The right touch. Support surfaces can pamper skin--and your budget.
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Beds↗
Biomedical subjects
C Powers
Publications and source records attributed to C Powers.
Primary liver neoplasms: MR imaging with pathologic correlation.
Magnetic resonance (MR) imaging is a powerful tool in the evaluation of primary liver neoplasms. Determination of tumor extent and tissue characterization is provided with standard spin-echo T1- and T2-weighted imaging and is enhanced by the application of advanced sequences such as gradient-echo, fast spin-echo, and fat suppression techniques. Intravenously administered contrast agents, such as gadopentetate dimeglumine and superparamagnetic iron oxide, provide additional opportunities for lesion characterization. Knowledge of the underlying gross and microscopic pathologic features of primary hepatic neoplasms leads to a better understanding of their often complicated MR imaging appearances. The authors correlate the key pathologic features with the most significant MR imaging findings of primary benign and malignant liver neoplasms, including hemangioma, focal nodular hyperplasia, hepatocellular adenoma, infantile hemangioendothelioma, mesenchymal hamartoma, hepatocellular carcinoma, fibrolamellar carcinoma, intrahepatic cholangiocarcinoma, biliary cystadenoma and cystadenocarcinoma, angiosarcoma, hepatoblastoma, and undifferentiated embryonal sarcoma.
Adenoma, Liver Cell↗
Diagnosis and natural history of extramammary tumors metastatic to the breast.
BACKGROUND: In patients with known extramammary malignancies, metastatic disease should be considered in the differential diagnosis of a breast mass. STUDY DESIGN: Retrospective review. RESULTS: From January 1, 1980 to December 31, 1992, nine women (ages 25 to 67 years) were identified with breast masses, the biopsies of which proved to be metastatic from other sites. All patients presented with palpable breast masses. Mammograms were obtained in five patients; all demonstrated the palpable abnormality. Two of three mammograms showing multiple nodules were evaluated as suggestive of benign disease. In three patients, breast metastases were the presenting symptom of an occult primary tumor. The remaining six patients were diagnosed with metastatic disease in the breast from ten months to 15 years after the initial diagnosis (mean of 5.5 years) of an extramammary malignancy. One-half of the patients presented five or more years after the initial diagnosis. Breast metastases were associated with disseminated metastatic disease in eight of the nine patients. Six patients died after a mean interval of 8.2 months (range of 3.5 to 35 months) from diagnosis of breast metastases. One patient was unavailable for follow-up evaluation and is presumed dead. CONCLUSIONS: Metastatic disease should be considered in the differential diagnosis of a palpable breast mass, particularly if there is a history of extramammary malignancy. The presence of multiple or bilateral well-circumscribed nodules may suggest a benign process on mammography. Breast metastasis is usually indicative of diffuse metastatic disease and a poor prognosis. Biopsy and careful review of previous pathologic material assures prompt treatment and avoids an unnecessary radical operation.
Adult↗
Changing clinical picture of mammary hamartoma.
During a 6-year period, we identified 12 patients (age range: 16 to 72 years) with a histologic or mammographic diagnosis of mammary hamartoma. The lesion was found in 9 of 441 open breast biopsy specimens (2%) and was identified radiographically in 5 of 8,122 mammographic examinations (less than 1%). Two groups of patients were identified. Three patients under 30 years of age underwent the excision of small palpable lesions found on pathologic examination to be mammary hamartomas (group I). In nine patients over age 30, masses were identified or confirmed on mammography (group II). Five lesions showed the classic mammographic appearance of a mammary hamartoma (a circumscribed tumor of mixed soft tissue and fatty density), and the other four were indeterminate. Presentation in these older women who had a relatively high incidence of atypical mammographic findings mandates that biopsy be performed.
Adolescent↗
Alveolar macrophage surface carbohydrate expression is altered in interstitial lung disease as determined by lectin-binding profiles.
