The misdiagnosis of conversion disorder in a psychiatric emergency service

During a 1-year period, 8400 patient presentations to a psychiatric emergency service were screened for the conversion symptom of extremity paresis/paralysis. Of 4220 unduplicated presentations, three patients had this complaint. These cases were reviewed and followed up. All had received a DSM-III diagnosis of conversion disorder, but in each case the patient's conversion symptom was attributed to organic disease. This had medicolegal consequences in one case and threatened legal consequences in the others. Although the frequency of this alleged conversion symptom was 0.07%, in reality it was 0.0%. Guidelines for the management of the alleged conversion symptom of paresis/paralysis are discussed.

Schistosoma mansoni: two-dimensional gel electrophoretic analysis of antigens uniquely immunoreactive with protective rat serum

Candidate vaccine antigens are defined by their differential immunoreactivity with antisera which are distinguishable by their capacity to confer passive resistance to infection. This "contrasting antisera" immunoassay has been successfully used in previous analyses of 4-week-old worm biosynthetically radiolabeled Schistosoma mansoni proteins to identify potentially protective antigens. Twice-infected Fischer (F-2x) and Wistar-Furth (W-2x) rat sera were the sources of protective and non-protective antibody, respectively. We have extended our original analysis by applying two-dimensional gel electrophoresis to resolve total and immunoreactive soluble proteins of the 4-week worms. Total proteins were characterized by silver staining and autoradiography. Radiolabeled protein antigens immunoprecipitated by F-2x and W-2x antisera were compared, and several were shown to be uniquely reactive with the protective immune serum. In a companion molecular approach to clone the candidate vaccine antigens, screening of a lambda gt11 adult S. mansoni cDNA expression library by the contrasting antisera assay has identified a clone (lambda 40) producing a fusion protein with epitopes uniquely reactive with F-2x. A rabbit antiserum to the lambda 40 fusion protein (anti-FP40) reacted with radiolabeled worm proteins in the 20-kDa size range. By 2D gel electrophoretic analysis, we can now demonstrate that anti-FP40 specifically immunoprecipitates most of the members of a multicomponent protein antigen subset 18-22 kDa in Mr, focusing over a pI range of 5.3-5.8, and recognized uniquely by F-2x.

Calcium in bacteria: a solution to which problem?

Calcium and calcium-binding proteins including those resembling calmodulin are implicated in numerous diverse processes in bacteria. These processes include chemotaxis, sporulation, virulence, the transport of sugars and proteins, phosphorylation, heat shock, the initiation of DNA replication, septation, nucleoid structure, nuclease activity and recombination, the stability of the envelope, and phospholipid synthesis and configuration. That such varied processes should have a common factor, calcium, suggests major underlying principles of calcium metabolism which have yet to be discovered.

Completed suicide in chronic pain

Although convergent lines of evidence indicate that one can expect a high rate of suicide completion for chronic pain patients, this problem has not previously been investigated. Follow-up data from our pain center revealed three chronic pain patients (two men and one woman) who completed suicide. These three cases are presented. The sequential nature of the data enabled us to calculate suicide rates for our chronic pain population and subsamples of this population: 16.5 women per year; 29.3 men per year; 57.1 white men and 34.9 white women in the age range of 35-64 years per year; and 78.6 white worker compensation men in the age range of 35-64 years per year. Calculation of the 95% confidence interval and comparison of these suicide rates to the general population of the United States using the Z statistic indicated that all chronic pain patient suicide rates were significantly greater than that of the general population. White men, white women, and white worker compensation men with chronic pain in the age range of 35-64 years are twice, three, and three times as likely, respectively, as their counterparts in the general population to die by suicide. Although no firm conclusions can be drawn because of the small suicide sample, these case reports indicate a need for further studies of chronic pain patient suicide rates at other pain centers.

