Pharmacokinetics of cefquinome in healthy and Pasteurella multocida-infected rabbits

The pharmacokinetics of cefquinome were studied in healthy and Pasteurella multocida-infected rabbits after a single intramuscular (IM) injection at 2 mg/kg of its sulfate salt. Twelve female New Zealand white rabbits (2.0-2.5 kg) were used; six of them served as controls, and the other six had been infected with P. multocida; the experiments were conducted 1-2 days after nasal inoculation of P. multocida when rabbits showed the signs of respiratory infection. Plasma concentrations of cefquinome were determined using high-performance liquid chromatography. The values of elimination half-life, area under the curve, area under the first moment curve, and mean residence time were significantly lower in infected rabbits (0.48 hr, 4.54 hr*μg/ml, 3.63 hr* hr*μg/ml and 0.8 hr, respectively) than healthy rabbits (0.72 hr, 9.11 hr*μg/ml, 9.85 hr* hr*μg/ml and 1.1 hr, respectively), whereas total body clearance was significantly higher in infected than healthy rabbits. Therefore, P. multocida infection caused significant changes in some of the pharmacokinetic parameters of cefquinome in rabbits. These pharmacokinetic changes may affect dose regimen when used in P. multocida-infected rabbits.

Meta-analysis of the association between suicidal ideation and later suicide among patients with either a schizophrenia spectrum psychosis or a mood disorder

OBJECTIVE

Recent studies of patients with a mix of psychiatric diagnoses have suggested a modest or weak association between suicidal ideation and later suicide. The aim of this study was to examine the extent to which the association between expressed suicidal ideation and later suicide varies according to psychiatric diagnosis.

METHOD

A systematic meta-analysis of studies that report the association between suicidal ideation and later suicide in patients with 'mood disorders', defined to include major depression, dysthymia and bipolar disorder, or 'schizophrenia spectrum psychosis', defined to include schizophrenia, schizophreniform disorder and delusional disorder.

RESULTS

Suicidal ideation was strongly associated with suicide among patients with schizophrenia spectrum psychosis [14 studies reporting on 567 suicides, OR = 6.49, 95% confidence interval (CI) 3.82-11.02]. The association between suicidal ideation and suicide among patients with mood disorders (11 studies reporting on 860 suicides, OR = 1.49, 95% CI 0.92-2.42) was not significant. Diagnostic group made a significant contribution to between-study heterogeneity (Q-value = 16.2, df = 1, P < 0.001) indicating a significant difference in the strength of the associations between suicidal ideation and suicide between the two diagnostic groups. Meta-regression and multiple meta-regression suggested that methodological issues in the primary research did not explain the findings. Suicidal ideation was weakly but significantly associated with suicide among studies of patients with mood disorders over periods of follow-up of <10 years.

CONCLUSION

Although our findings suggest that the association between suicidal ideation and later suicide is stronger in schizophrenia spectrum psychosis than in mood disorders this result should be interpreted cautiously due to the high degree of between-study heterogeneity and because studies that used stronger methods of reporting had a weaker association between suicidal ideation and suicide.

Rare autosomal copy number variations in early-onset familial Alzheimer's disease

Over 200 rare and fully penetrant pathogenic mutations in amyloid precursor protein (APP), presenilin 1 and 2 (PSEN1 and PSEN2) cause a subset of early-onset familial Alzheimer's disease (EO-FAD). Of these, 21 cases of EO-FAD families carrying unique APP locus duplications remain the only pathogenic copy number variations (CNVs) identified to date in Alzheimer's disease (AD). Using high-density DNA microarrays, we performed a comprehensive genome-wide analysis for the presence of rare CNVs in 261 EO-FAD and early/mixed-onset pedigrees. Our analysis revealed 10 novel private CNVs in 10 EO-FAD families overlapping a set of genes that includes: A2BP1, ABAT, CDH2, CRMP1, DMRT1, EPHA5, EPHA6, ERMP1, EVC, EVC2, FLJ35024 and VLDLR. In addition, CNVs encompassing two known frontotemporal dementia genes, CHMP2B and MAPT were found. To our knowledge, this is the first study reporting rare gene-rich CNVs in EO-FAD and early/mixed-onset AD that are likely to underlie pathogenicity in familial AD and perhaps related dementias.

