Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm

We present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{μ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{μ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{μ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{μ}≡(g_{μ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{μ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both μ^{+} and μ^{-}, the new experimental average of a_{μ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

Homozygous 15q13.3 microdeletion in a child with hypotonia and impaired vision: A new report and review of the literature

Although there are numerous reports of heterozygous 15q13.3 microdeletion, homozygous 15q13.3 microdeletion is rare. We report a new patient with homozygous microdeletion of 15q13.2q13.3 and review the previous literature reports. Common clinical features include encephalopathy, hypotonia, developmental delay, cortical vision impairment, optic nerve abnormality, epilepsy, and abnormal electroencephalogram (EEG) findings.

Development of methods for the preparation of radiopure 82Se sources for the SuperNEMO neutrinoless double-beta decay experiment

A radiochemical method for producing 82Se sources with an ultra-low level of contamination of natural radionuclides (40K, decay products of 232Th and 238U) has been developed based on cation-exchange chromatographic purification with reverse removal of impurities. It includes chromatographic separation (purification), reduction, conditioning (which includes decantation, centrifugation, washing, grinding, and drying), and 82Se foil production. The conditioning stage, during which highly dispersed elemental selenium is obtained by the reduction of purified selenious acid (H2SeO3) with sulfur dioxide (SO2) represents the crucial step in the preparation of radiopure 82Se samples. The natural selenium (600 g) was first produced in this procedure in order to refine the method. The technique developed was then used to produce 2.5 kg of radiopure enriched selenium (82Se). The produced 82Se samples were wrapped in polyethylene (12 μm thick) and radionuclides present in the sample were analyzed with the BiPo-3 detector. The radiopurity of the plastic materials (chromatographic column material and polypropylene chemical vessels), which were used at all stages, was determined by instrumental neutron activation analysis. The radiopurity of the 82Se foils was checked by measurements with the BiPo-3 spectrometer, which confirmed the high purity of the final product. The measured contamination level for 208Tl was 8–54 μBq/kg, and for 214Bi the detection limit of 600 μBq/kg has been reached.

Seizure and epilepsy publication in nonneurology journals

PURPOSE

The prevalence and characteristics of seizure and epilepsy research published in nonneurology journals are unknown. Characterizing this published research allows for insight into the relevance of seizures and epilepsy in other specialties and may increase opportunity for cross-specialty collaboration.

METHODS

In this observational study, we reviewed the top five highly cited clinical journals within eleven specialties in the InCites Journal Citation Reports (JCR) database (2016). For each specialty, we collected 2013-2017 PubMed data on publications with MeSH Major Topic of "seizures," "epilepsy," or "status epilepticus." Medical subject headings (MeSH) in PubMed are standardized terms assigned by subject analysts. MeSH Major Topic identifies articles in which a specified topic is the major focus of the article. We also retrieved author country and medical specialty affiliations. We analyzed whether author specialty affiliation was 1) concordant with journal medical specialty, 2) neurology-related, or 3) other.

RESULTS

Articles on "seizures," "epilepsy," or "status epilepticus" had the following prevalence in specialty clinical journals: cardiac and cardiovascular systems (0.01%); clinical neurology (5.34%); critical care medicine (0.20%); emergency medicine (0.47%); general and internal medicine (0.44%); neuroimaging (2.05%); neurosurgery (2.23%); obstetrics and gynecology (0.16%); oncology (0.01%); pediatrics (0.69%); and psychiatry (0.23%). Within general and internal medicine, neuroimaging, and pediatrics, seizure-related articles are more likely to be first-authored by someone with a neurology-related affiliation. Within critical care medicine, emergency medicine, neurosurgery, and obstetrics and gynecology, seizure-related articles were more likely to be first-authored by someone whose affiliation is within the field.

CONCLUSIONS

Our study characterizes seizure and epilepsy research published in nonneurology journals. We found that there is a paucity of such research published in nonneurology journals, whether authored by neurologists or other specialists. This is not ideal since nonneurologists are often first-line providers for recognizing, diagnosing, or managing seizures prior to assessment by a neurologist. Cross-specialty collaboration should be strongly encouraged in clinical research.

Search for Neutrinoless Quadruple-β Decay of ^{150}Nd with the NEMO-3 Detector

We report the results of a first experimental search for lepton number violation by four units in the neutrinoless quadruple-β decay of ^{150}Nd using a total exposure of 0.19 kg yr recorded with the NEMO-3 detector at the Modane Underground Laboratory. We find no evidence of this decay and set lower limits on the half-life in the range T_{1/2}>(1.1-3.2)×10^{21}  yr at the 90% C.L., depending on the model used for the kinematic distributions of the emitted electrons.

The BiPo-3 detector

The BiPo-3 detector is a low radioactive detector dedicated to measuring ultra-low natural contaminations of ²⁰⁸Tl and ²¹⁴Bi in thin materials, initially developed to measure the radiopurity of the double β decay source foils of the SuperNEMO experiment at the μBq/kg level. The BiPo-3 technique consists in installing the foil of interest between two thin ultra-radiopure scintillators coupled to low radioactive photomultipliers. The design and performances of the detector are presented. In this paper, the final results of the ²⁰⁸Tl and ²¹⁴Bi activity measurements of the first enriched ⁸²Se foils are reported for the first time, showing the capability of the detector to reach sensitivities in the range of some μBq/kg.

