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Biomedical subjects

R L West

Publications and source records attributed to R L West.

At least 55 records · Page 3Linked to original sources
PubMed1989

Bronchoalveolar lavage in the diagnosis of lipoid pneumonia.

Lipoid pneumonia (LP) is an uncommon entity with the characteristic radiographic features and histologic findings of alveoli filled with vacuolated, lipid-laden histiocytes. We questioned whether bronchoalveolar lavage (BAL) could be useful in the confirmation of LP. We examined lipid stains (oil-red O) in BAL specimens from 18 cases, representing a variety of pulmonary disease states, and compared them with an index case of confirmed LP. The index case of LP had a history of chronic intranasal use of mentholated petrolatum with subsequent x-ray findings of progressive air bronchograms. Positive histochemical confirmation (oil-red O) performed on frozen sections of transbronchial lung biopsy was obtained. Eleven of the non-LP cases had no intracellular staining of BAL macrophages with oil-red O stain, whereas the index case of LP exhibited markedly positive intracytoplasmic staining of macrophages for lipid. The remaining seven cases showed minimal to mild lipid staining with only one other case having moderate staining. This study demonstrates that BAL macrophages from patients with a variety of pulmonary states and without suspected LP do not demonstrate significant staining for intracellular lipids, in contrast with the expected strong positivity of LP. Lipid staining of BAL specimens, although not entirely specific, may be a preferred method for confirming the diagnosis of LP, thereby avoiding more invasive procedures.

Adult↗
PubMed1987

Carcass and meat quality characteristics and backfat fatty acid composition of swine as affected by the consumption of peanuts remaining in the field after harvest.

Carcass composition, meat quality characteristics and changes in backfat fatty acid composition of swine that were allowed to obtain part or all of their weight gain during the growing-finishing period from gleaning peanuts remaining in the field after harvest were evaluated. Thirty-six cross-bred pigs (18 barrows, 18 gilts) were allotted evenly among the following six treatments: 1) fed a corn-soybean meal-based diet (C) from 26 to 104 kg (CCC); 2) gleaned peanuts (P) from 26 to 102 kg (PPP); 3) C from 26 to 78 kg and P from 78 to 103 kg (CCP); 4) P from 26 to 55 kg and C from 55 to 105 kg (PCC); 5) C from 26 to 56 kg and P from 56 to 103 kg (CCP); 6) P from 26 to 79 kg and C from 79 to 106 kg (PPC). Carcasses from all treatment groups were similar in composition. Carcass fat of pigs in CPP, PPC and, in particular, PPP groups was softer than that from pigs in CCC, CCP and PCC groups. Ratio of unsaturated to saturated fatty acids in backfat increased in proportion to the amount of weight gained while pigs gleaned peanuts. Loins from pigs in the PPP and CPP treatment groups received lower marbling scores than those from the CCC group, but the fat content of the loin was not affected by treatment. No differences were detected between treatment groups in shear force values or sensory panel attributes of broiled loin chops, or in thiobarbituric acid values of vacuum packaged loin sections frozen for 4 mo.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1986

The role of fine-needle aspiration biopsy in the rapid diagnosis and management of thyroid neoplasm.

This report describes our 5-year experience with fine-needle aspiration (FNA) biopsy of the thyroid in a 560-bed teaching hospital. Three hundred nine FNA biopsies were performed primarily by one endocrinologist and interpreted by several pathologists. Analysis of the data reveals the sensitivity of the procedure is 93%, specificity is 95.1%, and the positive and negative predictive values are 88.9% and 96.5%, respectively. This data confirms the diagnostic accuracy of FNA biopsy. Complications were seen in 6 of 309 cases (1.9%) and were relatively mild. Nearly 75% of the cases in the series were cytologically diagnosed as nonneoplastic. Fine-needle aspiration biopsy identified 19.4% of the cases needing surgery, of which 72% had neoplastic nodules, confirming the selection role of the procedure. The management of thyroid nodules is discussed and a selective review of the FNA literature is presented. The authors believe that our experience rebuts the argument that special referral centers are needed to interpret the cytologic material. Several well trained surgical pathologists can become proficient in interpreting the FNA biopsies without significant loss in accuracy, and thereby render a definite diagnosis in the vast majority of the cases. Accordingly, the authors recommend FNA of the thyroid as the initial diagnostic test in the evaluation of thyroid nodules.

Adenocarcinoma↗
PubMed1986

Ultrastructural and metabolic changes associated with reproductive tract atrophy and adiposity in diabetic female mice.

