The effect of prone positioning on maternal haemodynamics and fetal wellbeing in the third trimester-A primary cohort study with a scoping review

INTRODUCTION

Supine sleep position is associated with stillbirth, likely secondary to inferior vena cava compression, and a reduction in cardiac output (CO) and uteroplacental perfusion. Evidence for the effects of prone position in pregnancy is less clear. This study aimed to determine the effect maternal prone position on maternal haemodynamics and fetal heart rate, compared with left lateral position.

METHODS

Twenty-one women >28 weeks' gestation underwent non-invasive CO monitoring (Cheetah) every 5 minutes and continuous fetal heart rate monitoring (MONICA) in left lateral (20 minutes), prone (30 minutes), followed by left lateral (20 minutes). Anxiety and comfort were assessed by questionnaires. Regression analyses (adjusted for time) compared variables between positions. The information derived from the primary study was used in an existing mathematical model of maternal circulation in pregnancy, to determine whether occlusion of the inferior vena cava could account for the observed effects. In addition, a scoping review was performed to identify reported clinical, haemodynamic and fetal effects of maternal prone position; studies were included if they reported clinical outcomes or effects or maternal prone position in pregnancy. Study records were grouped by publication type for ease of data synthesis and critical analysis. Meta-analysis was performed where there were sufficient studies.

RESULTS

Maternal blood pressure (BP) and total vascular resistance (TVR) were increased in prone (sBP 109 vs 104 mmHg, p = 0.03; dBP 74 vs 67 mmHg, p = 0.003; TVR 1302 vs 1075 dyne.s-1cm-5, p = 0.03). CO was reduced in prone (5.7 vs 7.1 mL/minute, p = 0.003). Fetal heart rate, variability and decelerations were unaltered. However, fetal accelerations were less common in prone position (86% vs 95%, p = 0.03). Anxiety was reduced after the procedure, compared to beforehand (p = 0.002), despite a marginal decline in comfort (p = 0.04).The model predicted that if occlusion of the inferior vena cava occurred, the sBP, dBP and CO would generally decrease. However, the TVR remained relatively consistent, which implies that the MAP and CO decrease at a similar rate when occlusion occurs. The scoping review found that maternal and fetal outcomes from 47 included case reports of prone positioning during pregnancy were generally favourable. Meta-analysis of three prospective studies investigating maternal haemodynamic effects of prone position found an increase in sBP and maternal heart rate, but no effect on respiratory rate, oxygen saturation or baseline fetal heart rate (though there was significant heterogeneity between studies).

CONCLUSION

Prone position was associated with a reduction in CO but an uncertain effect on fetal wellbeing. The decline in CO may be due to caval compression, as supported by the computational model. Further work is needed to optimise the safety of prone positioning in pregnancy.

TRIAL REGISTRATION

This trial was registered at clinicaltrials.gov (NCT04586283).

Investigation of the outcome of pregnancies complicated by increased fetal movements and their relation to underlying causes - A prospective cohort study

INTRODUCTION

Retrospective studies have reported an association between a single episode of significantly increased fetal movements (IFMs) and stillbirth after 28 weeks' gestation. This prospective study aimed to report the outcome of pregnancies associated with maternal perception of IFMs and determine whether this symptom is associated with adverse pregnancy outcome, a pathological intrauterine environment or placental dysfunction.

MATERIAL AND METHODS

Women reporting IFMs after 28 weeks' gestation were recruited from St Mary's Hospital, Manchester and Liverpool Women's Hospital, UK, between 1 November 2017 and 1 May 2019. Demographic and clinical information were obtained and an ultrasound scan was performed to assess fetal biometry, liquor volume and umbilical artery Doppler. Maternal serum samples were collected for analysis of placentally derived biomarkers using ELISA. After delivery, maternal and fetal outcome data were collected and placentas and umbilical cord blood were obtained for analysis using immunohistochemistry and ELISA, respectively. Placental and serum samples were matched by gestation and maternal characteristics to participants with normal fetal activity.

RESULTS

Seventy-seven women presented with IFM, representing 0.45% of the maternity population; 64 women consented to participate in the study, of which 7 (10.9%) experienced adverse pregnancy outcome: birthweight <3rd centile, 2 (3.1%); pH ≤7.10, 1 (1.6%); neonatal intensive care unit admission, 4 (6.3%). Women had IFM for varying lengths of time before presenting: 17.2% had IFM for less than 1 hour and 29.7% reported IFM lasting longer than 24 hours. Four women (6.3%) had abnormalities of the fetal heart rate trace on assessment. Women with IFM had similar modes of birth to women giving birth in participating maternity units. There was no evidence of macroscopic placental or umbilical cord abnormalities, alterations in microscopic placental structure, placental endocrine dysfunction or intrauterine hypoxia or infection in women with IFM compared with controls.

CONCLUSIONS

This prospective study did not find evidence of an association between IFM and adverse pregnancy outcome. It also did not find evidence of underlying placental dysfunction, cord anomalies, intrauterine hypoxia or infection in pregnancies with IFM. Further work is required to determine the strength of association between IFM and adverse pregnancy outcome and its origins. At present, IFM cannot be used to identify fetuses at increased risk of adverse outcome.

Ultrafast X-Ray Diffraction Studies of the Phase Transitions and Equation of State of Scandium Shock Compressed to 82 GPa

Using x-ray diffraction at the Linac Coherent Light Source x-ray free-electron laser, we have determined simultaneously and self-consistently the phase transitions and equation of state (EOS) of the lightest transition metal, scandium, under shock compression. On compression scandium undergoes a structural phase transition between 32 and 35 GPa to the same bcc structure seen at high temperatures at ambient pressures, and then a further transition at 46 GPa to the incommensurate host-guest polymorph found above 21 GPa in static compression at room temperature. Shock melting of the host-guest phase is observed between 53 and 72 GPa with the disappearance of Bragg scattering and the growth of a broad asymmetric diffraction peak from the high-density liquid.

Campylobacter Species and Neutrophilic Inflammatory Bowel Disease in Cats

BACKGROUND

Inflammatory bowel disease (IBD) is a common cause of signs of gastrointestinal disease in cats. A subset of cats with IBD has neutrophilic inflammation of the intestinal mucosa.

HYPOTHESIS

Neutrophilic enteritis in cats is associated with mucosal invasion by microorganisms, and specifically Campylobacter spp.

