. Benzing
Keyword(s):  
Hydrogen Peroxide ◽  
Toxic Waste ◽  
Organic Chemical ◽  
Organic Chemicals ◽  
Aqueous Systems ◽  
Industrial Chemicals ◽  
Soil Systems ◽  
Oxidation Technology ◽  
Land Disposal ◽  
Pre Treatment

Land disposal is required for industrial chemicals which are not readily biodegraded. Such compounds lead to adverse effects on the environment if they escape containment. Recalcitrant and persistent hydrocarbons and chlorinated chemicals are inherently resistant to any degree of biodegradation and cause a growing threat to underground aquifer quality. Hydrogen peroxide is a potentially economical method of pre-oxidation utilized to enhance the biodegradation of persistent and recalcitrant organics in contaminated soil systems. This pre-oxidation technology was examined in a laboratory respirometer using three model toxic organic chemicals: toluene, trichloroethylene and pentachlorophenol. Microbial cultures were selected from contaminated sites for the degradation of each model organic chemical. The rate at which the microbes degraded the organic chemicals in unoxidized aqueous systems was compared to the rate of degradation in peroxide pre-oxidized aqueous systems. Results indicated that pre-oxidation enhanced the biodegradation of trichloroethylene and pentachlorophenol. Toluene, in contrast, was not significantly oxidized by pretreatment with hydrogen peroxide, and its biodegradation rate was not enhanced by the oxidation pre-treatment process.

scholarly journals Research on the Neurobiology of COVID-19

2021 ◽  
Vol 245 ◽  
pp. 03045
Author(s):  
Yilun Tong
Keyword(s):  
Nervous System ◽  
Molecular Mechanism ◽  
The Novel ◽  
Neurologic Manifestations ◽  
Neurological Manifestations ◽  
Corona Virus ◽  
The World ◽  
Human Nervous System ◽  
Different Parts

More studies have shown the neurological manifestations of the novel corona virus (COVID-19) and have inferred the molecular mechanism by which it invades the nervous system. The neurological aspect of the COVID-19 pandemic has been differently interpreted and dealt with in different parts of the world. To review the neurological manifestations and the neurovirulent mechanism by which CoV attacks the human nervous system and to examine different perspectives on this very same topic, the research on PubMed and ScienceDirect is conducted. The mechanisms that CoV enter and attack the nervous system and the subsequent neurologic manifestations have been proposed and now seems quite clear. However, more studies have to be done directly on the effect of COVID-19 on the CNS as well as the PNS.

scholarly journals Activation of central 5-HT2A receptor in brain inhibited the seizure-induced respiratory arrest in the DBA/1 mouse SUDEP model

2020 ◽  
Author(s):  
Yue Shen ◽  
HaiXiang Ma ◽  
XiTing Lian ◽  
LeYuan Gu ◽  
Qian Yu ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Drug Resistance ◽  
Nervous System ◽  
Underlying Mechanism ◽  
Respiratory Arrest ◽  
Acoustic Stimulation ◽  
Unexpected Death ◽  
Anti Epileptic Drug ◽  
The Brain

AbstractSudden unexpected death in epilepsy (SUDEP) is the fatal cause leading to the death of epilepsy patients with anti-epileptic drug resistance. However, the underlying mechanism of SUDEP remains to be elusive. Our previous study demonstrated that enhancement of serotonin (5-HT) synthesis by intraperitoneal (IP) injection of 5-hydroxytryptophan in brain significantly reduced the incidence of seizure-induced respiratory arrest (S-IRA) in DBA/1 mice SUDEP models. Given that 5-HT2A receptor (5-HT2AR) acts an important role in mediating respiration system in brain, we hypothesized that 5-HT2AR is of great significance to modulate S-IRA and SUDEP. To test this hypothesis, we examined whether the decreased incidence S-IRA evoked by either acoustic stimulation or PTZ by blocking 5-HT2AR by administration with ketanserin (KET), a selective antagonist of 5HT2AR, in DBA/1 mice SUDEP models to test the role of 5-HT2AR modulating S-IRA. Our results suggested that the decreased incidence of S-IRA by 5-Hydroxytryptophan (5-HTP), a precursor for central nervous system (CNS) serotonin (5-HT) synthesis, was significantly reversed by IP and intracerebroventricularly (ICV) injection of ketanserin in our models. Thus, our data suggested that 5-HT2AR in the brain may be a potential and specific target to prevent SUDEP.

