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D J Dabbs

Publications and source records attributed to D J Dabbs.

At least 37 records · Page 2Linked to original sources
PubMed1994

Bilirubin, ferritin, D-dimers and erythrophages in the cerebrospinal fluid of patients with suspected subarachnoid haemorrhage but negative computed tomography scans.

AIM: To assess the diagnostic value of cerebrospinal fluid (CSF) spectrophotometry, cytology, ferritin, and D-dimer measurements in the investigation of suspected subarachnoid haemorrhage in patients with negative or equivocal computed tomography (CT) scans. METHODS: CSF specimens submitted for assessment of xanthochromia were examined for erythrophages using a cytospin preparation stained with Wright's stain, for ferritin using the Ciba-Corning Magic IRMA assay, D-dimers using the Dimertest 2 latex agglutination slide test, and for bilirubin by scanning spectrophotometry. The patients were divided into three groups for data analysis and the results compared with the existing methods, CT, and angiogram results. Final diagnoses were reviewed by a consultant neurologist. RESULTS: Thirty six patients were recruited. In those patients with confirmed subarachnoid haemorrhage CSF cytology had a low sensitivity and there were false negative results with both the D-dimer and ferritin assays. Eleven patients with a negative or equivocal CT scan underwent angiography, but only one aneurysm and no arterio-venous malformations or bleeding points were identified. In the patient with the aneurysm there was no laboratory evidence of subarachnoid haemorrhage. Six patients had CSF abnormalities detected by the special tests only and in none of these cases was subarachnoid haemorrhage confirmed. All results were normal in four out of five cases of traumatic tap. CONCLUSIONS: This is a small study, but it shows that, depending on the timing of the lumbar puncture, false negative results can occur with both ferritin and D-dimer measurements. It suggests that neither of these tests adds significantly to the information provided by CT, visualisation of CSF, and spectrophotometry and confirms that, despite the use of spectrophotometry, D-dimer and ferritin assays in selecting patients for angiography, the proportion of patients with negative CT scans and colourless CSF with demonstrable vascular lesions remains low.

Bilirubin↗
PubMed1994

Angiomyolipomas: the nature and expression of the HMB45 antigen.

Fifteen cases of angiomyolipoma (AML) were studied by the immunoperoxidase method to investigate the nature of the HMB45 antigen and to determine if the antigen that stains with HMB45 in AML is the same HMB45 antigen that stains melanoma cells. Other antibodies utilized to accomplish this study included vimentin, cytokeratin, S-100 protein, and muscle actin (HHF-35). Large interstitial cells of AML regularly react with two different sources of HMB45 and are often positive for vimentin. The HMB45 reactivity of both antibodies is abolished by pretreating the tissue with neuraminidase. The same cells are not immunoreactive with cytokeratin or S-100 protein. A subpopulation of cells in AML demonstrates coexpression of HMB45 and muscle-specific antigen by double-immunolabeling techniques. These results suggest that the AML antigen that reacts with HMB45 is the same antigen present in melanocytic/melanoma cells and that a pluripotent cell, which generates a divergent range of differentiation, may be involved in the genesis of AMLs.

Angiomyolipoma↗
PubMed1993

Mammary ductal foam cells: macrophage immunophenotype.

Mammary ductal foam cells are present in normal breast tissue as well as in a number of breast diseases. Such foam cells tend to be in particular abundance with fibrocystic changes of the breast. Foam cells may appear within duct lumens or plastered in cohesive masses along duct walls, simulating an epithelial structure. The nature and origin of these innocuous-appearing cells, based on morphologic studies, remain a controversy, for they appear to be of epithelial derivation. This study was undertaken to determine the nature of intraductal "foam" cells and their origin in the breast. Nine cases of adult fibrocystic disease were examined immunohistochemically with antibodies to cytokeratins (Mak-6, Cam 5.2), leukocyte common antigen, and the following macrophage antibodies: KP-1 (CD68), HAM 56, and MAC 387. The lysozyme and alpha-1-antitrypsin content of foam cells also was studied. The immunohistochemical data in this study confirm the macrophage character of these foam cells, which are positive for CD68, HAM 56, and MAC 387, lysozyme, and alpha-1-antitrypsin and negative for leukocyte-common antigen and cytokeratins.

Antibodies↗
PubMed1993

Ductal carcinoma of breast: nuclear grade as a predictor of S-phase fraction.

