SSRls

G. N. George, J. S. George and 1. J. Pickering, http //www-ssrl.slac.stanford.edu/exafspak.html... 

Part of the work reported herein was performed at SSRL, which is supported by the Department of Energy, Office of Basic Energy Sciences the National Science Foundation, Division of Materials Research and the National Institutes of Health, Biotechnology Resource Program, Division of Research Resources. 

Overview. Electrons orbiting in a magnetic field lose energy continually in the form of electromagnetic radiation (photons) emitted tangentially from the orbit. This light is called synchrotron radiation. The first dedicated synchrotron light source was the Stanford Synchrotron Radiation Laboratory (SSRL) (1977). Nowadays, many... 

This work was supported by a grant from the National Science Foundation (PCM 79-04915). JEH is the recipient of a National Science Foundation predoctoral fellowship. The synchrotron radiation used in many of these studies was provided by the Stanford Synchrotron Radiation Laboratory with the financial support of the National Science Foundation (under contract DMR 77-27489) in cooperation with the Department of Energy and by the National Institutes of Health SSRL biotechnology resource (RR-01749). 

The answer is a. (Hardman, p 444) This patient has the serotonin syndrome Serotonin is already present in increased amounts in synapses because of blockade of its reuptake by the SSRls. The amount of serotonin that is present is further increased when breakdown by MAO is inhibited. The serotonin syndrome can be life threatening. 

Table IV summarizes the results for the resist screening studies at SSRL. The resist candidates generally exhibited good sensitivity, Dg 5 < 50 mJ/cm2, and contrast, 7 = 1.5. Definitive conclusions regarding the effect of structure on sensitivity are made difficult by the fact that polymer molecular weight and poly-dispersity varied considerably from sample to sample and, since we found a very strong dependence of Dg 5 on these parameters, specific structural effects are obscured. Several generalizations can be made, however.

Figure 3. Photon energy distribution for x-ray beam line at SSRL.

No fine line exposures were performed at SSRL because a suitable x-ray mash was not available. However, the two best resist candidates based on the SSRL studies, P(MI-DiBrS) and P(MI-VBC), were imaged with a Pd-target x-ray stepper. The images shown in Figure 11 indicate that both resists are capable of at least 0.5 Mm resolution. 

X-Ray Absorption Spectroscopy (XAS). The XAS measurements were similar to those described elsewhere.Grazing incidence (GI)-XAS measurements were performed at beamline 11-2 at Stanford Synchrotron Radiation Laboratory (SSRL). A double Si(220) crystal spectrometer was used to select the energy of the synchrotron X-rays, and the beam size was set to 400 pm x 2 mm. The bandwidth of the spectrometer was about 1 eV. Routine procedures were used to optimize the positions of the samples so that the angle of incidence was about 0.17°, with the X-ray... 

I would like to thank my graduate students Joshua D. Carter, Yongquan Qu, and Rhiannon Porter for their contribution to this work. I also thank C. Echer and C. Song at the National Center for Electron Microscope (NCEM), and J. Rogers and the excellent staff at the Stanford Synchrotron Radiation Laboratory (SSRL) for experimental support. I am also grateful to DOE for support of both facilities. Acknowledgment is made to the Donors of The Petroleum Research Eund, administrated by the American Chemical Society, for partial support of this research. This work is also partially supported by the Camille and Henry Dreyfus Eoundation and the National Science Eoundation (CHE-0135132). 

SSRls Citalopram Escitalopram Flnoxetine Flnvoxamine Paroxetine Sertraline... 

Listing of antidepressants in traditional groupings. Abbreviations TCAs = tricyclic antidepressants MAOls = monoamine oxidase inhibitors SSRls = selective serotonin reuptake inhibitors. 

