Future Lyme disease risk in the south-eastern United States based on projected land cover

Lyme disease is the most significant vector-borne disease in the United States, and its southward advance over several decades has been quantified. Previous research has examined the potential role of climate change on the disease's expansion, but no studies have considered the role of future land cover upon its distribution. This research examines Lyme disease risk in the south-eastern U.S. based on projected land cover developed under four Intergovernmental Panel on Climate Change Scenarios: A1B, A2, B1, and B2. Land cover types and edge indices significantly associated with Lyme disease in Virginia were incorporated into a spatial Poisson regression model to quantify potential land cover suitability for Lyme disease in the south-eastern U.S. under each scenario. Our results indicate an intensification of potential land cover suitability for Lyme disease under the A scenarios and a decrease of potential land cover suitability under the B scenarios. The decrease under the B scenarios is a critical result, indicating that Lyme disease risk can be decreased by making different land cover choices. Additionally, health officials can focus efforts in projected high incidence areas.

The evaluation of land consolidation policy in improving agricultural productivity in China

China is presently undergoing rapid economic development and unprecedented urbanization. Concerns over food security have prompted the Chinese government to implement large-scale land consolidation projects. However, no formal evaluation has been conducted on such projects. Thus, effectiveness of land consolidation policy remains uncertain. We obtained detailed geo-spatial information for 5328 land consolidation projects implemented between 2006 and 2010, and used time-series MODIS NDVI (2006-2016) data to assess effectiveness of China's land consolidation policy in improving agricultural productivity. Our results show that the overall effectiveness of land consolidation in improving agricultural productivity is low, which lies in contrast to optimistic estimates based on regional statistical analysis and theoretical approaches. For projects (n = 560) implemented in 2006, about 29.5% showed significant (p < 0.05) increasing trends of MODIS NDVI after implementation of land consolidation. For 2007-2010, lower percentages (e.g., 25.9% in 2007 and 13.5% in 2010) of projects showed significant increasing trends. Furthermore, we found effectiveness of land consolidation projects displayed clear regional differences and driving factors are inconsistent with policy design. We anticipate our research to be a starting point for a more comprehensive evaluation involving longer time-series and higher spatial resolution data.

Inter-rater reliability of the APD, SFU and UTD grading systems in fetal sonography and MRI

INTRODUCTION

Antenatal hydronephrosis (ANH) is frequently detected on screening obstetric ultrasonography. Common ANH grading systems include the anterior-posterior diameter (APD) and the Society for Fetal Urology (SFU) grading system. Recent developments in the management of ANH include the use of fetal magnetic resonance imaging (MRI), and a new grading system - Urinary Tract Dilation (UTD). This study reviewed patients who underwent fetal MRI and ultrasound, and compared the grading systems across these imaging modalities.

MATERIALS AND METHODS

Patients who underwent paired fetal MRI and ultrasound studies between January 2012 and January 2014 were included. Two pediatric urologists and a pediatric radiologist reviewed the studies. Data collected included APD, SFU grade, and UTD grade. Fleiss' kappa statistic determined the inter-rater reliability (IRR) of the SFU and UTD grading within each imaging modality. Intra-class correlation assessed the consistency of the APD measurements.

RESULTS

Forty-seven patients and 88 renal units were evaluated. Median gestational age was 22 weeks. Kappa values of the SFU grading system indicated fair IRR for ultrasound imaging and moderate IRR for MRI imaging, while the UTD grading system reached moderate IRR for both. The IRR of the SFU grading system was improved with the use of MRI, while the UTD grading system was no different. The APD intraclass correlation coefficient improved significantly when measured by MRI. As the ultrasound SFU grade increased, the odds of the MRI SFU grade being scored higher increased by a factor of 3.7. There was no difference between ultrasound and MRI when using the UTD grading system.

DISCUSSION

This study was the first to assess the UTD system in a cohort of patients who underwent paired ultrasound and MRI studies. The results suggested that the UTD system might improve IRR, compared with the SFU system. The use of fetal MRI may improve the IRR of the SFU grading system. It also found that the proportion of SFU grades was affected by the imaging modality, raising the possibility that MRI 'overcalls' the SFU grade, compared with ultrasound. This difference was not observed using the UTD grading system. The most important limitation was the selection bias favoring complex pathology with severe ANH diagnosed at an early gestational age.

CONCLUSIONS

In this unique cohort, the UTD system improved IRR when compared to the SFU grading system. Fetal MRI improved the IRR of the SFU grading system, and improved the APD intraclass correlation. The SFU grading was likely to be higher when assessed by MRI vs ultrasound, but the UTD grade was not affected by the imaging modality.