ANIMALS

Seven cats with neutrophilic IBD and 8 cats with lymphoplasmacytic IBD.

METHODS

Retrospective review of duodenal biopsy specimens that were collected endoscopically for histologic examination. Cases were identified and selected by searching the histopathology archive for cats with a diagnosis of neutrophilic and lymphoplasmacytic IBD. Fluorescence in situ hybridization (FISH) targeting either all eubacteria or individual Campylobacter spp. was performed on archived samples. Neutrophils were detected on the same samples using a FISH probe for neutrophil elastase.

RESULTS

Campylobacter coli was present in (6/7) cats with neutrophilic IBD and in (1/8) cats with lymphoplasmacytic IBD (P = .009). Cats with neutrophilic IBD had significantly higher number of C. coli (median bacteria 0.7/hpf) in the mucosa than cats with lymphoplasmacytic IBD (median bacteria 0/hpf) (P = 0.002). Colocalization of neutrophils and C. coli was demonstrated, with C. coli closer to the neutrophils than any other bacteria (P < .001).

CONCLUSIONS AND CLINICAL IMPORTANCE

Identification of C. coli associated with neutrophilic inflammation suggests that C. coli is able either to produce compounds which stimulate neutrophils or to induce feline intestinal cells to produce neutrophil chemoattractants. This association should allow a directed therapeutic approach in cats with neutrophilic IBD, potentially improving outcome and reducing any zoonotic risk.

Endochondral fracture healing with external fixation in the Sost knockout mouse results in earlier fibrocartilage callus removal and increased bone volume fraction and strength

Sclerostin deficiency, via genetic knockout or anti-Sclerostin antibody treatment, has been shown to cause increased bone volume, density and strength of calluses following endochondral bone healing. However, there is limited data on the effect of Sclerostin deficiency on the formative early stage of fibrocartilage (non-bony tissue) formation and removal. In this study we extensively investigate the early fibrocartilage callus. Closed tibial fractures were performed on Sost(-/-) mice and age-matched wild type (C57Bl/6J) controls and assessed at multiple early time points (7, 10 and 14days), as well as at 28days post-fracture after bony union. External fixation was utilized, avoiding internal pinning and minimizing differences in stability stiffness, a variable that has confounded previous research in this area. Normal endochondral ossification progressed in wild type and Sost(-/-) mice with equivalent volumes of fibrocartilage formed at early day 7 and day 10 time points, and bony union in both genotypes by day 28. There were no significant differences in rate of bony union; however there were significant increases in fibrocartilage removal from the Sost(-/-) fracture calluses at day 14 suggesting earlier progression of endochondral healing. Earlier bone formation was seen in Sost(-/-) calluses over wild type with greater bone volume at day 10 (221%, p<0.01). The resultant Sost(-/-) united bony calluses at day 28 had increased bone volume fraction compared to wild type calluses (24%, p<0.05), and the strength of the fractured Sost(-/-) tibiae was greater than that that of wild type fractured tibiae. In summary, bony union was not altered by Sclerostin deficiency in externally-fixed closed tibial fractures, but fibrocartilage removal was enhanced and the resultant united bony calluses had increased bone fraction and increased strength.

Spatial control of bone formation using a porous polymer scaffold co-delivering anabolic rhBMP-2 and anti-resorptive agents

Current clinical delivery of recombinant human bone morphogenetic proteins (rhBMPs) utilises freeze-dried collagen. Despite effective new bone generation, rhBMP via collagen can be limited by significant complications due to inflammation and uncontrolled bone formation. This study aimed to produce an alternative rhBMP local delivery system to permit more controllable and superior rhBMP-induced bone formation. Cylindrical porous poly(lactic-co-glycolic acid) (PLGA) scaffolds were manufactured by thermally-induced phase separation. Scaffolds were encapsulated with anabolic rhBMP-2 (20 µg) ± anti-resorptive agents: zoledronic acid (5 µg ZA), ZA pre-adsorbed onto hydroxyapatite microparticles, (5 µg ZA/2% HA) or IkappaB kinase (IKK) inhibitor (10 µg PS-1145). Scaffolds were inserted in a 6-mm critical-sized femoral defect in Wistar rats, and compared against rhBMP-2 via collagen. The regenerate region was examined at 6 weeks by 3D microCT and descriptive histology. MicroCT and histology revealed rhBMP-induced bone was more restricted in the PLGA scaffolds than collagen scaffolds (-92.3% TV, p < 0.01). The regenerate formed by PLGA + rhBMP-2/ZA/HA showed comparable bone volume to rhBMP-2 via collagen, and bone mineral density was +9.1% higher (p < 0.01). Local adjunct ZA/HA or PS-1145 significantly enhanced PLGA + rhBMP-induced bone formation by +78.2% and +52.0%, respectively (p ≤ 0.01). Mechanistically, MG-63 human osteoblast-like cells showed cellular invasion and proliferation within PLGA scaffolds. In conclusion, PLGA scaffolds enabled superior spatial control of rhBMP-induced bone formation over clinically-used collagen. The PLGA scaffold has the potential to avoid uncontrollable bone formation-related safety issues and to customise bone shape by scaffold design. Moreover, local treatment with anti-resorptive agents incorporated within the scaffold further augmented rhBMP-induced bone formation.

A modular and optimized single marker system for generating Trypanosoma brucei cell lines expressing T7 RNA polymerase and the tetracycline repressor

Here, we present a simple modular extendable vector system for introducing the T7 RNA polymerase and tetracycline repressor genes into Trypanosoma brucei. This novel system exploits developments in our understanding of gene expression and genome organization to produce a streamlined plasmid optimized for high levels of expression of the introduced transgenes. We demonstrate the utility of this novel system in bloodstream and procyclic forms of Trypanosoma brucei, including the genome strain TREU927/4. We validate these cell lines using a variety of inducible experiments that recapture previously published lethal and non-lethal phenotypes. We further demonstrate the utility of the single marker (SmOx) TREU927/4 cell line for in vivo experiments in the tsetse fly and provide a set of plasmids that enable both whole-fly and salivary gland-specific inducible expression of transgenes.