The effect of progressive, diabetes-associated adiposity on reproductive tract structure and function was examined in 4- to 16-week-old C57BL/KsJ, control (+/?) and diabetic (db/db) mice. Uterine and ovarian tissues were analyzed by transmission electron microscopy for ultrastructural changes associated with increased intracellular lipid accumulation. In addition, the same tissues were analyzed for changes in activity of tissue lipoprotein lipase, an enzyme that hydrolyzes lipoprotein-associated triacylglycerols and supports the cellular uptake and storage of free fatty acids. Between 8 and 16 weeks of age, intracellular lipid deposits increased dramatically in the ovarian granulosa, thecal and stromal cell populations, as well as in the uterine epithelium, of diabetic mice compared to controls. By 16 weeks of age, the lipid deposits essentially occupied the entire cytoplasmic area of both the ovarian and uterine cell types in diabetics. The basal lamina underlying the uterine epithelium was expanded in the diabetics relative to controls, and the hyperglycemic condition induced an observable increase in endometrial intercellular space that was occupied by a hyaline type of ground substance of unknown composition and origin. In association with these structural changes, both ovarian and uterine lipase activities were greatly increased in the db/db mice compared with controls. These data suggest that the structural adiposity and functional decline in reproductive tract condition of the db/db mutants are related to the enhanced cellular lipid deposition observed in this species. These changes in structural and metabolic parameters are related to the reproductive incompetence characteristic of this murine model.

Animals↗
PubMed1986

Chordoma: diagnosis by fine-needle aspiration biopsy with histologic, immunocytochemical, and ultrastructural confirmation.

Five cases of chordoma, diagnosed by fine-needle aspiration (FNA) biopsy, are presented. Four cases were histologically confirmed, and in one, immunocytochemical and ultrastructural studies were performed on both the aspirate and tissue specimen. Four cases presented as sacral masses, while in the fifth case, a destructive lesion of the clivus extended into the soft tissues of the lateral neck. A spectrum of cytomorphologic features was encountered including the presence of abundant microtissue fragments and cells in a dissociate pattern, often with abundant metachromatic extracellular matrix. Stellate and cuboidal cells often contained intracytoplasmic vacuoles of varying sizes. Intranuclear inclusions, mitotic figures, and anisonucleosis were prominent features of several cases. Immunoperoxidase studies on a single case demonstrated cytoplasmic staining for low- and high-molecular-weight cytokeratins, vimentin, and epithelial membrane antigen, while glial fibrillary acidic protein and carcinoembryonic antigen were negative. Ultrastructural features included the presence of mitochondrial endoplasmic reticulum complexes, occasional desmosome-like junctions, and abundant extracellular matrix adherent to the tumor cells. We believe the cytomorphologic findings are characteristic and, when taken in concert with immunocytochemical and ultrastructural studies, allow differentiation of chordoma from other primary or metastatic neoplasms occurring in bone. As demonstrated in our series, chordoma is often an unsuspected diagnosis. We believe that FNA biopsy of these lesions can lead to a correct preoperative diagnosis and may also be utilized to document recurrence and thus facilitate the evaluation and management of patients with these lesions.

Aged↗
PubMed1986

Effects of slaughter weight and carcass electrical stimulation on the quality and palatability of beef from young purebred bulls.

Seventy-eight purebred Angus and Brahman bulls (10 to 18 mo at slaughter) were used to determine the effects of slaughter weight (60, 80, 90 or 100% of the average mature-cow weight for the respective breed) and carcass electrical stimulation (500 V, 20 2-s impulses on the right side) on carcass and meat characteristics. Angus bulls grazed summer forage (millet) after weaning, while Brahman bulls were fed to stimulate gains achieved on forage by Angus bulls. Bulls were then placed in the feedlot for finishing to their designated slaughter weight (293, 381, 412 and 463 kg for Angus and 316, 420, 463 and 516 kg for Brahman). Coarse dark band formation and lean color problems normally associated with bullock carcasses were either eliminated or reduced by stimulation. Increasing slaughter weight from 60 to 90% was associated with an increase in panel tenderness scores for loin steaks. However, increasing slaughter weight from 90 to 100% little change was detected. On the other hand, shear values for loin steaks decreased with increasing slaughter weight. Stimulation increased the tenderness of loin steaks as determined by both panel scores and shear values, and of bottom round steaks (shear-force values). The data from this study suggest that meat from the bulls slaughtered at lighter weights was generally tough, but was improved when bulls were fed to heavier, yet acceptable weights. This research encourages implementation of electrical stimulation on carcasses from young bulls to improve quality-indicating factors.

Animals↗
PubMed1986

Growth and muscle development characteristics of purebred Angus and Brahman bulls.