An Examination of the Demographic and Environmental Variables Correlated with Lyme Disease Emergence in Virginia

Lyme disease is the United States' most significant vector-borne illness. Virginia, on the southern edge of the disease's currently expanding range, has experienced an increase in Lyme disease both spatially and temporally, with steadily increasing rates over the past decade and disease spread from the northern to the southwestern part of the state. This study used a Geographic Information System and a spatial Poisson regression model to examine correlations between demographic and land cover variables, and human Lyme disease from 2006 to 2010 in Virginia. Analysis indicated that herbaceous land cover is positively correlated with Lyme disease incidence rates. Areas with greater interspersion between herbaceous and forested land were also positively correlated with incidence rates. In addition, income and age were positively correlated with incidence rates. Levels of development, interspersion of herbaceous and developed land, and population density were negatively correlated with incidence rates. Abundance of forest fragments less than 2 hectares in area was not significantly correlated. Our results support some findings of previous studies on ecological variables and Lyme disease in endemic areas, but other results have not been found in previous studies, highlighting the potential contribution of new variables as Lyme disease continues to emerge southward.

Spatial and temporal emergence pattern of Lyme disease in Virginia

The emergence of infectious diseases over the past several decades has highlighted the need to better understand epidemics and prepare for the spread of diseases into new areas. As these diseases expand their geographic range, cases are recorded at different geographic locations over time, making the analysis and prediction of this expansion complicated. In this study, we analyze spatial patterns of the disease using a statistical smoothing analysis based on areal (census tract level) count data of Lyme disease cases in Virginia from 1998 to 2011. We also use space and space-time scan statistics to reveal the presence of clusters in the spatial and spatiotemporal distribution of Lyme disease. Our results confirm and quantify the continued emergence of Lyme disease to the south and west in states along the eastern coast of the United States. The results also highlight areas where education and surveillance needs are highest.

Synthesis and SAR of aminothiazole fused benzazepines as selective dopamine D2 partial agonists

Dopamine (D(2)) partial agonists (D2PAs) have been regarded as a potential treatment for schizophrenia patients with expected better side effect profiles than currently marketed antipsychotics. Herein we report the synthesis and SAR of a series of aminothiazole fused benzazepines as selective D(2) partial agonists. These compounds have good selectivity, CNS drug-like properties and tunable D(2) partial agonism. One of the key compounds, 8h, has good in vitro/in vivo ADME characteristics, and is active in a rat amphetamine-induced locomotor activity model.

Improving lead generation success through integrated methods: transcending 'drug discovery by numbers'

Key methodologies such as HTS and combinatorial chemistry have allowed pharmaceutical discovery to focus on identifying promising drug candidates through the use of statistics. Thus, amassing large data sets from large-scale screening campaigns of ever-increasing corporate compound collections was expected to deliver unprecedented success for the pharmaceutical industry. This feature review explores aspects of how the reliance on using numbers to drive discovery has gone awry. Building knowledge equity from the integration of multiple parallel screening assays, workstreams and data sources provides an alternative to driving discovery through statistics. Thus, a more rational approach to creating and inventing new leads and drug opportunities may be pursued.

Elucidation of a novel bioactivation pathway of a 3,4-unsubstituted isoxazole in human liver microsomes: formation of a glutathione adduct of a cyanoacrolein derivative after isoxazole ring opening

Studies on the biotransformation of isoxazole rings have shown that molecules containing a C3-substituted isoxazole or a 1,2-benzisoxazole can undergo a two-electron reductive ring cleavage to form an imine. In the absence of a C3 substituent, the isoxazole ring opens via deprotonation of the C3 proton followed by N-O bond cleavage to yield an α-cyanoenol analog. We report the identification of a novel bioactivation pathway of a 3,4-unsubstituted isoxazole in human liver microsomes. After the enzyme-catalyzed cleavage of the 3,4-unsubstituted isoxazole ring of N-((2-isopropyl-7-methyl-1-oxoisoindolin-5-yl)methyl)isoxazole-5-carboxamide (P) in human liver microsomes, the formed α-cyanoenol (M1) condenses with formaldehyde to generate an α,β-unsaturated Michael acceptor intermediate (a cyanoacrolein derivative, VII), which further reacts with the cysteinyl thiol of glutathione to yield a GSH adduct of a cyanoacrolein derivative (M3). The same adduct also is formed when M1, generated in 0.1 N NaOH aqueous solution, reacts with formaldehyde and GSH. (13)C-labeled methanol was used to confirm that methanol from the drug stock solution was oxidized by liver microsomal enzymes to formaldehyde and the carbon atom from methanol was finally incorporated in the corresponding GSH adduct. The formation of isoxazole ring-opened products (M1 and M2) in human liver microsomes is NADPH-dependent. M1 and M2 were found in human liver microsomes preincubated with 1-aminobenzotriazole (1 mM) and NADPH (5 mM) at ∼ 10% of the levels found in the samples in the absence of 1-aminobenzotriazole, suggesting that this biotransformation pathway is primarily catalyzed by cytochrome P450. The formation of M3 also was inhibited by 1-aminobenzotriazole at a similar level.