Myocardial toxicity in a group of greyhounds administered ractopamine

Ractopamine, a synthetic β(2)-adrenoceptor agonist, is widely used as a feed additive in the United States to promote a reduction in body fat and enhance muscle growth in cattle, pigs, and turkeys. It has the potential for illegal use in show and racing animals because it may affect performance via its β-adrenergic agonist properties or anabolic activities. Nine greyhounds were orally administered 1 mg/kg of ractopamine to investigate the ability to detect the drug in urine. Postdosing, 7 of 9 dogs developed cardiac arrhythmias and had elevated troponin levels indicating myocardial damage. One dog necropsied 4 days postdosing had massive myocardial necrosis, mild to focally moderate skeletal muscle necrosis, and widespread segmental arterial mediolysis. A second dog necropsied 17 days postdosing had mild myocardial necrosis and fibrosis. Scattered arteries exhibited segmental medial and perimedial fibromuscular dysplasia. This is the first reported case of arterial, cardiac, and skeletal muscle damage associated with ractopamine.

Further evidence for LBP-1c/CP2/LSF association in Alzheimer's disease families

OBJECTIVES

Several studies suggested chromosome 12 harbours an Alzheimer's disease (AD) risk factor gene. Significant association of a single nucleotide polymorphism (SNP) in the 3' UTR of transcription factor CP2 (LBP-1c/CP2/LSF or TFCP2) at 12q13 was reported in three independent case-control studies, but no family based analyses have been performed to date.

METHODS

Genotypes for three SNPs were generated in two independent AD family samples. A meta-analysis on all published case-control studies was also performed.

RESULTS

The A allele of the 3' UTR SNP was associated with increased risk for AD in one sample (odds ratio (OR) 2.1, 95% confidence interval (95% CI) 1.1 to 4.3), but not in the other, possibly due to low power. Haplotype analyses showed that this allele is part of a putative risk-haplotype overtransmitted to affected individuals in one sample and in both samples combined. Meta-analysis of the previously associated 3' UTR SNP showed a trend towards a protective effect of the A allele in AD (OR 0.73, 95% CI 0.5 to 1.1).

CONCLUSIONS

This is the first study to examine LBP-1c/CP2/LSF in AD families, and the fifth to independently show significant association. While our results support a role of this gene in AD pathogenesis, the direction of the effect remains uncertain, possibly indicating linkage disequilibrium with another variant nearby.

Increased hippocampal activation in mild cognitive impairment compared to normal aging and AD

OBJECTIVE

To use fMRI to investigate whether hippocampal and entorhinal activation during learning is altered in the earliest phase of mild cognitive impairment (MCI).

METHODS

Three groups of older individuals were studied: 10 cognitively intact controls, 9 individuals at the mild end of the spectrum of MCI, and 10 patients with probable Alzheimer disease (AD). Subjects performed a face-name associative encoding task during fMRI scanning, and were tested for recognition of stimuli afterward. Data were analyzed using a functional-anatomic method in which medial temporal lobe (MTL) regions of interest were identified from each individual's structural MRI, and fMRI activation was quantified within each region.

RESULTS

Significantly greater hippocampal activation was present in the MCI group compared to controls; there were no differences between these two groups in hippocampal or entorhinal volumes. In contrast, the AD group showed hippocampal and entorhinal hypoactivation and atrophy in comparison to controls. The subjects with MCI performed similarly to controls on the fMRI recognition memory task; patients with AD exhibited poorer performance. Across all 29 subjects, greater mean entorhinal activation was found in the subgroup of 13 carriers of the APOE epsilon4 allele than in the 16 noncarriers.

CONCLUSIONS

The authors hypothesize that there is a phase of increased medial temporal lobe activation early in the course of prodromal Alzheimer disease followed by a subsequent decrease as the disease progresses.

PEN2 is not a genetic risk factor for Alzheimer's disease in a large family sample

PEN2 is a reasonable Alzheimer's disease (AD) candidate gene because it is a necessary component of the gamma-secretase complex that generates beta-amyloid peptide. Moreover, its gene (PEN2) maps to a highly significant linkage region on chromosome 19q13. Four common polymorphisms in PEN2 were tested for genetic association with AD in a large and carefully ascertained AD family sample (789 subjects from 202 nuclear families) using single-locus and haplotype-based analyses. These results do not suggest PEN2 to be a major AD risk factor.

