Diagnosis of naturally occurring toxoplasmosis by bronchoalveolar lavage in a cat.

A 5-year-old cat presented with a history of fever and respiratory distress of 7 days' duration. The cat did not respond to initial symptomatic treatment. Through use of a bronchoalveolar lavage (BAL) technique, the diagnosis of toxoplasmosis was obtained rapidly without evidence of adverse effects to the cat. Antemortem diagnosis of naturally occurring active Toxoplasma gondii infection can be difficult in cats. Identification of organisms obtained by BAL may be beneficial in the diagnosis of feline toxoplasmosis.

Use of a prestorage leukoreduction filter effectively removes leukocytes from canine whole blood while preserving red blood cell viability.

Leukoreduction of blood products is a technique used to prevent leukocyte-induced transfusion reactions. Filters currently used for human blood products achieve at least a 99.9% reduction in leukocyte numbers per unit (450 mL) of blood. Goals of this study were to determine if a prestorage leukoreduction filter could effectively achieve leukoreduction of canine blood and to determine if viability of the leukoreduced red blood cell (RBC) product could be maintained after 35 days of storage. Blood collected from each dog was filtered through a leukoreduction filter at either room temperature or after cooling (4 degrees C) for 4 hours. Filtration efficacy was determined by measurement of pre- and postfiltration leukocyte counts. In vitro viability of RBCs was determined by comparing RBC adenosine triphosphate concentration and percent hemolysis before and after the storage period. In vivo viability of stored cells was determined using a biotin-streptavidin-phycoerythrin labeling technique and flow cytometry. Blood filtered within 30 minutes of collection versus blood filtered after cooling had mean reductions in leukocyte numbers of 88.90 and 99.99%, respectively. The mean ATP and hemoglobin concentrations from the in vitro analysis were comparable to those obtained in previously for canine RBC adequately stored for 35 days. The mean in vivo 24-hour survival of the stored RBC was 84.7%. The leukoreduction filter used did not adversely affect in vitro or in vivo viability of canine RBCs. The filter effectively removed leukocytes from blood, with maximal efficiency of filtration achieved with use of cooled blood.

Calcium oxalate stones in feline littermates.

Two feline littermates were diagnosed with calcium oxalate uroliths. Both had been maintained on a commercially available dry diet with reduced magnesium and urine acidifying properties. One female littermate was diagnosed by visualising the stones by radiographs while the second littermate, also female, became blocked when one of the uroliths lodged in the urethra. Two other, unrelated cats in the household, of similar age and raised under the same conditions, did not develop calcium oxalate uroliths.

A thermodynamic QSAR analysis of the polysubstrate monooxygenase responses to xenobiotic chemicals.

Empirical quantitative structure activity relationships (QSAR) predict risk from exposure to xenobiotic chemicals as a dependence of inverse concentration on oil-water partition and electronic structural factors. This is equivalent, term by term to standard kinetic molecular transition state theory. When this transformed version is applied to the behaviour of the polysubstrate monooxygenase (PSMO) enzyme system, the rate of unintended behaviour depends directly on only two electronic factors. One is negative dependence on the strength of the weakest carbon-hydrogen (C-H) bond, a factor common to both ionic and free radical mechanisms. The second is a strong negative dependence on the polarization of this bond towards positive charge on the carbon, a factor relevant to ionic reactions. The risk of unintended oxidation reactions, in contrast, depends directly on these two factors because as the rate of intended hydroxylation is inhibited by strong or polar C-H bonds, alternative essentially 'accidental' oxidations occur. These are shown to lead to several different disease end points depending on the ratio of C-H bond strength to polarity.

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part II. Standardization of the neuropathologic assessment of Alzheimer's disease.

The Neuropathology Task Force of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) has developed a practical and standardized neuropathology protocol for the postmortem assessment of dementia and control subjects. The protocol provides neuropathologic definitions of such terms as "definite Alzheimer's disease" (AD), "probable AD," "possible AD," and "normal brain" to indicate levels of diagnostic certainty, reduce subjective interpretation, and assure common language. To pretest the protocol, neuropathologists from 15 participating centers entered information on autopsy brains from 142 demented patients clinically diagnosed as probable AD and on eight nondemented patients. Eighty-four percent of the dementia cases fulfilled CERAD neuropathologic criteria for definite AD. As increasingly large numbers of prospectively studied dementia and control subjects are autopsied, the CERAD neuropathology protocol will help to refine diagnostic criteria, assess overlapping pathology, and lead to a better understanding of early subclinical changes of AD and normal aging.

A correlation of induced mixed-function oxidase specific activity to C-H bond strengths in partially chlorinated monocyclic hydrocarbons.