Knowledge of epilepsy and preferred sources of information among elementary school teachers

We conducted an online survey of elementary school teachers in Washtenaw County, Michigan, regarding their confidence in their knowledge of epilepsy and their preferred media or sources of information about epilepsy. Eighty-three teachers (9.3%) responded. One quarter expressed a lack of confidence in their ability to teach students with epilepsy or to respond appropriately to a seizure. Teachers most frequently (68%) cited the Internet as their primary source of information about epilepsy, with the school nurse and parents/guardians also frequently mentioned (55% and 48%, respectively). In contrast, most respondents prefer that their information come from the school nurse (74%) or a physician (73%), while only 25% cited the Internet as a preferred source. Teachers most frequently indicated EpilepsyFoundation.org (70.5%) as a trusted source of information. Future collaborative education efforts between school nurses and physicians, especially through use of the Internet, could improve teachers' knowledge of epilepsy.

Acute unilateral ophthalmoplegia as the presenting sign of acute myeloid leukemia in a 15-month-old girl

Central nervous system manifestations of acute myeloid leukemia are rare at presentation. Acute cranial nerve findings on neurologic examination can be indications for brain imaging. Magnetic resonance imaging can highlight cranial nerves emerging from the brainstem, particularly if they are gadolinium-enhanced or thickened. We describe a 15-month-old girl with acute unilateral ophthalmoplegia as the presenting sign of acute myeloid leukemia. Her presentation emphasizes the importance of appropriate laboratory and radiographic evaluation in a toddler with new-onset strabismus, which may be discounted as a previously unrecognized or benign finding.

Measurement of the ββ decay half-life of 130Te with the NEMO-3 detector

We report results from the NEMO-3 experiment based on an exposure of 1275 days with 661 g of (130)Te in the form of enriched and natural tellurium foils. The ββ decay rate of (130)Te is found to be greater than zero with a significance of 7.7 standard deviations and the half-life is measured to be T(½)(2ν) = [7.0 ± 0.9(stat) ± 1.1(syst)] × 10(20) yr. This represents the most precise measurement of this half-life yet published and the first real-time observation of this decay.

Pathways into receiving a prescription for diamorphine (heroin) for the treatment of opiate dependence in the United kingdom

In the UK, few doctors prescribe diamorphine for the treatment of opiate dependence to a small number of patients. A retrospective case note review of patients receiving diamorphine in 2000 was conducted in the UK to determine how and why these patients came to receive a prescription for diamorphine. Patient eligibility criteria were examined together with doctors' stated reasons for initiating a diamorphine (heroin) prescription. Two hundred and ten sets of patients' case notes were reviewed at 27 of the 42 (64%) drug clinics in England and Wales where diamorphine was prescribed by the doctor. There appeared to be a general consensus among the few doctors who had prescribed diamorphine that it was a treatment of last resort, for those with long histories of heroin use and injecting, and those who had not responded sufficiently well to previous other treatments. However, there was also a small number of patients initiated on diamorphine without ever having previously received opiate treatments and some because they were experiencing problems injecting methadone. This reflects the UK history of the individual doctor's clinical autonomy in deciding when diamorphine is appropriate and the previous lack of nationally agreed patient eligibility criteria.

Patients receiving a prescription for diamorphine (heroin) in the United Kingdom

The United Kingdom is unusual internationally in that it is one of few countries able to prescribe diamorphine for the treatment of opiate dependence. Prescribing diamorphine has been part of the UK response to drug problems since the 1920s. Despite this, little is known about who receives diamorphine and how treatment is delivered. This study aims to describe the characteristics and treatment regimes of opiate-dependent drug users receiving a prescription for diamorphine in the United Kingdom in 2000, and report on their status in 2002. A retrospective case-note review was conducted in England and Wales. Two hundred and ten (72%; 210/292) patients' sets of case-notes were reviewed at 27 of the 42 (64%) drug clinics where diamorphine was prescribed by the doctor. Patients had been receiving a prescription for diamorphine for a median length of six years. The majority were unemployed white males, with a median age of 44 years. Illicit drug use and criminal activity, while low, had not been eliminated totally. The majority were prescribed ampoules and few had significant health problems. In some cases patients had been transferred to injectable diamorphine from injectable methadone to reduce injection related problems. There were wide variations in dose. The majority of patients had no serious drug, health or social problems. Diamorphine prescribing was a long-term commitment. The experience from the United Kingdom has been one of long-term prescribing with the aim of retaining patients in treatment and reducing the harms caused by illicit drug use. Prospective studies are needed to determine the long-term consequences of receiving a diamorphine prescription.

Multidisciplinary assessment at a child development centre: do we conform to recommended standards?

BACKGROUND

A proposed standard for the multidisciplinary assessment (MDA) of children with autism has been recently published by the National Autistic Society. This prompted a review of current practice at the child development centre in our local centre, to judge whether we were able to conform to the proposed national standard. The recommendation is that a child should complete a three-stage assessment process from referral to completion of assessment within 30 weeks, with set times for completion of each stage (6, 7 and 17 weeks respectively). We applied this assessment model to children with a range of neurodevelopment problems, as the process of MDA is the same, irrespective of diagnosis.

