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D E Burstein

Publications and source records attributed to D E Burstein.

31 records · Page 2Linked to original sources

Lithium ion inhibits nerve growth factor-induced neurite outgrowth and phosphorylation of nerve growth factor-modulated microtubule-associated proteins.

LiCl (2.5-20 mM) reversibly suppressed nerve growth factor (NGF)-induced neurite outgrowth by cultured rat PC 12 pheochromocytoma cells. Similar concentrations of LiCl also reversibly blocked NGF-dependent regeneration of neurites by PC12 cells that had been primed by long-term pre-exposure to NGF and by cultured newborn mouse sympathetic neurons. In contrast, transcription-dependent responses of PC12 cells to NGF such as priming and induction of the NGF-inducible large external glycoprotein, occurred despite the presence of Li+. SDS PAGE analysis of total cellular phosphoproteins (labeled by 2-h exposure to 32P-orthophosphate) from neurite-bearing primed PC12 cells revealed that Li+ reversibly inhibited the phosphorylation of a band of Mr 64,000 that was barely detectable in NGF-untreated PC12 cells. However, Li+ did not appear to affect the labeling of other phosphoproteins in either NGF-primed or untreated PC12 cultures, nor did it affect the rapid increase in phosphorylation of several proteins that occurs when NGF is first added to unprimed cultures. Several criteria indicated that the NGF-inducible phosphoprotein of Mr 64,000 is a microtubule-associated protein (MAP). Of the NGF-inducible phosphorylated MAPs that have been detected in PC12 cells (Mr 64,000, 72,000, 80,000, and 320,000), several (Mr 64,000, 72,000, and 80,000) were found to be substantially less phosphorylated in the presence of Li+. Neither a phorbol ester tumor promotor nor permeant cAMP analogs reversed the inhibitory effects of Li+ on neurite outgrowth or on phosphorylation of the component of Mr 64,000. Microtubules are a major and required constituent of neurites, and MAPs may regulate the assembly and stability of neuritic microtubules. The observation that Li+ selectively inhibits NGF-induced neurite outgrowth and MAP phosphorylation suggests a possible causal relationship between these two events.

Animals↗

Evidence for RNA synthesis-dependent and -independent pathways in stimulation of neurite outgrowth by nerve growth factor.

Studies on the mechanism of action of nerve growth factor (NGF) were carried out with PC12 rat pheochromocytoma cells. PC12 cells are uniquely useful for such studies because they respond to, but (unlike normal neurons) do not require, NGF and may undergo either generation or regeneration of neurites in response to NGF. Regeneration is defined here as NGF-dependent regrowth of neurites within 24 hr after subculture of NGF-treated PC12 cells. As in cultures of normal NGF-responsive neurons, neurite regeneration by PC12 cells occurs even in the presence of high concentrations of RNA synthesis inhibitors. Generation of neurites is defined as the de novo initiation of outgrowth when PC12 cells are exposed to NGF for the first time. In contrast to regeneration, neurite generation takes place with a lag of at least 24 hr and is blocked by low concentrations of RNA synthesis inhibitors. Such findings suggest that there are both RNA synthesis-dependent and -independent pathways in the mechanism whereby NGF stimulates neurite outgrowth. In addition, NGF-treated PC12 cells undergo a time-dependent loss of the capacity for neurite regeneration after pretreatment with RNA synthesis inhibitors or withdrawal of NGF. Such findings suggest that (i) initiation of neurite outgrowth requires NGF-stimulated, RNA synthesis-dependent accumulation of intracellular material(s), (ii) once such accumulation occurs, RNA synthesis-independent regeneration can occur (but only in the presence of NGF), and (iii) the turnover of such material(s) in the absence of their replacement leads to loss of the capacity for regeneration. A tentative sequence is presented for the events whereby NGF may stimulate neurite outgrowth.

Camptothecin↗

Cytologic findings in the differential diagnosis of C-cell hyperplasia and medullary carcinoma by fine needle aspiration. A case report.

