Outpatient metrizamide myelography: prospective evaluation of safety and cost effectiveness

A group of 228 consecutive patients undergoing metrizamide myelography was prospectively evaluated for postprocedure symptoms. The observed prevalence of these symptoms concurs with previously reported inpatient studies, with the most common sequelae being exacerbation or onset of spine or extremity pain, headache, nausea, and paresthesia. Limitation of administered dose of metrizamide in lumbar myelography may slightly reduce the occurrence of common symptoms, but withdrawal of contrast medium at the completion of examination had no impact on their occurrence. There was a higher occurrence of paresthesia in cervical myelography, but otherwise there was no significant difference in symptoms between cervical and lumbar studies. Outpatient metrizamide myelography can be performed with relative safety with the potential for significant cost savings.     

US-guided percutaneous biopsy: use of a screw biopsy stylet to aid needle detection

Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions.     

Osteosarcoma: use of MR imaging and MR spectroscopy in clinical decision making

Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased.     

The place of simultaneous pharmacokinetic pharmacodynamic modeling in new drug development: trends and perspectives*

Summary— The potential applications in drug development of pharmacokinetic-pharmacodynamic modeling are numerous: optimal medication regimen, design of galenic forms, identification of specific effects of metabolites and enantiomers. Nevertheless, this methodology is presently under-used, as appears from an analysis of the literature. We examine this point as well as progress in both non-invasive pharmacodynamic measurement and specific experimental design that could lead to a future extension of PK-PD in toxicology and phase I drug development.     

优化处方工艺改善环扁桃酯胶囊装量差异及崩解时限

目的：改善环扁桃酯胶囊的装量差异及崩解时限。方法：以装量差异和崩解时限为考察指标。对环扁桃酯胶囊的处方工艺进行优化。结果：通过处方工艺优化，选用Avicel PH302作稀释剂，Ac-Di-Sol作崩解剂，可改善环扁桃酯胶囊的装量差异及崩解时限。结论：AvicelPH302具有极佳的流动性，在胶囊充填过程中，可以大大改善粉体的流动性，减小胶囊的装量差异。Ac-Di-Sol作为崩解剂的效果优于国产CMS-Na。明显缩短胶囊的崩解时间。     

Habituation, prepulse inhibition, fear conditioning, and drug modulation of the acoustically elicited pinna reflex in rats

A reliable component of the acoustic startle response in animals is a flexion of the ears, the pinna reflex. One goal of the present investigation was to develop a preparation and apparatus suitable for analyzing the pinna reflex in the awake rat. A second goal was to examine the pinna reflex under behavioral and pharmacological conditions known to affect other response systems, such as whole-body startle, and determine whether the pinna response is a valid model for analyzing behavioral plasticity. The amplitude of the pinna reflex in spinally transected rats was directly related to stimulus intensity and exhibited short-term habituation, prepulse inhibition, and enhancement by prior fear conditioning. Also, pinna response amplitude increased following systemic administration of strychnine and was decreased following clonidine. It is concluded that this preparation and response system are valid for studying various forms of behavioral modification. Implications of these findings are discussed in terms of the potential utility of this response system in investigating the cellular correlates of behavioral plasticity in mammals.     

Differential effects of dopamine agonists on acoustically and electrically elicited startle responses: comparison to effects of strychnine

This study sought to determine where drugs that are known to alter sensorimotor reactivity measured with the acoustic startle reflex ultimately act within the acoustic startle pathway. To do this, startle was elicited either acoustically or electrically within various nuclei believed to comprise the acoustic startle pathway. Direct infusion of serotonin into the subarachnoid space of the lumbar spinal cord increased acoustic startle and startle elicited electrically through the ventral cochlear nucleus (VCN) to a comparable degree. Subconvulsant doses of strychnine increased startle elicited acoustically or electrically through either the VCN or the nucleus reticularis pontis caudalis (RPC), pointing to a spinal locus of action of strychnine after systemic administration. In marked contrast, the dopamine agonists d-amphetamine and apomorphine consistently increased acoustic startle but actually depressed startle elicited electrically through the VCN or the RPC. These later results suggest that dopamine agonists increase sensorimotor reactivity measured with acoustic startle by acting on sensory rather than motor parts of the reflex arc.