World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of ectoparasiticides against biting and nuisance flies on ruminants

These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of ectoparasiticides (excluding repellents) against the biting and nuisance dipteran flies of ruminants. Information is provided on the selection of animals, dose determination and dose confirmation studies, field studies, record keeping and result interpretation. These guidelines advocate the use of pen facilities for dose determination and dose confirmation studies. These guidelines also are intended to assist investigators on how to conduct specific studies, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the worldwide adoption of standard procedures.

Vagus nerve stimulation for epilepsy: randomized comparison of three stimulation paradigms

Vagus nerve stimulation (VNS) is an effective adjunctive treatment for intractable epilepsy. However, the optimal range of device duty-cycles [on/(on + off times)] is poorly understood. The authors performed a multicenter, randomized trial of three unique modes of VNS, which varied primarily by duty-cycle. The results indicate that the three duty-cycles were equally effective. The data support the use of standard duty-cycles as initial therapy.

An initial investigation of spinal mechanisms underlying pain enhancement induced by fractalkine, a neuronally released chemokine

Fractalkine is a chemokine that is tethered to the extracellular surface of neurons. Fractalkine can be released, forming a diffusible signal. Spinal fractalkine (CX3CL1) is expressed by sensory afferents and intrinsic neurons, whereas its receptor (CX3CR1) is predominantly expressed by microglia. Pain enhancement occurs in response both to intrathecally administered fractalkine and to spinal fractalkine endogenously released by peripheral neuropathy. The present experiments examine whether fractalkine-induced pain enhancement is altered by a microglial inhibitor (minocycline) and/or by antagonists/inhibitors of three putative glial products implicated in pain enhancement: interleukin-1 (IL1), interleukin-6 (IL6) and nitric oxide (NO). In addition, it extends a prior study that demonstrated that intrathecal fractalkine-induced mechanical allodynia is blocked by a neutralizing antibody to the rat fractalkine receptor, CX3CR1. Here, intrathecal anti-CX3CR1 also blocked fractalkine-induced thermal hyperalgesia. Furthermore, blockade of microglial activation with minocycline prevented both fractalkine-induced mechanical allodynia (von Frey test) and thermal hyperalgesia (Hargreaves test). Microglial activation appears to lead to the release of IL1, given that pretreatment with IL1 receptor antagonist blocked both fractalkine-induced mechanical allodynia and thermal hyperalgesia. IL1 is not the only proinflammatory cytokine implicated, as a neutralizing antibody to rat IL6 also blocked fractalkine-induced pain facilitation. Lastly, NO appears to be importantly involved, as l-NAME, a broad-spectrum NO synthase inhibitor, also blocked fractalkine-induced effects. Taken together, these data support that neuronally released fractalkine enhances pain via activation of spinal cord glia. Thus, fractalkine may be a neuron-to-glia signal triggering pain facilitation.

Outcome of fetal pyelectasis diagnosed antenatally

Renal pelvis dilatation is a common anomaly detected at the 20-week anomaly scan. The aim of this study was to evaluate the postnatal outcome of fetal pyelectasis in an unselected obstetric population. This was a retrospective study of fetal pyelectasis detected at midtrimester anomaly scan. Fetal pyelectasis was classified as mild if the anteroposterior renal pelvis diameter measured >5 mm-< or= 7 mm, moderate >7-< or = 10 mm and severe as >10 mm. Persistant fetal pyelectasis was defined as >7 mm in the third trimester.

RESULTS

During the study period fetal pyelectasis was identified in 74 women. 6 were excluded, as case records were not available. Mild pyelectasis was identified in 38/67(56.7%), moderate pyelectasis in 20/67(29.8%) and severe pyelectasis in 9/67(13.4%). None of the infants in the mild pyelectasis subgroup required surgery. 3/29(10%) in the moderate and severe pyelectasis subgroup required postnatal surgery. Of the 38 with mild fetal pyelectasis 13.1% had a positive postnatal diagnosis out of which 7.9% had vesico-ureteric reflux, 2.6% renal dysplasia and 2.6% pelvi-ureteric junction (PUJ) stenoses.

