Underutilization of the Papanicolaou smear in human immunodeficiency virus-positive women.
Explore the source record for details and available documents.
Community Health Services↗
Biomedical subjects
A E Walts
Publications and source records attributed to A E Walts.
Pulmonary cysticercus.
Cysticercus cellulosae, the encysted larva of Taenia solium, is reported in a solitary granulomatous lesion excised from the lung of a 61-year-old woman from Thailand. No extrapulmonary signs of cysticercosis were manifest preoperatively, and the diagnosis was not suspected clinically. Pulmonary cysticercus is rarely diagnosed histologically. When unaccompanied by extrapulmonary disease, a single cysticercus lung lesion may be clinically and radiologically indistinguishable from other granulomata and malignancy.
Animals↗
Neural networks as an aid in the diagnosis of lymphocyte-rich effusions.
Neural network (NN) technology was applied to digital image analysis data for 112 Papanicolaou-fixed and -stained smears of lymphocyte-rich effusions (LREs). The smears were analyzed with an inexpensive image analysis system assembled in our laboratory. Several models were developed using backpropagation NN development software in an effort to optimize classification of the LREs as reactive lymphocytosis or malignant lymphoma and to analyze the effects of various parameters on classification rates. The greatest specificity and sensitivity of LRE classification were achieved with NN models that consisted of 7 input neurons, including 5 morphometric and 2 densitometric variables, 10 hidden-layer neurons and 1 output neuron. This NN architecture with a sigmoidal transfer function provided a true cross-validation rate of 89.3% of testing data, with a sensitivity of 76.9%, specificity of 93.0% and shrinkage of 10.7%. The same NN architecture with a step transfer function provided a true cross-validation rate of 95.3%, sensitivity of 85.7%, specificity of 97.6% and shrinkage of 0%. The effects of various parameters, such as network size, shrinkage and ratio of sample size to input layer size, on NN accuracy are discussed.
Ascitic Fluid↗
Lymphoid-rich effusions. Diagnosis by morphometry using the CAS 200 System.
Lymphoid-rich effusions frequently present diagnostic problems in clinical cytology. In the authors' previous studies, most lymphoid-rich effusions had been correctly classified as benign lymphocytosis or malignant lymphoma by an experimental computerized interactive morphometry system, in which randomly selected lymphoid nuclear profile images were measured in Papanicolaou fixed and stained cytospin smears. The present study used the CAS 200 System and criteria from the previously described rule-based expert system to classify similar preparations of 134 lymphoid rich pleural, peritoneal, and pericardial effusions (90 benign lymphocytoses, 36 malignant lymphomas, and 8 chronic lymphocytic leukemias). A total of 98.9% of the benign lymphocytoses and 88.9% of the malignant lymphomas were correctly classified (predictive values of correct diagnoses 95.7% and 97.3%, respectively). Chronic lymphocytic leukemias could not be distinguished from benign lymphocytoses by nuclear profile areas. Optical density histograms of benign, lymphomatous, and chronic lymphocytic leukemias effusions are described. Advantages and limitations of image analysis and immunocytochemistry are discussed.
Ascitic Fluid↗
Is immunoreactivity for p53 useful in distinguishing benign from malignant effusions? Localization of p53 gene product in benign mesothelial and adenocarcinoma cells.
p53 protein is a "natural tumor suppressor" that plays an important role in controlling cell proliferation. Alterations resulting in overexpression of this gene product have been described in a wide variety of human malignancies. We utilize two commercially prepared monoclonal antibodies to assess the potential role of immunoreactivity for p53 protein in distinguishing benign mesothelial from adenocarcinoma cells in effusion smears. p53 protein was detected in adenocarcinoma cells in 78% of the malignant fluids studied. Benign mesothelial cells in 14% of these fluids and in 73% of the benign fluids also stained for p53. Differences in staining were observed with the Bp-53-12-1 and the 1801 antibodies. Intensity, intracellular distribution, and frequency of immunoreactivity within each cell population are described. Observations are discussed in relation to sensitivity and specificity of the monoclonal antibodies for different configurational forms of p53 protein, configurational modifications of p53 protein during the cell cycle, and diagnostic evaluation of effusion smears for the presence of malignant cells. Immunoreactivity for p53 does not correlate with site of primary tumor. Although overexpression of p53 is more frequent in adenocarcinoma cells than in reactive mesothelial cells, p53 protein overexpression is not necessarily indicative of malignancy.
Adenocarcinoma↗
Cerebrospinal fluid cytology: selected issues.
Explore the source record for details and available documents.