Psittacid herpesvirus 3 infection in the eclectus parrot (Eclectus roratus) in Australia

Psittacid herpesvirus 3 (PsHV-3) has recently been implicated as the cause of a severe respiratory disease in Bourke's parrots (Neopsephotus bourkii) in the United States. In this report, the clinical manifestations and gross and microscopic lesions of PsHV-3 infection in 2 eclectus parrots (Eclectus roratus) in Australia are described. The presence of a PsHV-3 infection was confirmed by polymerase chain reaction amplification and sequencing of PsHV-3 DNA using degenerate and PsHV-3 primers. Electron microscopy of infected cells demonstrated the assembly of herpesvirus virions as well as intranuclear tubular structures. The detection of PsHV-3 in Australia in 2 eclectus parrots broadens the list of known affected species and confirms the presence of this virus in Australia.

Evaluation of a multifaceted intervention to limit excessive antipsychotic co-prescribing in schizophrenia out-patients

OBJECTIVE

To evaluate the effect of a multifaceted educational intervention on the frequency of antipsychotic co-prescribing in adult schizophrenia out-patients.

METHOD

Controlled quasi-experimental study performed in two Danish municipalities matched for baseline prevalence of antipsychotic polypharmacy, socioeconomic status and functional level of patients. The intervention was aimed at psychiatric healthcare providers and consisted of 1 day of didactic lectures, six 3-h educational outreach visits and an electronic reminder during drug prescribing.

RESULTS

Between-group use of antipsychotic polypharmacy was compared at baseline (intervention group, N = 232/control group, N = 351) and after 1 year of intervention (intervention group, N = 216/control group, N = 386). The prevalence of antipsychotic polypharmacy at follow-up was not significantly different between treatment settings when adjusting for differences in case-mix (P = 0.07).

CONCLUSION

This multifaceted educational intervention failed to reduce the frequency of antipsychotic co-prescribing, but it suggested that future efforts to improve prescribing practice should address organizational barriers to implementation.

Biological and ecological traits that assist establishment of alien invasive insects

In this study the biological and ecological traits of two groups of phytophagous insect pests were examined to determine attributes that may influence establishment in New Zealand Biological and ecological attributes of a group of insect species that is established in New Zealand were compared with species that are not currently established It was found that the species established in New Zealand had a significantly wider host plant range than species that have not established The lower developmental threshold temperature was on average 4C lower for established species compared with nonestablished species These data suggest that species that establish well in New Zealand have a wide host range and can tolerate lower temperatures compared with those that have not established

Climatic factors and bipolar affective disorder

In bipolar disorder, the factors provoking a new episode are unknown. As a seasonal variation has been noticed, it has been suggested that weather conditions may play a role. The aim of the study was to elucidate whether meteorological parameters influence the development of new bipolar phases. A group of patients with at least three previous hospitalizations for bipolar disorder was examined every 3 months for up to 3 years. At each examination an evaluation of the affective phase was made according to the Hamilton Depression Scale (HAM-D(17)), and the Bech-Rafaelsen Mania Rating Scale (MAS). In the same period, daily recordings from the Danish Meteorological Institute were received. We found no correlations between onset of bipolar episodes [defined as MAS score of 11 or more (mania) and as HAM-D(17) score of 12 or more (depression)] and any meteorological parameters. We found a statistical significant correlation between mean HAM-D(17) scores and change in mean and maximum temperature, and non-statistical significant correlations between mean MAS scores and rainfall plus atmospheric pressure, and non-statistical significant correlations between mean HAM-D(17) scores and hours of sunshine and cloudiness. Though meteorological factors may have an impact on triggering new episodes in bipolar patients, they do not constitute a dominant cause.

Analysis of a cross between green and red fluorescent trypanosomes

Trypanosoma brucei undergoes genetic exchange in its insect vector, but the mechanism is unknown and no one has yet seen the process. By crossing genetically engineered red and green fluorescent trypanosomes, we have been able to pinpoint the location of genetic exchange in the fly and search for intermediate stages. In experimental crosses of red and green parental trypanosomes, yellow hybrid trypanosomes first appeared in the fly salivary glands as early as 13 days after infection and were observed only in flies with a mixture of red and green trypanosomes in one or both salivary glands. Despite high numbers of flies with mixed infections, yellow trypanosomes were not detected in the fly midgut or proventriculus. The hybrid nature of yellow trypanosomes was confirmed by analysis of molecular karyotypes and microsatellite alleles. As well as yellow hybrids, hybrid trypanosomes with red, green or no fluorescence were also recovered from fly salivary glands. Analysis of microsatellite alleles in parental and progeny clones showed Mendelian inheritance. Our findings are consistent with the hypothesis that mating takes place between trypanosomes in the salivary glands of the fly before they attach to the salivary gland epithelium.

Effects of the cannabinoid CB1 receptor agonist CP55,940 and antagonist SR141716A on d-amphetamine-induced behaviours in Cebus monkeys

Several clinical studies have shown that alterations in the cannabinoid system in the brain may be associated with schizophrenia. Although evidence points towards an antipsychotic potential for cannabinoid antagonists, experimental studies have shown inconsistent behavioural effects of cannabinoid ligands within and across species. The aim of the present study was to explore these contradictory findings in a non-human primate model, predictive of antipsychotic efficacy in humans. The effects of the cannabinoid CB1 receptor antagonist SR141716A and the CB1 receptor agonist CP55,940 were explored in an d-amphetamine-based Cebus monkey model of psychosis. The monkeys were sensitive to extrapyramidal side effects (EPS), and the side-effect profiles of the drugs were explored as well. SR141716A (0.1, 0.25, 0.375, 0.5 and 0.75 mg/kg) and CP55,940 (0.0025, 0.005 and 0.01 mg/kg) were administered by subcutaneous injection alone and in combination with d-amphetamine (0.25mg/kg). SR141716A (0.1-0.5mg/kg) reduced d-amphetamine-induced arousal, while CP55,940 had no significant effect upon d-amphetamine-induced behaviours. No EPS were observed with either of these compounds. These data suggest that cannabinoid CB1 antagonists such as SR141716A may have limited antipsychotic potential in man as to positive symptoms. SR141716A administered alone induced anxiolytic-like behaviour, whereas administration of CP55,940 alone showed anxiogenic properties.