BACKGROUND: The cytologic features of C-cell hyperplasia of the thyroid have not been previously addressed in the literature. We describe the first case, to our knowledge, of C-cell hyperplasia that was suggested by fine needle aspiration. CASE: Cellular material was obtained from a nonnodular region of the thyroid gland in a 67-year-old male with chronic diarrhea, unexplained elevated serum calcitonin, no clinically detectable thyroid mass and no known medical or family history of an endocrine disorder. Aspiration yielded a scant bimodal cell population composed of benign follicular cells and a second population of larger cells, later confirmed as C-cells via immunohistochemistry. Although the diagnosis of medullary carcinoma was entertained, the absence of a discrete mass clinically and the presence of two interspersed, distinct cell populations suggested the alternate diagnosis, C-cell hyperplasia, which was confirmed by subsequent thyroidectomy. CONCLUSION: C-cell hyperplasia can mimic medullary carcinoma biochemically, and this case suggests the possible role of fine needle aspiration of the thyroid to distinguish between the two. In patients with elevated serum calcitonin and absence of a discrete thyroid nodule, the finding of clusters of calcitonin-positive cells intermixed with normal follicular cells by fine needle aspiration may provide a means of making a presurgical diagnosis of C-cell hyperplasia.

Aged↗

Value of GCDFP-15 (BRST-2) as a specific immunocytochemical marker for breast carcinoma in cytologic specimens.

OBJECTIVE: The diagnosis of metastatic mammary carcinoma by morphologic criteria alone can be difficult, depending on the site of metastasis and state of cell differentiation. Numerous histopathologic studies have shown GCDFP-15 (BRST-2) to be a specific marker for breast cancer in surgical specimens. To date, no studies have been done to evaluate its utility in cytologic preparations. STUDY DESIGN: To evaluate the usefulness of GCDFP-15 as a marker in the cytologic diagnosis of breast carcinoma, we studied 23 cases of mammary carcinoma and compared them with 20 cases of tumors of nonmammary origin (lung, ovary, liver, colon, stomach and bladder). "Bench top" fine needle aspirates from unfixed surgical specimens of breast carcinoma, cytocentrifuge samples from body cavity fluids and cerebrospinal fluids with morphologically proven metastatic carcinoma were studied. RESULTS: Expression of BRST-2 was found in 56.5% of primary and recurrent or metastatic breast carcinomas. All the nonmammary carcinomas studied were negative. Staining was found to be strongly dependent on the means of cell fixation. Slides fixed in 10% formalin and Bouin's solution gave optimal results. Except in two cases, which showed focal immunostaining, all specimens fixed in alcohol were negative. CONCLUSION: Our results support the diagnostic value of GCDFP-15 in recognizing tumors of breast origin and suggest that in clinical situations in which metastatic breast carcinoma is suspected, a portion of the cytologic specimen should be fixed with an optimal fixative for BRST-2 detection.

Antibodies, Monoclonal↗

Cytology of extrapulmonary Pneumocystis carinii infection in the acquired immunodeficiency syndrome.

Rare cases of extrapulmonary Pneumocystis carinii (EPPC) have been seen in patients with acquired immunodeficiency syndrome (AIDS). We report seven such diagnoses of nonpulmonary P carinii (PC) from four AIDS patients between 1986 and 1989. The specimens included fine needle aspirate of liver, spleen, periarticular tissue and pleura as well as ankle fluid, pleural fluid and ascites. In some, but not all, cases the patients had concurrent or previous episodes of PC pneumonia. In all cases the typical granular, eosinophilic aggregates of PC cysts were noted on routine Papanicolaou staining, leading to the definitive detection of PC cysts with Grocott silver stain. In most cases, evidence for granulomalike and neovascularized tissue reaction was present in cytologic material. One specimen demonstrated concurrent acid fast bacilli. In the setting of AIDS, cytology of effusions and masses should include an evaluation for EPPC.

Acquired Immunodeficiency Syndrome↗

Immunocytochemical detection of cyclin, a proliferation-associated protein, in cytologic preparations.

Cyclin is a nuclear protein associated with DNA-polymerase delta, whose expression correlates with cell proliferation in vitro. To assess the value of cyclin staining in diagnostic cytology, an anticyclin monoclonal antibody was used to survey cyclin expression in cytologic preparations obtained as "bench top" aspirates from surgically resected specimens. The tissues assayed included carcinomas and normal and benign proliferative tissues of renal, mammary, prostatic and colonic origin. Staining was performed via the avidin-biotin-complex immunoperoxidase method. The staining of tumor cells was nuclear, with sparing of the nucleoli; the results were variable in different areas of a given tumor and varied significantly between tumors of the same histopathologic type. Benign proliferative tissues also showed staining. Nonproliferative tissues, such as renal tubules adjacent to a renal cell adenocarcinoma, were largely, but not entirely, nonstaining. The percentage of cyclin-positive nuclei was sometimes much higher than the typical percentages of tumor cells found in S phase. This observation was confirmed in two cases in which cyclin staining was much greater than the percentage of S-phase cells detected by flow cytometry. This suggests either stabilization of the protein beyond S phase in cells and/or dysregulation of cyclin expression in malignant cells. The viability of unfixed surgically resected tissue may also have affected the detection of cyclin, a problem that should not exist with clinically aspirated tissue fixed immediately after aspiration. These preliminary observations suggest that the selective use of cyclin staining may facilitate cytologic diagnoses. Furthermore, the wide range of cyclin expression within tumors of one histologic type suggests that cyclin expression may serve as a new parameter for investigating tumor behavior and prognosis.

