Prion protein expression in different species: analysis with a panel of new mAbs

By immunizing prion knockout mice (Prnp-/-) with recombinant murine prion protein (PrPc), we obtained a panel of mAbs specific for murine PrPc. These mAbs can be applied to immunoblotting, cell surface immunofluorescent staining, and immunohistochemistry at light and electron microscopy. These mAbs recognize both the normal (PrPc) and protease-resistant (PrPres) isoforms of PrP. Some mAbs are species restricted, while others react with PrP from a broad range of mammals including mice, humans, monkeys, cows, sheep, squirrels, and hamsters. Moreover, some of the mAbs selectively recognize different PrP glycoforms as well as the metabolic fragments of PrPc. These newly generated PrPc antibodies will help to explore the biology of PrPc and to establish the diagnosis of prion diseases in both humans and animals.

Different patterns of truncated prion protein fragments correlate with distinct phenotypes in P102L Gerstmann-Sträussler-Scheinker disease

The clinicopathological phenotype of the Gerstmann-Sträussler-Scheinker disease (GSS) variant linked to the codon 102 mutation in the prion protein (PrP) gene (GSS P102L) shows a high heterogeneity. This variability also is observed in subjects with the same prion protein gene PRNP haplotype and is independent from the duration of the disease. Immunoblot analysis of brain homogenates from GSS P102L patients showed two major protease-resistant PrP fragments (PrP-res) with molecular masses of approximately 21 and 8 kDa, respectively. The 21-kDa fragment, similar to the PrP-res type 1 described in Creutzfeldt-Jakob disease, was found in five of the seven subjects and correlated with the presence of spongiform degeneration and "synaptic" pattern of PrP deposition whereas the 8-kDa fragment, similar to those described in other variants of GSS, was found in all subjects in brain regions showing PrP-positive multicentric amyloid deposits. These data further indicate that the neuropathology of prion diseases largely depends on the type of PrP-res fragment that forms in vivo. Because the formation of PrP-res fragments of 7-8 kDa with ragged N and C termini is not a feature of Creutzfeldt-Jakob disease or fatal familial insomnia but appears to be shared by most GSS subtypes, it may represent a molecular marker for this disorder.

Effects of ketorolac tromethamine mouthrinse (0.1%) on crevicular fluid prostaglandin E2 concentrations in untreated chronic periodontitis

The effects of topical ketorolac tromethamine mouthrinse (0.1%) on gingival crevicular fluid (GCF) prostaglandin E2 (PGE2) concentrations were investigated in a 6-week, randomized, double-blind, placebo-controlled, parallel group, single center study of 42 patients with moderately advanced chronic adult periodontitis. Following screening, GCF was sampled from 6 sites per subject with filter paper strips and PGE2 levels measured using an enzyme immunoassay kit. Only those subjects with mouth median GCF PGE2 concentrations >30 ng/ml entered the rinsing phase. Eligible subjects were allocated placebo rinse in the first 2-week period (days 0 through 14), either ketorolac rinse (test group, n = 21) or placebo rinse (control group, n = 21) in the second 2-week period (days 14 through 28), and placebo rinse in the third 2-week period (days 28 through 42). Full mouth median GCF PGE2 concentrations were calculated for each subject at days 0, 14, 28, and 42, and group means were compared. From day 0 to day 14, no significant changes in GCF PGE2 concentrations were detected in either study group (P > 0.05). Utilizing mean GCF PGE2 concentrations at days 0 and 14 as covariates, no significant differences were observed in adjusted mean PGE2 levels at days 28 and 42 between the study groups (ANCOVA, P > 0.05). A statistically significant increase in GCF PGE2 levels was noted at days 28 and 42 in the placebo group (P < 0.01), but not in the ketorolac group (P > 0.05), when compared to baseline, however. GCF PGE2 levels were further studied in a subset of volunteers (n = 11) during a 12-hour period following first rinsing with mouthrinse (active or placebo) at day 14. GCF was sampled 0, 2, 4, 6, 8, and 12 hours post-rinsing. Mean PGE2 levels were higher in the placebo subgroup than in the ketorolac subgroup, and increased gradually over the 12-hour period in both subgroups. These data indicate that 1) 14 days of rinsing with 0.1% ketorolac mouthrinse controlled the elevation of GCF PGE2 observed in the placebo group but did not actually reduce GCF PGE2 concentrations and 2) changes in GCF PGE2 levels were not detectable in the 12-hour period following first rinsing with ketorolac.