Multiple effects of the lectin-inhibitory sugars D-glucosamine and N-acetyl-glucosamine on tsetse-trypanosome interactions

We are studying early events in the establishment of Trypanosoma brucei in the tsetse midgut using fluorescent trypanosomes to increase visibility. Feeding flies with the lectin-inhibitory sugars D-glucosamine (GlcN) or N-acetyl-glucosamine (GlcNAc) has previously been shown to enhance fly susceptibility to infection with trypanosomes and, as expected, we found that both sugars increased midgut infection rates of Glossina morsitans morsitans with T. brucei. However, GlcNAc did not show the inhibitory effect on salivary gland infection rate reported previously for GlcN. Both sugars significantly slowed the movement of the bloodmeal along the midgut. GlcN also significantly increased the size of the bloodmeal taken and fly mortality. The most surprising finding was that GlcNAc stimulated trypanosome growth not only in the midgut, but also in vitro in the absence of any factor derived from the fly. Thus our direct comparison of the effects of GlcN and GlcNAc on the trypanosome-tsetse interaction has shown that these sugars impact on trypanosome growth and tsetse physiology in different ways and are not interchangeable as suggested in the literature. The sugars cause multiple effects, not restricted solely to the inhibition of midgut lectins. These findings have implications for current models of tsetse susceptibility to trypanosome infection.

The effects of dopamine D3 agonists and antagonists in a nonhuman primate model of tardive dyskinesia

Tardive dyskinesia (TD), a serious complication of antipsychotic dopamine (DA) antagonist treatment, has been hypothesised to develop due to a dominant DA D1 relative to DA D2 receptor function. Recent genetic and pharmacological studies implicate the DA D3 receptor in TD. The present study examined the role of the DA D3 receptor in relation to the DA D1/D2 imbalance hypothesis of TD in nonhuman primates. Eight Cebus monkeys displaying mild to severe TD due to previous chronic exposure to DA D2 antagonists were acutely injected with SKF 81297 (DA D1 agonist) 0.3 and 0.6 mg/kg, pramipexole (DA D3>D2 agonist) 0.025-0.1 mg/kg, CIS-8-OH-PBZI (DA D3 agonist) 5-10 mg/kg and SB-27701-A (DA D3 antagonist) 1-5 mg/kg and rated for oral dyskinesia. SKF 81297, 0.3 and 0.6 mg/kg, exacerbated TD. Pramipexole and CIS-8-OH-PBZI reduced SKF 81297-induced TD, while SB-27701-A had no effect. When administered alone, SB-27701-A increased TD relative to placebo, while pramipexole and CIS-8-OH-PBZI had no significant effect. Pramipexole did, however, ameliorate TD in those monkeys with severe TD. These results point towards a role of the DA D3 receptor in TD, but indicate that the DA D2 receptor may also play an essential role.

The muscarinic M1/M4 receptor agonist xanomeline exhibits antipsychotic-like activity in Cebus apella monkeys

Xanomeline is a muscarinic M(1)/M(4) preferring receptor agonist with little or no affinity for dopamine receptors. The compound reduces psychotic-like symptoms in patients with Alzheimer's disease and exhibits an antipsychotic-like profile in rodents without inducing extrapyramidal side effects (EPS) at therapeutically relevant doses. In the present study, we examined whether the xanomeline-induced functional dopamine antagonism found in rodent studies could also be observed in nonhuman primates. In addition, we studied whether the lack of EPS observed in rodents also applies to primates. To this end, we investigated the effects of xanomeline on the behavior induced by D-amphetamine and (-)-apomorphine in drug-naive Cebus apella monkeys. Antipsychotic compounds antagonize amphetamine-induced motor unrest and stereotypies in this species. Xanomeline inhibited D-amphetamine-induced motor unrest, stereotypies and arousal as well as apomorphine-induced stereotypies and arousal in drug-naive Cebus apella monkeys. Xanomeline did not induce EPS but vomiting occurred in some monkeys at high doses, in accordance with emetic events observed in Alzheimer patients following xanomeline administration. Even when xanomeline was tested in EPS-sensitized Cebus apella monkeys, EPS were not observed at the dose range of xanomeline used in the D-amphetamine-apomorphine combination study (0.5-3 mg/kg). However, when xanomeline was tested at 4 mg/kg, moderate dystonia was seen in two out of three monkeys. It is concluded that xanomeline inhibits D-amphetamine- and (-)-apomorphine-induced behavior in Cebus apella monkeys at doses that do not cause EPS. These data further substantiate that muscarinic receptor agonists may be useful in the pharmacological treatment of psychosis.

Aberrant behavioral effects of a dopamine D1 receptor antagonist and agonist in monkeys: evidence of uncharted dopamine D1 receptor actions

BACKGROUND

Basic research indicates a role for dopamine (DA) D1 antagonism in the treatment of schizophrenia. Clinical trials have not confirmed any role. Besides the defining second messenger (adenylyl cyclase [AC]), DA D1 receptors are linked to other effectors (e.g., phospholipase C [PLC]). Differing actions of DA D1 antagonists upon differing effectors could explain conflicting results between the lab/clinic.

METHODS

In a monkey model in which behavioral effects of DA D1 antagonists/agonists have been well characterized we examined: 1) SKF 83959, biochemically, a DA D1 antagonist, behaviorally a DA D1 agonist, and 2) SKF 83822, biochemically, a DA D1 agonist, which, unlike all previously tested DA D1 agonists, does not also stimulate PLC. SKF 83959 and SKF 83822 were given alone and combined with DA D1 and D2 agonists, antagonists, and dextroamphetamine (AMP).

RESULTS

SKF 83959 acted as a DA D1 agonist (induced oral dyskinesia given alone, counteracted DA D1 antagonist [NNC 756], induced dystonia, and did not inhibit AMP induced behaviors). SKF 83822, unlike previously studied DA D1 agonists, did not induce dyskinesia, but resulted in a state of extreme arousal and locomotor activation without stereotypy, effectively counteracted by NNC 756, but not by SKF 83959 nor raclopride (DA D2 antagonist).

CONCLUSIONS

It is hypothesized that: 1) dyskinesia is linked to PLC stimulation; 2) DA D1 agonism can play a role in the induction of psychosis, via a mechanism linked neither to AC nor PLC, and 3) DA D1 antagonists differ in antipsychotic potential, possibly via this unidentified mechanism.