METHODS

A retrospective analysis of medical and therapy records of all MDAs was carried out between April 2001 and March 2002.

RESULTS

In the 12-month period studied, 52 MDAs were performed. Delays occurred, as judged by the standard, at all three stages of the assessment process. A total of 42% of children were seen within 6 weeks of initial referral, 37% within a further 7 weeks for specialist assessment, and 37% within a further 17 weeks for completion of MDA. As delays occurred at all stages, the cumulative total showed that only 19% of children completed all three stages within the recommended 30-week standard. Barriers encountered included waiting times to see professionals, parental non-attendance and prolonged assessment of complex problems. Some of these factors are outside our control, and on removing these factors the data were re-analysed. This resulted in a slight improvement to 45%, 48% and 49% for completion of stages 1, 2 and 3 respectively. The major reason for delay remained the service capacity.

CONCLUSION

In our experience the standards proposed by the National Autistic Society are not practical within present resources. We suggest that a reasonable expectation is to complete all assessments, from first concern to completed MDA, should be carried out within 52 weeks with present levels of resources. Any further improvement will require additional resources to reduce waiting times and increase the capacity.

Boys with high body masses have an increased risk of developing asthma: findings from the National Longitudinal Survey of Youth (NLSY)

OBJECTIVE

To determine the relation between body mass index and the development of asthma in children.

DESIGN

Prospective study of 4393 asthma-free children followed for up to 14 years.

SETTING

Children of participants in the National Longitudinal Survey of Youth.

METHODS

Analysis was limited to children who were followed from birth and were asthma-free during the first 24 months of life. The outcome was the development of asthma during follow-up (incident asthma). Body mass index (BMI) was our main predictor of interest. Survival analyses, using time to development of asthma as the main endpoint, were stratified by sex and controlled for race/ethnicity, poverty status, and prenatal maternal smoking.

RESULTS

Asthma developed in 218 (5.0 %) children during the follow-up period. The relation between BMI and incident asthma varied by sex. A BMI > or =85th percentile at age 2-3 years was a risk factor for subsequent asthma development in boys (hazard ratio (HR) 1.6 95% confidence interval (CI) 1.1, 2.4) but not girls (HR 0.8, 95% CI 0.5, 1.4). Similarly, boys with BMIs always > or =85th percentile were at increased risk for subsequent asthma development (HR 2.4, 95% CI 1.4, 4.4) but not girls (HR 1.5, 95% CI 0.7, 2.9).

CONCLUSION

Boys with high body masses may be at an increased risk for developing asthma.

Human granulocytic ehrlichiosis agent inhibits superoxide anion generation by human neutrophils

The human granulocytic ehrlichiosis (HGE) agent, which replicates in neutrophils, was found not to induce superoxide anion (O(2)(-)) generation or extracellular release by human peripheral blood neutrophils, as measured by a luminol-dependent chemiluminescence assay or a cytochrome c reduction assay, respectively. Furthermore, the HGE agent completely prevented O(2-) release by neutrophils upon stimulation with phorbol myristate acetate (PMA), formylmethionyl-leucyl-phenylalanine, or Escherichia coli. The inhibition was HGE agent dose dependent, required ehrlichial contact with the host cells, and was reversible upon removal of the extracellular HGE agent bound to the host cells prior to PMA stimulation. Structural integrity of or new protein synthesis by the HGE agent was not required for the inhibition; carbohydrate but not surface protein of the HGE agent was required. The HGE agent did not prevent O(2-) generation in human peripheral blood monocytes derived from the same individual. This neutrophil-specific prevention of O(2-) generation by the HGE agent would be critical in survival of the HGE agent. This is the first demonstration of the rapid inhibition of preexisting NADPH oxidase in human neutrophils by the HGE agent.

Analysis of 16S rRNA and 51-kilodalton antigen gene and transmission in mice of Ehrlichia risticii in virgulate trematodes from Elimia livescens snails in Ohio

Operculate snails (the family Pleuroceridae: Elimia livescens) were collected between June and October 1998 from a river in central Ohio where repeated cases of Potomac horse fever (PHF) have occurred. Of collected snails, consistently 50 to 80% carried a combination of cercariae and sporocysts of digenetic virgulate trematodes. The trematodes obtained from each snail were pooled and tested for Ehrlichia risticii, the agent of PHF, by nested PCR using primers specific to the 16S rRNA gene. Out of a total of 209 trematode pools, 50 pools were found to be positive by PCR. The DNA sequence of the 16S rRNA gene identified in one trematode pool was identical to that of the type strain of E. risticii, and the sequence of the gene identified in another pool differed from that of the type strain by 1 nucleotide. Comparison of the deduced amino acid sequence of the partial 51-kDa antigen gene from various sources revealed that Maryland, Ohio (except Ohio 081), and Kentucky strains are in a cluster distinct from the sequences obtained from sources in California and Oregon. Ohio 081 was shown previously by antigenic composition analysis to be distinct from other groups. However, all sequences examined were not segregated according to their sources: horse blood or infected trematodes. E. risticii was found to be transmittable from trematodes to mice and was subsequently passaged from infected mice to additional mice, as determined by PCR analysis. Our findings suggest the evolution of E. risticii in the natural reservoir in separate geographic regions and persistent infection of trematode populations with E. risticii during summer and early fall. The study also suggests that the mouse can be used to isolate E. risticii from the infected trematode.