Cell-surface-associated glycoconjugates play important roles in cellular functions such as antigen presentation and cell adhesion, functions that may be modulated in patients with interstitial lung disease. Because carbohydrate residues can be recognized by specific lectins, we designed our study to establish baseline data for bronchoalveolar-lavage-derived cells from normal volunteers and to compare the lectin-binding properties of these cells with cells recovered from patients presenting with interstitial lung disease. Cells were obtained from patients with idiopathic pulmonary fibrosis (n = 10), patients with sarcoidosis (n = 20), and patients receiving amiodarone without evidence of clinical lung disease (n = 10) as well as from normal volunteers (n = 8). To determine the pattern of cell-surface glycoconjugate expression on alveolar macrophages (AM), we used a panel of 21 fluorochrome-coupled plant lectins and employed flow cytometry to determine their binding to AM. The labeling profiles of AM were found to be highly reproducible for normal subjects. At the lectin concentrations used for this study, some lectins showed very little binding to AM and some displayed intermediate binding, but the majority of the lectins labeled nearly all AM in samples. Fluorescence intensity varied characteristically for cells labeled with different lectins, providing further refinement and permitting discrimination beyond that provided by data restricted to percent of labeling. AM from patients with interstitial lung disease showed increased binding for the plant-derived lectins PNA, UEA-I, BSL-I, VVL, and SJA compared with AM from normal subjects, being most augmented for AM from patients with idiopathic pulmonary fibrosis. Because peripheral blood monocytes from normal subjects show a higher percentage of labeling with PNA, UEA-I, SJA, and BSL-I than did AM, the increased expression of binding sites for these four lectins by AM from patients with interstitial lung disease may reflect the influx of immature blood monocytes and/or the emergence of a proinflammatory macrophage phenotype. This study demonstrated heterogeneous expression of surface carbohydrate residues by AM and blood monocytes from normal subjects and alterations in carbohydrate receptor expression in interstitial lung disease. Lectin-binding properties may prove useful, therefore, in the evaluation of mononuclear phagocyte populations in interstitial lung disease, especially by the identification of functional subsets and/or changed activation states.
Adolescent↗
Effects of interferons beta or gamma on neopterin biosynthesis and tryptophan degradation by human alveolar macrophages in vitro: synergy with lipopolysaccharide.
Interferons can induce neopterin biosynthesis and tryptophan degradation in monocytic cells. Indoleamine 2,3-dioxygenase (IDO), an inducible cellular enzyme, metabolizes tryptophan to N-formyl-L-kynurenine. Tryptophan degradation has been linked to interferon-mediated inhibition of replication by intracellular pathogens and inhibition of cancer cell proliferation. We evaluated the ability of the recombinant human interferons beta ser and gamma to stimulate neopterin production and tryptophan degradation in vitro by alveolar macrophages (AM) obtained from normal volunteers by bronchoalveolar lavage. Additionally, because other biologic response modifiers such as lipopolysaccharide (LPS) can also stimulate monocytic cells to produce increased amounts of neopterin and degrade tryptophan, we evaluated the effects of LPS on interferon-induced neopterin production and tryptophan degradation by AM. Both interferon-gamma (IFN-gamma) and interferon-beta (IFN-beta) induced neopterin production and tryptophan degradation by AM with corresponding inhibition of intracellular replication by Chlamydia psittaci in AM, but IFN-gamma was a more potent inducer of these responses than IFN-beta. LPS enhanced neopterin production and tryptophan degradation by interferon-exposed cells. This effect was particularly evident at lower concentrations of interferon, and LPS synergy was more pronounced with IFN-beta than IFN-gamma. Concentrations of LPS that alone had no stimulatory effect on tryptophan degradation synergistically enhanced the induction of IDO activity by lower concentrations of interferon. These studies suggest that IFN-gamma stimulates human AM to produce neopterin and degrade tryptophan more potently than IFN-beta, and that low concentrations of LPS can synergistically enhance such effects of interferons on tissue macrophage metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Diagnostic efficacy of digitized images vs plain films: a study of the joints of the fingers.
