Lack of effects of prenatal exposure to lidocaine on development of behavior in rats

The objective of this investigation was to study the effects of lidocaine upon postnatal development of the rat. Lidocaine, 6 mg/kg (21 mumol/kg), was given to a group of 12 rats. Injections were administered intramuscularly, bilaterally in the masseter muscles, once a day on days 10 and 11 of pregnancy. Twelve control rats were given physiologic saline. Clinical signs, mortality, body weight, and food consumption were recorded during pregnancy and lactation. The duration of gestation was also recorded. The development of the offspring was monitored by tests of spontaneous activity, nociception, learning ability, and physical development. No clinical signs of adverse reactions were seen in any of the groups. In the majority of the learning ability tests, the control and lidocaine-treated groups showed similar results. However, in the schedule of differential reinforcement of low rates of responding (DRL 20), the lidocaine-exposed males received more reinforcements than the controls and made fewer responses. In the tests of nociception, a significant difference between sexes was recorded, in that the females were more sensitive than the males in the shock-titration test. Physical development, as monitored by swimming ability and spontaneous activity, showed no inter-group difference. The present results indicate that prenatal exposure to lidocaine fails to result in postnatal impairment of the development of behavioral performance of a wide range of tasks.     

Neuropsychological changes during steady-state drug use,withdrawal and abstinence in primary benzodiazepine-dependent patients

Impairment on neuropsychological tests during steady-state drug use and withdrawal, and after discontinuation of benzodiazepines, was studied in primary benzodiazepine-dependent patients. One group of patients was tested before and the other group after the initiation of a gradual tapering-off of the drug, and both groups were tested approximately 1 year later. At the initial assessment, both groups of patients showed impairment on most of the tests of general intelligence and on several of the tests in the Halstead-Reitan battery, as well as on a test of nonverbal memory, in comparison with healthy controls. At follow-up the patient groups had reached the level of the control group. This study confirmed earlier observations of neuropsychological deficits in long-term benzodiazepine-using patients and demonstrated that these changes are at least partly reversible by discontinuing drug intake.     

Ro 15-4513 does not antagonize the discriminative stimulus- or rate-depressant effects of ethanol in rats

Female rats, trained to discriminate between IP administered 1.2 g/kg ethanol (ETOH) and the saline vehicle (12 ml/kg), did not press the nondrug associated lever in tests with ETOH (0.9 and 1.2 g/kg) plus the purported amethystic imidazo benzodiazepine Ro 15-4513 (3 and 10 mg/kg) as examined at two intervals after ETOH administrations viz. 7.5 and 15 min. The two doses of Ro 15-4513 were administered 5 min prior to ETOH. Response times were increased in tests with the combination. ETOH in expired air was not different in the two drug conditions, i.e., ETOH singly and together with Ro 15-4513, irrespective of the dose combinations examined. Rats trained to press a bar (FR-10 operant behavior) for sweetened water disclosed increases in the time used to obtain the reinforcer after treatments with ETOH and Ro 15-4513. Thus, Ro 15-4513 did not seem to reverse any of the behaviors examined in this study.     

Acute tolerance to ethanol using drug discrimination and open-field procedures in rats

This study examined the phenomenon of acute tolerance to ethanol (ETOH) using drug discrimination learning (DDL), and open-field (OF) procedures. In DDL, rats were trained to discriminate between ETOH (1.2 g/kg) and saline. Doses of ETOH lower (0.6 and 0.9 g/kg), or higher (1.8 and 2.4 g/kg) than the training dose were tested to examine possible influence of ETOH pretreatment doses on the expression of acute tolerance. To assess concentrations of ETOH in the organism, a rebreathed air procedure was used. Equal concentrations after different ETOH doses were achieved by postponing the tests until sufficient time had elapsed. Only doses of ETOH higher than the training dose produced acute tolerance in the DDL procedure. For the response-time data no acute tolerance was observed. In the OF experiment, the occurrence of acute tolerance was examined for different spontaneous behaviours in drug-naive animals. At equal ETOH concentrations, the group examined during the descending phase of intoxication (1.8 g/kg, 60 min post-injection), reared significantly more than the group tested during the ascending phase (1.5 g/kg, 10 min post-injection). Other OF behaviours did not differ significantly between the two time intervals. Thus, it is suggested that acute tolerance is seen both in ETOH naive and in ETOH pre-exposed rats. However, in DDL acute tolerance was observed only when doses higher than the training dose of ETOH were evaluated.     