Intracellular infection by the human granulocytic ehrlichiosis agent inhibits human neutrophil apoptosis

In patients with human granulocytic ehrlichiosis (HGE), the HGE agent has been seen only in the peripheral blood granulocytes, which have a life span too short for ehrlichial proliferation. To determine if the HGE agent delays the apoptosis of human peripheral blood neutrophils for its advantage, peripheral blood granulocytes consisting mostly of neutrophils were incubated with freshly freed host cell-free HGE agent in vitro. The HGE agent induced a significant delay in morphological apoptosis and the cytoplasmic appearance of histone-associated DNA fragments in the granulocytes. This antiapoptotic effect was dose dependent. Although much weaker than the HGE agent freshly freed from the host cells, noninfectious purified HGE agent stored frozen and thawed also had antiapoptotic effect, which was lost with proteinase K treatment but not with periodate treatment. Treatment of neutrophils with a transglutaminase inhibitor, monodansylcadaverine, blocked the antiapoptotic effect of the HGE agent. Addition of oxytetracycline, however, did not prevent or reverse the antiapoptotic effect of the HGE agent. These results suggest that binding of a protein component(s) of the HGE agent to neutrophils and subsequent cross-linking and/or internalization of the receptor and ehrlichiae are required for antiapoptotic signaling, but ehrlichial protein synthesis and/or proliferation is not required. MG-132, a proteasome inhibitor, and cycloheximide accelerated the apoptosis of neutrophils and overrode the antiapoptotic effect of the HGE agent. Studies with specific inhibitors suggest that protein kinase A, NF-kappaB, and interleukin 1beta are not involved in the antiapoptotic mechanism of the HGE agent.

The relation of perceived neighborhood danger to childhood aggression: a test of mediating mechanisms

In the current study, two mediational mechanisms, parenting practices and children's beliefs about aggression, were hypothesized to account for the relationship between perceived neighborhood danger and childhood aggression. Using structural equation modeling, data were analyzed from an inner-city school-based sample of 732 predominantly African American 5th graders. Results suggested that perceived neighborhood danger was associated with strong positive beliefs about aggression, which in turn was associated high levels of aggression. The hypothesized mediating role of parenting practices (restrictive discipline, parental monitoring, and parental involvement) on the relation between perceived neighborhood danger and child aggression was not supported. However, the current findings suggest that children's positive beliefs about aggression mediated the relationship between restrictive discipline and aggression. Directions for future research are discussed.

The application of Poisson random-effects regression models to the analyses of adolescents' current level of smoking

BACKGROUND

In school-based smoking prevention research, it is still debatable whether parents or peers are most influential to maintained smoking among adolescents. As a result, this study examines the effects of parental and peer approval of smoking on adolescents' current levels of smoking.

METHODS

Poisson random-effects regression models were used to assess the effects of parental and peer approval of smoking on adolescents' (n = 913) current level of smoking.

RESULTS

Results of these analyses indicate that a stronger relationship between parental approval of smoking and current level of smoking was found for female adolescents than for male adolescents. Conversely, a stronger relationship between peer approval of smoking and current level of smoking was found for male adolescents than for female adolescents. With respect to race, the influence of parental approval of smoking on adolescents' current level of smoking was generally more pronounced for minority adolescents, relative to white adolescents. However, the influence of peer approval of smoking on current level of smoking was strongest for white adolescents and was less strong for black, Hispanic, and Asian adolescents.

CONCLUSION

The findings of this study demonstrated that the effects of parental and peer approval of smoking on adolescents' current levels of smoking were varied by gender and race. These differential effects may have some implication for the development of future school-based smoking prevention and cessation programs.

Human granulocytic ehrlichiosis agent and Ehrlichia chaffeensis reside in different cytoplasmic compartments in HL-60 cells

The human granulocytic ehrlichiosis (HGE) agent resides and multiplies exclusively in cytoplasmic vacuoles of granulocytes. Double immunofluorescence labeling was used to characterize the nature of the HGE agent replicative inclusions and to compare them with inclusions containing the human monocytic ehrlichia, Ehrlichia chaffeensis, in HL-60 cells. Although both Ehrlichia spp. can coinfect HL-60 cells, they resided in separate inclusions. Inclusions of both Ehrlichia spp. were not labeled with either anti-lysosome-associated membrane protein 1 or anti-CD63. Accumulation of myeloperoxidase-positive granules were seen around HGE agent inclusions but not around E. chaffeensis inclusions. 3-(2, 4-Dinitroanilino)-3'-amino-N-methyldipropylamine and acridine orange were not localized to either inclusion type. Vacuolar-type H+-ATPase was not colocalized with HGE agent inclusions but was weakly colocalized with E. chaffeensis inclusions. E. chaffeensis inclusions were labeled with the transferrin receptor, early endosomal antigen 1, and rab5, but HGE agent inclusions were not. Some HGE agent and E. chaffeensis inclusions colocalized with major histocompatibility complex class I and II antigens. These two inclusions were not labeled for annexins I, II, IV, and VI; alpha-adaptin; clathrin heavy chain; or beta-coatomer protein. Vesicle-associated membrane protein 2 colocalized to both inclusions. The cation-independent mannose 6-phosphate receptor was not colocalized with either inclusion type. Endogenously synthesized sphingomyelin, from C6-NBD-ceramide, was not incorporated into either inclusion type. Brefeldin A did not affect the growth of either Ehrlichia sp. in HL-60 cells. These results suggest that the HGE agent resides in inclusions which are neither early nor late endosomes and does not fuse with lysosomes or Golgi-derived vesicles, while E. chaffeensis resides in an early endosomal compartment which accumulates the transferrin receptor.