The nature of structure-function relationships between the mixed-function oxidase (MFO) system and certain chemically related xenobiotics has been studied. The total hepatic induction index has been modified and used to investigate whether the induction of hepatic MFO is primarily a response to molecular shape (entropic) or to the strength of specific carbon-hydrogen bond strength (enthalpic). Using both Sprague-Dawley male rats and ring doves (Streptopelia risoria) and testing with benzene, 1,2,4-trichlorobenzene, cyclohexane and gamma-1,2,3,4,5,6-hexachlorocyclohexane as both inducers and substrates, a response of the MFO system to substrate C-H bond strength has been found.

The relative induction of mixed-function oxidase specific activity to C-H and C-C1 bond strengths in polychlorinated derivatives of dibenzo-p-dioxin (PCDDs).

The structure-activity relationships between the mixed-function oxidase (MFO) system and six polychlorinated derivatives of dibenzo-p-dioxin (PCDDs) were studied using Sprague Dawley rats. The study was set up in accordance with previous work in these laboratories involving monocyclic hydrocarbons. Three possible mechanisms at the MFO active site are proposed. C-H bond hydroxylation in low chlorine substituted PCDDs, and probable expoxidation in the intermediate chlorinated species including 2378 tetrachlorodibenzodioxin. Benzo[a]pyrene activity induced by some PCDDs appears irrelevant to the desired metabolic result.

Factor invariance and the Life Satisfaction Index.

This investigation of the Life Satisfaction Index (LSI) supports findings by Hoyt and Creech (1983) that indicate Adams' (1969) proposed factor structure is not invariant across groups. Two reduced factor models, proposed by Hoyt and Creech and based on a subset of LSI items, were studied with our sample (two levels each of income and age, N = 791). Our work confirms that the Hoyt and Creech 8-item LSI reveals the more stable factor structure of those examined. In addition, we found that the 8-item index has adequate statistical power to be of benefit to those investigators looking at quantitative differences in life satisfaction, with reasonable assurance that older and/or higher-income individuals are interpreting the items in similar ways.

A total hepatic induction index of metabolism for lipophilic xenobiotics.

A model for monitoring the hepatic ability to metabolize lipophilic xenobiotics is proposed. By identifying the behaviour of the mixed-function oxidase system as the rate determining feature of the response, an index can be devised from three independent factors: (i) the rate of the catalyzed reaction at each enzyme site, (ii) the concentration of such enzyme sites per hepatocyte and (iii) the total number of active hepatocytes available. Use of the model was tested by administering an acute oral dose of 1,2-benzanthracene to Sprague-Dawley rats. The above factors were measured in practical terms, these being (i) enzyme activity per time per mg protein, (ii) the concentration of enzyme per unit microsomal protein as well as the concentration of microsomal protein per unit liver weight and (iii) ratio of liver weight to body weight. After statistical analysis, it was found that each factor obeyed a different response curve characterized by a different ratio of growth to decay exponents. The product of these four measurable and physiologically discrete phenomena at any dose is the Total Hepatic Induction index. Together, the parameters that make up our model provide a means for inter- and intra-species comparisons as a response to various chemicals.

Attitudinal versus ecological approaches to the characterization of institutional treatment environments.

The relational and discriminative properties of attitudinal and ecological measures of environments were examined within the context of a state hospital for mentally retarted clients. Three hypotheses were advanced, and the results gave substantial support for one of these and partial support for a second: (a) that the correlations between attitudinal and ecological measures should not differ significantly from zero, and (b) that differences among hospital treatment programs and living units should be reflected in ecological but not in attitudinal measures. However, the results did not provide clear confirmation for a third hypothesis: that differences among staff demographic characteristics and employment history should be reflected in attitudinal but not in ecological measures. It was suggested that these background variables may not be appropriate measures of personality-linked attributes.

Factor structure of the SREB Attendant Opinion Scale.

A factor analysis of the SREB (Southern Regional Education Board) Attendant Opinion Scale was performed, based on the responses of 105 subjects. The results were very similar to those reported by the authors of the scale. Four factors were interpreted as relating to job dissatisfaction, maintenance of the rights of residents, belief in making residents conform to moral standards, and authoritarianism. The scale appears to be a promising instrument for evaluating attendants' attitudes.

Comparison of two sets of Piagetian scales with severely and profoundly retarded children.

Corman and Excalona's (1969) scales for Object Permanence and Spatial Relationships and the corresponding scales of Uzgiris and Hunt (1975) were administered to 64 severely and prfoundly retarded children. Most of the findings applied equally to both sets of scales: the scoring reliability was very high; the total scores did not vary as a function of subject characteristics (except IQ) or testing conditions; differences in the difficulty of the items did not correspond closely to those reported for nonretarded infants, and the scalability of the items was much lower. Less time was required to administer the two scales constructed by Uzgiris and Hunt, but their Object Permanence scale showed a pronounced ceiling effect and the internal consistency of their Spatial Relationships scale was unacceptably low.