Brain lesion/lesioning

There are certain weU-estabUshed facts about olfaction (6). AU normal people can smell. People suffering from brain lesions, injured olfactory nerve, or obstmcted nasal passages may be anosmic. Cases of preferential anosmia, ie, abUity to sense certain smells and not others, are not weU estabUshed. Such cases occur, but Utde is known of them. 

The demonstration that injected or force-fed neonatal rodents given extremely high doses of MSG showed evidence of brain lesions, has led to much additional research to determine any possible link between neurotoxicity and human use of MSG (33). However, no evidence from animal tests indicates that MSG in the diet causes brain damage in humans (34). 

Seitz RJ, Meisel S, Moll M, Wittsack JH, Junghans U, Seibler M. The effect of combined thrombolysis with rtPA and tirofiban on ischemic brain lesions. Neurology 2004 62 2110-2112. 

Collier, B and Mitchell, JF (1967) Release of ACh during consciousness and after brain lesions. J. Physiol. 188 83-98. 

Dissemination in space by MRI evidence of nine or more T2-weighted brain lesions, or two or more cord lesions, or four to eight brain and one cord lesion, or positive visual evoked potentials with four to eight MRI lesions, or positive visual evoked potentials with less than four brain lesions plus one cord lesion. 

Silent" brain lesions on magnetic resonance imaging are associated with poor cognitive and fine motor functions pseudotumor cerebri (case report)... 

Radiation is an important modality in the treatment of symptomatic metastatic disease. The most common indication for treatment with radiation therapy is painful bone metastases or other localized sites of disease refractory to systemic therapy. Radiation therapy gives significant pain relief to approximately 90% of patients who are treated for painful bone metastases. Radiation is also an important modality in the palliative treatment of metastatic brain lesions and spinal cord lesions, which respond poorly to systemic therapy, as well as eye or orbit lesions and other sites where significant accumulation of tumor cells occurs. Skin and/or lymph node metastases confined to the chest wall area also may be treated with radiation therapy for palliation (e.g., open wounds or painful lesions). 

Surgery followed by whole-brain radiotherapy (WBRT) is best indicated for patients with an accessible single brain lesion and controlled or limited systemic MM.62 Two randomized studies reported improved survival in patients treated with combination surgery and WBRT compared with WBRT alone.62,63 For those patients with multiple metastatic brain... 

Other causes of brain lesions, including hemorrhage, infection, and infarction, should be ruled out. 

The function of the ALD protein is not fully understood, and knockout mice lacking it do not exhibit the severe CNS neurological deficits commonly associated with the human disease despite a similar accumulation of VLCFAs [26], Furthermore, the clinical variability in human patients cannot be accounted for by the severity of the biochemical abnormality or the nature of the gene defect. These observations, plus other data from mice with defects in VLCFA metabolism, raise the issue of whether the accumulation of VLCFAs in myelin is crucial to the pathological mechanisms or is an epiphenomenon. Unlike most other lipid-storage diseases, active ALD brain lesions are characterized by perivascular accumulation of lymphocytes. For this reason, it has been hypothesized that the severity of CNS pathology may relate to an autoimmune reaction that varies from patient to patient and... 

Heinz, G.H. and L.N. Locke. 1976. Brain lesions in mallard ducklings from parents fed methylmercury. Avian Dis. 20 9-17. 

NIOSH (1976) reviewed and summarized animal studies prior to 1976. Many of those studies are deficient in descriptions of exposure and analytical techniques as well as exposure concentrations and durations. Considerations of most of those pre-1976 studies are not reviewed here. Several of those earlier studies describe brain lesions in exposed animals. Histopathological examinations were performed in only a few of the studies conducted after 1976. 

Stahl N, Mellergard P, Hallstrom A, Ungerstedt U, Nordstrom CH. 2001a. Intracerebral microdialysis and bedside biochemical analysis in patients with fatal traumatic brain lesions. Acta Anaesthesiol Scand 45(8) 977-985. 

Before this topic is left behind, it should be noted that statistical significance is by no means the only consideration in interpretation of toxicity test results. If, in our particular case, the pathologist were to inform us that the brain lesion observed was extremely unusual or rare, we should certainly hesitate to dismiss our concerns because of lack of statistical significance. The toxicologist needs equally to understand biological significance, and, in this case, would almost certainly pursue other lines of investigation (perhaps an ADME study to determine if the pesticide reaches the brain, or a toxicity test in other species) to determine whether the effect was truly caused by the chemical. 

Brain imaging (preferably MRI) to look for evidence of structural damage is essential after TBI. MRI, while more expensive and time-consuming, can sometimes detect small brain lesions that are missed by CT, especially in the frontal and temporal lobes that are common sources of psychiatric complications after TBI. In addition, an electroencephalogram (EEG) can detect seizure activity or other signs of abnormal brain function. Although they are not yet part of the routine post-TBI evaluation, the so-called functional brain imaging techniques such as positron emis-... 

MRI is an example of the technological development that is no longer restricted to the crude location of a brain lesion. The recently introduced analytical approach enables the size of the image structures in the MRI to be... 

Multiple sclerosis (MS) is a devastating disease of the CNS that produces demyelination and inflammation. It is believed that its pathogenesis involves an immune reaction against various components of the myelin sheath. In a study by Lock et al. (2002), the gene expression patterns of brain lesions obtained during autopsies of MS patients were examined by microarray cluster analysis. A total of 1080 genes (from 7026 represented... 

Mice exposed continuously to 100 ppm or intermittently to 400 ppm for 11 days had histopathologic evidence of brain lesions characterized by degeneration and atrophy of the granular layer of the cerebellum. Daily exposure of mice to 1000 ppm for 2 years induced a functional limb muscle impairment and atrophy of the spleen. At 2400ppm administered daily, there were renal and hematopoietic effects and the mice were moribund by day 9. For rats exposed to 3 500 ppm 6 hours/day for up to 12 days, clinical signs included severe diarrhea, incoordination of the forelimbs, and, in a few animals, hind limb paralysis and convulsions. ... 

Clonazepam is used in somnambulic epilepsy, various forms of muscular tonus, insomnia (especially in patients with structural brain lesions), and psychomotor agitation. Synonyms of this drag are clonopin and rivotril. 

Seizures Seizures and other CNS adverse experiences have been reported during treatment with meropenem. These adverse experiences have occurred most commonly in patients with CNS disorders (eg, brain lesions or history of seizures) or with bacterial meningitis or compromised renal function. 

Izquierdo I, Medina JH (1998) On brain lesions, the milkman and Sigmunda. Trends Neurosci 21 423-426... 

Wahl F, Renou E, Mary V, Stutzmann JM (1997) Riluzole reduces brain lesions and improves neurological fimction in rats after a traumatic brain injury. Brain Res 756 247-255 WaUstrom E, Diener P, Ljungdahl A, et al (1996) Memantine abrogates nemological deficits, but not CNS inflammation, in lewis rat experimental autoimmime encephalomyelitis. J Neurol Sci 137 89-96... 

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