Effects of the Non-protein Amino Acids L-Canavanine and L-Canaline on the Nervous System of the Moth Manduca Sexta (L.)

1978 ◽  
Vol 75 (1) ◽  
pp. 123-132
Author(s):  
ANN E. KAMMER ◽  
D. L. DAHLMAN ◽  
GERALD A. ROSENTHAL
Keyword(s):  
Nervous System ◽  
Manduca Sexta ◽  
Biologically Active ◽  
Muscle Fibres ◽  
Time Interval ◽  
Hydrolytic Cleavage ◽  
Fresh Weight ◽  
Naturally Occurring ◽  
The Central Nervous System ◽  
Protein Amino Acids

Injection of L-canavanine, a naturally occurring arginine analogue, and of its metabolic derivative, L-canaline, induced almost continuous motor activity in adult tobacco hornworms, Manduca sexta (L.). Initially the moths flew normally, but after a time interval that depended both on the amino acid and on the dose (1-l45/μmol/g fresh weight) the moths became disorientated and muscle activity was less patterned. Canaline produced its initial effects 12-30 min after injection, whereas activity in response to canavanine began after a delay of 1-2 h. Canaline (derived from canavanine by an arginase-mediated hydrolytic cleavage) is probably the biologically active factor. Canaline did not affect axonal conduction of action potentials nor the activity of mechanoreceptors on the forewing. Canaline (22μmol/g fresh weight) prolonged the postsynaptic potential of flight muscle fibres, but after 20-40 min. the electrical activity of muscle fibres was normal. The results show that canaline alters the activity of the central nervous system of adult M. sexta, but its mode of action is unknown.

Examining the nervous system of an older patient

2017 ◽  
pp. 865-870
Author(s):  
Henry J. Woodford ◽  
James George
Keyword(s):  
Nervous System ◽  
White Matter Lesions ◽  
Clinical Situation ◽  
Neurological Assessment ◽  
Risk Of Death ◽  
Age Related ◽  
Power Testing ◽  
The Individual ◽  
The Brain ◽  
Age Related Changes

Ageing is associated with changes in the nervous system, especially the accumulation of neurodegenerative and white matter lesions within the brain. Abnormalities are commonly found when examining older people and some of these are associated with functional impairment and a higher risk of death. In order to reliably interpret examination findings it is important to assess cognition, hearing, vision, and speech first. Clarity of instruction is key. Interpretation of findings must take into account common age-related changes. For example, genuine increased tone should be distinguished from paratonia. Power testing should look for asymmetry within the individual, rather than compare to the strength of the examiner. Parkinsonism should be looked for and gait should be observed. Neurological assessment can incorporate a range of cortical abilities and tests of autonomic function, but the extent of these assessments is likely to be determined by the clinical situation and time available.

Serial cranial computed-tomography scans in children with leukemia given two different forms of central nervous system therapy.

1983 ◽  
Vol 1 (12) ◽  
pp. 793-798 ◽  
Author(s):  
J J Ochs ◽  
L S Parvey ◽  
J N Whitaker ◽  
W P Bowman ◽  
L Ch'ien ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Central Nervous System ◽  
Nervous System ◽  
Ct Scan ◽  
Lymphoblastic Leukemia ◽  
Clinical Situation ◽  
Cranial Irradiation ◽  
Cranial Computed Tomography ◽  
Intrathecal Methotrexate ◽  
Central Nervous System Toxicity

Cranial computed tomography (CT) was used to estimate the frequency and permanence of brain abnormalities in 108 consecutive children with acute lymphoblastic leukemia (ALL). Fifty-five patients received cranial irradiation (1,800 rad) with intrathecal methotrexate (RT group) and 53 patients received intravenous and intrathecal methotrexate without irradiation (IVIT group). Continuation treatment included sequential drug pairs for the RT group and periodic IVIT methotrexate for the other group. After 12 to 24 months of serial evaluation, five (9%) of the 55 patients in the RT group have had CT scan abnormalities, compared to 10 (19%) of 52 in the IVIT group (p = 0.171). Fourteen of the 15 patients with CT scan abnormalities had focal or diffuse white-matter hypodensity; these have reverted to normal in most cases, reflecting a dynamic process. While such CT findings are of concern and may be an early indicator of central nervous system toxicity, this remains to be proven. Therapy should not be altered on the basis of abnormal CT scans alone but in the context of the entire clinical situation.

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