Quantitative autoradiographic characterization of L-[3H] glutamate binding sites in rat vestibular nuclei

Quantitative autoradiography has been used to characterize L-[3H] glutamate binding sites and to describe their distribution in frozen sections of rat vestibular nuclei. Scatchard plots and Hill coefficients of glutamate binding suggest that glutamate interacts with a single population of sites having a KD of about 126 nM and a capacity of 2.5 pmol/mg of protein. Although the level of glutamate binding was not very high compared to the highest levels described for some other brain regions, it was nonetheless substantial. The sites were distributed unevenly in the four vestibular nuclei and their distribution correlated well with the projection areas of the vestibular nerve, which has been described as a glutamate-mediated pathway. The highest numbers of glutamate binding sites were observed in the medial vestibular nuclei. This technique provides a very sensitive assay for characterizing the pharmacological subtypes of glutamate binding in the vestibular nuclei and for analyzing changes in these sites during development or after deafferentation of the vestibular nuclei.

Stratification of patients with metastatic prostate cancer based on extent of disease on initial bone scan

Most patients with metastatic prostate cancer will have metastasis to bone. Such patients are best monitored by serial radionuclide bone scans. One hundred sixty six men with bone metastasis from prostate cancer who received androgen deprivation therapy had their pretreatment bone scans reviewed using a semiquantitative grading system based upon the extent of disease (EOD) observed on the scan. The EOD on the scan correlated with survival. The 2-year survival rates for EOD I to IV were 94%, 74%, 68%, and 40%, respectively. The survival of patients in categories EOD I and IV significantly differed from the other categories. Men with metastatic prostate cancer entered into trials designed to evaluate the impact of treatment on survival should be stratified based upon the EOD on the bone scan. This analysis also indicates that patients in the EOD IV category have a particularly poor prognosis and may be candidates for alternative treatments.

Appearance and development of neuron-specific enolase immunoreactivity in organotypic cultures of mouse embryo otocysts

The appearance of neuron-specific enolase (NSE) immunoreactivity was studied in sensory and vestibular ganglion cells during the development of mouse embryo otocysts grown in vitro from the 13th gestation day. NSE appeared sequentially in the ganglion and sensory cell populations of the inner ear with a pattern that paralleled their successive maturation. Comparison with NSE immunoreactivity profile during in vivo development shows that NSE appears earlier during organotypic in vitro maturation.

In vitro differentiation of mouse embryo statoacoustic ganglion and sensory epithelium

Interactions between the statoacoustic ganglion and sensory vestibular epithelia have been investigated using different methods of organ and tissue cultures taken from mouse embryos on gestation day 13. Ultrastructural and biochemical observations of the degree of maturation of vestibular sensory cells and ganglion neurons grown in co-culture showed that these structures are able to replicate their in vivo ontogenic maturation and form specific 'functional' links, although anomalies in development were noted. The completion of ultrastructural sensory hair cell development in isolated otocyst organotypic culture is in agreement with previous findings supporting the hypothesis that nerve fibers do not exert any direct trophic influences on the survival and maturation of sensory epithelia. Morphological and immunocytochemical observations of vestibular and cochlear ganglion neuron differentiation in isolated cultures showed that these neurons can differentiate without their peripheral and central target structure. Possible interactions at earlier stages cannot be excluded. Further studies are needed to determine whether interactions between hair cells and ganglion cells can modulate their in vitro maturation under different experimental conditions.

Percutaneous angioplasty of atherosclerotic and postsurgical stenosis of carotid arteries

A technique for safe angioplasty of atherosclerotic stenosis of internal and common carotid arteries is described in which temporary balloon occlusion of the internal carotid artery is used to prevent cerebral embolization during manifestation of ulcerated plaques. Its successful use in six atherosclerotic stenosis is described. Five angioplasties of postsurgical stenoses are also reported in which the technique of temporary occlusion was not used. The future of carotid artery angioplasty is discussed.

Isolation of two strains of Kingella kingae associated with septic arthritis

Two new cases of infection, a presternal abscess and a spondylodiscitis caused by the recently classified bacterium Kingella kingae, are reported. The main bacteriological characteristics and the susceptibility of the two isolates to antimicrobial agents are described. The pathology of K. kingae, particularly among children, is reviewed.

[Effects of Ginkgo biloba extract on the morphological preservation of vestibular sensory epithelia in mice]

Oral or parenteral Ginkgo biloba extract seems to uniformly improve the ultrastructural qualities of vestibular sensorial epithelia when fixed by vascular perfusions. The improvements observed may be consequential to the effects of Ginkgo biloba extract on capillary permeability and general microcirculation, which would accelerate penetration of the fixator into vestibular tissues, and/or to more complex processes associated with cellular metabolism and membrane protective systems.

Anti-interleukin 2 receptor monoclonal antibodies. Respective role of epitope mapping and monoclonal antibody-receptor interactions in their antagonist effects on interleukin 2-dependent T cell growth

Functional studies, using mainly interleukin 2 (IL2)-dependent growth of human T cell lines or clones but also mixed lymphocyte cultures and mitogen T cell activation, allowed a collection of locally produced anti-IL2 receptor monoclonal antibodies (mAb) to be classified. They fell into two groups: one with strong to moderate inhibition of IL2, the other without any detectable functional activity in in vitro assays. Direct and sequential immunoprecipitation as well as peptide mapping confirm that all the mAb recognize the same surface molecule. The parameters responsible for such functional dichotomy were characterized: the main parameter was found to be linked to the epitopic cluster recognized on the molecule by the mAb. All functional mAb pertained to a given epitopic cluster and all the nonfunctional ones to an alternative cluster. Studies on mAb receptor and IL2 receptor interactions confirmed these findings and strongly suggest that functional mAb interact with a region on the IL2 receptor identical or very close to the site of ligand-receptor interaction. These data could facilitate the choice of mAb to be used in therapeutical approaches in vivo when ethical objections could be overcome by appropriate committees.