CONCLUSION

74% of pregnancies in the mild pyelectasis subgroup demonstrated spontaneous resolution. However persistent mild pyelectasis may lead to postnatal morbidity and should be followed up.

The collaborative lipid research clinics program family study: Detection of major genes influencing lipid levels by examination of heterogeneity of familial variances

Age, sex-adjusted, and transformed lipid and lipoprotein data on over 1,200 white North American sibships in the Collaborative Lipid Research Clinics Family Study were analyzed for possible major genes causing high or low levels of these traits. The sibships were stratified on the basis of parents' trait values, and within-sibship variance in the high (or low) families was compared to that in the normal families via an F-test. The null hypothesis of multifactorial transmission was strongly rejected for low LDL, low total cholesterol, and high HDL families. An analysis of spouse-pair variance gave similar results. This may reflect the presence of dominant genes for hyperalpha- and hypobetalipoproteinemia. There was weaker evidence for single genes causing hyperbetalipoproteinemia. There was no evidence for major genes influencing triglyceride levels. Methodological issues with significant bearing on these results and those of other studies are discussed.

Measurement of the Michel parameter rho in muon decay

The TWIST Collaboration has measured the Michel parameter rho in normal muon decay, mu(+)--> e(+)nu(e)nu (mu). In the standard model, rho = 3/4. Deviations from this value imply mixing of left- and right-handed muon and electron couplings. We find rho=0.750 80+/-0.000 32(stat) +/- 0.000 97(syst) +/- 0.000 23, where the last uncertainty represents the dependence of rho on the Michel parameter eta. This result sets new limits on the W(L)-W(R) mixing angle in left-right symmetric models.

Evidence that exogenous and endogenous fractalkine can induce spinal nociceptive facilitation in rats

Recent evidence suggests that spinal cord glia can contribute to enhanced nociceptive responses. However, the signals that cause glial activation are unknown. Fractalkine (CX3C ligand-1; CX3CL1) is a unique chemokine expressed on the extracellular surface of spinal neurons and spinal sensory afferents. In the dorsal spinal cord, fractalkine receptors are primarily expressed by microglia. As fractalkine can be released from neurons upon strong activation, it has previously been suggested to be a neuron-to-glial signal that induces glial activation. The present series of experiments provide an initial investigation of the spinal pain modulatory effects of fractalkine. Intrathecal fractalkine produced dose-dependent mechanical allodynia and thermal hyperalgesia. In addition, a single injection of fractalkine receptor antagonist (neutralizing antibody against rat CX3C receptor-1; CX3CR1) delayed the development of mechanical allodynia and/or thermal hyperalgesia in two neuropathic pain models: chronic constriction injury (CCI) and sciatic inflammatory neuropathy. Intriguingly, anti-CX3CR1 reduced nociceptive responses when administered 5-7 days after CCI, suggesting that prolonged release of fractalkine may contribute to the maintenance of neuropathic pain. Taken together, these initial investigations of spinal fractalkine effects suggest that exogenous and endogenous fractalkine are involved in spinal sensitization, including that induced by peripheral neuropathy.

Reducing call-to-needle times: the critical role of pre-hospital thrombolysis

BACKGROUND

Current guidelines recommend that patients with acute myocardial infarction should receive thrombolysis within 60 min of seeking professional help.

AIM

To compare current rates of pre-hospital thrombolysis in Grampian with historical data, and assess the effect of pre-hospital thrombolysis on the proportion of patients achieving 'call-to-needle' times within national guidelines.

DESIGN

Prospective audit.

METHODS

Data were collected on all patients (n=535) admitted to the coronary care unit and thrombolysed, either in hospital or in the community from July 2000 to June 2002, using standardized forms.

RESULTS

One hundred and thirty-three patients (25%) received pre-hospital thrombolysis and 402 (75%) received in-hospital thrombolysis. This compares with a 19% (195/1046) pre-hospital thrombolysis rate in the mid-1990s (p=0.005). Median 'call-to-needle' times were 45 min for pre-hospital thrombolysis and 105 min for patients who received in-hospital thrombolysis (p < 0.001). Only 24% (96/396) of patients receiving in-hospital thrombolysis were treated within the recommended guideline, vs. 79% (88/111) of pre-hospital thrombolysis patients (p <0.001).