Materials used in drinking water distribution systems: contribution to taste-and-odor

In order to assist drinking water utilities with identifying the possible sources and causes of taste-and-odor conditions associated with materials used in distribution systems, we evaluated information from case studies and a database from the National Sanitation Foundation (NSF), International. This database identified chemicals that had leached from drinking water system components during testing of materials under ANSI/NSF Standard 61, which provides information to water utilities on potential taste-and-odor and health concerns from the use of new materials. The data were arranged to provide a process for locating the potential source of a taste-and-odor event. After a sensory analysis is conducted on the drinking water samples, the descriptor can be matched with categories on the "Drinking Water Taste and Odor Wheel 2000" in order to suggest the candidate material.

No evidence for genetic association or linkage of the cathepsin D (CTSD) exon 2 polymorphism and Alzheimer disease

Two recent case-control studies have suggested a strong association of a missense polymorphism in exon 2 of the cathepsin D gene (CTSD) and Alzheimer disease (AD). However, these findings were not confirmed in another independent study. We analyzed this polymorphism in two large and independent AD study populations and did not detect an association between CTSD and AD. The first sample was family-based and included 436 subjects from 134 sibships discordant for AD that were analyzed using the sibship disequilibrium test (SDT, p = 0.68) and the sib transmission/disequilibrium test (Sib-TDT, p = 0.81). The second sample of 200 AD cases and 182 cognitively normal controls also failed to show significant differences in the allele or genotype distribution in cases versus controls (chi2, p = 0.91 and p = 0.88, respectively). In addition, two-point linkage analyses in an enlarged family sample (n = 670) did not show evidence for linkage of the chromosomal region around CTSD. Thus, our analyses on more than 800 subjects suggest that if an association between the CTSD exon 2 polymorphism and AD exists, it is likely to be smaller than previously reported.

Evidence for genetic linkage of Alzheimer's disease to chromosome 10q

Recent studies suggest that insulin-degrading enzyme (IDE) in neurons and microglia degrades Abeta, the principal component of beta-amyloid and one of the neuropathological hallmarks of Alzheimer's disease (AD). We performed parametric and nonparametric linkage analyses of seven genetic markers on chromosome 10q, six of which map near the IDE gene, in 435 multiplex AD families. These analyses revealed significant evidence of linkage for adjacent markers (D10S1671, D10S583, D10S1710, and D10S566), which was most pronounced in late-onset families. Furthermore, we found evidence for allele-specific association between the putative disease locus and marker D10S583, which has recently been located within 195 kilobases of the IDE gene.

Candidate genes showing no evidence for association or linkage with Alzheimer's disease using family-based methodologies

Alzheimer's disease (AD) is a genetically complex and heterogeneous disorder. To date, a large number of candidate genes have been associated with the disease, however none of these findings has been consistently replicated in independent datasets. In this study we report the results of family-based analyses for polymorphisms of five such candidates on chromosomes 2 (interleukin-1beta, IL-1B), 3 (butyrylcholinesterase, BCHE), 11 (cathepsin D, CTSD; Fe65, APBB1) and 12 (lipoprotein receptor-related protein-1, LRP1) that were all suggested to be associated with AD in recent case-control studies. To minimize the possibility of spurious findings due to population admixture, we used a family-based design applying the sibship disequilibrium test (SDT) as well as two-point parametric linkage analyses on families from the National Institute of Mental Health (NIMH) Genetics Initiative. Contrary to the initial reports, none of the polymorphisms that were analyzed showed evidence for association or linkage with AD in our families. Our results suggest that the previously reported associations from case-control studies are either (a) false positive results, e.g. due to type I error or population admixture, (b) smaller than initially proposed, or (c) due to linkage disequilibrium with an as yet unidentified polymorphism nearby.

An audit of the processes involved in identifying and assessing bilingual learners suspected of being dyslexic: a Scottish study

The Commission for Racial Equality (Special Educational Needs Assessment in Strathclyde: Report of a Formal Investigation, CRE, London, 1996) highlighted the significant under-representation of bilingual children among pupils assessed as having specific learning difficulties/dyslexia. In this present study an audit was undertaken in order to explore issues arising from the Commission's report, initially using 53 schools from one education authority. This revealed an extremely low incidence of suspected dyslexia among bilingual pupils. A second study was carried out in a further nine education authorities, surveying 91 schools with bilingual pupils. The incidence of suspected dyslexia in bilingual pupils was found to be extremely low. Twenty-seven cases were examined. Most cases concerned pupils aged 7:0-9:0. Difficulties associated with conventional indicators of dyslexia are discussed. A wide variety of assessment approaches were reported and the use of first language (L1) assessment varied. The process of assessment tended to be lengthy and inconclusive. However, this report suggests that caution is necessary when considering dyslexia in the early stages of second language (L2) development.