Volatile compounds from Salix spp. varieties differing in susceptibility to three willow beetle species

The volatile compounds emitted by leaves of 10 willow varieties that differ in their susceptibility to damage by blue (Phratora vulgatissima), brassy (P. vitellinae), and brown (Galerucella lineola) willow beetles were examined both before and after mechanical damage and correlated with feeding preferences of these beetles determined under laboratory conditions. Three compounds were identified from intact undamaged leaves of six willow varieties, namely cis-3-hexenyl acetate, cis-3-hexenol, and benzaldehyde. After mechanical damage, the yield and number of volatile compounds increased for all varieties. There were significant differences among willow varieties for both the concentration of cis-3-hexenyl acetate and the relative proportion of this compound to cis-3-hexenol (green leaf volatile ratio). The 10 varieties collectively showed a significant negative correlation between the relative resistance of each variety to blue and brown willow beetles and the yield of cis-3-hexenyl-acetate from damaged plants. The green leaf volatile ratio of damaged plants was also negatively correlated with the relative resistance of willow variety to these two beetle species.

Extrapyramidal side effects during chronic combined dopamine D1 and D2 antagonist treatment in Cebus apella monkeys

Previous studies in non-human primates have shown that tolerance to dystonia occurs during chronic dopamine D1 (D1) but not D2 antagonism and induction/aggravation of oral dyskinesia (TD) during D2 but not D1 antagonism. We were therefore interested in determining the effects of combined chronic D1 + D2 antagonism on dystonia and dyskinesia. To this intent, 8 male Cebus apella monkeys were treated 10 weeks with gradually increasing doses of D1 antagonist (NNC 112) + a D2 antagonist (raclopride), followed by 2 weeks of treatment with the D2 antagonist alone. Due to previous neuroleptic exposure, 5 monkeys had TD and all were sensitized to dystonia. During the combined antagonist treatment, tolerance to dystonia occurred; the tolerance disappearing upon discontinuation of the D1 antagonist and continuation of the D2 antagonist alone. Parallel to these results, improvement of TD was seen during the combined antagonist treatment with worsening during the D2 antagonist alone. Both the combined antagonists and the D2 antagonist alone resulted in moderate/severe bradykinesia, with no tolerance. These findings indicate that supplementation of traditional D2 antagonism with a D1 antagonist would lessen the risk of dystonia and allow alleviation of preexisting TD, though parkinsonian side effects might still occur. The findings further indicate that separate dopaminergic mechanisms control dystonia/dyskinesia and parkinsonism.

New and old antipsychotics versus clozapine in a monkey model: adverse effects and antiamphetamine effects

RATIONALE

Neuroleptic primed Cebus apella monkeys have proven reliable in screening antipsychotics for extrapyramidal side effect (EPS) potential in humans, and the ratio EPS liability/antiamphetamine efficacy ["therapeutic index" (TI)] has fit well with clinical results.

OBJECTIVES

1) To find the TIs of one new (quetiapine), three potential [NNC 756 (dopamine (DA) D1 antagonist), NNC 22-0031 (alpha-1 adrenergic/5-HT2 serotonergic/DA D1 and D2 antagonist) and DOD 647 (DA D1 and D2 antagonist)] and three old antipsychotics (haloperidol, melperone and clozapine), 2) to test the model further and 3) to gain more insight as to clozapine's neuropharmacology.

METHODS

Seven monkeys received haloperidol daily for 2 years; all were sensitized to dystonia. All drugs were given SC, in increasing doses until two animals had dystonia/other adverse effects (AE), and in decreasing doses with a fixed dose of dextroamphetamine producing motor unrest and stereotypies, to find the minimum significant antiamphetamine dose (AA). The ratio AE/AA = TI.

RESULTS

Excepting clozapine and DOD 647, all drugs induced dystonia. At 2-4 mg/kg, clozapine caused uncoordinated movements, myoclonic jerks and rough tremor; unlike dystonia, the syndrome was not alleviated but worsened by the anticholinergic, biperiden. DOD 647 up to 2 mg/kg had no adverse effects. The TIs of the new and potential antipsychotics were 3-5 versus 4 for clozapine and 1 for haloperidol and melperone, suggesting that like clozapine, these new drugs will not produce EPS at antipsychotic doses.

Chronic dopamine D1, dopamine D2 and combined dopamine D1 and D2 antagonist treatment in Cebus apella monkeys: antiamphetamine effects and extrapyramidal side effects

To determine: (1) whether the apparent lack of efficacy of dopamine D1 (D1) antagonists in the clinic might be attributable to development of tolerance to antipsychotic effects; and (2) whether combined D1 and D2 antagonism might contribute to clozapine's clinical profile, eight Cebus apella monkeys were chronically treated with a D1 antagonist (NNC 756) ((+)-8-chloro-7-hydroxy-3-methyl-5-(7-(2,3- dihydrobenzofuranyl)-2,3,4,5-tetrahydro-1H-3-benzazepine), a D2 antagonist (raclopride) or a combination of the two antagonists. Prior neuroleptic exposure had resulted in oral dyskinesia in seven monkeys and sensitization to dystonia in all, yielding a model for acute and chronic extrapyramidal side effects (EPS). Dextroamphetamine-induced motoric unrest and stereotypies were used as a psychosis model. We found tolerance toward dystonic symptoms during D1 and D1 + D2 treatments but not during D2 treatment. D2 but not D1 or D1 + D2 antagonism caused exacerbation of dyskinesia. Both D1 and D1 + D2 antagonism were superior to D2 antagonism alone in counteracting the amphetamine-induced behaviors, with no tolerance to antiamphetamine effects. These findings suggest: (1) reasons other than tolerance (e.g., differences among antagonists) may explain the lack of efficacy in clinical trials with D1 antagonists; and (2) that D1 antagonism alone or combined and modest D1 and D2 antagonism offers the potential of antipsychotic efficacy with a lower risk of EPS than traditional D2 antagonism. Further clinical trials with D1 or combined D1 and D2 antagonists are, therefore, recommended.