Comparison of PCR and culture to the indirect fluorescent-antibody test for diagnosis of Potomac horse fever

Potomac horse fever is an acute systemic equine disease caused by Ehrlichia risticii. Currently, serologic methods are widely used to diagnose this disease. However, serologic methods cannot determine whether the horse is presently infected or has been exposed to ehrlichial antigens in the past. The purpose of the present study was to compare the sensitivities of the nested PCR and cell culture with that of the indirect fluorescent-antibody (IFA) test for the diagnosis of Potomac horse fever. Blood and fecal specimens serially collected from a pony experimentally infected with E. risticii Maryland, blood specimens serially collected from mice inoculated with E. risticii Ohio 380, and blood and/or fecal specimens collected from 27 horses which had clinical signs compatible with Potomac horse fever were examined. These horses resided in Kentucky, Indiana, Pennsylvania, and Vermont. The IFA test titer became positive after 6 days postinoculation (p.i.) for the pony. A culture of the blood of the pony was positive for E. risticii starting on day 1 and was positive through day 28 p.i. By the nested PCR, E. risticii was detectable in the blood and feces of the pony starting on day 1 and was detectable through day 32 p.i. E. risticii was detected in the blood of subclinically infected mice by the nested PCR. Twenty-two clinical specimens were seropositive for E. risticii by the IFA test, with titers ranging from 1:20 to 1:1,280. E. risticii was cultured from 95% (20 of 21) of seropositive clinical blood specimens. E. risticii was detected in the blood by PCR in 81% (17 of 20) of the culture-positive clinical specimens. The study indicated that the nested PCR is as sensitive as culture for detecting infection with E. risticii.

Carotid duplex criteria for a 60% or greater angiographic stenosis: variation according to equipment

PURPOSE

The purpose of this study was to evaluate the carotid duplex criteria for a > or = 60% angiographic internal carotid artery (ICA) stenosis and the degree of variation among duplex scanners.

METHODS

Carotid duplex criteria for a > or = 60% angiographic stenosis were evaluated in two ICAVL-accredited vascular laboratories with different brands of duplex scanners (Siemens-Quantum and Diasonics in Laboratory A, ATL and Diasonics in Laboratory B). Analysis was performed for 360 carotid bifurcations in 180 consecutive patients who had concurrent angiographic and duplex evaluation. Blinded angiogram evaluation was performed with precision electronic calipers on magnified views, with stenosis calculated by criteria of the Asymptomatic Carotid Atherosclerosis Study and the North American Symptomatic Carotid Endarterectomy Trial. Duplex data included internal carotid artery peak systolic velocity (ICA PSV), ICA end-diastolic velocity, and the ratio of ICA PSV to common carotid artery (CCA) PSV (ICA/CCA ratio).

RESULTS

The most accurate determination of a > or = 60% ICA stenosis was obtained with ICA/CCA ratio and ICA PSV, but the optimal threshold differed for all four scanners. The optimal ICA/CCA ratio varied from 2.6 to 3.3, and the optimal ICA PSV varied from 190 to 240 cm/sec. All four scanners produced criteria that give a positive predictive value > 90% while maintaining accuracy at > or = 90%. Logarithmic transformation of duplex variables created a linear relationship between duplex values and angiographic stenosis, allowing statistical evaluation of scanner operating characteristics by linear regression analysis and analysis of covariance. This analysis revealed that the mathematic equation relating duplex values with angiographic percent stenosis was statistically different for one of the four scanners (p < 0.05). Scanner differences did not appear to be due to technologists, because the regression lines were nearly identical for the two Diasonics scanners despite use by different technologists. Ignoring the significant difference in operating characteristics for one of the four scanners would result in a mean error for predicting a 60% stenosis of 14% to 18% (equating a 46% or 78% stenosis with a 60% stenosis).

CONCLUSIONS

We conclude that the correlation of duplex data with angiographic percent stenosis and the duplex criteria for a > or = 60% stenosis are machine-specific. Regression analysis can determine whether apparent differences are due to chance or significant differences in scanner characteristics. Future studies should include regression analysis according to equipment type.

Evidence for a high rate of false-positive results with the indirect fluorescent antibody test for Ehrlichia risticii antibody in horses

OBJECTIVE

The original objective was to determine seroprevalence of Ehrlichia risticii antibody among horses in California. On the basis of the unexpected results of the survey, an investigation into the accuracy and reproducibility of results of the indirect fluorescent antibody (IFA) test for E risticii was carried out.

DESIGN

Prospective, seroprevalence study.

ANIMALS

Healthy horses (n = 655) and horses with clinical signs of equine monocytic ehrlichiosis (EME; n = 514) from various regions of California.