Excretion of (14)C-fumonisin B(1), (14)C-hydrolyzed fumonisin B(1), and (14)C-fumonisin B(1)-fructose in rats

14C-Fumonisin B(1) (FB(1)) was produced by Fusarium proliferatum M-5991 in modified Myro liquid medium and purified to >95% purity with a specific activity of 1.7 mCi/mmol. Nine male and nine female F344/N rats were each dosed by gavage with 0.69 micromol of (14)C-FB(1), (14)C-hydrolyzed FB(1), or (14)C-FB(1)-fructose/kg body weight. Urinary excretion of (14)C-FB(1) and (14)C-FB(1)-fructose was 0.5% and 4.4% of the total dose, respectively, and was similar between male and female rats. Urinary excretion of (14)C-hydrolyzed HFB(1) was significantly greater (P > 0.05) in female rats as compared with male rats (17.3% vs 12.8% of the total dose, respectively). There were no significant (P > 0.05) differences in biliary excretion of the three fumonisin compounds with a mean of 1. 4% of the dose excreted at 4 h after dosing. Lesser amounts continued to be excreted up to 9.25 h after dosing. Although biliary excretion of the (14)C-FB(1), (14)C-hydrolyzed FB(1), and (14)C-FB(1)-fructose was similar, increased urinary excretion of the (14)C-hydrolyzed FB(1) as compared to (14)C-FB(1) and (14)C-FB(1)-fructose indicated a greater absorption of the hydrolyzed form.

One-year experience with an inpatient asthma clinical pathway

OBJECTIVE

To study the effects of an inpatient asthma clinical pathway on the processes and outcomes for children who were admitted to a hospital for the treatment of asthma.

DESIGN

Before-and-after study.

SETTING

A private nonprofit academic children's hospital in Seattle, Wash.

PATIENTS AND METHODS

Three hundred forty-two admissions of 297 patients in the first year of the asthma clinical pathway were compared with 353 admissions of 292 similar patients in the previous year. Patients who required intensive care, were younger than 2 years, or had a major chronic disease were excluded.

INTERVENTION

Asthma was chosen for the development of a clinical pathway because of its large number of admissions, involvement of multiple health care providers (nurses, physicians, and respiratory therapists), predictable hospital course, and variable lengths of hospital stay. The pathway was a consensus-based guideline for patient management that was intended to be adapted to the care of an individual patient. Prior to the implementation of the clinical pathway, nurses, attending physicians, house staff, and respiratory therapists were trained in its use. The main hospital chart of each patient who was admitted to the pathway had a flowchart that outlined day-to-day guidelines for monitoring and care. Nursing staff were responsible for documenting when a patient's care varied from the pathway, and these variances were entered into a computer database.

OUTCOME MEASURES

Use of peak flowmeters, steroids, laboratory studies, radiological studies, and respiratory therapy was assessed by analyzing the patients' electronic billing records. For patients enrolled in the pathway, additional data on process of care were obtained by analyzing the variance database. For both groups, the total charges, length of stay, and rate of readmission to the hospital were measured by use of the billing records.

RESULTS

There were no significant differences in the use of steroids or peak flowmeters, average lengths of stay, or total charges between the 2 groups. However, patients in the "pathway group" had significantly lower average charges for laboratory ($26 vs $39; P < .05) and radiology ($32 vs $55; P < .001) services. Variances from the pathway guidelines were most often related to the patients' responses to therapy.

CONCLUSIONS

The asthma clinical pathway had no effect on clinical outcomes and small effects on the use of resources. Further development, including physician and nurse training, computer and administrative support, and clinical severity scales, are needed to develop the potential utility of the clinical pathway as a research and quality assurance tool.

Practical nutrition education: special considerations for athletes

The interest in sports nutrition and fitness over the last 10 years has risen beyond our wildest beliefs. Athletes are breaking new records every year, pushing their bodies past points ever thought possible. Athletes must rely on nutrition to help them reach their goals. Books, magazines, newspapers, and television provide the latest information on nutrition and diets, some credible, some not; and athletes are the perfect target for "the magic formula or pill." As health care professionals, we have the responsibility to help our patients to synthesize new information without overlooking the most important thing: the need to follow a well-balanced diet. Nurse practitioners have an opportunity to educate patients on some of the basic sports nutrition information. Nurse practitioners can help patients in distinguishing reliable nutrition information and assist patients in meeting their health and fitness goals with good nutrition practices. The focus of this article is not to provide education regarding nutrition, but to provide simple, useful tools to educate patients and help them meet their goals.