Dispersal of stable flies (Diptera: Muscidae) from larval development sites in a Nebraska landscape

Seven mark-recapture studies were conducted over 3 yr to assess dispersal of newly emerging adult stable flies, Stomoxys calcitrans L., from larval development sites in a mixed agricultural environment in northeastern Nebraska. Infested hay debris piles were marked by dusting their surfaces with fluorescent pigments, adults were captured with surrounding grids of Alsynite sticky traps, and specimens were dissected to determine feeding histories and reproductive age. Distances and directions of 3,889 marked specimens indicated males and females dispersed equally and in all directions. Midguts of males and females were equally likely to contain blood-meal remnants. Percentage with blood remnants and percentage of females with yolk increased with distance from mark origin, indicating survival and spread were positively associated with host finding success. A time-integrated diffusion model fit to results from the seven studies indicated 50% of stable fly adults had dispersed beyond 1.6 km of their natal site, but only 5% had dispersed beyond 5.1 km. These results indicate that stable fly adults on cattle in a given area are most likely to have originated from larval development sites within an ≈ 5 km radius of the subject cattle.

Application of fragment-based lead generation to the discovery of novel, cyclic amidine beta-secretase inhibitors with nanomolar potency, cellular activity, and high ligand efficiency

Fragment-based lead generation has led to the discovery of a novel series of cyclic amidine-based inhibitors of beta-secretase (BACE-1). Initial fragment hits with an isocytosine core having millimolar potency were identified via NMR affinity screening. Structure-guided evolution of these fragments using X-ray crystallography together with potency determination using surface plasmon resonance and functional enzyme inhibition assays afforded micromolar inhibitors. Similarity searching around the isocytosine core led to the identification of a related series of inhibitors, the dihydroisocytosines. By leveraging the knowledge of the ligand-BACE-1 recognition features generated from the isocytosines, the dihydroisocytosines were efficiently optimized to submicromolar potency. Compound 29, with an IC50 of 80 nM, a ligand efficiency of 0.37, and cellular activity of 470 nM, emerged as the lead structure for future optimization.

Attitudes toward vaccination: a survey of Canadian chiropractic students

BACKGROUND

Although the Canadian Chiropractic Association and the Canadian Memorial Chiropractic College (CMCC) endorse vaccination, the prevalence of anti-vaccination attitudes among Canadian chiropractors is unknown. This study describes the prevalence of anti-vaccination attitudes among Canadian chiropractic students.

METHODS

An 11-item questionnaire about attitudes toward vaccination was distributed to students enrolled at CMCC during the 1999/2000 academic year. The responses for the 11 items were then summed to arrive at a total score ranging from 0 (most negative attitude toward vaccination) to 22 (most positive attitude toward vaccination). Respondents' perceptions of sources of vaccine information were also investigated.

RESULTS

Over 75% of the students (467 of 621) completed the questionnaire. Most students (53.3%) reported that in general they agreed with vaccination. This was especially true among first-year students (60.7%). However, among fourth year students, only 39.5% agreed with vaccination. The proportion of respondents who stated that they were against vaccination in general was 5 (4.5%) of 112 first-year students, 10 (8.3%) of 121 second-year students, 16 (13.9%) of 115 third-year students and 35 (29.4%) of 119 fourth-year students. The mean scores on the questionnaire were progressively lower with each higher year of study at the College. The mean survey scores for each year of study were first year, 15.9 (95% confidence interval [CI] 15.2-16.6); second year, 16.1 (95% CI 15.3-1 7.0); third year, 14.5 (95% CI 13.5-15.4); and fourth year, 12.8 (95% CI 11.7-13.9). The mean scores varied among year of study and were statistically significant using one-way ANOVA (p < 0.0001). Among students who relied primarily on informal sources of vaccine information, such as the chiropractic literature and informal talks at CMCC, anti-vaccination attitudes were more prevalent in later years.