In vitro electrophysiological study of spontaneous activity in neonatal mouse vestibular ganglion neurons during development

Spontaneous discharges from vestibular ganglion neurons have been studied in mice between 0 and 10 days in freshly isolated in vitro preparations. The vestibular ganglion neurons were electrophysiologically active at birth with irregular activities. From the 3rd day. the activities could be divided into irregular and regular discharging units based on the coefficient of variation of their interspike intervals. This study provides two criteria for maturation of vestibular activities: a decreasing number of irregular units with age and an increase of the spontaneous discharge frequencies.

Intracavernous aneurysms: treatment by proximal balloon occlusion of the internal carotid artery

Seven patients with intracavernous aneurysms were treated by proximal balloon occlusion of the carotid artery, with no attempt to preserve carotid blood flow. After a 15-minute occlusion trial, two balloons were detached proximal to the neck of these aneurysms. Major clinical improvement occurred in six patients and no procedure-related complications were encountered (the follow-up period was 4-14 months). Because these aneurysms arise proximal to major collateral pathways, proximal carotid occlusions via endovascular techniques are simple and safe and carry with them little risk of thromboembolism.

Enzyme-linked immunosorbent assay using three different antigen preparations for detection of antibodies to Chlamydia trachomatis

The ability of an enzyme-linked immunosorbent assay (ELISA) to detect antibodies to Chlamydia trachomatis was evaluated in 100 sera using three different antigen preparations as substrates (sonicated organisms, Triton X solubilized antigen and SDS solubilized antigen). The results were compared to those obtained by a standard microimmunofluorescence assay. The results obtained by the three ELISA techniques and the microimmunofluorescence method were in relatively good agreement (76%); some discrepant results were observed in sera with a low antibody titer. There was good agreement of results obtained by the three ELISA techniques (84%). The microimmunofluorescence method showed the greatest sensitivity. Assuming the microimmunofluorescence method accurately demonstrates antibodies, the ELISA using Triton X solubilized antigen showed the highest degree of specificity (97%), and the ELISA with sonicated organisms the greatest sensitivity (82%) and accuracy (86%).

Carbohydrates detected by lectins in the vestibular organ

In the vestibular organ the presence of carbohydrates in the cupula and otoconia of young (6-day-old) and adult rats was investigated using fluorescent lectins. The following sugars have been identified in both young and adult rats: N-acetyl-glucosamine, galactose, mannose and fucose. In contrast, N-acetyl-galactosamine was not detected. In order to demonstrate the specificity of the reaction, control experiments were performed after preincubation of the lectin with its specific inhibitory sugar. The same sugars were identified in calcified (i.e. otoconia) and non-calcified (i.e. cupula) structures. The role of these sugars in the mineralization and fusion process of otoconia is discussed.

Sunflower seed protein: size and charge heterogeneity in subunits of the globulin fraction

The subunit heterogeneity of the globulin fraction of sunflower seeds was investigated by two dimensional electrophoresis, using isoelectric focusing in the first dimension and sodium dodecyl sulphate polyacrylamide gel electrophoresis in the second dimension. Under non reducing conditions, intermediary subunits B, C and D (molecular weight 54 000, 48 000 and 40 000, respectively) were focused within a pI range 5.4-6.0 but intermediary subunits A (molecular weight 60 000) focused within a pI range 6.3-6.8. Under reducing conditions the electrophoretic patterns show that intermediary subunits consist in large "acidic" and small "basic" subunits linked by disulphide bonds. The large subunits of B species are more acidic and less heterogeneous than the corresponding subunits of the A species. These results confirm that helianthinin had a "legumin-type" structure.

Benign collagenous nodule of the pleura associated with pleural plaques

We describe the radiographic, gross morphologic and microscopic appearance of a pleural collagenous nodule presenting as a "solitary nodule." We believe that this lesion is within the spectrum of "pleural plaques," an associated condition present in our patient who had a history of potential asbestos exposure. Awareness of this probably rare variant of a common abnormality may obviate the need for a diagnostic thoracotomy in certain circumstances.

Use of indirect calorimetry in the nutritional management of burned patients

The use of indirect calorimetry in assessing and monitoring nutritional support in burn patients is reported. Twenty-nine patients with a mean burn size of 35% TBSA were monitored with 228 measurements of resting energy expenditure (REE), calculations of respiratory quotient (RQ), and substrate metabolism. Daily weights, nitrogen balance determinations, and routine laboratory tests were also obtained. Oxygen consumption (VO2) was 186 +/- 39 ml/min/M2, corresponding to REE of 2,506 +/- 543 kcal/day. REE varied during the course of wound healing, demonstrating a biphasic course. Metabolic rate was also significantly increased with the performance of routine procedures such as dressings and surgery. Measurements of REE were a mean 76% of predictions based on the Curreri formula, and 1.47 times basal energy expenditure (BEE) calculated by the Harris-Benedict equation. Neither formula provided for the great variations observed in daily, and individual, measurements of REE. During the study, patients consumed 2,900 +/- 811 kcal/day, which exceeded REE by 1.14. This was associated with mean weight loss of 3.2% (range, -16 to 9%). RQ was less than 0.85 in 9% of determinations, but exceeded 1.0 24% of the time. Protein accounted for 17 +/- 3% of total metabolism, corresponding to a calorie:nitrogen ratio of 128:1. Practically, however, provision of this much protein proved difficult. Routine use of indirect calorimetry permits tailoring of nutritional support for burn patients, and is valuable in the early detection of significant under- or overnutrition.