PROCEDURE

The IFA test was performed. Results were compared with results of an ELISA and with results of western immunoblot analysis.

RESULTS

Overall, 104 of 655 (15.9%) healthy horses had evidence of an antibody response. However, 84 of 514 (16.3%) horses with clinical signs of EME also had positive test results, and of the 8 seropositive diseased horses for which paired (acute and convalescent) samples had been submitted, only 1 had a rise in antibody titers between the acute and convalescent samples. Comparison of results for the IFA test, ELISA, and western immunoblot analysis revealed a high rate of false-positive results for the IFA test. Subsequent studies suggested that routine vaccination of horses with non-E risticii vaccines may have contributed to the false-positive reactions.

CLINICAL IMPLICATIONS

The data failed to provide conclusive evidence of E risticii infection among California horses. Owing to the high percentage of false-positive test results, caution is advised when using the IFA test to diagnose EME in horses or to determine the necessity for E risticii vaccination.

Ehrlichia muris sp. nov., identified on the basis of 16S rRNA base sequences and serological, morphological, and biological characteristics

The 16S rRNA gene of a new infectious agent, strain AS145T (T = type strain), which was isolated from a wild mouse in Japan, was amplified by using the PCR. The amplimers were directly sequenced by dideoxynucleotide methods with Taq DNA polymerase. Sequence comparisons with other members of the tribe Ehrlichieae and related species revealed that the infectious agent isolated from the mouse is a new species of the genus Ehrlichia that is most closely related to Ehrlichia chaffeensis (level of sequence similarity, 97.9%), an agent of human ehrlichiosis in the United States. This result was consistent with the results of an immunoblot analysis performed with immune sera against different ehrlichiosis agents. On the basis of these findings and other morphological, biological, and serological characteristics of the organism, we propose that ehrlichiae with these properties belong to a new species, Ehrlichia muris.

C-reactive protein and alpha 1-acid glycoprotein levels in dogs infected with Ehrlichia canis

To elucidate whether acute-phase protein responses occur in dogs infected with Ehrlichia canis, C-reactive protein (CRP) and alpha 1-acid glycoprotein (AAG) levels were serially measured in the plasma of five dogs experimentally inoculated with E. canis and 10 sham-inoculated or noninoculated control dogs. The CRP concentration was measured by a canine-specific capture enzyme-linked immunosorbent assay, and the AAG concentration was measured by a canine-specific radial immunodiffusion method. In all E. canis-inoculated dogs, a 3.3- to 6.5-fold increase in the plasma CRP concentration and a 1.9- to 8.6-fold increase in the plasma AAG concentration over the preinoculation level occurred at days 4 to 6 postexposure. Despite the persistence of E. canis and high antibody titers, both CRP and AAG concentrations gradually declined to preexposure levels by day 34 postexposure. E. canis-infected dogs had mild and transient clinical signs which resolved without treatment by day 14 postexposure. The CRP and AAG concentrations in control inoculated or nontreated dogs remained within the normal range throughout the experimental period. Of 12 dogs naturally infected with E. canis, 75% had greater than 50 micrograms of CRP per ml and 83% had greater than 500 micrograms of AAG per ml. All of these 12 dogs had chronic and severe clinical signs of canine ehrlichiosis. Thus, elevations in the levels of acute-phase proteins occur in both acute and chronic canine ehrlichiosis. Determination of CRP and AAG concentrations may help in assessing the severity of inflammatory damage in dogs with E. canis infections.

A comparison of doctors' practice in notifying addicts to the Home Office and reporting them to the North Western Drug Misuse Database

Doctors have been required to notify named addict patients to the Chief Medical Officer at the Home Office since 1968, and since 1990 have been encouraged to report voluntarily all their drug misusing patients to anonymized NHS regional databases. The North Western Drug Misuse Database, set-up for research purposes in 1985, was the forerunner of these databases. Compliance by doctors from three North Western District Health Authorities with both data collection systems between 1986 and 1989 was assessed by matching the names of notified addicts with the attributors of individuals reported to the NWDMD as users of notifiable drugs. By 1989 72% of addicts notified were also reported to the NWDMD although doctors working in hospital general departments still tended only to notify them. There was no evidence that particular general practitioners consistently did not notify their addict patients while reporting them to the NWDMD. The findings suggest that it will take some time for doctors to become accustomed to reporting all their drug misusing patients to the regional databases as well as notifying to Home Office those who met the notification criteria.

Effects of neuroleptics on glutaminase from rat synaptosomes

Phosphate-activated glutaminase was isolated from synaptosomes from three areas of rat brain. Glutamine utilization phosphate activation and inhibition by glutamate or ammonia were assessed in the absence or presence of haloperidol, chlorpromazine, or clozapine. All three drugs (at 1 micromolar concentration) elevated the Km for glutamine using preparations from the amygdala, hippocampus, or striatum. They interfered with phosphate activation only in the amygdala preparation. No drug affected end-product inhibition. The data suggest that neuroleptics may depress the release of glutamic acid from synaptosomes by interfering with the activation of glutaminase by phosphate.

