Depression alternative approaches

Although postsynaptic DA agonists and presynaptic Dj autoreceptor antagonists share a common property of enhancing DA transmission, Dj autoreceptor agonists have been developed specifically to block DA transmission as an alternative approach to antipsychotic therapy (Benkert et al. 1992). A variety of such compounds are available (Seyfried and Boettcher 1990), four of which—talipexole, pramipexole, roxindole, and OPC-4392 —have been evaluated as antipsychotics in schizophrenic patients (Benkert et al. 1992). Only roxindole has been tested in depression, and then only in two uncontrolled pilot studies over 4 weeks of treatment (Benkert et al. 1992 M. Kellner et al. 1994). Response rates similar to those of imipramine were observed, with a fast onset of action in some patients. Roxindole s antidepressant action may lie in its ability to selectively stimulate supersensitive postsynaptic Dj receptors, and thereby enhance DA function, or in its additional properties as an inhibitor of serotonin reuptake and as a 5-HT, receptor agonist (Benkert et al. 1992 Seyfried et al. 1989). 

An alternative approach is based on the theoretical foundation described earlier for the colligative properties. If the solution is isotonic with blood, its osmotic pressure, vapor pressure, boiling-point elevation, and freezing-point depression should also be identical to those of blood. Thus, to measure isotonicity, one has to measure the osmotic pressure of the solution and compare it with the known value for blood. However, the accurate measurement of osmotic pressure is difficult and cumbersome. If a solution is separated from blood by a true semipermeable membrane, the resulting pressure due to solvent flow (the head) is accurately measurable, but the solvent flow dilutes the solution, thus not allowing one to know the concentration of the dissolved solute. An alternative is to apply pressure to the solution side of the membrane to prevent osmotic solvent flow. In 1877, Pfeffer used this method to measure osmotic pressure of sugar solutions. With the advances in the technology, sensitive pressure transducers, and synthetic polymer membranes, this method can be improved. However, results of the search for a true semipermeable membrane are still... 

The simple method based on Equation 10.13, however, is not commonly used because 100% pure crystalline samples for most polymers are not available. One alternative approach is to use the fusion enthalpy, the latent heat of melting, of chemical repeated units (A Hu) to replace A/fioo in the calculations. AHu can be calculated using the I dory relationship for the depression of the equilibrium melting temperature of a homopolymer due to the presence of low molecular mass diluents. The AHu values of some polymers are available in literature. 

If there is no receptor reserve for the system, then an insurmountable antagonist, whether allosteric or orthosteric, will produce immediate depression of the agonist concentration-response curve with no concomitant shift to the right. Under these circumstances, no pA2 estimate can be made. In these cases, an alternative approach is to measure the IC50 of the antagonist as it produces antagonism of a given... 

In cases where the plot of [A ]/Kd vs ICS0 is not linear, other mechanisms of antagonism may be operative. If there is a nearly vertical relationship, this be due to noncompetitive antagonism in a system with no receptor reserve (see Figure 12.2d). Alternatively, if the plot is linear at low values of [A ]/Kd and then approaches an asymptotic value the antagonism may be allosteric (the value of a defines the value of the asymptote) or noncompetitive in a system with receptor reserve (competitive shift until the maximal response is depressed, Figure 12.2d). 

In addition to being smooth, it is preferable that the soil surface be firmly packed. This is because loose soil is not always retained in large-diameter sampling probes. Firming of the soil surface may be accomplished using a turf roller or equivalent. Alternatively, the soil surface may be prepared in advance of study initiation to allow rainfall or irrigation to settle and firm the soil. This latter approach also allows soil surface depressions to be observed and avoided when laying out the test plots. 

If the government s Pathfinder programme is a success, the problem of insufficient therapists may be solved. But what do we do in the meantime People who are depressed cannot wait until the year 2015 for help. Fortunately, there are some low-cost alternatives that are available right now. These are treatment approaches that are sometimes used in conjunction with psychotherapy, but can also be used as stand-alone treatments. Let us take a look at them. 

When the residual depression is mild to moderate, then the risks of using lithium are probably not warranted. A less aggressive approach using a safer but less proven augmenting medication is best. The alternatives include adding T3, buspirone, pindolol, a second antidepressant, a stimulant, estrogen, or an anticonvulsant. 

Thus, sleep deprivation may be an alternative somatic approach that holds promise for the treatment of certain depressive disorders, as well as being an aid in elucidating the biological basis of mood disorders (183). Further preliminary evidence indicates a role for sleep deprivation when used concomitantly or consecutively with antidepressants or with bright light therapy (184). 

Although severe disruption in the sleep-wake cycle is a common feature of dementia, the use of BZDs in such cases may also produce significant behavioral toxicity. Alternative drug approaches include bedtime use of olanzapine in nondepressed patients or trazodone in depressed patients. 

When a lai e munber of sunples are to be applied, the use of a template to position the spots accurately is often helpful. Alternatively, automated spotting equipment can be used to apply precise amoimts of sample in tiie position required, either in spots or bands. These devices have tiie disadvantage of being e q)ensive, difficult to clem, and usually requiring pre-concentiation of the sample. Another approach to sample application involves tiie evaporation of measured voliunes of the sample in depressions in a non-wettable poljmier fihn. When (hy, the residues are transferred to the plate by pressing the film on to it. It is a very good procedme where the solution is viscous or where it needs to be concentiated. 

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