Gerstmann-Sträussler-Scheinker disease with A117V mutation in a second French-Alsatian family

We report a kindred of French/Alsatian origin with symptoms of Gerstmann-Sträussler-Scheinker disease over 3 generations. In the propositus, cerebellar signs and memory disturbance were the presenting features, followed by other neurological manifestations. Biopsy of the cerebral cortex showed numerous multicentric and "kuru"-type amyloid plaques that on immuno-light and electron microscopy stained with antibody to prion protein. Molecular genetic analysis revealed an A117V mutation in the open reading frame of the prion protein gene. Questions as to pathology and spread of this mutation are discussed.

What do the basal ganglia do?

We propose that the basal ganglia support a basic attentional mechanism operating to bind input to output in the executive forebrain. Such focused attention provides the automatic link between voluntary effort, sensory input, and the calling up and operation of a sequence of motor programmes or thoughts. The physiological basis for this attentional mechanism may lie in the tendency of distributed, but related, cortical activities to synchronise in the gamma (30 to 50 Hz) band, as occurs in the visual cortex. Coherent and synchronised elements are more effective when convergence occurs during successive stages of processing, and in this way may come together to give the one gestalt or action. We suggest that the basal ganglia have a major role in facilitating this aspect of neuronal processing in the forebrain, and that loss of this function contributes to parkinsonism and abulia.

Memories of sexual abuse: Janet's critique of Freud, a balanced approach

Since the late nineteenth century explanations of sexual trauma have invoked unconscious mental mechanisms of forgetting. Memories have been seen as submerged only to be therapeutically recovered. Explanations and related therapies have tended to be either hotly advocated or decried, not the least were those of Janet and Freud. Once again there is a vigorous debate surrounding the status of recovered memories. This paper was undertaken to contribute to reasoned and balanced dialogue by exploring an historical dimension. There is a renaissance of interest in the oeuvre of Janet. In this article Janetian sources are examined in which he criticised Freud's views on sexual trauma and elaborated his own position, a position which is yet significant today.

Automatic cardiac output measurement (ACOM): clinical applications of a new noninvasive tool

This study sought to validate a new noninvasive method to measure cardiac output, in the clinical setting, using color Doppler flow integration. This method, the automatic cardiac output measurement (ACOM), using color Doppler was recently developed and validated in vitro. ACOM was performed at the aortic valve and in the left ventricular outflow tract in 106 subjects (60 men, mean age 52 +/- 18) and compared with the echocardiographic pulsed-wave Doppler and a 2-D volume method. In 14 patients the noninvasive methods were correlated with the thermodilution technique. ACOM was feasible in 101 subjects (95%). The correlation factor between the values obtained with ACOM in the apical 5-chamber view and apical long-axis view was 0.75 at the aortic valve and 0.74 in the left ventricular outflow tract. Interoperator variability for ACOM in the apical 5-chamber and apical long-axis views were 0.93 and 0.75, respectively. The best comparison of ACOM with the pulsed-wave echo-Doppler technique occurred in the apical long-axis view (n = 79, r = 0.62), whereas the correlation with the 2-D volume method was poor. The most favorable comparison of ACOM with the thermodilution technique (n = 14) was also obtained in the apical long-axis view (5.408 +/- 1.72 vs. 3.356 +/- 1.281/min. [mean +/- SD], r = 0.71). Assuming the thermodilution technique as 'gold standard', the pulsed-wave echo-Doppler technique showed a better correlation (5.408 +/- 1.72 vs. 4.664 +/- 1.281/min., r = 0.84). ACOM is a useful, reproducible, noninvasive tool for rapid automated measurements of cardiac output. There is, however, an underestimation when compared with the pulsed-wave Doppler echocardiography and the thermodilution techniques. Good 2-D echocardiographic images, adequate color filling of the outflow tract and high frame rates are prerequisites for accurate values. Further refinements of this new technique are needed to enhance its clinical value in the future.