INTERPRETATION

Most CMCC students reported pro-vaccination attitudes, but there appeared to be an increase in anti-vaccination attitudes as students progressed through the CMCC program. This pattern was seen almost exclusively among students who relied primarily on informal sources of vaccine information rather than on core CMCC lectures or prior lectures at university.

Effects of stable flies (Diptera: Muscidae) on weight gains of grazing yearling cattle

Differences in weight gains caused by stable flies, Stomoxys calcitrans (L.), on grazing yearling steer/calves averaged 0.2 kg per steer in a 3-yr study on canyon range pastures in West Central Nebraska, Stable fly numbers averaged 0.85 per front leg on treated calves and 3.64 per front leg on control calves. In 2 of the 3 yr after the grazing trials were completed, the calves were placed in a feedlot and fed a finishing ration. Compensatory gain did not occur in the feedlot after the stable fly stress was removed.

Comparative efficacy of several insecticides for control of cattle lice (Mallophaga: Trichodectidae and Anoplura: Haematopinidae)

Several insecticides were applied to cattle at various rates, mixtures, application methods and numbers of treatments and evaluated for control of cattle lice. The insecticides included permethrin at various rates as a pour-on with and without the synergist piperonyl butoxide (PBO), and also at various rates as a spray with and without PBO. Pirimiphos-methyl was evaluated as a pour-on at various rates and with one or two applications. Lambda cyhalothrin in microencapsulated formulation was compared to a non-microencapsulated formulation. Rabon(R) was applied as a pour-on at two rates and at one or two treatments for each rate. Dimilin(R) was applied as a pour-on at two rates and mixed with permethrin and applied at two rates. Five endectocides, Eprinex(R), Ivomec(R), Dectomax(R), Cydectin(R) and Phoenectin(R) were all applied at the same rate. The cattle utilized in this research were all infested with a mixture of lice species. The species included: Bovicola (Damalinia) bovis (L.), Haematopinus eurysternus (Nitzsch), Linognthus vituli (L.) and Solenoptes capillatus (Enderlein). Most of the cattle were infested with at least two species and some had three or all four species present. All of the treatments except permethrin 1.0%+5% PBO, at a rate of 3ml/45.4kgwt. provided acceptable lice control with one application. Data indicated that applying the insecticides in early January should provide enough control to render the need for a second treatment unnecessary.

Chiropractors and vaccination: A historical perspective

Although there is overwhelming evidence to show that vaccination is a highly effective method of controlling infectious diseases, a vocal element of the chiropractic profession maintains a strongly antivaccination bias. Reasons for this are examined. The basis seems to lie in early chiropractic philosophy, which, eschewing both the germ theory of infectious disease and vaccination, considered disease the result of spinal nerve dysfunction caused by misplaced (subluxated) vertebrae. Although rejected by medical science, this concept is still accepted by a minority of chiropractors. Although more progressive, evidence-based chiropractors have embraced the concept of vaccination, the rejection of it by conservative chiropractors continues to have a negative influence on both public acceptance of vaccination and acceptance of the chiropractic profession by orthodox medicine.

Jansen type of spondylometaphyseal dysplasia

Metaphyseal dysplasia, type Jansen (JMD), is a rare skeletal dysplasia with characteristic radiographic abnormalities. Of the various types of metaphyseal dysplasia, JMD shows the most severe alteration in metaphyseal architecture. All of the long tubular bones, including those of the hands and feet, show metaphyseal irregularity with a fragmented appearance and slight widening. The adjacent physes are abnormally widened, while the epiphyses tend to be slightly enlarged, rounded but otherwise normal. The spine in infancy and childhood usually appears normal. This report describes a young girl with metaphyseal changes typical of JMD except for the hands and feet, which appeared normal. She also showed very unusual abnormalities of the spine. This appears, therefore, to represent a unique osteochondrodysplasia for which we propose the term spondylometaphyseal dysplasia, type Jansen.

Hepatic pulmonary fusion in neonates

OBJECTIVE

This report discusses the relationship of supradiaphragmatic hepatic tissue that is fused to the lung (through a diaphragmatic defect) with pulmonary hypoplasia-a new constellation of findings.

CONCLUSION

Hepatic pulmonary fusion should be suspected in instances of apparent diaphragmatic hernia characterized by mediastinal shift towards the hypoplastic lung or when the mediastinum does not shift away from the mass.

Metaphyseal chondrodysplasia, type Jansen

The Jansen type of metaphyseal dysplasia is a rare disorder with significant clinical and radiographic variability. Two cases of classical Jansen disease and one with some distinctive features suggestive of the Jansen variant are reported.