Antibodies, Monoclonal↗

Fine needle aspiration biopsy diagnosis of tuberculous lymphadenitis in patients with and without the acquired immune deficiency syndrome.

All Bellevue Hospital cases from a recent 27-month period whose fine needle aspiration (FNA) samples of cervical or supraclavicular masses showed acute and/or granulomatous inflammation were reviewed. The 30 patients included 8 with the acquired immune deficiency syndrome (AIDS), 3 with the AIDS-related complex (ARC), 2 with AIDS risk factors and 17 without known risk factors for AIDS. Of these, mycobacterial infections had been diagnosed in 22 patients: 18 by cultures positive for Mycobacterium tuberculosis and 4 by positive staining for acid-fast bacilli. In addition to the presence of neutrophils, two criteria for the diagnosis of mycobacterial infection were identified on the routinely stained FNA smears: caseous material and granulomas. Caseous material was the most sensitive and specific criterion. Granulomas were often present in patients with mycobacterial infection, but were also occasionally present in patients with other processes. The differences in cytologic specimens between AIDS and non-AIDS patients are discussed. The findings suggest that FNA is a safe and sensitive technique for the diagnosis of mycobacterial lymphadenitis in AIDS patients and that purulent aspirates from appropriate patient populations should prompt the use of special stains and cultures to rule out mycobacterial infection.

AIDS-Related Complex↗

Fine needle aspiration biopsy of cystic benign lymphoepithelial lesion of the parotid gland in patients at risk for the acquired immune deficiency syndrome.

Cystic benign lymphoepithelial lesion (BLL), a previously rare lesion of the parotid gland consisting of marked lymphoid hyperplasia with accompanying squamous-lined cysts, has recently been described in patients with the acquired immune deficiency syndrome (AIDS) or AIDS risk factors. Thirteen fine needle aspiration (FNA) samples of parotid gland masses from patients with AIDS (one case), AIDS risk factors (five cases) or denial of AIDS risk factors (two cases) and a histopathologic diagnosis of BLL were examined. The FNA features that correlated best with the histopathologic findings were (1) a heterogeneous lymphoid population, (2) scattered single and/or clustered foamy macrophages and (3) superficial and/or anucleated squamous cells. Most aspirates showed some combination of these three components. The differential diagnostic considerations, the clinical and radiologic correlations and the relationship of this lesion to HIV infection are discussed. Patients with parotid masses whose aspirates consist of some combination of squamous cells, lymphocytes and foamy macrophages should be questioned for possible AIDS risk factors.

Acquired Immunodeficiency Syndrome↗

Cytologic findings in progressive multifocal leukoencephalopathy. Report of two cases.

Cytologic preparations from two cases of progressive multifocal leukoencephalopathy (PML) were obtained by stereotactically guided needle biopsies using computerized tomograms of the brain. Case 1 was a 32-year-old man with an acquired immunodeficiency syndrome-related complex. Case 2 was a 71-year-old man with chronic lymphocytic leukemia. Smears showed moderate cellularity, consisting of moderately to markedly atypical cells with enlarged hyperchromatic nuclei. The chromatin pattern showed smudging, with or without clumping, similar in pattern to the human polyomavirus-infected "decoy" cells seen in urine cytology. Nuclei were predominantly round to oval, smoothly contoured and often stripped of cytoplasm. Occasional bizarre lobulated or multinucleated forms were seen. Some atypical cells had abundant cytoplasm exhibiting stellate projections. Histologic sections of the biopsy material confirmed the diagnosis in each case. In both cases, electron microscopy demonstrated intranuclear polyoma-type virus particles. The present findings suggest that PML should be considered in the differential diagnosis of marked cytologic atypia in brain aspirates from immunocompromised patients.

AIDS-Related Complex↗