Thirty-eight purebred bulls (10 to 17 mo of age) were used to determine the effects of breed (Angus or Brahman) and slaughter weight (60, 80, 90 or 100% of the average mature dam's weight for the respective breed) on growth and muscle development characteristics. Angus bulls grazed summer forage after weaning whereas Brahman bulls were fed to simulate gains achieved on forage by Angus. Bulls were then placed in a confinement feedlot for finishing to their appropriate slaughter weight (293, 369, 411, and 469 kg for Angus and 307, 427, 464 and 520 kg for Brahman). No major differences due to breed were found for predicted carcass composition. The LD muscle from Brahman bulls contained more total DNA (2.27 v. 1.19 g), more total protein (768.22 v. 593.59 g) and generally less total lipid (70.56 v. 101.26 g) when expressed on a total muscle (wet tissue) basis. The percentages and areas for all three muscle fiber types were not affected by breed. As carcass weight increased, muscle weights, total protein, lipid, protein:DNA and muscle fiber size for the three fiber types increased. Total DNA content increased only up to the 90% weight group and then leveled off. The percentage of alpha R fibers decreased while the percentage of alpha W fibers increased with increasing carcass weight. These data suggest that slaughtering animals based on a percentage of their dam's mature weight seems to be a practical method for making comparisons of animals on an equivalent compositional basis. Moreover, it appears that histochemical and biochemical evaluations of skeletal muscle can successfully identify what point in the growth cycle an animal is in.

Aging↗
PubMed1985

Morphometric analysis of medial basal hypothalamic neuronal degeneration in diabetes (db/db) mutant C57BL/KsJ mice: relation to age and hyperglycemia.

Age- and diabetes-related neuronal degenerative changes were morphometrically evaluated in the arcuate (ARC) and ventromedial (VMH) hypothalamic nuclei of control (+/?) and diabetic (db/db) C57BL/KsJ mice between 4 and 16 weeks of age. By 4 weeks of age, (db/db) mice exhibited marked obesity and hyperglycemia relative to controls. An increase in the population of degenerated ARC neurons was detected at 8 weeks of age in (db/db) mice relative to (+/?) animals. By 16 weeks of age, a significant increase in the number of degenerated VMH neurons in (db/db) mice was found, relative to controls. In addition, the neuronal density (neurons/mm2 area of nucleus) of both the ARC and VMH nuclei was found to be depressed in (db/db) mice, relative to controls, by 16 weeks of age. These data suggest that the normal degenerative loss of ARC and VMH neurons that occurs with age in normal mice is enhanced in the (db/db) mouse. These findings suggest that a functional alteration in hypothalamic nuclei which are recognized to modulate autonomic, pancreatic and pituitary activity may be associated with the onset or expression of the diabetic condition in the C57BL/KsJ (db/db) mouse.

Age Factors↗
PubMed1985

The systematic use of semantic and acoustic processing by younger and older adults.

To examine age differences in semantic and acoustic processing, 80 older and 80 younger adults participated in an incidental learning study. The study compared free recall and semantic and acoustic cued recall performance after five orienting conditions. The younger adults performed better than the older adults, especially after acoustic orienting. Encoding specificity effects occurred at both age levels. The results indicated that both age groups performed better with semantic processing than acoustic processing, but that older adults relied on the semantic information far more than the younger adults.

Adult↗
PubMed1984

The link between memory performance, self-assessment, and affective status.

To investigate the relationship between memory performance, self-assessment of memory, and affective status, 67 elderly females were administered a self-assessment memory questionnaire and multiple measures of affect and laboratory memory tet performance. Canonical correlations indicated that the memory performance scores were not related to the affective measures nor to the scales of self-assessed memory ability. Affective status and self-assessment of memory skill were related, suggesting that investigations of memory performance which rely on self-assessment should also measure affective status.

Affect↗
PubMed1983

Age differences in cued recall and recognition under varying encoding and retrieval conditions.

This experiment investigated the role of the encoding-retrieval relationship in adult age differences in memory. To determine the optimal encoding-retrieval conditions for adults of different ages, young, middle-aged, and older adults were given a semantic or acoustic orienting task, followed by semantic and acoustic recognition tests or semantic and acoustic cued recall tests. As predicted, the results demonstrated the importance of similar encoding and retrieval conditions at all ages, especially with semantic processing. Age differences were reduced on the recognition test and when semantic encoding was combined with a semantic cue test at retrieval. It was concluded that acoustic processing is not as effective as semantic processing for older or younger adults, and that effective use of semantic processing by older adults depends on constrained task conditions. These conditions include congruent semantic orienting questions that specify precise meanings for each target item, and retrieval cues that match the information in the orienting questions.

Adult↗
PubMed1979

Effects of perceptual training on the salience of information in a recall problem.

Kindergarten children were given a salience-assessment task to determine each child's salience hierarchy for the dimensions of form, color, and position. The children were then assigned to either a control condition or one of 3 conditions providing different types of perceptual training with the child's least salient dimension. In a subsequent location recall task, children in all 3 training groups made significantly fewer errors recalling values of their least salient dimension than children in the control group. The results indicated that perceptual exposure alone was sufficient to increase the perceptual salience of the least salient dimension and its subsequent conceptual evaluation.

Child↗