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H M Campbell

Publications and source records attributed to H M Campbell.

11 recordsLinked to original sources
PubMed2001

Evaluating microbial indicators of environmental condition in Oregon rivers.

Traditional bacterial indicators used in public health to assess water quality and the Biolog system were evaluated to compare their response to biological, chemical, and physical habitat indicators of stream condition both within the state of Oregon and among ecoregion aggregates (Coast Range, Willamette Valley, Cascades, and eastern Oregon). Forty-three randomly selected Oregon river sites were sampled during the summer in 1997 and 1998. The public health indicators included heterotrophic plate counts (HPC), total coliforms (TC), fecal coliforms (FC) and Escherichia coli (EC). Statewide, HPC correlated strongly with physical habitat (elevation, riparian complexity, % canopy presence, and indices of agriculture, pavement, road, pasture, and total disturbance) and chemistry (pH, dissolved O2, specific conductance, acid-neutralizing capacity, dissolved organic carbon, total N, total P, SiO2, and SO4). FC and EC were significantly correlated generally with the river chemistry indicators. TC bacteria significantly correlated with riparian complexity, road disturbance, dissolved O2, and SiO2 and FC. Analyzing the sites by ecoregion, eastern Oregon was characterized by high HPC, FC, EC, nutrient loads, and indices of human disturbance, whereas the Cascades ecoregion had correspondingly low counts of these indicators. The Coast Range and Willamette Valley presented inconsistent indicator patterns that are more difficult to characterize. Attempts to distinguish between ecoregions with the Biolog system were not successful, nor did a statistical pattern emerge between the first five principle components and the other environmental indicators. Our research suggests that some traditional public health microbial indicators may be useful in measuring the environmental condition of lotic systems.

Bacteria↗
PubMed1998

The red board.

Explore the source record for details and available documents.

Aged↗
PubMed1995

Foveal adaptation abnormalities in early glaucoma.

Foveal sensitivities were measured after onset of adapting background fields for each of the following four groups of subjects aged 40-70 years: (1) low-tension glaucoma subjects with minimal field loss in the test eye, (2) primary open-angle glaucoma subjects with minimal field loss in the test eye, (3) normal control subjects, and (4) subjects originally enrolled as control subjects but subsequently found, on the basis of masked clinical evaluation, to be suspect for glaucoma despite ostensibly normal intraocular pressures. We found that the desensitization of a short-wavelength-sensitive-cone-mediated response after onset of a 580-nm background field was diminished from that of normal observers for low-tension glaucoma subjects but not for primary open-angle glaucoma subjects. The desensitization was also diminished for a glaucoma-suspect subjects aged 60-70 years. In contrast, the flicker sensitivity instabilities that persisted after onset of a long-wavelength background field for the majority of subjects with primary open-angle glaucoma [J. Glaucoma Suppl. 3, S19 (1994)] occurred only infrequently among the other subject groups. These results imply that glaucoma often involves the fovea, probably by affecting retinal subtractive adaptation processes, although with different consequences for different types of glaucoma. The results also suggest that undiagnosed low-tension glaucoma may not be rare in the general aging population.

Adaptation, Ocular↗
PubMed1994

The palatal canine and the adjacent lateral incisor: a study of a west of Scotland population.

The hypothesis that palatally-displaced canines are associated with smaller than average lateral incisors or with congenital absence of adjacent lateral incisors was tested on a West of Scotland population. A retrospective study of the records of orthodontic patients attending Glasgow Dental Hospital was carried out. One-hundred-and-eighty-two subjects with palatally displaced canines were identified. The tooth length of lateral and central incisors was measured on radiographs and the crown widths of lateral incisors were measured on study casts. One-hundred-and-six extracted maxillary lateral incisors were examined to allow more accurate measurement of crown width and root length than was possible from radiographs. An association was sought between the size of the lateral incisor or its absence, the position of the adjacent maxillary canine, and between crown size and root length of the lateral incisor. The conclusions supported the hypothesis that there is a weak association between palatally displaced maxillary canines and lateral incisors of smaller than average crown width. There was weak support for the association between palatal canines and absence of the adjacent lateral incisor. There was no correlation between lateral incisor crown width and root length.

Adolescent↗
PubMed1980

Barrier animal facility operations for a large-scale chronic study (ED01 study).

The physical facilities of the specific pathogen free/defined flora barrier animal rooms and their support operations are described as used in the conduct of a large-scale, long-term, low-dose carcinogenicity study. Specifically described are the floor plan of the facility, the mechanical operations, air flow, temperature and humidity controls, personnel screening and requirements, cleaning operations, and traffic flow patterns of personnel, equipment, and animals.

Animals↗
PubMedDate not supplied

Cryptococcus neoformans var. gattii infection in northern Australia: existence of an environmental source other than known host eucalypts.

The 2 known host trees of Cryptococcus neoformans var. gattii, Eucalyptus camaldulensis and E. tereticornis, do not occur naturally in the 'Top End' of the Northern Territory (NT) of Australia. Nine clinical isolates of C. neoformans var. gattii from the NT were analysed by random amplification of polymorphic deoxyribonucleic acid (RAPD) and polymerase chain reaction 'fingerprinting'. Two isolates were assigned to RAPD profile VGI, previously established as the common RAPD profile. The remaining 7 were assigned to profile VGII; 6 of these isolates were recovered from individuals living in the 'Top End'. The results strongly support the existence of an alternative environmental niche for C. neoformans var. gattii, as all isolates from Eucalyptus spp. in Australia to date have been of RAPD profile VGI.

Cryptococcosis↗
PubMedDate not supplied

Determination of ionophores in the tissues of food animals by liquid chromatography.

A liquid chromatographic method for determining residues of ionophores in bovine, porcine, and avian tissues is described. Tissues were extracted with iso-octane-ethyl acetate and the extracts purified on silica solid-phase extraction columns. Monensin, narasin and salinomycin were detected by UV absorbance following post-column derivatization with vanillin, and lasalocid was detected underivatized using fluorescence. In muscle, kidney and fat, all drugs were determined from a single sample extract. In liver, a separate extraction was done to determine lasalocid. The detection limit for lasalocid, narasin and salinomycin was 5 ppb; for monensin it was 2 ppb. Average recoveries were: lasalocid-71.0%; monensin-94.3%; salinomycin-97.2%; narasin-94.1%.

Adipose Tissue↗
PubMedDate not supplied

Two mental status assessment methods: an evaluation.

Impairments in mental status following cataract extraction surgery appear to be a significant clinical problem in the elderly. Despite the prevalence and potential mortality and morbidity, these impairments are frequently undetected. The Mini-Mental State Examination and the Mental Status Questionnaire were evaluated in a population of elderly cataract surgery patients. Although either test can be used to evaluate mental status, the sensitivity and specificity of each must be validated with a larger, controlled sample. The Mental Status Questionnaire was easier to administer, did not appear to induce additional fatigue in patients, and the scores were unaffected by patients' motor and sensory deficits.

Aged↗
PubMedDate not supplied

Effective discharge preparation of elderly cataract day surgery patients.

Nurses should ensure that prior to discharge, cataract surgery patients acquire basic knowledge about the surgical procedure, postsurgical recovery, and safe, appropriate health-care practices during early convalescence. The Modified Knowledge Test may be a functional, easy to administer tool to assess and track patient's knowledge about their post-cataract surgery recovery and safe, appropriate health-care practices during the early convalescent period. Patients can acquire most of the requisite knowledge regarding cataract extraction surgery prior to hospitalization. Some patients require reinforcement or remedial health teaching during hospitalization.

Aged↗