DISCUSSION

Pre-hospital thrombolysis rates in Grampian are increasing. Administration of thrombolysis in the community greatly increases the proportion of patients achieving a 'call-to-needle' time of 60 min, with a median time saving of approximately 1 h.

Comparative analyses of multi-species sequences from targeted genomic regions

The systematic comparison of genomic sequences from different organisms represents a central focus of contemporary genome analysis. Comparative analyses of vertebrate sequences can identify coding and conserved non-coding regions, including regulatory elements, and provide insight into the forces that have rendered modern-day genomes. As a complement to whole-genome sequencing efforts, we are sequencing and comparing targeted genomic regions in multiple, evolutionarily diverse vertebrates. Here we report the generation and analysis of over 12 megabases (Mb) of sequence from 12 species, all derived from the genomic region orthologous to a segment of about 1.8 Mb on human chromosome 7 containing ten genes, including the gene mutated in cystic fibrosis. These sequences show conservation reflecting both functional constraints and the neutral mutational events that shaped this genomic region. In particular, we identify substantial numbers of conserved non-coding segments beyond those previously identified experimentally, most of which are not detectable by pair-wise sequence comparisons alone. Analysis of transposable element insertions highlights the variation in genome dynamics among these species and confirms the placement of rodents as a sister group to the primates.

Possible benefit of intravenous immunoglobulin therapy in a lung transplant recipient with West Nile virus encephalitis

During the summer of 2000, a countrywide epidemic of West Nile fever (WNF) occurred in Israel, with 417 confirmed cases and 35 deaths. Immunosuppressed patients had a 31% case-fatality rate, which was significantly higher compared to non-immunosuppressed patients (13%). We describe a 42-year-old male lung-transplant recipient with serologically confirmed West Nile virus (WNV) encephalitis and deteriorating level of consciousness. He was treated with 0.4 g/kg intravenous immunoglobulin preparation from Israeli donors that contained a high titer of anti-WNV antibodies (1 : 1600). The patient showed rapid improvement within 24 h and complete disappearance of signs and symptoms within 48 h. This is the second case of an immunosuppressed patient responding to the same preparation of intravenous immunoglobulins. Larger studies are required in order to establish the therapeutic role of immunoglobulins in patients with WNF.

Docosahexaenoic acid sources for the developing brain during intrauterine life

Docosahexaenoic acid (DHA, 22: 6n-3) and arachidonic acid (AA, 20: 4n-6) provision to the developing fetus, with emphasis towards brain and vascular system growth, is a subject of increasing concern particularly under pathological conditions associated with premature birth or in utero growth restriction following obstruction of the maternal-fetal blood flow. Most of DHA, but also AA accretion under physiological conditions, is maternally dependent and requires adequate maternal nutrition and normally functioning placental-fetal circulation. It has been demonstrated that unlike other fatty acids (FA), DHA is preferentially transported across the placenta into the fetal circulation. The selective transplacental DHA transfer is probably mediated by specific carrier proteins. While some of the latter may be acting in fetal organs, the mechanism(s) for the selective accumulation of DHA in brain is still unknown. The fetal brain and also the fetal liver are capable of producing DHA from linolenic (LnA, 18:3 n-3) acid. How effective this local elongation-desaturation mechanism for DHA provision is and to what degree this route is activated in premature births is not clear. Transfer of DHA via the fetal gastrointestinal tract is an additional route to provide DHA to other fetal organs. As indicated by animal model studies, it holds the potential for DHA supply when the maternal pathway is compromised.

Why clinicians often disagree about the validity of test results

Examining the validity of test results using specialised methods is still a relatively new venture and many different approaches are taken to the same task. This paper discusses some of the reasons why discrepant results and differing conclusions may be arrived at by clinicians or researchers, depending on their theoretical and practical choices. These choices include whether to test for effort, what methods to use, how to employ effort tests, what failure criteria to apply and how to interpret individual results. Equally important is the decision about whether or not to employ effort testing to remove error from data in group research studies. No concensus has yet been reached on the need for systematic effort testing in group studies but there are indications that it should be a serious consideration because controlling for invalid data can lead to altered conclusions.