Fibrogenesis imperfecta ossium: imaging correlation in three new patients

OBJECTIVE

Fibrogenesis imperfecta ossium is an extremely rare disorder that can easily be misdiagnosed. We retrospectively reviewed the clinical and imaging data of three confirmed cases of fibrogenesis imperfecta.

DESIGN AND PATIENTS

The patients consisted of two men and one woman, ranging in age from 40 to 53 years. Radiography was performed in all the patients. One patient had a 3-year follow-up of the thoracolumbar spine with conventional radiography and thoracolumbar magnetic resonance (MR) imaging. Open biopsy was performed in all cases, confirming the diagnosis of fibrogenesis imperfecta ossium.

RESULTS

All our cases demonstrated "fishnet" trabecular pattern by conventional radiographs, and a pelvis radiograph of one patient showed an equivocal sclerosis pattern. Multiple fractures were noted in two patients. A pseudoexostosis was present in the ilium in one patient. Thoracolumbar MR imaging demonstrated diffuse low signal intensity within the medullary space on both T1-weighed and T2-weighted images, except for a region of increased signal intensity in the L1 and L2 vertebral bodies on T2-weighed images due to edema from acute collapse.

CONCLUSIONS

Although uncommon, fibrogenesis imperfecta ossium should be considered in a previously healthy patient with a combination of progressive bone pain, unexplained fractures, a radiologic pattern of fishnet osteopenia and MR imaging of low signal intensity bone marrow on both T1-weighted and T2-weighted images.

Use of nonprescription medications by patients with congestive heart failure

OBJECTIVE

To define the utilization pattern of nonprescription therapies in patients with congestive heart failure (CHF) and to compare this pattern with that of an age- and gender-matched control group without any self-reported heart conditions.

DESIGN

Survey questionnaire completed by participants at home.

SETTING

Ambulatory CHF clinic in a tertiary care hospital.

SUBJECTS

Patients attending the clinic between July 1995 and May 1996 who agreed to participate. Control subjects were age- and gender-matched participants identified and approached by participating patients.

OUTCOME MEASURES

Nonprescription therapies used at least once weekly.

RESULTS

Completed questionnaires were received from 180 (75%) of the 239 patients who agreed to participate and from 133 controls. Mean age of responding patients was 69 years (63% men). Controls were younger, with a mean age of 64 years (63% men). The most commonly used nonprescription medication categories for both patients and controls, with no significant intergroup differences, were vitamins and minerals (59% patients, 50% controls), pain relievers (48% and 43%, respectively), herbal or health food products (38% and 38%), antacids (26% and 28%), and laxatives (24% and 21%). Significantly fewer patients than controls used cough and cold products (9% vs. 17%; p < 0.05), specifically oral decongestants (0.6% vs. 5%; p < 0.01), and more patients than controls used nutritional supplements (17% vs. 4%; p < 0.01).

CONCLUSIONS

Overall, use of nonprescription therapies by our CHF clinic patients is similar to that of an age- and gender-matched population without a self-reported heart condition. The differences in medication use observed between patients and controls included cough and cold products that might be harmful. This likely reflects appropriate caution with which CHF patients approach nonprescription therapies.

Malignancies in pediatric patients with ataxia telangiectasia

BACKGROUND

Patients with ataxia telangiectasia (AT), known to have an inherent increased susceptibility to the development of cancer, may present with malignancies that are unusual for the patient's age, are often difficult to diagnose clinically and radiographically and respond poorly to conventional therapy.

MATERIALS AND METHODS

We reviewed the clinical presentation and imaging studies of 12 AT patients who developed malignancies.

RESULTS

Eight of the twelve patients developed non-Hodgkin's lymphoma (CNS, thorax, bone), two developed Hodgkin's disease, and two were diagnosed with gastrointestinal mucinous adenocarcinoma.

CONCLUSION

The lymphomas were commonly extra nodal, and infiltrative rather than mass-like. The recognition of the tumors was often delayed due to confusion with the known infectious complications in AT patients.

Upper extremity and rib stress fractures in a child

Stress fractures in children are rare compared with the incidence in adults. This report describes an 11-year-old girl with stress fractures of the acromion, clavicle, and first rib on the left and contralateral fractures of the first and second ribs. It was eventually discovered that these fractures were caused by a nervous tic consisting of repetitive, vigorous shrugging and translation of the shoulders.