A biochemical basis for psychotic symptoms in patients with brain dysfunction

Thirteen brain dysfunctional patients with psychosis were compared to 11 brain dysfunctional patients without psychosis by EEG, CT scan and neuropsychological test abnormalities, and abnormalities in serine metabolism. None of the tests of conventional measures of brain pathology and pathophysiology significantly differentiated between the psychotic and nonpsychotic patients; only the last measure which has previously been shown to be a biochemical vulnerability factor for psychosis, was significantly different in the two groups. This study suggests that the brain pathology and pathophysiology per se are not significant factors that make such patients psychotic, but these patients are vulnerable to psychosis because of a biochemical abnormality.

Effects of glutaminase inhibition on release of endogenous glutamic acid

The effects of four inhibitors of glutamine hydrolysis on synaptosomes derived from several regions of the brain were studied. The calcium-specific release of endogenous glutamic acid was determined in the presence of varying concentrations of 6-diazo-5-oxo-norleucine (DON), N-ethyl-maleimide (NEM), 2-chloroadenosine (2-CA) or haloperidol. Both DON and NEM reduced the calcium-specific release in a concentration-dependent manner, equally in all regions tested. 2-Chloroadenosine also decreased release and the effect was most evident in the amygdala. As reported earlier, haloperidol blocked release of glutamic acid only in the amygdala. In synaptosomes from the amygdala, both DON and NEM failed to affect the calcium-specific release of aminobutyric acid (GABA), glycine or serotonin at concentrations which reduced release of glutamate by 50%; NEM, but not DON, elevated the release of dopamine. Dopamine itself affected neither the release of glutamate nor its blockade by haloperidol even in extremely large concentrations.

Drug effects on serine metabolism in psychiatric patients

The question of whether neuroleptics can play a role in the hyperserinemia and low serine hydroxymethyltransferase (SHMT) activity previously reported in psychotic patients is investigated in this report. We find that in drug-free psychotics who had significantly higher plasma serine levels (PSL) and lower SHMT activity compared to nonpsychotics and normal subjects, more than 2 weeks of neuroleptic treatment decreased PSL and did not affect SHMT activity. This finding makes it unlikely that neuroleptics play an important role in the hyperserinemia of psychotics. The possible role of dietary factors in these patients is also discussed.

Differentiation of psychotic from nonpsychotic depression by a biological marker

In a study of fasting plasma serine levels (PSL) previously shown to be a biological marker for psychosis, we found significantly higher (P = 0.0008) PSL in 18 psychotic depressives when compared to 22 nonpsychotic depressives. Similarly the activity of the enzyme serine hydroxymethyltransferase (SHMT) which cleaves serine to glycine, was significantly lower (P less than 0.0001) in psychotics than in nonpsychotics. The difference between psychotic and nonpsychotic depressives were not attributable to age, sex or drug intake. This finding is in support of the hypothesis that these two types of depressions are qualitatively distinct from each other.

Amphetamine stimulation of glutaminase is blocked by neuroleptics

The ability of several classes of neuroleptics to inhibit the activity of phosphate-activated glutaminase was studied in several brain regions. These agents decreased glutaminase activity only in the amygdala. Amphetamine elevated glutaminase activity in this region. This stimulation was not blocked by (-) butaclamol, but was blocked by (+) butaclamol, haloperidol, chlorpromazine or clozapine.

Speech perception ability and psychophysical tuning curves in hearing-impaired listeners

Performance-intensity functions for monosyllabic words were obtained as a function of signal-to-noise ratio for broadband and low-pass filtered noise. Subjects were 11 normal-hearing listeners and 13 hearing-impaired listeners with flat, moderate sensorineural hearing losses and good speech-discrimination ability (at least 86%) in quiet. In the broadband-noise condition, only small differences in speech perception were noted between the two groups. In low-pass noise, however, large differences in performance were observed. These findings were correlated with various aspects of psychophysical tuning curves (PTCs) obtained from the same individuals. Results of a multivariate analysis suggest that performance in broadband noise is correlated with filter bandwidth (Q10), while performance in low-pass noise is correlated with changes on the low-frequency side of the PTC.

Metabolism of an ingested serine load in psychotic and nonpsychotic subjects

Our previous studies have shown that in psychotics, the plasma serine level is abnormally high and that plasma serine hydroxymethyltransferase (which cleaves serine to glycine) activity is abnormally low as compared with that in nonpsychotic subjects. In this study, psychotic and nonpsychotic subjects ingested a large bolus of L-serine (4 mM/kg) at breakfast and blood was drawn before breakfast, 2 hr, 4 hr, and 6 hr after serine ingestion. Baseline serine and SHMT activity differentiated between psychotics and nonpsychotics with high degrees of significance (p less than 0.0001) and p less than 0.01, respectively). Plasma serine levels 2 hr after serine ingestion were significantly higher (p less than 0.01) in nonpsychotics as compared with psychotics. Elimination of serine in psychotics was bimodal and was significantly different from that of nonpsychotics (p less than 0.0079, Moses test). These findings provide additional evidence for abnormal serine metabolism in psychotic patients.