Immunolocalization of a 110 kD molecule and a 150 kD molecule in rat incisor and mandibular bone

In the present study, antibodies against rat dental proteoglycans were used to characterize and localize the proteoglycans in rat incisor and mandibular tissues. Polyclonal rabbit antibodies were raised against a CPC-precipitated fraction of a sulfated dental extract. In unpurified dental extract these antibodies recognized two molecules of 110 kD and 150 kD. The 150 kD molecule was susceptible to chondroitinase ABC digestion but the 110 kD molecule resisted this enzymatic degradation. Immunocytochemically these two molecules were seen to be located in the pulp, the enamel organ and the mandibular bone. In each tissue only the periphery of the cells was stained and not the intracellular compartment. In the mineralized area of bone, dentin and forming enamel no staining was seen. These results indicate common epitopes in the proteoglycans from pulp, predentin, enamel organ and bone. Some differences were found in the nature of tooth and bone proteoglycans.

Analysis of a myosin-like protein and the role of calcium in the E. coli cell cycle

For a number of years now, we have argued that current models for the control of initiation of DNA synthesis, chromosomal partitioning and septum formation in Escherichia coli are unsatisfactory. Indeed, we could argue that despite considerable efforts, with the possible exception of dnaA and ftsZ, no genes specifically implicated in these control processes have been identified. In the cases of DnaA and FtsZ, no evidence has appeared to indicate how such molecules might be regulated to act once per cycle. In 1988, we formulated a specific proposal that the timing of cell cycle events in E. coli might be determined by a Ca++ flux, mediated by calcium-binding proteins and protein kinases and culminating, in the case of chromosome segregation and division, in the action of force-generating proteins such as myosin (Norris et al., 1988). In formulating this proposal, we took the view that the fundamental elements of cell cycle regulation are likely to be highly conserved across all species including prokaryotes. In this presentation, we shall describe the approaches we have been taking in order to test this hypothesis and to summarize the data obtained, in particular in relation to new genes identified which may play a role in the E. coli cell cycle. We shall also briefly indicate recent data from other laboratories consistent with our general hypothesis.

Concentrations and patterns of released pterins of various animal cell cultures

Neopterin, biopterin, pterin, 6-hydroxymethylpterin and isoxanthopterin were determined in the supernatants of various animal cell cultures. The different cell lines showed distinct variations in the concentrations as well as in the pattern and total amount of the released pterins. In cells from the same organ but from diverse species differences in pattern and release were found. Cell lines derived from primates had a high release of neopterin. A further difference resulted from the origin of fetal or adult organs. Neoplastic cell lines showed different patterns of pterins, dependent on the type of tumour. Primary cultures from embryonic bovine lung had the highest total amount of released pterins in all cell lines examined.

Co-distribution of annexin VI and actin in secretory ameloblasts and odontoblasts of rat incisor

Annexin VI and actin were detected by immunoblot analysis in the enamel- and dentin-related portions of dental tissues. Annexin VI was found mainly in the particulate fraction whereas actin was detected in both the soluble and particulate fractions. By immunoelectron microscopy, annexin VI antibodies conjugated with colloidal gold were seen to label the mitochondria, the cytosol and the nucleus of secretory ameloblasts and odontoblasts of rat incisor. In the processes of these cells, the plasmalemmal undercoat was labeled. Anti-actin antibodies labeled the desmosome-like junctions, the cytosol, and the mitochondria of the cell bodies. Extensive labeling was seen at the periphery of the Tomes' processes and odontoblast processes. These results suggest that annexin VI may play a role in Ca2(+)-regulation in the cell bodies, especially as a calcium receptor protein in the mitochondria. Moreover, annexin VI and actin seem to be co-distributed in secretory processes. Thus, these proteins might be both involved in exocytotic and endocytotic events.

Prenatal diagnosis of vein of Galen arteriovenous malformation by duplex sonography

Arteriovenous malformation of the vein of Galen, a rare disorder, has been diagnosed in several cases by in utero sonography. A case is presented in which the prenatal diagnosis of this entity was made by the combined use of real-time ultrasound and pulsed Doppler.