Comprehension monitoring in language-disordered children: a preliminary investigation of cognitive and linguistic factors

This study provided a preliminary investigation of the relative influence of cognitive and communicative factors in comprehension monitoring. This question was approached by studying language-disordered (LD) children for whom these abilities are presumably dissociated. Their performance on an ambiguity detection task was compared to that of two groups of control children, one matched for comprehension level and the other for cognitive level. Results revealed that LD children performed similarly to the control children who were matched for level of comprehension. The LD children's performance was examined along a continuum of the relative influence of cognitive and communicative factors, given that neither type of factor alone could sufficiently account for effective comprehension monitoring. It was concluded that communicative factors, both active primary comprehension and social communicative knowledge, had a stronger influence than the cognitive factors in our particular comprehension monitoring task.

Nonverbal indicants of comprehension monitoring in language-disordered children

This study investigated normal and language-disordered (LD) children's patterns of nonverbal behavior in response to messages varying in degree of ambiguity. Each LD child was matched to two normally developing children: one for comprehension level (LM) and the other for chronological age (CM). All children participated in a videotaped ambiguity detection task. Nonverbal behaviors that were produced between the time the message was completed and the examiner's acknowledgment of the response were scored for type of behavior exhibited including eye contact, hand behavior, body movement, and smile. Results demonstrated that all subjects increased their nonverbal behavior (e.g. eye contact) from unambiguous to ambiguous message conditions, suggesting awareness of the differences in these message types at a rudimentary level. Most often nonverbal indication was the only signal of ambiguity detection exhibited by the LD children and their LM peers. Only the CM children concurrently indicated awareness through more direct means (i.e., verbalization and pointing to all possible referents) in a consistent and accurate manner. The finding that LD children did differentiate inadequate from adequate messages in a rudimentary manner suggests that clinicians might promote the intentionality of these preintentional nonverbal behaviors as a possible intervention strategy.

Studies with 4'-deoxyepivincristine (vinepidine), a semisynthetic vinca alkaloid

The antitumor activity of 4'-deoxyepivincristine (vinepidine, VNP) was examined against a human rhabdomyosarcoma line, HxRh12, grown as a xenograft in immune-deprived mice. The efficacy of VNP was lower than that of vincristine (VCR) but far superior to that of vinblastine (VLB) in this model. After i.p. administration, accumulation of [G-3H]VNP in tumors was biphasic and progressive for at least 72 hr. In contrast, VCR and VLB achieved maximal tumor levels within 4 hr, after which the level of VCR was maintained but VLB levels decreased 3-fold by 72 hr. Analysis of tumor extracts by high performance liquid chromatography showed that at 72 hr after VNP injection 98% of the radiolabel chromatographed with parent compound. In normal tissues, VNP was cleared less rapidly than VCR or VLB, and analyses of tissue extracts suggested that VNP was less rapidly metabolized than VCR or VLB. This may account for why the potency of VNP is greater than that of VCR in mice.

Orientation of medial smooth muscle in the wall of systemic muscular arteries

The study was undertaken to determine the pattern of alignment of muscle cells in the tunica media of muscular arteries. Brachial and femoral arteries from two small Rhesus monkeys and renal arteries from two rabbits were fixed under pressure with formalin, or glutaraldehyde followed by formalin. Sections were cut at 7 micron thickness at specific angles varying from zero to 30 degrees, and then stained with haematoxylin and eosin. The end coordinates of the medial muscle nuclei (appearing dark with the H & E stain) were recorded using a digitizer. Analysis was done as suggested by a previous modelling study by one of the authors; lengths of the individual nuclei as they appeared on the section were plotted as a function of the distance around the perimeter of the vessel. The distribution of lengths was consistent with a truly circumferential pattern of alignment for the muscle nuclei in the wall of muscular arteries. The standard deviation about the average circumferential pattern was +/- 13 degrees in the plane of the histological sections cut in cross section. The number density Nv of 4.4 x 10(5) mm-3 was higher than determined previously for human brain arteries and the nuclear length was 20% shorter (30 micron).