Direct effect of neuroleptics on glutamate release

In studies designed to assess the pre-synaptic effects of neuroleptics in vitro, synaptosomes were prepared from several regions of rat brain. These preparations were incubated in the presence of a representative of each of the major classes of neuroleptic--chlorpromazine, haloperidol, or clozapine, or with (+) or (-)butaclamol. The calcium-specific release of endogenous glutamic acid was reduced only in synaptosomes derived from the amygdala. In this area, each of these agents [except (-)butaclamol] reduced the release of glutamic acid to a maximum of 40% in a concentration-dependent manner. When [3H]glutamine was included in the incubation media, a reduction in the released [3H]glutamate was present with 10(-8) M haloperidol, and 5 X 10(-8) M (+)butaclamol, clozapine, or chlorpromazine. (-)Butaclamol was inactive at 10(-5) M, a concentration producing complete blockade of the release of [3H]glutamic acid when active agents were included. Again, the effects were observed only in the amygdala. All agents, including (-)butaclamol blocked the uptake of [3H]glutamine into depolarized synaptosomes.

Serine metabolism and psychosis

Plasma serine levels (PSL) in a group of patients with the diagnosis of major or atypical psychoses were significantly higher than in patients with nonpsychotic diagnoses or nonpatient controls. The enzyme serine hydroxymethyltransferase (SHMT), which metabolizes serine to glycine, showed abnormal activity in the psychotics compared to nonpsychotics and controls. PSL differentiated psychotics from nonpsychotics with a high (95%) degree of confidence. PSL were highly correlated to SHMT activity, suggesting that the hyperserinemia in psychotics was due to the abnormality of the enzyme. Previously psychotic patients who had been treated and were psychosis free still manifested abnormal high PSL and abnormal enzyme activity. These findings suggest that disturbed serine metabolism may be a biological marker and a vulnerability factor for psychosis.

Potential locus and mechanism of blockade of conditioned avoidance responding by neuroleptics

In order to assess the possible loci of action of neuroleptics in blocking the acquisition of a one-way conditioned avoidance response, microinjections of three neuroleptics and seven putative neurotransmitters were made into several brain regions and their effects on this behavior were assessed. When injected into the amygdala, the ED50 values for haloperidol (0.128 nmol), chlorpromazine (1.04 nmol) and thioridazine (1.41 nmol) were appropriate in relation to their clinical potency. Injections of neurotransmitters were without effect except in a few cases. Most significantly, the intra-amygdaloid administration of glutamate diethyl ester (an antagonist at quisqualate-type receptors) produced a blockade of avoidance acquisition which, as in the case of the neuroleptics, was not diminished by pretreatment with atropine. Following intraperitoneal injection of chlorpromazine, a statistically-significant blockade of avoidance acquisition and of glutamate, released from slices of amygdala, was obtained at doses of 2 mg/kg or more. With haloperidol, comparable behavioral effects and release of glutamate were found at doses of 0.05 mg/kg or more. The depression of release of glutamate from amygdaloid slices could be attributed to glutamate derived from glutamine. These data suggest a possible role for glutamatergic transmission in the effects of neuroleptics.

RDS-127 (2-di-n-propylamino-4,7-dimethoxyindane): central effects of a new dopamine receptor agonist

Apomorphine (APO), 2-di-n-propylamino-4,7-dimethoxyindane (RDS-127) and 2-di-n-propylamino-5,8-dimethoxytetralin (JMC-181) were examined on a variety of biochemical and pharmacological assays to determine their possible interaction with dopamine (DA) receptors. Nanomolar concentrations of all three compounds displaced [3H]APO from specific high-affinity binding sites in rat striatal membrane preparations, while higher concentrations were required to displace [3H]spiperone or [3H]rauwolscine. APO caused a concentration-dependent increase in the ability to stimulate postsynaptic DA receptors associated with adenylate cyclase (D1-sites) in the carp retina, whereas RDS-127 or JMC-181 were inactive in concentrations up to 300 microM. APO was very active in causing contralateral turning behavior in rats with a 6-hydroxydopamine lesioned substantia nigra (SN); RDS-127 was approximately 8 times less potent in producing contralateral rotations and JMC-181 was inactive. RDS-127 produced biphasic, dose-related changes in rat spontaneous locomotor activity similar to that reported for APO. The locomotor stimulant effects of RDS-127 were 3 times more potent and 4 times greater in duration than that induced by APO. JMC-181 produced primarily sedation in the doses tested. APO, RDS-127 and JMC-181 were active in inhibiting the accumulation of dopa in the caudate nucleus and olfactory tubercle using the in vivo gamma-butyrolactone procedure; 5-hydroxytryptophan accumulations were not altered significantly. RDS-127 was 7 times more potent than APO in inhibiting dopa accumulation in the caudate nucleus and equipotent to APO in the olfactory tubercle. Dopa accumulation was weakly inhibited by JMC-181. When single unit extracellular action potentials were recorded from purported DA-containing neurons in the SN, RDS-127 decreased the firing of neurons in the pars compacta of SN (ID100 = 40 +/- 10 nmol/kg i.v.). In contrast, firing of units in the pars reticulata of SN were not altered or increased in response to RDS-127. The biochemical electrophysiological and behavioral effects of RDS-127 were blocked or reversed by DA receptor antagonists. These data indicate that RDS-127 is significantly more selective than APO in preferentially activating DA autoreceptors as opposed to the postsynaptic DA receptors in the nigrostriatal pathway. The possibilities of designing potent, long acting, nonergot, noncatechol-containing DA receptor agonists are discussed.