Evaluation of a live attenuated recombinant virus RAV 9395 as a herpes simplex virus type 2 vaccine in guinea pigs

Recombinant virus RAV 9395 was constructed by deleting both copies of the gamma(1)34.5 gene, and the UL55 and UL56 open reading frames from herpes simplex virus type 2 (HSV-2) strain G. The potential use of RAV 9395 as an HSV-2 vaccine was investigated by evaluating the ability of RAV 9395 to protect guinea pigs from severe disease by HSV-2(G) challenge. RAV 9395 administered intramuscularly reduced both lesion development and severity in a dose-dependent manner in guinea pigs challenged with HSV-2(G). The frequency of reactivation of RAV 9395 from explanted dorsal root ganglia was low compared with that of HSV-2(G). Immunization with RAV 9395 at doses of 1 x 10(5) pfu and above generally precluded the establishment of latency by the challenge virus. The results presented in this report lend support for the development of genetically engineered live HSV vaccines.

Combined analysis of studies of the effects of the matrix metalloproteinase inhibitor marimastat on serum tumor markers in advanced cancer: selection of a biologically active and tolerable dose for longer-term studies

This combined analysis investigated the effect of marimastat, a specific inhibitor of matrix metalloproteinases, on markers of tumor progression measured in patients with advanced cancer. By defining the tolerability and biological activity of the drug, it aimed to establish an appropriate dose range for use in Phase III trials. Patients with advanced, serologically progressive ovarian, prostatic, pancreatic, and colorectal cancer were recruited into six nonrandomized, dose ranging, multicenter clinical trials in North America and Europe. The biological activity of marimastat was assessed by serial measurements of the serum tumor markers carcinoembryonic antigen, CA125, CA19-9, and prostate-specific antigen. Patients were recruited with tumor markers rising by more than 25% averaged over a 4-week screening period. A biological effect was defined as a level of tumor marker at the end of treatment no greater than at study entry; a partial biological effect was defined as a rise in the level of tumor marker over the treatment period of 0-25% per 4 weeks. Pharmacokinetic and safety data were collected and assessed as the studies progressed. All patients were followed up for survival.

Inhibition of stromal matrix metalloproteases: effects on breast-tumor promotion by fibroblasts

Co-injection of fibroblasts with human epithelial breast-tumor MCF7 cells in the presence of Matrigel enhances tumor growth in nude mice. While most of the matrix metalloproteinases (MMPs) have been shown to be produced by stromal cells, tumor cells such as MCF7 cells are unable to produce MMPs. We therefore, hypothesized that the tumor-promoting effect of fibroblasts could be related to their production of MMPs. In order to inhibit stromal proteases, over-production of TIMP-2 was induced in MCF7 cells by in vitro retroviral-mediated gene transfer. TIMP-2-producing MCF7 cells were then co-injected with fibroblasts into nude mice. Alternatively, we evaluated the effect of Batimastat, a synthetic inhibitor of MMPs, on the tumorigenicity of MCF7 cells co-inoculated with fibroblasts into nude mice. Both physiological (TIMP-2) and synthetic (Batimastat) inhibitors of MMPs were able to abolish the tumor-promoting effect of fibroblasts. On the contrary, they failed to modulate the tumorigenicity of MCF7 cells injected alone. Interestingly, Matrigel from which low-molecular-weight proteins or growth factors had been removed failed to favor the tumorigenicity of MCF7 cells inoculated with fibroblasts. These findings emphasize the importance of fibroblasts in cancer progression, and suggest that their role could be related at least in part to production of proteases which can induce the release of factors from the extracellular matrix.

African-Caribbean men remanded to Brixton Prison. Psychiatric and forensic characteristics and outcome of final court appearance

BACKGROUND

African-Caribbean men are over-represented in psychiatric and forensic services and in the prison population. A failure of community services to engage mentally ill African-Caribbean men and their presentation through the criminal justice system culminates in a repeated pattern of forensic service and criminal justice system contact.

METHOD

We carried out a cross-sectional survey during a one-year period of a sample of potentially mentally ill men remanded to HMP Brixton in south London. Men were interviewed to establish their place of birth, first language, socio-demographic profile, ethnicity, psychiatric diagnosis, levels of alcohol and substance misuse, criminality, violence involved in their index offence, past psychiatric and forensic contacts and outcome of court appearance.