Biopsy, Needle↗
Pulmonary cytology in lung transplant recipients: recent trends in laboratory utilization.
The value of bronchoscopy for the diagnosis of rejection and opportunistic infection in lung transplant recipients is controversial. We review our experience with pulmonary cytology obtained from 10 lung transplant recipients during the first 15 mos of the transplantation program at Cedars-Sinai Medical Center and compare the efficacy of pulmonary cytology for the diagnosis of opportunistic infectious agents with that of histology and microbiology. Our study encompasses 1,465 post-transplant days during which 70 bronchoscopies were performed yielding 94 cytologic specimens (44 bronchial washes, 25 bronchial brushings, and 25 bronchoalveolar lavages) and 55 transbronchial biopsies. The major advantages of cytology in this setting are short turn around time and high specificity for nonbacterial agents. All of the patients experienced episodes of bacterial pneumonia as well as fungal and viral infections. None developed Pneumocystis carinii infection during the study period. Simultaneous and concurrent infections were diagnosed. The initial diagnosis of bacterial pneumonia and herpes simplex virus preceded the diagnosis of cytomegalovirus; the former infections tended to persist and/or recur. Cytology was more effective than histology in establishing the diagnosis of Candida sp. and herpes simplex virus, while histology was more effective in establishing the diagnosis of cytomegalovirus. Increased numbers of polymorphonuclear cells did not constitute a consistent finding in cytologic or histologic samples during episodes of bacterial infection; cultures were most sensitive for detection of bacterial infection. Histochemical and immunohistochemical stains as well as in situ hybridization studies confirmed diagnoses rendered on routine Papanicolaou and hematoxylin and eosin stained material but did not provide additional diagnoses.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Pneumocystis carinii in FNA of the thyroid.
We report the diagnosis of Pneumocystis carinii (PC) in a fine-needle aspirate (FNA) from the thyroid of a human immunodeficiency virus infected (HIV+) male receiving aerosolized pentamidine as prophylaxis for Pneumocystis carinii pneumonia (PCP). The clinical diagnosis prior to FNA was multinodular goiter. The patient did not have pulmonary symptoms nor previous diagnosis of PCP at the time of the aspirate diagnosis. Recently, extrapulmonary Pneumocystis carinii (EPC) has been reported with increasing frequency in HIV+ patients receiving prophylactic aerosolized pentamidine. Awareness of extrapulmonary presentations of Pneumocystis carinii infection is a prerequisite for accurate cytologic diagnosis.
Adult↗
The severity of atherosclerosis at sites of plaque rupture with occlusive thrombosis in saphenous vein coronary artery bypass grafts.
Atherosclerotic plaque rupture with superimposed thrombosis is recognized as the lesion causing late, acute, thrombotic saphenous vein coronary artery bypass graft (CABG) occlusion. To determine the severity of atherosclerosis at the site of plaque rupture, 68 saphenous vein CABGs removed at the time of reoperation or at autopsy were studied. The study population consisted of 57 men, 64 +/- 9 years old, and nine women, 70 +/- 10 years old. The duration of graft implantation was 7.9 +/- 2.7 years (mean +/- S.D.). All CABGs were dissected from the hearts, fixed, decalcified, cut at 2 to 3 mm intervals, and processed routinely for histologic examination. A planimeter was used to measure total vessel, plaque, thrombus, and luminal cross-sectional areas at the site of plaque rupture with thrombosis in sections projected at 13.8 power magnification. At the site of atherosclerotic plaque rupture with superimposed thrombosis, the degree of stenosis due to plaque was: 90 +/- 11% for the right coronary artery grafts (n = 19); 94 +/- 7% for the left anterior descending artery grafts (n = 41), and 90 +/- 14% for the left circumflex artery (n = 8) grafts. Thus in saphenous vein CABGs, atherosclerotic plaque rupture with thrombosis usually occurs at sites of severe narrowing (mean = 93%) by preexisting atherosclerotic plaque.
Aged↗
Intracystic papillary carcinoma of the breast.
Explore the source record for details and available documents.
Aneuploidy↗
Diagnosis of malignant lymphoma in effusions from patients with AIDS by gene rearrangement.