Ultrastructure of inter-odontoblastic fibres in the rat molar

Radially directed inter-odontoblastic collagen fibres were observed in ultra-thin sections of the radicular pulp/predentine complex of rat molars. Bundles of fibres crossed the distal junctional complexes of the odontoblasts, went through the whole thickness of the predentine and were incorporated into the mineralized dentine. Scanning electron microscopy showed that bundles of radial fibres are not found between the coronal odontoblasts of the rat molar but only in the root. The radial fibres were inserted into the predentine along vertical long-axial crests. The intercrest interval was not tightly fixed and the pattern of fibre-bundle insertion did not show a regular periodicity.

Water activity as a key parameter of synthesis reactions: The example of lipase in biphasic (liquid/solid) media

Ester synthesis catalyzed by Candida cylindracea lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) was investigated in solid/liquid biphasic media containing the enzyme preparation and reactants without addition of organic solvents not participating in the reaction. Although the effects of water on enzyme kinetics have been abundantly studied in nearly anhydrous media, reactions in which water is produced have not been investigated. The effect of water produced by the reaction itself on the enzymatic activity was studied. The dispersion of water in a shaken, nearly anhydrous medium was shown to be responsible for the lack of activity of the enzyme. In contrast, when slowly shaken, the enzyme was fully activated by the water furnished as a product of the reaction. However, when experiments were performed in a two-phase aqueous/organic system with previously solubilized enzyme in water, the enzyme activity was increased by shaking and was of the same order of magnitude as in nearly anhydrous media. Under low water activity conditions, a powerful agitation can lead to slower reaction rate, because water, a product of esterification, is not retained in the microenvironment of the enzyme to activate it. The activation effect of water produced by the reaction was clearly shown using enzyme preparations shaken in an anhydrous medium and previously equilibrated at low water activities (aw = 0.13 and 0.69). This activation did not occur for an enzyme preparation equilibrated at high aw (0.89) or for a preparation gently shaken in a water-saturated medium. The lag time preceding activation of the enzyme increased with the extent of enzyme dehydration.(ABSTRACT TRUNCATED AT 250 WORDS)

A radioautographic comparison of in vivo 3H-proline and 3H-serine incorporation in the pulpal dentine of rat molars: variations according to the different zones

3H proline and 3H serine were injected intraperitoneally to rats which were killed 4 and 24 hours later. The incorporation of the labelled precursors was studied in the odontoblasts, predentine and dentine of the first lower molars. After radioautography, statistically significant differences in grain density appeared between the furcation, occlusal and lateral areas of the pulp chamber. The incorporation of predentine components into dentine was faster in the lateral than in the occlusal area, the slowest being detected in the furcation area. These differences may be related to the distribution of occlusal forces in the rat molar.

Annexins I-VI in secretory ameloblasts and odontoblasts of rat incisor

Immunoblot analyses and ultrastructural immunogold studies have been conducted on annexins in the secretory ameloblasts and odontoblasts of the rat incisor. Annexins I and II were seen in the soluble and particulate fractions of the enamel-related portion but not in the dentin-related portion. These proteins were visualized in the cytosol, near to the plasma membrane of Tomes' processes and in secretory vesicles in the ameloblasts. The forming enamel was also labeled. Annexins III, VI an V were detected in both the soluble and particulate fractions of the enamel-and dentin-related portions. Annexin IV was mainly localized in the proximal and distal areas of the secretory ameloblasts and virtually absent from in the supranuclear area. Annexin V was mainly detected in the cytosol of the cells and to a lesser extent near the plasma membrane. Annexin VI was mainly detected in the particulate fraction of enamel- and dentin-related portions. It was seen in the mitochondria and in the subplasmalemmal undercoat. All these proteins may play a role in exocytosis and endocytosis. They are implied in the regulation of cell calcium, but not in the transfer of calcium through the cells in the direction of the forming enamel and dentin, except annexins I and II since they are both present in the secretory vesicles and in the forming enamel.