Chylothorax as a manifestation of child abuse

OBJECTIVE

Chylothorax presenting in a child without a well defined etiology may be a manifestation of child abuse. We recently observed a child with bilateral chylothoraces who demonstrated coexisting nonaccidental injuries. It is our intention to alert physicians to the association of chylothorax with nonaccidental trauma and review the prior medical literature.

DESIGN

Case report.

SETTING

Pediatric emergency department and intensive care unit.

PATIENT

An 18-month-old female child who presented with respiratory distress and failure to thrive.

INTERVENTIONS

Diagnostic and therapeutic thoracentesis. Skeletal survey and radionuclide bone scan. Nutritional support.

OUTCOME MEASURES

Pleural fluid is characterized as chylous if it contains significant numbers of lymphocytes and lipid. Unexplained fractures of the ribs and long bones in varying stages of healing are considered nonaccidental. Failure to thrive may be considered nonorganic when nutritional support alone results in significant weight gain.

RESULTS

Our patient presented with respiratory distress of one-week duration and failure to gain weight during the prior five months. The chest radiograph demonstrated bilateral pleural effusions, which were aspirated. The aspirate contained 1733 cells/mm3 (98% lymphocytes), which were lipid laden. The triglyceride concentration was 806 mg/dl. A skeletal survey demonstrated bilateral first rib, clavicle, and ulnar fractures. A radionuclide bone scan additionally revealed multiple vertebral body fractures. Nutritional support alone resulted in significant weight gain. The patient was reported to local authorities as having been abused.

CONCLUSION

Child abuse should be considered as an etiology for cryptogenic chylothorax. Further studies should be undertaken in this circumstance to search for coexisting injuries, which may indicate nonaccidental trauma.

Susceptibility of stable flies (Diptera:Muscidae) from southeastern Nebraska beef cattle feedlots to selected insecticides and comparison of 3 bioassay techniques

Insecticide susceptibility of field populations of stable flies, Stomoxys calcitrans (L.), was assayed using 3 exposure techniques: treated filter papers, treated glass petri dishes, and topical applications. Both topical applications and residual exposure to treated glass surfaces were suitable for testing susceptibility of stable flies to permethrin, stirofos, or methoxychlor. Residues on filter papers yielded inconsistent results with stirofos and methoxychlor. Significant concentration-mortality regression lines were generated with permethrin residues on filter papers, but approximately 1,000 times more insecticide was required to produce a toxic response when compared with permethrin residues on glass. Because of higher variability in response and the greater amount of insecticide required, residues on filter papers do not appear appropriate to test insecticide susceptibility in stable flies. Paired comparisons of field (F) and susceptible (S) stable flies resulted in field to susceptible ratios significantly > 1.0 only when the flies were treated topically, which suggests that topical application is more sensitive than residues on glass for the insecticides tested. Topical treatment with permethrin resulted in one FS(LD90) of 1.8-fold. Topical treatment with methoxychlor resulted in one FS(LD90) of 3.4-fold. However, the magnitude of these ratios is not larger than the significant differences observed within the susceptible laboratory colony from one generation to another. Intense exposure to insecticides is not known to have occurred in these field populations, indicating that the observed differences are the result of natural variation among stable fly populations and unrelated to prior selection with insecticides.

Calculating economic injury levels for stable flies (Diptera:Muscidae) on feeder heifers

A procedure for calculating the economic injury levels for stable flies, Stomoxys calcitrans (L.), on feeder heifers was developed from reduction of average daily weight gain-stable fly population level data in 8 independent replicated experiments over 17 yr. A negative exponential was fitted to the data using nonlinear regression. Regression coefficients were then used to derive a simple predictive equation for calculating the economic injury level in relation to cost of controlling stable flies in the feedlot, and the market value of heifers. Examples for calculating the economic injury level under practical feedlot situations are presented. Also included are recommendations for a simple random sampling design for stable flies in feedlots.

The effects of disposable daily wear contact lenses on goblet cell count

PURPOSE

The number of goblet cells on the inferior bulbar conjunctiva increases in response to daily wear contact lens use. We conducted a study to examine whether daily wear soft contact lenses worn on a 2-week disposable schedule would also induce the same goblet cell response.

METHODS

Twenty-eight subjects who had never worn contact lenses were fit with 38% water polymacon lenses. The lenses were worn on a daily wear basis and replaced every two weeks over a 6-month period. Goblet cell count was determined by impression cytology of the inferior bulbar conjunctiva.

RESULTS

No significant increase in goblet cell count was observed in the subjects during the 6 months period; the 3.23% baseline goblet cell count was never exceeded. In our previous study, after 6 months of conventional daily wear lens use, the goblet cell count increased from a baseline of 4.19% to 8.0%.