Four hundred fifteen finger joints from 30 patients were evaluated for the presence of joint-space erosion, narrowing, and degenerative spurring on plain films, low-resolution digitized images (1024 x 840 bytes x 12 bit matrix), and high-resolution digitized images (2048 x 1680 bytes x 12 bit matrix). Three hundred four joints were abnormal. Low- and high-resolution digital images were displayed on a 1K x 1K monitor with the ability to change level, window, orientation, and brightness. Five radiologists interpreted images. The presence or absence of each abnormality was determined by consensus of two skeletal radiologists who did not otherwise participate in the study. Receiver-operating-characteristic analysis was used to obtain an area and a true-positive rate at a 0.10 false-positive rate for each interpreter. Randomized block analysis of variance with interpreters as blocks was used to compare areas and true-positive rates among imaging techniques for each type of abnormality; no statistically significant differences were found. In conclusion, the efficacy of display of digitized images on high- and low-resolution modes is not significantly different from that of plain films in the detection of erosions, joint-space narrowing, or degenerative spurring in small joints of the hands.
Analysis of Variance↗
Priming of human alveolar macrophages and blood monocytes for superoxide anion release by interferons and lipopolysaccharide.
Biological agents such as the interferons (IFNs) or lipopolysaccharides (LPSs) can prime phagocytic cells to generate increased amounts of oxygen metabolites upon exposure to various stimuli. The priming of human peripheral blood monocytes and alveolar macrophages (AM) by recombinant IFN-beta ser (rIFN-beta ser) and rIFN-gamma for an enhanced respiratory burst was compared. Both rIFN-beta ser and rIFN-gamma increased phorbol myristate acetate-stimulated superoxide anion generation by AM in a dose-dependent fashion. rIFN-beta ser was capable of priming AM for an enhanced superoxide anion release nearly as well as rIFN-gamma. In contrast, rIFN-beta ser was much less effective as a priming agent for monocytes when compared to either its effect on AM or to the priming effect of rIFN-gamma on monocytes. The respiratory burst of IFN-exposed AM was not inhibited by co-incubation with low concentrations of LPS. However, the ability of IFN to augment superoxide anion release by cells simultaneously exposed to LPS in comparison to superoxide anion generation by cells exposed to LPS only was attenuated.
Adult↗
Pathogenic properties of Edwardsiella species.
The pathogenic characteristics of 35 Edwardsiella strains from clinical and environmental sources were investigated. Overall, most Edwardsiella tarda strains were invasive in HEp-2 cell monolayers, produced a cell-associated hemolysin and siderophores, and bound Congo red; many strains also expressed mannose-resistant hemagglutination against guinea pig erythrocytes. Edwardsiella hoshinae strains bound Congo red and were variable in their invasive and hemolytic capabilities while Edwardsiella ictaluri strains did not produce either factor; neither E. hoshinae nor E. ictaluri expressed mannose-resistant hemagglutination nor elaborated siderophores under the tested conditions. Selected strains of each species tested for mouse lethality indicated strain variability in pathogenic potential, with E. tarda strains being the most virulent; 50% lethal doses in individual strains did not correlate with plasmid content, chemotactic motility, serum resistance, or expression of selected enzyme activities. The results suggest some potential important differences in pathogenic properties that may help explain their environmental distribution and ability to cause disease in humans.
Animals↗
Choice of anesthetic technique for needle localized breast biopsy.
General anesthesia has been recommended to increase the accuracy and safety of needle localized biopsy (NLB). The authors' NLB experience was reviewed to determine whether the method of anesthesia affected accuracy, yield, complication rate, or cost. All biopsies were performed in a standard operating room using either local anesthesia (Group 1, n = 14), local anesthesia with an anesthesiologist present (Group 2, n = 14), or general anesthesia (Group 3, n = 10). The mean operative times were 54, 59, and 56 minutes for Groups 1, 2, and 3, respectively. In groups 1 and 2, 100 per cent of the specimen radiographs showed the target lesion had been excised, although one biopsy was indeterminate. Among Group 3 two target lesions could not be identified on specimen radiographs and one was indeterminate. There was one malignancy in Group 1 compared with four malignancies in Group 2 and two in Group 3. The average hospital bill was $1,172 for Group 1, $1,418 for Group 2, and $1,488 for Group 3. Anesthesiologists' fees added an additional $224 to Groups 2 and 3. NLB can be performed using local anesthesia without sacrificing accuracy or yield, increasing operative time, or increasing complication rate; the cost is significantly less than with general anesthesia.