Patients infected with human immunodeficiency virus are prone to a wide variety of lymphoproliferative disorders. In these patients the clinical presentation of malignant lymphoma often overlaps with that of benign lymphoid proliferations. Both may include lymphadenopathy, splenomegaly, blood and bone marrow dyscrasias, and lymphocyte-rich effusions. Because benign and malignant lymphocyte-rich effusions, as well as effusions from other malignancies, may contain large cells that resemble immunoblasts or Burkitt's cells, cytomorphologic characteristics alone are unreliable for definitive diagnosis of malignant lymphoma. Usual immunotyping panels using antibodies to B- and T-cell markers frequently fail to demonstrate cell lineage in lymphoma cells of patients with acquired immune deficiency syndrome (AIDS). The authors used gene rearrangement to confirm the diagnosis of malignant lymphoma in effusions from three patients with AIDS when routine cell marker studies failed to demonstrate cell lineage or clonality. Use of biotinylated probes eliminated the need for handling radioactive material and enabled performance of studies in a routine immunohistochemistry laboratory.
Acquired Immunodeficiency Syndrome↗
Computerized interactive morphometry. An expert system for the diagnosis of lymphoid-rich effusions.
The authors present experimental techniques for the diagnosis of malignant lymphoma and benign lymphocytosis in lymphoid-rich effusions with the use of an inexpensive microcomputer-based video system for computerized interactive morphometry (CIM). Lymphoid cells were randomly selected by a trained observer from real-time images of Papanicolaou-fixed and -stained cytospin smears prepared from pleural, peritoneal, or pericardial effusions. The lymphoid cells were classified by the instrument, based on the size and shape of their nuclear profiles. The morphometric data collected by the instrument were interpreted by a simple rule-based expert system that classified the smears as benign or malignant. One hundred four cases, including 28 malignant lymphomas, 63 benign lymphocytoses, 8 chronic lymphocytic leukemias, and 5 cases with incomplete immunopathologic data, were studied retrospectively. Sixty-three of these effusions had been stained to detect light chain monoclonality. Ninety-one effusions were correctly classified by the expert system. There were four potential false negative diagnoses and one potential false positive diagnosis by the CIM system. Eight effusions from patients with chronic lymphocytic leukemia (CLL) were consistently classified as benign. Although the author's series of patients with a history of CLL is small, their results suggest that CIM is unsuitable for the diagnosis of malignancy in these effusions. If only those effusions from patients with a history of CLL are excluded, the predictive value of a diagnosis of malignant lymphoma was 96.5%, whereas the predictive value of a diagnosis of benign lymphocytosis was 94.0%.
Algorithms↗
Cytodiagnosis of malignant melanoma. Immunoperoxidase staining with HMB-45 antibody as an aid to diagnosis.
The specificity and sensitivity of HMB-45, an antimelanoma monoclonal antibody, was evaluated in cytologic specimens from extracutaneous melanomas. Melanoma cells in 23 of 25 (92%) cases stained with this antibody. Staining was intense and diffuse in 22 of these melanomas and focal in 1. Amelanotic tumors and tumors with scanty pigment were included. Neither degree of pigmentation, site of primary, cytologic characteristics of tumor, nor source of specimen predicted the immunostaining pattern. Cytopreparations containing benign (6 cases) and malignant (16 cases) cells with which melanoma may be confused constituted the nonmelanoma group. None of the 22 cases in this group stained. Undifferentiated carcinomas, adenocarcinomas, large cell lymphomas, sarcomas, mesothelial hyperplasias, and a benign nerve sheath tumor were included. Effusions, fine-needle aspirates, bronchial material, and imprints were studied. All smears had been fixed and stained by Papanicolaou's method before immunostaining. Excellent cytomorphologic characteristics were preserved, and immunostaining was not affected. HMB-45 antibody is a highly specific and sensitive marker for malignant melanoma in cytologic material.
Antibodies, Monoclonal↗
Chorismate aminations: partial purification of Escherichia coli PABA synthase and mechanistic comparison with anthranilate synthase.