CONCLUSIONS

It appears that wearing daily wear soft contact lenses on a disposable basis may be less irritating to the ocular surface than wearing soft contact lenses on a conventional daily wear basis.

Duration of immunity in foxes vaccinated orally with ERA vaccine in a bait

Red foxes (Vulpes vulpes) vaccinated orally with the ERA strain of rabies vaccine in a bait were challenged after 83 mo. Ten of 11 foxes that had seroconverted following vaccination resisted challenge with a virulent rabies virus which produced clinical signs of rabies in 6 of 6 unvaccinated foxes. Five of 11 vaccinated animals retained titers of rabies virus neutralizing antibody throughout the period. Although 6 of 11 had no detectable antibody at the time of challenge, 5 of these 6 resisted challenge and had an anamnestic response, as indicated by elevated titers of antibody when measured at day 77 postchallenge. These results show that foxes can be immunized successfully with a single oral dose of ERA vaccine, probably with protection against a lethal rabies challenge, for at least 7 y.

Addition of Transiently-Generated Methyl o-Lithiobenzoate to Imines. An Isoindolone Annulation

Addition of phenyllithium to a mixture of an imine, methyl o-iodobenzoate, and BF(3).etherate at -105 degrees C gives good to excellent yields of isoindolones. The transient formation of methyl o-lithiobenzoate is proposed, which is formed by a rapid lithium/iodide exchange reaction of the phenyllithium with methyl o-iodobenzoate in the presence of the imine. The transiently generated anions can then be captured by the BF(3)-activated imines to form the isoindolones in good to high yield. The reactions conditions are sufficiently mild, and selective, to permit functional groups such carbmethoxy and aryl bromide, which could otherwise react with the added PhLi, to be tolerated.

Human adenovirus type 5 vectors expressing rabies glycoprotein

The prevalence of wildlife rabies throughout the world and the continued spread of this disease in North America highlights the need for oral vaccines which may be used safely and effectively to vaccinate a number of species that are reservoirs or vectors of rabies. We have previously shown that AdRG1, a replication competent recombinant human adenovirus type 5 (Ad5) expressing a rabies glycoprotein (RG), can induce immunity to rabies in rodent, canine, and skunk model systems. To improve the Ad5 vector system as a potential oral vaccine, we have constructed additional Ad5 recombinant vectors and compared RG expression in cell culture and immunogenicity in animals. Two new replication competent vectors are compared. AdRG1.3, which carries RG with accompanying SV40 poly A addition sequences within an E3 deletion, and AdRG4, which has RG in the E3 deletion but under the control of an exogenous Ad2 major late promoter, both express higher levels of RG in permissive cell culture than did AdRG1 and both elicit high levels of serum anti-rabies antibodies by parenteral or oral routes in animals. AdRG1.3 may be a more effective vaccine vector in species which are non-permissive for the replication of human Ad5.

Cause-specific noncardiac mortality in patients with congestive heart failure--a contemporary Canadian audit. Clinical Quality Improvement Network (CQIN) Investigators

BACKGROUND

Noncardiac mortality in congestive heart failure (CHF) is substantial.

OBJECTIVE

To define the specific causes of noncardiac mortality among hospitalized CHF patients.

DESIGN

Retrospective medical record audit.

SETTING

Three hospitals in British Columbia and Alberta, 1992-93.

PATIENTS

A total of 2216 consecutive patients admitted with CHF.

MAIN RESULTS

The overall mortality rate was 404 of 2216 (18%). Cause of death was cardiac in 290 of 404 (72%) patients, with an average age of 76 years. However, 114 of 404 (28%) deaths, in patients with an average age of 69 years, had noncardiac causes. Four causes accounted for almost 70%, of the noncardiac deaths: cancer (24%); pneumonia (16%); other pulmonary diseases, including embolism (15%); and cerebrovascular disease (11%). Renal disease (9%), gastrointestinal disorders (9%), non-pulmonic sepsis (7%), multiple system failure (5%) and trauma or surgical complications (4%) accounted for most of the remaining noncardiac deaths.

CONCLUSIONS

Noncardiac causes produce a substantial proportion of deaths among elderly and sick CHF patients. As the survival of patients with CHF improves, the relative risk of noncardiac mortality in this population will likely increase. However, since hospitalized CHF patients so closely reflect their general population counterparts in terms of cause-specific mortality risk, the search for an ideal therapy might be viewed as a quixotic search for the cure of death.

