Precipitates, pathological

Almost anyone who has at some time in his life met some reverses is familiar with depression. In the normal course of events, changing circumstances will soon lead to the replacement of this state of mind by a more pleasant one. There exist, however, a set of pathologic states in which depression feeds on itself in a destructive cycle. Individuals affected with this syndrome— whether precipitated by outside events or not—eventually find it most difficult to function. The advent of antidepressant drugs, first the MAO inhibitors and more recently the tricyclic antidepressants, have made this syndrome amenable to treatment. 

The nitrogen content of this mixture amounted in the case of normal urine to 0.68-1.27% of the total nitrogen, whereas the peptides precipitated under these circumstances constituted 16.1-20.9% of all substances appearing in urine and giving the biuret reaction. The peptide mixtures obtained in identical conditions from six samples of pathological urine (liver cirrhosis and leukemia) exhibited marked differences in the nitrogen and peptide content as compared with those isolated from normal urine. 

The potential sequelae to an immune response (formation of neutralizing antibodies, provoking an autoimmune or a hypersensitivity response), and pathology due to immune precipitation, and so on ... 

Like any other protein, the molecular structure of the prion is subject to conformational flexibility and to various thermal-induced fluctuations between varying conformational states. However, if these fluctuations permit the PrP conformation to be attained, then this abnormal conformer promotes the widespread conversion of PrP to PrP , leading to the precipitous deposition of the abnormal protein throughout the brain (mirrored by the rapid and relentlessly downhill clinical course). This pathological self-propagating shape conversion of a-helical PrP to P-sheet PrP may in principle be initiated by a seed PrP molecule in the neurotoxic conformation. This explains the transmissibility of prion diseases and accounts for how susceptible humans exposed to beef from an animal with mad cow disease develop variant Creutzfeldt-Jakob disease. 

Taking into account the simplicity of obtaining optical patterns of erythrocytes and the abihty to detect the structures of pathological precipitation of substances, which are not characteristic of a normal blood plasma sample, the proposed method has significant diagnostic importance and advantages summarised below ... 

Seasonal changes affect the condition of normal skin and may trigger various cutaneous disorders.28,29 In common dermatitis, a decline in barrier function often parallels the increased severity of clinical symptomatology. All these conditions tend to worsen during the winter season when humidity is low.30,31 Abundant indirect evidence indicates that decreased humidity precipitates these disorders, whereas, in contrast, increased skin hydration appears to ameliorate these conditions. The mechanisms by which alterations in relative humidity might influence cutaneous function and induce cutaneous pathology are poorly understood. 

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