Nuclear grade (NG) and S-phase fraction (SPF) are established independent prognostic variables for ductal breast carcinomas. Nuclear grade can be assigned by a pathologist in a simple fashion during histopathologic evaluation of the tumor, while SPF requires flow cytometric evaluation of tumor samples. This prospective study was undertaken to determine whether elevated SPF could be predicted from NG alone and how NG and SPF correlate with c-erbB-2 expression. Eighty-two breast carcinomas of ductal type were assigned an NG of low (grade 1 or grade 2) or high (grade 3). S-phase fraction was recorded initially from fresh-frozen tissue samples and was designated as either low SPF (below the value designated as the cutoff for elevated SPF) or high SPF (a value at or greater than the cutoff value). On fresh tissue the NG predicted the range of SPF (low or high) in 89% of cases. Four percent of the cases that did not correlate could definitely be attributed to sample error. The remaining 7% that did not correlate could have been due to sample error, specimen quality, or tumor heterogeneity, as demonstrated by reversal of SPF range as performed on paraffin blocks of tumor. Eighty-eight percent of the tumors positive for c-erbB-2 were NG 3 and 12% were NG 2. All c-erbB-2 tumors were aneuploid. This study demonstrates the importance of carefully assigning NGs on tissue and indicates the importance of reviewing flow cytometric data side by side with histopathologic parameters to detect discrepancies between these two modalities. Careful nuclear grading assignment can accurately predict the range of SPF.

Breast Neoplasms↗
PubMed1993

Eosinophilic and lymphoeosinophilic cholecystitis.

Eosinophilic cholecystitis (EC) is an infrequent and poorly understood inflammatory condition of the gallbladder. First described in 1949, EC may be defined as an inflammatory condition of the gallbladder in which the inflammatory infiltrate is composed predominately of eosinophils so that their presence clearly overshadows the presence of any other inflammatory cell component. In the few reports that describe EC, it has been described in association with acalculous cholecystitis, with subacute cholecystitis lasting 2 to 3 weeks and with several forms of drug therapy. This retrospective clinicopathologic study reviewed the histopathologic features of 217 consecutive cholecystectomy specimens with special clinical reference to the timing of gallbladder removal after symptoms, previous drug therapy, systemic infection, and the presence of cholelithiasis. Pathologically, 48 of these cases (22.2%) contained eosinophils to some degree. Eosinophilic cholecystitis was diagnosed in 14 (6.4%) of the specimens, and another 14 (6.4%) specimens demonstrated substantial numbers of eosinophils but also had other types of inflammatory cells in abundance, including neutrophils and lymphocytes. Of the eight patients with acalculous cholecystitis, six had substantial eosinophils in their gallbladders, whereas the other two patients had no eosinophils. In this study, EC was more prevalent than in other reported series, and it did not show any association with the timing of gallbladder removal after initial symptoms, drug therapy, or other preexisting medical conditions. Eosinophilic cholecystitis is more common than previously recognized and probably represents a subgroup of patients with a unique or hypersensitivity type of inflammatory response to altered bile. Large numbers of eosinophils in the inflammatory infiltrate occurred three times more commonly in patients with acalculous cholecystitis than in patients with cholelithiasis.

Adult↗
PubMed1990

Fine-needle aspiration cytology of malignant hemangiopericytomas with ultrastructural and flow cytometric analyses.

A hemangiopericytoma (HPC) is an uncommon soft-tissue neoplasm that may arise in many body sites. The cytologic features of fine-needle aspirates (FNAs) of HPCs have only rarely been described in the literature. We examined FNAs of malignant HPCs from the head and neck region (three) and the retroperitoneum (one) in four adults (aged 38 to 83 years). All four FNAs yielded cellular specimens that consisted of uninuclear tumor cells with high nuclear-cytoplasmic ratios. The cytomorphological spectrum included nuclei that were oval to elongate and had very finely granular, evenly distributed chromatin with one or two small but distinct nucleoli. Hemangiopericytomas yield aspirates that may be considered malignant and may suggest sarcoma. Histologically, all four neoplasms manifested high mitotic activity. The ultrastructural features of all four tumors were supportive of the diagnosis of HPC. Although a specific primary diagnosis of HPC on FNA of a soft-tissue mass is unlikely, cytologic analysis may allow diagnosis of recurrent or metastatic HPC. We were able to perform flow cytometric determinations of tumor DNA content on three of the resected neoplasms. In two, an aneuploid pattern was found, including the neoplasm with the most marked pleomorphism in the FNA. The third was diploid.

Adult↗
PubMed1989

Immunohistochemical study of uterine stromal sarcoma and rhabdomyosarcoma.