Lea's Shield: a study of the safety and efficacy of a new vaginal barrier contraceptive used with and without spermicide

The purpose of this study was to evaluate the safety, efficacy and acceptability of Lea's Shield, a new vaginal contraceptive barrier device, when used with either spermicidal or non-spermicidal lubricant. One-hundred-eighty-five (185) women enrolled at six centers. Half were randomized to use the device with spermicide and half with a non-spermicidal lubricant. To be eligible, volunteers had to be 18-40 years old (inclusive), in good health with regular menses, sexually active in an ongoing relationship and at risk for pregnancy, and willing to use Lea's Shield as their sole means of contraception for six months. Participants were seen at admission, one week, one month, three months and six months. Gross cumulative life table rates were calculated for pregnancy and others reasons for discontinuation. Adverse experiences and responses to an acceptability questionnaire were evaluated. One-hundred-eighty-two (182) volunteers contributed data to the analysis of safety and 146 to that of contraceptive efficacy. The unadjusted six-month life table pregnancy rate was 8.7 per 100 women for spermicide users and 12.9 for non-spermicide users (p = 0.287). After controlling for age, center, and frequent prior use of barrier methods, the adjusted six-month life table pregnancy rate was 5.6 for spermicide users and 9.3 for non-spermicide users (p = 0.086), indicating that use of spermicide lowered pregnancy rates, although not significantly, during typical use. For purposes of comparison, it is important to note that this study differed from the cap/diaphragm and sponge/ diaphragm studies in that a high percentage (84%) of volunteers were parous. For reasons that are unclear, pregnancy rates among parous women using barrier contraceptives tend to be higher than among nulliparous women. Indeed, in this study there were no pregnancies among nulliparous users of Lea's Shield. Standardization of parity of this study population on those of the cap/diaphragm and sponge/diaphragm studies suggests that unadjusted pregnancy rates for this device would have been considerably lower (2.2 and 2.9 per 100 users of spermicide and non-spermicide, respectively) had the study been done using the populations of earlier studies. Since no directly comparative study has been done, these figures provide a tentative estimate of the relative efficacy of Lea's Shield compared with the sponge, cap, and diaphragm. There were no serious adverse experiences attributed to the use of Lea's Shield. Acceptability was very good. Seventy-five percent (75%) of women responded to an end-of-study questionnaire; 87% of these reported that they would recommend Lea's Shield to a friend. Lea's Shield is a new vaginal contraceptive that does not require clinician fitting. Pregnancy rates in this study compare favorably with other studies of barrier contraceptive methods including the cervical cap, diaphragm, and sponge, even though this study was done with greater rigor and with a greater percentage of parous women than previous barrier studies. Lea's Shield appears to be safe and very acceptable to study volunteers.

Extrapyramidal symptoms during long-term treatment with antipsychotics: special focus on clozapine and D1 and D2 dopamine antagonists

In schizophrenic patients in maintenance treatment, clozapine, compared to classic neuroleptics, induces relatively few extrapyramidal syndromes (EPS), especially less akathisia and tremor and usually no dystonia or rigidity. In patients with dyskinetic movements (acute or tardive) induced by other neuroleptics, clozapine may reduce or even remove dyskinesia or permit it to disappear. It cannot, however, be excluded that clozapine can induce dyskinesia in extremely rare cases, but it seems more likely that this is due to previous treatment with classic neuroleptics. The earlier clozapine is started, the less chance of development of dyskinesia. The low level of EPS with clozapine may be linked to the special receptor-binding profile of this drug: during treatment with therapeutic doses of clozapine, the level of D2 receptor blockade is too low (40% to 50% occupancy by positron emission tomography) to induce EPS, and the D1 receptor blockade (also 40% to 50% occupancy) has a lower EPS potential than D2 blockade. This binding profile may at the same time contribute to the special antipsychotic properties of clozapine. Other receptor affinities may contribute to the beneficial effect of clozapine in EPS and schizophrenia.

Clozapine versus typical antipsychotics. A retro- and prospective study of extrapyramidal side effects

Schizophrenic patients in long-term neuroleptic monotherapy with clozapine (n = 100) and perphenazine, flupenthixol or zuclopentixol (controls, n = 100) were evaluated for extrapyramidal side effects (EPS) (blind) as well as other side effects and mental condition (non-blind). In both groups the patients had received neuroleptic treatment for a total of 14 years (median) and the present antipsychotic (clozapine or control drug) for 5 years. Thus the clozapine-treated patients had previously received traditional neuroleptics for 9 years (median). The study was both retrospective (0.3-19 years for clozapine, 0.3-24 years for control drug, by means of chart information) and prospective (1 year, with video-controlled evaluation of EPS). There was a significantly lower prevalence of tardive dyskinesia (TD) in clozapine treated patients than control patients, although prior to this treatment there were more TD patients in the clozapine group (P < 0.05). This lower level of TD in the clozapine group was related to a lower induction of new cases (P < 0.001) and a tendency towards greater disappearance of TD in the clozapine than in the control group (P = 0.07). Clozapine treated patients without TD had started clozapine and ceased traditional neuroleptics at an earlier age than those with TD. Parkinsonian signs were seen in 33% of the clozapine patients versus 61% of the control patients, mainly as hypokinesia; tremor in 3% versus 11% and rigidity in 0 versus 19%. Psychic akathisia was found in 14% versus 40% and motor akathisia in 7% versus 29% of the patients, all differences significantly in favor of clozapine. Clozapine treated patients also had less neuroleptic-induced emotional indifference and depression, but more autonomic side effects than controls.

New antipsychotics: the present status

Until antipsychotics can be subdivided according to differentiated effects on psychic functions (for example on positive/negative symptoms and cognitive functions), the best classification seems to be one based upon receptor-binding profiles and the side effects that follow. Such a combined pharmacological-clinical approach appears fruitful to clinicians as well as pharmacologists. According to this classification the new antipsychotics can be subdivided into three main categories: the relatively pure dopamine antagonists (D2 antagonists, including sulpiride and amisulpiride); the dopamine (D2)-serotonin (5-HT2)-norepinephrine (alpha 1) antagonists (risperidone, ziprazidone and sertindole); and the multireceptor antagonists (clozapine, olanzapine and seroquel). Clozapine is still the most potent antipsychotic and the least potent at inducing extrapyramidal symptoms. New drugs such as olanzapine, seroquel and sertindole represent the further development of clozapine's positive qualities, while risperidone and ziprasidone are dominated to a greater extent by relatively traditional dopamine D2 receptor blockade.