Chorismate is converted by regiospecific amination/aromatization sequences to o-aminobenzoate and p-aminobenzoate (PABA) by anthranilate synthase (AS) and PABA synthase (PABS), respectively. We report here the first partial purification of the large subunit of Escherichia coli PABA synthase, previously reported to be quantitatively inactivated in purification attempts. The subunit encoded by the pabB gene was overexpressed from a T7 promoter and purified 9-fold to 25-30% homogeneity. The pabB subunit appears unusually sensitive to inactivation by glycerol so this cosolvent is contraindicated. The Km for chorismate is 42 microM in the ammonia-dependent conversion to PABA, and we estimate a turnover number of 2.6 min-1. A variety of chorismate analogues have been prepared and examined. Of these compounds, cycloheptadienyl analogue 11 has been found to be the most potent inhibitor of Serratia marcescens anthranilate synthase (Ki = 30 microM for an RS mixture) and of the E. coli pabB subunit of PABA synthase (Ki = 226 microM). Modifications in the substituents at C-3 [enolpyruyl ether, (R)- or (S)-lactyl ether, glycolyl ether] or C-4 (O-methyl) of chorismate lead to alternate substrates. The Vmax values for (R)- and (S)-lactyl ethers are down 10-20-fold for each enzyme, and V/K analyses show the (S)-lactyl chorismate analogue to be preferred by 12/1 over (R)-lactyl for anthranilate synthase while a 3/1 preference was observed for (R)-/(S)-lactyl analogues by PABA synthase. The glycolyl ether analogue of chorismate shows 15% Vmax vs. chorismate for anthranilate synthase but is actually a faster substrate (140%) than chorismate with PABA synthase, suggesting the elimination/aromatization step from an aminocyclohexadienyl species may be rate limiting with AS but not with PABS. Indeed, studies with (R)-lactyl analogue 14 and anthranilate synthase led to accumulation of an intermediate, isolable by high-performance liquid chromatography and characterized by NMR and UV-visible spectroscopy as 6-amino-5-[(1-carboxyethyl)oxy]-1,3-cyclohexadiene-1-carboxylic acid (17). This is the anticipated intermediate predicted by our previous work with conversion of synthetic trans-6-amino-5-[(1-carboxyethenyl)oxy]-1,3-cyclohexadiene-1-carbo xylic acid (2) to anthranilate by the enzyme. Compound 17 is quantitatively converted to anthranilate on reincubation with enzyme, but at a 1.3-10-fold lower Vmax than starting lactyl substrate 14 under the conditions investigated; the basis for this kinetic variation is not yet determined.
Anthranilate Synthase↗
Epithelial membrane antigen in the cytodiagnosis of effusions and aspirates: immunocytochemical and ultrastructural localization in benign and malignant cells.
Immunoreactivity for epithelial membrane antigen (EMA) was evaluated in exfoliated benign and malignant cells using immunoperoxidase and immunogold techniques. In addition, protein A-colloidal gold was used for ultrastructural localization of EMA. Our results suggest that EMA is useful in distinguishing adenocarcinoma cells (strongly positive) from reactive mesothelial cells (negative or weakly positive), lymphoid cells (negative), and a variety of nonepithelial neoplasms (negative) with which they may be confused. Exfoliated cells from two mesotheliomas were also strongly positive for EMA. Ultrastructurally, EMA was distributed in a dense, even, linear pattern along the cell membrane and microvillous surface processes of adenocarcinoma cells. A similar but sparse distribution pattern was observed in reactive mesothelial cells. These observations reflect the increased sensitivity and higher resolution of the immunogold technique.
Adenocarcinoma↗
Thrombosed, ruptured atheromatous plaques in saphenous vein coronary artery bypass grafts: ten years' experience.
During the past decade the number of patients undergoing saphenous vein coronary artery bypass grafting (CABG) has increased worldwide. With a rate of late graft occlusion approximating 4% each year, the number of patients at risk for late graft occlusion continues to increase. Whereas in 1976 only 0.8% of the CABGs performed at our institution were reoperations for occluded grafts, by 1985 repeat procedures comprised 12.4% of the CABGs performed. Excised, occluded saphenous vein grafts from 52 of 119 (44%) of these patients showed thrombosis superimposed on ruptured atheromatous plaques. Ten autopsy patients showed similar lesions in their occluded grafts. The lesion was present in grafts excised as early as 3 years and as late as 14 years after bypass surgery; most occurred 5 to 10 years after implantation. Neither age at first bypass, sex, nor coronary artery bypassed permitted prediction of the occurrence of the lesion. Thrombosed, ruptured atheromatous plaque is a common, clinically significant mechanism of late graft occlusion. It is associated with recurrent symptoms that necessitate repeat revascularization and may result in death. The lesion may also be amenable to thrombolytic therapy, angioplasty, or both.
Acute Disease↗
Bacterial organomercurial lyase: overproduction, isolation, and characterization.
Organomercurial lyase mediates the first of two steps in the microbial detoxification of organomercurial salts. This enzyme encoded on the plasmid R831 obtained from Escherichia coli J53-1 has been overproduced to the level of 3% of the soluble cell protein in E. coli by a construction using the T7 promoter. The enzyme has been purified to homogeneity in quantity in three steps. It is a monomer of Mr 22,400 with no detectable cofactors or metal ions. It catalyzes the protonolysis of the C-Hg bond in a wide range of organomercurial salts (primary, secondary, tertiary, alkyl, vinyl, allyl, and aryl) to the hydrocarbon and mercuric ion with turnover rates in the range of 1-240 min-1.
Amino Acid Sequence↗