Composition of the Essential Oil of Agastache foeniculum

AGASTACHE FOENICULUM contains 0.1-0.3% essential oil and the main components are limonene, beta-caryophyllene, methylchavicol, and germacrene B (92% altogether). In addition 35 components, each accounting for less than 1% of the total essential oil, were identified.     

Probing the ability of the coat and vertex protein of the membrane-containing bacteriophage PRD1 to display a meningococcal epitope

Bacteriophage PRD1 is an icosahedral dsDNA virus with a diameter of 740 A and an outer protein shell composed of 720 copies of major coat protein P3. Spike complexes at the vertices are composed of a pentameric base (protein P31) and a spike structure (proteins P5 and P2) where the N-terminal region of the trimeric P5 is associated with the base and the C-terminal region of P5 is associated with receptor-binding protein P2. The functionality of proteins P3 and P5 was investigated using insertions and deletions. It was observed that P3 did not tolerate changes whereas P5 tolerated changes much more freely. These properties support the hypothesis that viruses have core structures and functions, which remain stable over time, as well as other elements, responsible for host interactions, which are evolutionally more fluid. The insertional probe used was the apex of exposed loop 4 of group B meningococcal outer membrane protein PorA, a medically important subunit vaccine candidate. It was demonstrated that the epitope could be displayed on the virus surface as part of spike protein P5.     

Absence of association between an intercellular adhesion molecule 1 gene E469K polymorphism and Alzheimer's disease in Finnish patients

Increased expression of intercellular adhesion molecule 1 (ICAM1), a protein known to contribute to inflammatory responses, has been detected in the brain tissue of patients with Alzheimer's disease (AD) and animals modelled to mimic AD or Parkinson's disease (PD). ICAM1 may, thus, be implicated in the pathogenesis of these disorders. Our purpose was to investigate whether genetic variants of the ICAM1 gene have a role in causing susceptibility to AD and/or PD. We genotyped the E469K polymorphism of ICAM1 in 196 AD, 52 PD and 202 control patients of Finnish origin. The distributions of the genotype and allele frequencies of the polymorphism did not differ significantly between the AD, PD or the control patients. We therefore conclude that the E469K polymorphism of ICAM1 is not a risk factor for AD or PD.     

Quantitative measurement of regional lung gas volume by synchrotron radiation computed tomography

The aim of this study was to assess the feasibility of a novel respiration-gated spiral synchrotron radiation computed tomography (SRCT) technique for direct quantification of absolute regional lung volumes, using stable xenon (Xe) gas as an inhaled indicator. Spiral SRCT with K-edge subtraction using two monochromatic x-ray beams was used to visualize and directly quantify inhaled Xe concentrations and airspace volumes in three-dimensional (3D) reconstructed lung images. Volume measurements were validated using a hollow Xe-filled phantom. Spiral images spanning 49 mm in lung height were acquired following 60 breaths of an 80% Xe-20% O2 gas mixture, in two anaesthetized and mechanically ventilated rabbits at baseline and after histamine aerosol inhalation. Volumetric images of 20 mm lung sections were obtained at functional residual capacity (FRC) and at end-inspiration. 3D images showed large patchy filling defects in peripheral airways and alveoli following histamine provocation. Local specific lung compliance was calculated based on FRC/end-inspiration images in normal lung. This study demonstrates spiral SRCT as a new technique for direct determination of regional lung volume, offering possibilities for non-invasive investigation of regional lung function and mechanics, with a uniquely high spatial resolution. An example of non-uniform volume distribution in rabbit lung following histamine inhalation is presented.