Effects of injury severity and cognitive exaggeration on olfactory deficits in head injury compensation claims

The purpose of this study was to examine the relationship between exaggeration and scores on a test of olfactory discrimination in patients being assessed in connection with a claim for financial benefits. Participants were 448 patients referred to a private practice in Edmonton, Alberta, Canada for psychological or neuropsychological assessment, related to evaluation of impairment and disability resulting from a work-related or non-work related accident. All patients were involved in some form of compensation claim at the time of their evaluation. All patients completed two tests designed to detect exaggerated cognitive deficits, the Computerized Assessment of Response Bias (CARB) and the Word Memory Test (WMT) as part of their evaluation. The diagnostic groups included 322 head injury cases, varying from very minor to very severe. Normative data for the smell test were derived from 126 patients with orthopedic injuries who passed both the CARB and the WMT. Patients with more severe traumatic brain injuries were 10-12 times more likely to have olfactory deficits than persons with trivial to mild head injuries. In a subgroup of patients who failed either the CARB or the WMT, there was no relationship between injury severity and total scores on the smell test. Therefore, the dose-response relationship between brain injury severity and olfactory deficits is severely attenuated when patients who are probably exaggerating their cognitive deficits are included in the analyses. Those patients with trivial to mild head injuries who demonstrated adequate effort on both the CARB and the WMT were no more likely to show olfactory deficits than the non-head-injured orthopedic control subjects. Therefore, anosmia following mild traumatic brain injury should not be concluded from self-reports or from tests of smell unless tests of effort have been passed. Effort should also be controlled in group studies of olfaction.

Base rates of WAIS-R VIQ-PIQ differences in 1593 psychiatric inpatients

The purpose of this study was to provide the psychologist with base-rate tables for the Wechsler Adult Intelligence Scale-Revised (WAIS-R) Verbal IQ-Performance IQ difference scores in 1593 psychiatric inpatients. Subtables also were provided for each of three primary psychiatric diagnoses (schizophrenia spectrum disorders, bipolar disorders, and depression). The base rates of VIQ-PIQ splits in the full inpatient sample, and those for the subsamples based on primary psychiatric diagnosis, were very similar to those reported in the WAIS-R standardization sample. Consistent with past research on the standardization sample, the VIQ-PIQ split was correlated positively with Full Scale IQ (FSIQ), indicating that larger splits are more common at the higher IQ levels. Therefore, base-rate tables also were provided for the total inpatient sample split into five IQ groupings.

Effort has a greater effect on test scores than severe brain injury in compensation claimants

Nine-hundred and four consecutive patients, including 80 neurological patients and 470 with head injuries, were given neuropsychological tests. All 43 test scores were converted to normative Z-scores and averaged, giving an Overall Test Battery Mean (OTBM). A variable measuring effort correlated 0.73 with the OTBM. The OTBM mean score was 1.20 SD lower in those who failed the Word Memory Test (WMT) than in those who passed the WMT. Sub-optimal effort suppressed the OTBM 4.5 times more than did moderate-severe brain injury. When only those making a good effort were included, patients with severe brain injuries and neurological diseases scored significantly lower than groups presumed to have no neurological impairment, but these group differences were not seen when all cases were analysed together. These data illustrate the importance of measuring and controlling for sub-optimal effort in individual neuropsychological evaluations, as well as in empirical research with similar groups of patients.

Validation of the computerized assessment of response bias in litigating patients with head injuries

The detection of malingering in neuropsychological assessment requires valid measures of incomplete effort. The Computerized Assessment of Response Bias (CARB) is a digit-recognition procedure designed to detect poor effort during a neuropsychological evaluation. We examined the CARB performance of a consecutive series of litigating patients (N = 119) with a full range of head-injury severity, from trivial to severe. Patients with trivial or mild head injuries performed more poorly than did patients with frank brain injuries. Specifically, patients with moderate to severe traumatic brain injuries obtained higher total scores and demonstrated briefer response latencies than did patients with trivial or mild head injuries.