The cytoplasmic filament composition of two pure high-grade endometrial stromal sarcomas and five pure endometrial rhabdomyosarcomas was studied using the immunoperoxidase avidin-biotin method. Ultrastructural correlates were performed on the same tissues. While four of the seven tumors presented as high-grade undifferentiated neoplasms, they were readily categorized on the basis of immunocytochemical findings in which the five rhabdomyosarcomas were positive for muscle-specific actin (HHF 35) and the two stromal sarcomas were positive for vimentin only. Ultrastructure on the HHF 35-positive cases showed the presence of thick filaments and Z-band material, whereas the other tumors showed no cytoplasmic differentiation. Muscle-type actin differs stromal cells, and is useful when used in conjunction with a panel of antibodies in the categorization of undifferentiated endometrial sarcomas.

Biomarkers, Tumor↗
PubMed1989

The impact of fine-needle aspiration biopsy on a diagnostic electron microscopy laboratory.

We retrospectively reviewed the number and types of diagnostic electron microscopic specimens from a 4 1/2-year period. During this period, the number of fine-needle aspirate biopsy specimens processed increased in a linear fashion, from a relatively uncommon occurrence to the current level of activity, in which fine-needle aspiration specimens now represent 40% to 50% of the nonrenal diagnostic material examined by electron microscopy. This study documents the increasing importance of fine-needle aspirate-type specimens in the everyday operation of a diagnostic electron microscopy facility.

Biopsy, Needle↗
PubMed1988

Common epithelial ovarian tumors. Immunohistochemical intermediate filament profiles.

The authors studied 79 common epithelial ovarian tumors in order to ascertain the intermediate filament profiles in formalin-fixed and methacarn-fixed, paraffin-embedded surgical pathology materials. Ultra-structural correlations were attempted with several tumors. All categories of common benign and malignant epithelial tumors were examined. Antibodies used in the study included antikeratins (AE1/AE3, 35BH11, 34BE12), carcinoembryonic antigen (CEA), and vimentin. All ovarian epithelial tumors expressed keratin in uniform fashion, except high molecular weight keratin (34BE12) which was focal. Vimentin was coexpressed with cytokeratins in 42% of serous carcinomas, 71% of endometrioid carcinomas, and 7% of clear cell carcinomas. Vimentin decoration in serous carcinoma was very focal, whereas endometrioid decoration tended to involve larger areas, similar to uterine-based endometrial adenocarcinoma. Mucinous, Brenner, and solid (not otherwise specified) ovarian tumors were positive only for cytokeratin. Carcinoembryonic antigen luminal staining was present in 52% of serous carcinomas and 87% of mucinous carcinomas. Whereas there are distinct differences in intermediate filament expression among ovarian carcinomas, these differences do not allow for specific categorization of ovarian neoplasms because there is some overlap of intermediate filament expression. In order to differentiate ovarian carcinoma from other carcinomas and mesothelioma, other methods of study would be necessary in addition to intermediate filament profiles, such as CEA immunohistochemistry, mucin histochemistry, and ultrastructural study.

Carcinoembryonic Antigen↗
PubMed1988

Fine-needle aspiration cytology of pulmonary carcinosarcoma with immunocytochemical and ultrastructural observations.

The cytologic, immunocytochemical, and ultrastructural features of a pulmonary carcinosarcoma diagnosed by fine-needle aspiration biopsy are presented. Both malignant epithelial groups and bizarre spindle-shaped cells arranged in loose groups, microtissue fragments and in a dissociate fashion showed dual immunoperoxidase staining with cytokeratins and vimentin. Although the immunocytochemical staining pattern is typical of this neoplasm, it does not allow differentiation in all cases from the more common primary large-cell undifferentiated carcinoma, which can also show dual staining for cytokeratin and vimentin. However, the presence of poorly differentiated epithelial groupings associated with a malignant mesenchymal component set in a myxoid stroma should suggest the correct diagnosis. Cytologically, differentiating carcinosarcoma, a poorly differentiated malignancy showing dual staining for cytokeratin and vimentin, from a large-cell carcinoma is important, since the former may pursue a more indolent clinical course.

Biopsy, Needle↗
PubMed1988

Clinical utility of fine needle aspiration in the diagnosis and management of neuroblastoma.

Eleven fine needle aspiration (FNA) biopsies were performed in five children with neuroblastoma, including one patient with peripheral neuroectodermal tumor of the thoracopulmonary region (Askin tumor). Cytologic features in conjunction with immunocytochemistry and electron microscopy on the aspirated material enabled us to make a primary diagnosis in four of the five patients and diagnose local recurrence and metastatic disease in three patients. There were no false-positive or false-negative cytologic diagnoses; therefore, diagnostic accuracy was 100%. FNA is an extremely useful technique for the primary diagnosis and management of neuroblastoma and excludes other small cell malignancies of children. The results of this study and literature review demonstrate that FNA cytology coupled with ancillary techniques of immunocytochemistry and electron microscopy is a rapid, safe, minimally invasive procedure which can aid in the diagnosis and management of patients with neuroblastoma without resorting to more aggressive diagnostic procedures in selective cases.