A new sensitive fluorometric assay for the metabolism of (--)-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene by human hair follicles

A new sensitive fluorometric assay was established to measure the stereospecific formation of benzo[alpha]pyrene tetrols formed after cytochrome P450-dependent metabolism of (--)-7,8-dihydroxy-7,8- dihydrobenzo[a]pyrene by human hair follicles. This simple assay requires three human hair follicles and a low (0.5-2.0 microM) substrate concentration and has a limit of detection of approximately 0.3 fmol of tetrols. Freshly isolated human hair follicles from 20 adult volunteers (10 non-smokers and 10 smokers) were assayed. While intersubject and seasonal variations were observed, the assay was found to be reproducible for a given subject. This rapid and non-invasive assay provides a new means for metabolic phenotyping of human subjects for their capacity to metabolize (--)-7,8-dihydroxy-7,8-dihydrobenzo[alpha]pyrene to its carcinogenic form (+)anti-benzo[a]pyrene diolepoxide.

Immunocytochemical evidence for an actin-myosin system in lens epithelial cells

Since filamentous actin had been shown earlier to exist in lens epithelial and fiber cells, we inquired whether this could represent a contractile system with myosin and other actin-associated proteins. We resolved this question in freshly removed or organ-cultured rabbit and squirrel lens epithelial whole mounts using immunocytochemical techniques and by immunoblots of extracts separated by electrophoresis. In the former, methods were developed using long fixation times and long incubation in primary antibodies and biotinylated second antibodies visualized by streptavidin immunofluorescence and by diaminobenzidine peroxidase. Myosin was found to be localized along the filamentous rays and at central vertices of polygonal arrays situated at the apices of epithelial cells. It was not clear whether myosin and actin occurred together along the same or adjacent filaments in a bundle. Tubulin and vimentin were found deeper in the cells and were not aligned with actin and myosin filaments. Control lens epithelia treated similarly except for deletion of the primary antibodies showed no staining. As positive controls, pieces of glycerinated sartorius muscle exhibited characteristic cross-banded patterns of actin and myosin when incubated with the same reagents used on the lens epithelium. Denatured extracts of rabbit lens epithelium and of cortical fiber cells separated by electrophoresis and transferred to nitrocellulose paper, stained specifically with the same myosin and tubulin antibodies used in the immunocytochemistry experiments. The molecular weight profile of the myosin polypeptide indicated that lens tissue has myosin II. We conclude that a contractile system exists in lens epithelial and cortical fiber cells, although the function is not understood at this time. We conjecture that the system may act to stabilize lens shape by providing contractile tone.

Visualization of glycosaminoglycans in rat incisor extracellular matrix using a hyaluronidase-gold complex

The enzyme-gold technique was used on dental tissues. Hyaluronidase was complexed with gold, and ultrathin sections of rat incisors were incubated with the hyaluronidase-gold complex to localize chondroitin-sulphate and hyaluronic acid at the ultrastructural level. The hyaluronidase-gold complex was found in predentine and dentine, especially at the mineralization front, in interglobular spaces and around dentinal canaliculi. The very young enamel was labelled, but not the later stages of formation. This method allowed a very precise localization of hyaluronic acid and/or chondroitin sulphate in rat incisors extracellular matrices. These findings support the important role of glycosaminoglycans in dentine mineralization.

In vitro studies on the action of CS-045, a new antidiabetic agent

The mechanism of action of CS-045, a new orally active antidiabetic agent, was studied in vitro using cultured hepatoma cells (Hep G2) and muscle cells (BC3H-1). Treatment of both types of cultured cells with varying doses of CS-045 did not significantly alter insulin receptor binding. Basal and insulin-stimulated glucose transport in BC3H-1 cells was also unaltered by the drug. In contrast, CS-045 increased glycogen synthase I activity in both cell types. This effect was maximal after 24 hours and in Hep G2 cells was associated with a threefold increase in the apparent affinity of the enzyme for glucose-6-phosphate. Gluconeogenesis from lactate in Hep G2 cells was greatly reduced by CS-045 treatment. We conclude that CS-045 may act directly on muscle and liver cells to increase glucose utilization. It is also effective in reducing glucose production. These multiple effects may account in part for the ability of CS-045 to reduce blood sugar levels in vivo.