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Biomedical subjects

J B Campbell

Publications and source records attributed to J B Campbell.

At least 19 recordsLinked to original sources
PubMed2001

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.

Animals↗
PubMed2001

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.

Animals↗
PubMed2000

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.

Abnormalities, Multiple↗
PubMed2000

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.

Attitude to Health↗
PubMed2000

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.

Female↗
PubMed1999

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.

Adenocarcinoma↗
PubMed1999

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.

Adult↗
PubMed1999

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.

Child↗
PubMed1999

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.

Aged↗
PubMed1998

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.

Acromion↗
PubMed1997

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.

Animal Husbandry↗
PubMed1997

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.

Animals↗
PubMed1997

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.

Child Abuse↗
PubMed1997

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.

Adolescent↗
PubMed1997

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.

Administration, Oral↗
PubMed1996

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.

Adenylyl Cyclases↗