BZ treatment

As with BZ, treatment with physostigmine was highly effective, restoring NF performance scores to about 60% of baseline. More vigorous treatment with higher physostigmine doses was found to have a greater effect. 

Both cholinomimetic and anticholinergic compounds reduced the retention of the label after [3h]BZ treatment In some areas of the brain The cholinomimetic compounds used were... 

Response to UVC Radiation and Bz. Similar features of the cellular response were examined after UVC + Bz treatm t as in the case of X or y rays + Bz (5). The results are summarized in Table 2. In contrast with LY-R cells and numerous other cell lines, LY-S cells were sensitized to UVC radiation by Bz. As in the case of X or y + Bz treatment, die distinct features of LY-S cell response to UVC + Bz treatment can be explained by low ligase I activity and hence, the necessity to activate ligase n. In LY-R cells, as in xeroderma pigmentosum cells (15), the rate of DNA incisions seems too low to activate poly(ADP-ribose) polymerase. On the other hand, LY-R cells may synthesize NAD+ more efficiently than LY-S cells (Table 1), and be able to maintain a stable NAD+ level in spite of poly(ADP-ribose) polymerase activation. In fact, when a double-labelling modification of the DNA unwinding method was used to examine the difference in sb frequency between Bz-treated and untreated UVC irradiated cells, the results were identical for LY-R and LY-S cells. We interpreted this as an indication of a Bz-sensitive base excision repair system (16,17) operating in both cell strains (in contrast with a nucleotide excision functional only in LY-S strain). Lack of nucleotide excision presumably makes LY-R cells sufficiently sensitive to UVC radiation that the base excision repair is not limiting for survival. 

Benzodiazepines. Several BZs have anticonvulsant activity and ate used for the treatment of epilepsy producing their anticonvulsant actions via interactions with the GABA /BZ receptor complex to enhance inhibitory GABAergic transmission (1). The anticonvulsant actions of the BZs tend to tolerate upon chronic usage in six months, and BZs also lead to withdrawal symptomatology. Other side effects include sedation, ataxia, and cognitive impairment. 

This subject has been reviewed by Noyes and Field,8 who give reference to the original formulation as well as a more explicit treatment. The presentation here will be given not in general terms but by means of one striking example, the oxidation of malonic acid by bromate ions catalyzed by cerium(IV). It is called the Belousov-Zhabotinsky (or BZ) reaction, after its discoverers.9 The stoichiometry of the reaction with excess malonic acid is... 

Chen Y, Dong BZ, Gao NY, Fan JC (2007) Effect of coagulation pre-treatment on fouling of an ultrafiltration membrane. Desalination 204 181-188... 

This reaction can oscillate in a well-mixed system. In a quiescent system, diffusion-limited spatial patterns can develop, but these violate the assumption of perfect mixing that is made in this chapter. A well-known chemical oscillator that also develops complex spatial patterns is the Belousov-Zhabotinsky or BZ reaction. Flame fronts and detonations are other batch reactions that violate the assumption of perfect mixing. Their analysis requires treatment of mass or thermal diffusion or the propagation of shock waves. Such reactions are briefly touched upon in Chapter 11 but, by and large, are beyond the scope of this book. 

FIGURE 37-2. Treatment alogorithm for GAD. SSRI = selective serotonin reuptake inhibitor BZ = benzodiazepine. (Reprinted, with permission, from reference 24.)... 

The BZs are the most frequently prescribed drugs for the treatment of acute anxiety (Table 68-9). All BZs are equally effective anxiolytics, and most of the improvement occurs in the first 2 weeks of therapy. They are considered to be more effective for somatic and autonomic symptoms of GAD, while antidepressants are considered more effective for the psychic symptoms (e.g., apprehension and worry). 

Treatment of acute anxiety generally should not exceed 4 weeks. BZs can be given as needed, and if several acute courses are necessary, a BZ-free period of 2 to 4 weeks should be implemented between courses. Persistent symptoms should be managed with antidepressants. 

Clonazepam is the most extensively studied BZ for treatment of generalized SAD. It improved fear and phobic avoidance, interpersonal sensitivity, fears of negative evaluation, and disability measures. Adverse effects include sexual dysfunction, unsteadiness, dizziness, and poor concentration. Clonazepam should be tapered at a rate not to exceed 0.25 mg every 2 weeks. 

Immediately after the trauma, patients should receive treatment individualized to their presenting symptoms (e.g., non-BZ hypnotic, short courses of CBT). Brief courses of CBT in close proximity to the trauma resulted in lower rates of PTSD. 

Most clinicians agree that the BZs are the drugs of choice in treatment of alcohol withdrawal. 

Alcohol withdrawal seizures do not require anticonvulsant drug treatment unless they progress to status epilepticus. Patients with seizures should be treated supportively. An increase in the dosage and slowing of the tapering schedule of the BZ used for detoxification or a single injection of a BZ may be necessary to prevent further seizure activity. 

The onset of withdrawal from long-acting BZs may be up to 7 days after discontinuation of the drug. Detoxification is approached by initiating treatment at usual doses and maintaining this dose for 5 days. The dose is then tapered over 5 days. Alprazolam withdrawal may require a more gradual taper. 

Several methods are available to access glycosyl iodides (Scheme 2.50). Anomeric hemiacetals bearing diverse protecting groups (Bn, Bz, Ac, N3, CMe2) upon treatment with a polymer-bound triphenylphosphine-iodine complex and imidazole can be converted into a-glycosyl iodides [179]. The precipitated by-products,... 

Other considerations were particularly important to military commanders. For example, how high a dose could the average person survive if no treatment were available How much would weather conditions - particularly heat - affect the likelihood of a fatal outcome Just how much BZ would a chemical officer in the field need to disseminate to achieve desired effects throughout a given area, and how much variation in dosage would each type of munition produce ... 

John was teamed with Eddie Clark in a two-part BZ study, designed to show the benefits of continuous physostigmine treatment after a dose of BZ slightly larger than would be required to produce incapacitation in the average subject. An intriguing feature of BZ is that doses below 5 mcg/kg never caused complete incapacitation, while doses at or above 7 mcg/kg almost always did. 

In 1962, we had not yet read any of the above reports. They came to our attention much later, after physostigmine had become our standard treatment for BZ and other belladonnoid intoxications. They all remain puzzling in some respects. 

Oral THA treatment 4 Apr-Jun 1962 oral high dose BZ fairly effective... 

Journal reports by Bell and Gershon indicated that tetrahydroaminoacridine (THA), a cholinesterase inhibitor, was effective in reversing delirium induced by Ditran (JB-329) as a form of psychiatric treatment It is interesting that their use of Ditran for this purpose was similar to the atropine coma treatment method reported more than a decade earlier by Forrer, Miller et al. In our study, five subjects were given 5.0 mcg/kg of oral BZ on two occasions, 8-14 days apart 60 mcg/kg of THA was administered iv four hours after the time of the second BZ dose. We observed definite partial reversal of impairment soon after injection, but it was brief. An unexpected observation was the general tendency by the subjects to become impaired more rapidly and intensely by BZ on the second occasion - a finding that was later confirmed in a more careful study. 

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