The highly acidic C-terminal region of the yeast initiation factor subunit 2 alpha (eIF-2 alpha) contains casein kinase phosphorylation sites and is essential for maintaining normal regulation of GCN4

Regulation of the effective activity of eukaryotic initiation factor 2 (eIF-2) in protein synthesis is known to involve phosphorylation of its alpha subunit. Two mammalian enzymes, the haem-controlled repressor (HCR) and the double-stranded RNA-activated inhibitor (dsI), phosphorylate Ser-51 of the alpha subunit, thereby inhibiting the exchange of bound nucleotides on, and thus the recycling of, eIF-2. In Saccharomyces cerevisiae, the equivalent serine seems to be phosphorylated by the GCN2 protein kinase, which is activated by amino acid starvation. However, in the present paper we show that this is not the only site of phosphorylation in yeast eIF-2 alpha. We report the preparation of recombinant yeast eIF-2 alpha from Escherichia coli and its use in in vitro phosphorylation studies. Mammalian HCR and dsI are shown to phosphorylate specifically Ser-51 of yeast eIF-2 alpha, whereas extracts from yeast cells do not. Instead, at least one of three serine residue in the acidic C-terminal region of this protein is phosphorylated by fractions of yeast possessing casein kinase activities 1 and 2. A triple Ser-->Ala mutant form of yeast eIF-2 alpha was found to be no longer phosphorylated by either of the yeast (or mammalian) casein kinase activities in vitro. Isoelectric focusing of yeast extracts confirmed that the mutated sites normally act as sites of phosphorylation in vivo. The same mutant was used to show that the three sites have no essential function under normal physiological conditions in yeast. In contrast, deletion of the 13 amino acid long C-terminal region of eIF-2 alpha, including the three phosphorylation sites, led to derepression of GCN4 in vivo. Thus removal of the short, highly acidic C-terminal region of eIF-2 alpha has the same regulatory effect on translational (re)initiation as phosphorylation of the Ser-51 residue of the wild-type protein. This result provides new insight into the role of eIF-2 alpha activity in the regulation of translational (re-) initiation.

Motor and mental side effects of clozapine

Long-term experience with clozapine has shown that the agent has a motor and mental side effect profile that is distinct in many ways from classical neuroleptics. It can produce a parkinsonian-like bradykinesia and mild akathisia, but no rigidity and rarely tremor. In patients with tardive dyskinesia induced by other neuroleptics, clozapine permits the dyskinesia to disappear in about half the cases. That clozapine may induce tardive dyskinesia in extremely rare cases cannot be excluded, but it seems more likely that this tardive dyskinesia in clozapine-treated patients is due to previous treatment with classical neuroleptics. The earlier clozapine is started, the less chance for development of tardive dyskinesia. As do other neuroleptics, clozapine can elicit sedation and asthenia, but corresponding to the motoric extrapyramidal syndrome, clozapine causes emotional indifference ("mental parkinsonism"), depression, and restlessness to a significantly lesser degree, which may be of importance in the higher compliance seen with this drug.

Clozapine treatment in Denmark: concomitant psychotropic medication and hematologic monitoring in a system with liberal usage practices

BACKGROUND

Clozapine has been utilized in Denmark since the early 1970s. This study examines doses, concomitant psychotropics, and leukocyte counts.

METHOD

All psychiatric hospitals in Denmark were asked for copies of all their clozapine monitoring forms, which were then personally reviewed by the authors.

RESULTS

Forms from 656 patients were collected from 32 hospitals. The male/female ratio was 2/1; the median age, 38 years (range, 18-80). Thirty-five percent received concomitant antipsychotics, 28% benzodiazepines, 19% anticholinergics, 11% antidepressants, 8% antiepileptics, (carbamazepine, valproate, and phenobarbital), and 2% lithium. While there were no gender differences with respect to concurrent psychotropics, women received lower doses of clozapine than men (median dose, women 300 mg/day and men 400 mg/day, p < .02). Ten percent had had a neutrophil count < 2000/microL (3.2% < 1500/microL). Five percent had repeated neutrophil counts < 2000/microL (1.5% < 1500/microL). There were two cases of agranulocytosis; both patients fully recovered upon withdrawal of clozapine. Clozapine was discontinued because of hematologic abnormalities in only five other cases (0.8%).

CONCLUSION

While use of concomitant psychotropics during clozapine treatment should be limited because of an increased risk of complications, a totally restrictive policy might deprive certain patients of the benefits of clozapine treatment. There appears to be a benign form of granulocytopenia that does not always necessitate discontinuation, provided there is close follow-up.

Effects of several partial dopamine D2 receptor agonists in Cebus apella monkeys previously treated with haloperidol

Eight Cebus apella monkeys were treated with haloperidol for 2 years. Five monkeys had developed mild oral tardive dyskinesia and all were primed for neuroleptic induced dystonia, thus serving as a model for both chronic and acute extrapyramidal side effects. In this model, the partial dopamine D2 receptor agonists SDZ HDC-912, SDZ HAC-911, terguride, (-)-3-(3-hydroxyphenyl)-N-propylpiperidine) ((-)-3-PPP) and SND 919 were tested for extrapyramidal side-effect liability. Their antipsychotic potential was also tested, using a dose of dextroamphetamine producing mild stereotypy and moderate motoric unrest. For comparison, the dopamine D2 receptor agonist, LY 171555 and antagonist, raclopride were used. In contrast to the other drugs tested, SDZ HAC-911 consistently reduced oral activity, P < 0.05 (at doses from 0.005 to 0.025 mg/kg). The relative dystonic potencies were raclopride > SDZ HDC-912 > SDZ HAC-911 = terguride. Neither (-)-3-PPP nor SND 919 produced dystonia, but had observable dopamine D2 receptor agonistic effects, (-)-3-PPP producing emesis at 1-4 mg/kg and SND 919 producing motoric unrest and stereotypy at 0.05-0.25 mg/kg. Comparing the antiamphetamine effects of the more antagonist-like drugs with raclopride, the relative potencies were terguride = SDZ HAC-911 > SDZ HDC-912 > raclopride. Comparing the antiamphetamine effects of the more agonist-like drugs with LY 171555, the relative potencies were SND 919 > (-)-3-PPP > LY 171555 in relation to motoric unrest, while neither (-)-3-PPP nor LY 171555 produced inhibition of stereotypy.