Adult↗
Epidemiologic investigations of Yersinia enterocolitica and related species: sources, frequency, and serogroup distribution.
During an 11-year period (1978 to 1989), over 300 strains of Yersinia spp. (excluding Y. pestis and Y. pseudotuberculosis) were recovered from a variety of gastrointestinal and extraintestinal sites in patients in California. Over the 11-year period, Y. enterocolitica serogroup O:3 predominated, although a shift in the relative frequency of this serogroup was observed during this interval, increasing dramatically during the years 1984 to 1989. Of the remaining Y. enterocolitica isolates, over 40% were identified as belonging to serogroups generally considered to be nonpathogenic, although many of these isolates were recovered in association with milder cases of gastroenteritis. The results suggest a changing and expanding spectrum of Y. enterocolitica serogroups associated with various gastrointestinal and systemic infections.
California↗
Carnitine metabolites in infants with cystic fibrosis.
Decreased acylcarnitine levels have been found in cord blood of CF infants compared to siblings and controls. We therefore measured carnitine metabolites in blood and urine in 15 newly diagnosed (average age 4 mos) CF infants and followed the levels for one year. No consistent abnormality in carnitine status was detected in newly diagnosed infants; levels normalized at one year after therapy with predigested formula containing carnitine supplements. This data does not provide support for a primary abnormality of carnitine metabolism in CF.
Age Factors↗
Emergence of a restricted bioserovar of Vibrio parahaemolyticus as the predominant cause of Vibrio-associated gastroenteritis on the West Coast of the United States and Mexico.
Examination of 45 human fecal isolates of Vibrio parahaemolyticus revealed the emergence of an unusual bioserovar (O4:K12, urease positive) associated with cases of gastroenteritis which appear to be domestically acquired on the West Coast of the United States and Mexico.
California↗
Current perspectives on the epidemiology and pathogenesis of clinically significant Vibrio spp.
Recent taxonomic advances have now implicated several different Vibrio species as human pathogens. While the most common clinical presentation of Vibrio infection continues to be gastroenteritis, an increasing number of extraintestinal infections are being reported, particularly in immunocompromised individuals. Detection of Vibrio infections requires a good clinical history and the use of appropriate isolation and identification procedures by the laboratory to confirm illnesses attributed to Vibrio species. Except for Vibrio cholerae O1 and Vibrio parahaemolyticus, there is little direct evidence linking the production of a myriad of cell-associated or extracellular factors produced by each species with human disease and pathogenesis. Many questions regarding pathogenic Vibrio species remain unanswered, including their frequency and distribution in environmental specimens (water, shellfish), infective doses, virulence potential of individual isolates, and markers associated with such strains.
Epidemiologic Methods↗
Effect on lens regeneration of implantation of spinal ganglia into the eyes of the newt, Notophthalmus.
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Animals↗
Immunofluorescent identification of Salmonella typhi during a typhoid outbreak.
Immunofluorescence and conventional bacteriological methods were compared for their ability to detect Salmonella typhi in 134 fecal specimens from 105 individuals associated with an outbreak of typhoid fever. Smears prepared from untreated fecal material (direct method) and after a preliminary incubation in selenite F broth (delayed method) were tested with an anti-Vi serum conjugated with fluorescein isothiocyanate. The delayed method was more sensitive than the direct method in detecting S. typhi. The delayed method was positive in 40 of 41 patients positive by culture methods, but gave positive or questionable reactions in 11 presumably uninfected individuals. The fluorescent-antibody test employing a Vi conjugate is a satisfactory screening procedure for detecting S. typhi, but all positives must be confirmed bacteriologically.
Bacteriological Techniques↗
A new Salmonella Serotype: Salmonella Los Angeles.
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California↗
MR demonstration of a cystic pheochromocytoma.
Cystic pheochromocytoma is a rare tumor of the adrenal gland that can pose a diagnostic challenge. We report a case of a 14-year-old boy who had an adrenal lesion that appeared cystic by both sonography and CT, but that demonstrated hemorrhage into the lesion at MR imaging, and proved to be a cystic pheochromocytoma. We emphasize the importance of considering the diagnosis of pheochromocytoma when faced with a cystic lesion of the adrenal gland.
Adolescent↗