Biopsy, Needle↗
PubMed1988

Renal vascular smooth muscle proliferation in neurofibromatosis.

An unusual vascular lesion was seen in a 14-year-old white boy with renal vascular hypertension and neurofibromatosis. Microscopically, nodular intimal and medial proliferations of spindle-shaped cells involved arteries, arterioles, and veins of all caliber within the renal parenchyma. Immunoperoxidase studies indicated these cells to have characteristics of smooth muscle, and this finding was confirmed by ultrastructural examination. Despite the generalized nature of the process in the biopsy sample, the patient's hypertension responded well to surgical treatment.

Adolescent↗
PubMed1988

Fine-needle aspiration biopsy of pleomorphic (giant cell) carcinoma of the pancreas. Cytologic, immunocytochemical, and ultrastructural findings.

Four cases of pleomorphic (giant cell) carcinoma (PGC) of the pancreas, diagnosed by fine-needle aspiration biopsy, are presented. Ancillary immunocytochemical studies were also performed on the smears (four cases) and cell blocks (three cases), along with ultrastructural (electron microscopic) examination of the aspirated specimen (two cases). Three of the four patients were elderly (age range: 44-65 years), and all had large pancreatic masses. A spectrum of cytomorphologic features was encountered, including poorly cohesive bizarre mononuclear cells, many multinucleated tumor giant cells, and associated malignant spindle cells. Prominent cellular cannibalism and cytophagocytosis also were seen. Immunoperoxidase studies demonstrated dual staining of the malignant cells for cytokeratin and vimentin in two cases and exclusive staining for vimentin in the remaining two cases. Ultrastructural examination demonstrated epithelial features in both cases studied. One of the cases demonstrated intracytoplasmic whorled bundles of intermediate filaments, corresponding to pale eosinophilic globular material, appreciated both in the Diff-Quik- and Papanicolaou-stained smears and staining with positive results for vimentin. The immunocytochemical studies suggest that the coexpression of vimentin and cytokeratin within the cells is consistent with a pleomorphic malignancy of epithelial origin. It is speculated that the staining of two of the cases exclusively for vimentin can be seen in either epithelial malignancies with sarcomatoid transformation or, less likely, a pure sarcoma of the pancreas.

Adult↗
PubMed1988

Malignant rhabdoid skin tumor: an uncommon primary skin neoplasm. Ultrastructural and immunohistochemical analysis.

Rhabdomyosarcomatoid renal tumors were initially described as a subset of tumors in the National Wilms Tumor Study that had light microscopic features similar to rhabdomyosarcomas. Subsequent studies failed to reveal evidence of muscle differentiation, thus the genesis of the term "rhabdoid" tumor. Such renal tumors are rapidly lethal. Recent reports suggest the occurrence of tumors with similar morphology in other anatomic sites. We wish to report a primary malignant rhabdoid tumor of the facial skin with detailed immunohistochemical and ultrastructural studies. Vimentin was expressed in the tumor cells, but there was no immunoreactivity for cytokeratins, neurofilaments, muscle actin, synaptophysin, S-100, melanoma antigen HMB-45, epithelial membrane antigen, neuron specific enolase, Leu-7, leucocyte common antigen or lysozyme/alpha-1-antitrypsin. Ultrastructure revealed typical whorled cytoplasmic aggregates of intermediate filaments. These studies along with a literature review reveal the heterogeneous immunohistochemical profiles of these tumors with common morphologic features. While the histogenesis of these tumors remain uncertain, it is necessary to recognize that these aggressive neoplasms may occur primarily in the skin.

Forehead↗
PubMed1988

An in vitro human muscle preparation suitable for metabolic studies. Decreased insulin stimulation of glucose transport in muscle from morbidly obese and diabetic subjects.

We have developed an in vitro muscle preparation suitable for metabolic studies with human muscle tissue and have investigated the effects of obesity and non-insulin-dependent diabetes mellitus (NIDDM) on glucose transport. Transport of 3-O-methylglucose and 2-deoxyglucose was stimulated approximately twofold by insulin in muscle from normal nonobese subjects and stimulation occurred in the normal physiological range of insulin concentrations. In contrast to insulin stimulation of 3-O-methylglucose and 2-deoxyglucose transport in muscle from normal, nonobese subjects, tissue from morbidly obese subjects, with or without NIDDM, were not responsive to insulin. Maximal 3-O-methylglucose transport was lower in muscle of obese than nonobese subjects. Morbidly obese patients, with or without NIDDM, have a severe state of insulin resistance in glucose transport. The novel in vitro human skeletal muscle preparation herein described should be useful in investigating the mechanism of this insulin resistance.

3-O-Methylglucose↗