Occupational stress and job satisfaction in the community dental service of north Wales: a pilot study

This study was conducted to measure levels of work pressure, job satisfaction and further factors related to occupational stress in community dental service staff in north Wales. The occupational stress indicator and a modified version of the dental work stress inventory were completed by 44 community dental service staff in March 1991. The community dental service staff showed poor levels of job satisfaction and psychosomatic indicators of stress. The perception of control of the individual's working practices was highly influenced by organisational demands. The best predictor of job satisfaction was perceived control followed by work pressures. The dental surgery assistants scored more unfavourably than their dental colleagues on most measures. Dentists consider clinical matters their greatest stress while dental surgery assistants were concerned principally with their working conditions such as pay levels and working hours. The study reflects a somewhat unhappy work situation for community dental service staff which may be temporary and in response to new administrative systems being introduced. A further in-depth assessment of staff is indicated to show whether these results are situation dependent or indicate a more permanent state.

Chronic treatment with the D1 receptor antagonist, SCH 23390, and the D2 receptor antagonist, raclopride, in cebus monkeys withdrawn from previous haloperidol treatment. Extrapyramidal syndromes and dopaminergic supersensitivity

The effects of chronic treatment with dopamine (DA) D1 and D2 receptor antagonists were evaluated in eight cebus apella monkeys with mild oral dyskinesia after previous haloperidol treatment. SCH 23390 (D1 antagonist) was given daily to investigate the direct behavioural effect during long-term treatment and the subsequent supersensitivity to DA agonists. Raclopride (D2 antagonist) was investigated for comparison. All drugs were given subcutaneously. SCH 23390 and raclopride induced dystonic syndromes, catalepsy, sedation and reduced locomotor activity. The monkeys developed marked tolerance to the dystonic effect of SCH 23390, while they showed increased sensibility to the dystonic effect of raclopride. Baseline oral dyskinesia (24 h after injection) remained unchanged during D1 antagonist treatment, while it increased during D2 antagonist treatment. SCH 23390 induced supersensitivity to the oral dyskinesia- and grooming-inducing effects of SKF 81297 (D1 agonist) after 9 weeks, while the subsequent treatment with raclopride induced supersensitivity to the reactivity- and stereotypy-inducing effects of quinpirole (D2 receptor agonist) after 3 weeks. Because of the possibility of a carry-over effect (SKF 81297-induced oral hyperkinesia and grooming), other changes in raclopride-induced behaviours cannot be ruled out. The development of tolerance to the dystonic effect of SCH 23390 and the unchanged baseline oral dyskinesia during SCH 23390 treatment indicate an advantageous profile of side effects of DA D1 receptor blockade.

Effect of D1 and D2 Agonists in Primates Withdrawn from Long-Term Treatment with Haloperidol

The effects of dopamine (DA) D1 and D2 receptor agonists were evaluated in eight Cebus apella monkeys. The monkeys had previously received haloperidol for 2 years, and five of the monkeys had developed mild oral dyskinesia. SKF 81297 (a full D1 agonist) induced marked oral hyperkinesia, consisting of tongue protrusions and licking or chewing movements, most pronounced in the monkeys with pre-existing oral dyskinesia. SKF 38393 and SKF 75670 (partial D1 agonists) also induced some oral dyskinesia, but to a lesser extent than SKF 81297, and with few licking movements. The partial D1 agonists, but not the full agonist, induced sedation. All of the D1 agonists induced grooming behavior, the full D1 agonist to the greatest extent. In the case of SKF 81297, the grooming was closely associated with the licking behavior. Quinpirole (a selective D2 agonist) and apomorphine (a mixed D1/D2 agonist) induced a hyperactive syndrome (nonoral stereotypy with rapid repetitive movements and increased arousal and locomotor activity). Quinpirole induced no grooming behavior and reduced pre-existing oral movements. The data indicate behavioral differences between D1 and D2 receptors and suggest that D1 receptors may be involved in the pathophysiology of some forms of dyskinesia syndromes.

The effects of dopamine D1 and D2 receptor agonists and antagonists in monkeys withdrawn from long-term neuroleptic treatment

The effects of dopamine D1 and D2 receptor agonists and antagonists were studied in eight Cebus apella monkeys previously treated with haloperidol for two years. SKF 81297 (specific D1 receptor agonist) induced oral hyperkinesia of variable intensity (P less than 0.01): some of the monkeys developed extreme lip smacking, tonque protrusions and licking movements while others developed only slight lip movements. A combined treatment of SKF 81297 with LY 171555 (full D2 receptor agonist) or SCH 23390 (D1 receptor antagonist) inhibited the oral hyperkinesia induced by SKF 81297 (P less than 0.01, P less than 0.02, respectively). Raclopride (D2 receptor antagonist) did not statistically change oral hyperkinesia (P less than 0.2), although five monkeys showed increased oral movements; most of these monkeys had pre-existing hyperkinesia. Treatment with SCH 23390 or raclopride resulted in an identical dystonic/cataleptic syndrome. SKF 81297 inhibited the dystonia induced by SCH 23390, while it did not significantly affect raclopride dystonia. The investigation indicates that oral dyskinesia may be related to an imbalance in D1 receptor and D2 receptor stimulation in favor of D1 receptors. The question now is whether D1 receptor antagonists, which may have antipsychotic potential, will produce tardive dyskinesia after long-term use.

Long-term experience with clozapine in Denmark: research and clinical practice

In Denmark, the use of clozapine has increased markedly (15-25% per year) since 1983, when the drug was relaunched--after its withdrawal in 1975. Several factors have contributed to this development: 1) the interesting pharmacology of clozapine, especially the atypical influence on dopamine transmission, including a relatively high D-1/D-2 receptor affinity ratio, 2) the potent anti-anxiety and anti-psychotic effect in severe and otherwise therapy-resistant psychotic patients, and 3) the lack of extrapyramidal side effects. A special monitoring form (for registration of total and differential leucocyte counts, ECG, body weight, drugs, doses and reason for possible withdrawal of the clozapine) is used in most Danish psychiatric institutions. This form secures the regular control of vital parameters and serves as an instrument for surveys of the use of clozapine in Denmark. Also, more selective studies are being carried out, e.g., on the effect of clozapine monotherapy versus combined therapy, and on the influence of clozapine on cardiovascular functions, including left ventricular output (echocardiography).