Synthesis of the four isomers of 4-aminopyrrolidine-2,4-dicarboxylate: identification of a potent, highly selective, and systemically-active agonist for metabotropic glutamate receptors negatively coupled to adenylate cyclase

The four isomers of 4-aminopyrrolidine-2,4-dicarboxylate (APDC) were prepared and evaluated for their effects at glutamate receptors in vitro. (2R,4R)-APDC (2a), an aza analog of the nonselective mGluR agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate (1S,3R)-ACPD, 1), was found to possess relatively high affinity for metabotropic glutamate receptors (mGluRs) (ACPD-sensitive [3H]glutamate binding IC50 = 6.49 +/- 1.21 microM) with no effects on radioligand binding to NMDA, AMPA, or kainate receptors up to 100 microM. None of the other APDC isomers showed significant mGluR binding affinity, indicating that this interaction is highly stereospecific. Both 1 and 2a were effective in decreasing forskolin-stimulated cAMP formation in the adult rat cerebral cortex (EC50 = 8.17 +/- 2.21 microM for 1; EC50 = 14.51 +/- 5.54 microM for 2a); however, while 1 was also effective in stimulating basal tritiated inositol monophosphate production in the neonatal rat cerebral cortex (EC50 = 27.7 +/- 5.2 microM), 2a (up to 100 microM) was ineffective in stimulating phosphoinositide hydrolysis in this tissue preparation, further supporting our previous observations that 2a is a highly selective agonist for mGluRs negatively coupled to adenylate cyclase. Microelectrophoretic application of either 1 or 2a to intact rat spinal neurons produced an augmentation of AMPA-induced excitation (95 +/- 10% increase for 1, 52 +/- 6% increase for 2a). Intracerebral injection of 1 (400 nmol) produced characteristic limbic seizures in mice which are not mimicked by 2a (200-1600 nmol, ic). However, the limbic seizures induced by 1 were blocked by systemically administered 2a in a dose-dependent manner (EC50 = 271 mg/kg, ip). It is concluded that (2R,4R)-APDC (2a) is a highly selective, systemically-active agonist of mGluRs negatively coupled to adenylate cyclase and that selective activation of these receptors in vivo can result in anticonvulsant effects.

Comparison of core sampling and pupal traps for monitoring immature stable flies and house flies (Diptera: Muscidae) in beef feedlot pens

Core samples and cylindrical pupal traps were used to monitor immature stages of the stable fly, Stomoxys calcitrans (L.), and house fly, Musca domestica L., from 5 sample areas in beef feedlot pens: the feed apron-soil interface, the back fence, the side (pen dividing) fence, the mound, and the general lot. One feedlot was sampled during 1986, two feedlots were sampled in 1987, and three samples were taken at random from each sample area on each sample date. Core samples showed that both populations were highest from the feed apron sample area. Pupal traps tended to show the same result but differences between sample areas were not significant for immature stable flies. Both sampling methods generally indicated similar population trends of the 2 fly species over the season; correlation coefficients between the 2 sampling methods were generally significant but few correlations were strong and large divergences between population trends were present. Only approximately 69% of the total number of pupal traps placed were recovered; the loss of traps could have contributed to differences between the 2 sampling methods. Core sampling would be preferred if lower variance of samples is important; if collecting pupae of known age is important, then pupal traps may be useful if they are protected from trampling by cattle.

Scheduled sanitation to reduce stable fly (Diptera: Muscidae) populations in beef cattle feedlots

Sanitation has been long recommended as a means of reducing stable fly, Stomoxys calcitrans (L.), populations at cattle feedlots, but there is little published research to support this recommendation. In each of the 2 yr of this study, 4 feedlots received complete sanitation and 4 feedlots received no cleaning. The objective was to have the initial cleaning done before 1 June and then to reclean as needed every 2 wk thereafter. The feedlots that were cleaned had significantly fewer flies than the uncleaned feedlots, with 50.9% fewer stable flies during the 1st yr and 36.2% fewer flies in the 2nd yr. These reductions were realized even though initial cleaning was not done by 1 June in either year: bad weather delayed completion until 20 June the 1st yr and 29 June the 2nd yr. Sanitation at cattle feedlots significantly reduces stable fly populations and sanitation may have been more effective if initial cleaning was done by 1 June.

Should nasopharyngeal biopsy be mandatory in adult unilateral glue ear?

Unilateral secretory otitis media is a recognized presenting feature of nasopharyngeal neoplasia. In the two cases presented, biopsy from the nasopharynx revealed an unsuspected underlying adenocarcinoma. The need to biopsy the normal looking post-nasal space is highlighted.