The traditional scheme is complicated by the fact that some antidepressants exhibit characteristics of more than one class. For example, clomipramine, a tricyclic antidepressant (TCA) with side effects and toxicity similar to other TCAs, works more like the selective serotonin reuptake inhibitors (SSRls). Similarly, venlafaxine and duloxetine, which are usually grouped with the atypical antidepressants, have a side effect and safety profile comparable to the SSRls. Although a classihcation system based on mechanism of action offers some advantage (see Table 3.7), even this scheme is limited by the fact that antidepressants that work in the same way may have widely divergent side effect and safety profiles. In the following discussion, the traditional classification system is adopted. Although fraught with problems and inconsistencies. 

Buspirone (Buspar). Buspirone is an anxiety-relieving medication that alters serotonin activity. When added to an antidepressant, buspirone may help treat the depression. It will also relieve anxiety and may reverse sexual side effects of a SSRl. Please refer to Chapter 5 Anxiety Disorders for more information regarding buspirone. 

The second factor includes symptomatic predictors of treatment response. It has long been recognized that MAOls, and now SSRls, are more effective than TCAs... 

The fourth factor influencing medication choice is the safety of the medication. This is especially important given the snicide potential of depressed patients. The newer antidepressants, inclnding the SSRls and so-called atypical antidepressants, are mnch safer in overdose than the older TCAs and MAOIs. In the case of the TCAs, ingestion of a 1-2 week snpply is lethal 50% of the time. 

It appears that SSRls and bnpropion are less likely than TCAs to indnce mania. Venlafaxine, perhaps becanse of its dnal effects on serotonin and norepinephrine like the TCAs, also appears to increase the likelihood of switching into mania. Rarely, if ever, shonld an antidepressant be nsed in bipolar patients withont concomitant treatment with a mood stabilizer. 

Newer Generation Antidepressants. All SSRIs have been shown effective in the treatment of panic disorder. Of these, flnoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft), as well as the SNRI venlafaxine ER (Effexor XR), have received FDA approval for the treatment of panic disorder. Because they are safer and easier to tolerate, SSRls/SNRls have largely supplanted the MAOIs and TCAs as standard treatments (along with benzodiazepines) for panic disorder. 

SSRls and SNRIs. The SSRl antidepressants, together with venlafaxine, have replaced the benzodiazepines as treatments of choice for GAD. Paroxetine and escitalopram are FDA approved for GAD, though it is generally believed that all SSRls and SNRIs are effective for GAD. Similar to the TCAs, SSRIs/SNRIs appear to be most effective for the intrapsychic symptoms of GAD but less effective than benzodiazepines for the somatic manifestations of the disorder. 

Despite its considerable efficacy, clomipramine has given way to the SSRls as a result of their more favorable side effect and safety profiles. Clomipramine, however, is often used as an augmenfafion sfrategy for OCD pafienfs who are partial responders to SSRl therapy. The effectiveness of this approach has not been verified in confrolled frials. Furthermore, coadministration of clomipramine with some of the SSRls can result in potentially dangerous drug interactions. 

SSRls. SSRI antidepressants have also received considerable scrutiny in the treatment of OCD. Fluoxetine, fluvoxamine, paroxetine, and sertraline are all approved by the FDA for the treatment of OCD. Current studies suggest that each of these medications is more effective for OCD when administered at the higher end of the therapeutic dose range, that is, fluoxetine 60-80 mg/day, fluvoxamine 200-300 mg/ day, paroxetine 40-60 mg/day, and sertraline 150-200 mg/day. No controlled studies are yet available regarding the use of citalopram or escitalopram for OCD. Refer to Chapter 3 for more information regarding SSRl antidepressants. 

Pindolol (Visken). A beta blocker known to potentiate serotonin activity via a distinct action on serotonin autoreceptors, pindolol has been reported in a controlled study to augment SSRl treatment in OCD patients who are partial responders. Pindolol is administered at a dose of 2.5 mg three times daily. It is generally well tolerated but low blood pressure, dizziness, and sedation can occur. 

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