RESULTS

Two hundred and seventy-seven men were interviewed. In comparison with White men, African-Caribbean men were more often diagnosed as having schizophrenia and were more often sent to hospital under a mental health act order. African-Caribbean men were remanded in custody despite more stable housing conditions and more favourable indices of lifetime criminality, substance misuse and violence.

CONCLUSIONS

Community services, including diversion schemes, should be especially sensitive to African-Caribbean men with schizophrenia who 'fall out of care', who are not diverted back into care and are therefore unnecessarily remanded.

Distribution and submicroscopic immunogold localization of cellular prion protein (PrPc) in extracerebral tissues

In transmissible spongiform encephalopathies (TSE), such as scrapie in animals and Creutzfeldt-Jakob disease in humans, the central event is the conversion of a host-encoded amyloidogenic protein (PrPc) into an abnormal isoform (PrPsc) that accumulates as amyloid in TSE brain. PrPc is a membrane sialoglycoprotein synthesized in the central nervous system and elsewhere. We have examined the ultrastructural localization of PrPc in numerous hamster and some human extracerebral tissues, by means of a post-embedding electron-microscopic method combined with immunogold labeling. In stomach, intestine, lung, and kidney from hamsters, and in stomach, kidney, and spleen from humans, immunogold labeling specific for PrPc is observed on various cellular substructures related to secretory pathways: Golgi apparatus, secretory globules, and plasma membrane. In mucous epithelial cells of stomach and intestine, PrPc appears to be concentrated in secretory globules, suggesting a role for PrPc in the secretory function of the digestive tract. The secretory aspect of PrPc may be a key to understanding the physiopathological mechanisms underlying TSE.

Creutzfeldt-Jakob disease in a husband and wife

A 53-year-old man died of sporadic Creutzfeldt-Jakob disease (CJD) after a 1.5-year clinical course. Four and a half years later, his then 55-year-old widow died from CJD after a 1-month illness. Both patients had typical clinical and neuropathologic features of the disease, and pathognomonic proteinase-resistant amyloid protein ("prion" protein, or PrP) was present in both brains. Neither patient had a family history of neurologic disease, and molecular genetic analysis of their PrP genes was normal. No medical, surgical, or dietary antecedent of CJD was identified; therefore, we are left with the unanswerable alternatives of human-to-human transmission or the chance occurrence of sporadic CJD in a husband and wife.

A new clinical technique for demonstrating changes in eye acceleration during horizontal saccades in patients with partial internuclear ophthalmoplegias

The eyelid-mounted accelerometer can pick up the acceleration waveform of the eye during horizontal eye movements. The acceleration profile comprises high-amplitude pulsatile activity in the saccade and changes in the level of background ocular microtremor related to eye position. Adducting saccades of 20 degrees were recorded in eight patients with partial internuclear ophthalmoplegias caused by multiple sclerosis and in eight age-matched healthy subjects. The initial pulse of acceleration activity was reduced by 85% in the patients. In the worst-affected cases, adducting saccades were associated only with an increase in the level of background ocular microtremor in the acceleration trace. The results confirm the hypothesis that an internuclear ophthalmoplegia is due to the loss of the pulse signal to ocular motor neurons, with preservation of the step signal in an adducting saccade.

Factors leading to a strike vote and strategies for reestablishing relationships

An extremely difficult contract negotiation between a collective bargaining unit and a hospital resulted in a vote to strike by the nursing staff before reaching a final agreement. The authors describe the factors that led up to the strike vote. Realistic yet optimistic strategies for developing a working relationship with the bargaining unit leadership and the nursing staff are described.

Early myoclonic status and outcome after cardiorespiratory arrest

It has been suggested that early myoclonic status after cardiorespiratory arrest is an agonal event. Here we describe three cases who developed early myoclonic status during a coma after cardiorespiratory arrest due to acute asthma. As consciousness improved, each patient developed Lance-Adams type multifocal myoclonus, but the eventual outcome was satisfactory. Only one patient needed assistance to walk, and all three were self caring. One patient had persistent dyscalculia. Early myoclonic status is not necessarily an agonal event, particularly when it follows arrest due to acute asthma or asphyxia.