Inhibition of murine hepatitis virus infections by the immunomodulator 2,3,5,6,7,8-hexahydro-2-phenyl-8,8-dimethoxy-imidazo[1,2a]pyridine (PR-879-317A).

PR-879-317A (2,3,5,6,7,8-hexahydro-2-phenyl-8,8-dimethoxy-imidazo [1,2a]pyridine) has been found to be a T-cell-selective immunomodulating agent. In the current studies, a series of experiments was designed to determine the potential antiviral activity of this compound in mice infected with murine hepatitis virus. In a comparative antiviral experiment, the activity seen was superior to that of levamisole, a known immunorestorative agent. This activity was characterized by an increase in the 21-day survival frequency, a decrease in hepatic discoloration, a decrease in the amount of infectious virus recoverable from the liver, and normalization of serum glutamic oxalacetate and pyruvate transaminase levels. A comparison of treatment routes indicated the relative efficacies as intraperitoneal greater than per os greater than intramuscular greater than or equal to subcutaneous. Alteration of the treatment schedule markedly affected the antiviral effect; prophylactic or therapeutic treatments once or twice daily for 3 days were usually effective. Single treatments begun 4 h before or 24 h after virus inoculation were highly efficacious. Three treatments administered on alternate days, beginning 48 h before virus inoculation, proved moderately effective. Thrice-daily treatments were ineffective, as were treatments with durations of greater than 3 days. The optimal dosage varied according to the treatment route and dosage schedule. When assessed for direct antiviral activity in vitro, PR-879-317A failed to demonstrate any significant activity against murine hepatitis virus. The positive in vivo activity noted might therefore be the result of immune modulation rather than a direct antiviral effect.     

Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results

In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients.     

Normative implications of the relationship between reading vocabulary and Boston Naming Test performance.

The 60-item Boston Naming Test (BNT) was published in 1983 with norms described as provisional. One recent finding (Thompson & Heaton, 1989) suggests that verbal intelligence, and the Wechsler Adult Intelligence Scale (WA1S)-Revised Vocabulary subtest, in particular, is strongly correlated with BNT performance, and that education is moderately so. High false-positive rates for naming deficit may conceivably result from the application of the published norms with subjects of lower verbal abilities or limited educational backgrounds. To further explore the relationship of naming to other verbal abilities, analyses were undertaken of the correlations between Level 7-9 Gates-MacGinite Reading Vocabulary Test (G-MRVT) and BNT data from 97 schizophrenic, bipolar, and normal subjects. Reading vocabulary is strongly correlated with BNT performance, and the nature of this relationship is essentially the same across the three diagnostic groups. Application of the published norms would have resulted in a high false-positive rate for naming deficit in all groups among subjects with reading vocabularies equivalent to twelfth grade or less. As a word-recognition based reading exercise, the G-MRVT is likely to provide a brain-compromise-resistant index against which the adequacy of naming performances can be assessed. Accordingly, G-MRVT based BNT performance expectation guidelines are presented for use as a complement to the published norms. Other implications are discussed.     

AANA Journal course: new technologies in anesthesia: update for nurse anesthetists--monitoring depth of anesthesia using a reliable esophageal method. (continuing education credit)

Until recently, there had been no simple, accurate, and reliable technique for monitoring depth of anesthesia, but now a monitoring system that measures lower esophageal contractility (LEC) is available. The system consists of a monitor and a disposable esophageal stethoscope equipped with provoking and measuring balloons. Since the brain stem directly controls the motor function of the esophagus, LEC was postulated to reflect the anesthetic state of the patient. Multiple-center clinical studies have shown that LEC correlates significantly with administered levels of intravenous and inhalation anesthetic agents and patient responses to surgical stimulation. Monitoring LEC permits the clinician to administer the dose of drug needed without the complications associated with "too deep" or "too light" anesthesia.     

The nitric oxide pathway in pre-eclampsia: pathophysiological implications

Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with N^G-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.