Irregular Nuclear Shape Research Articles

Guide to diagnosing primary pancreatic lymphoma, B‐cell type: Immunocytochemistry improves the diagnostic accuracy of endoscopic ultrasonography‐guided fine needle aspiration cytology

Primary pancreatic lymphoma (PPL) is a rare disease with <1%of extranodal non-Hodgkin's lymphoma arising in the pancreas. This report provides immunocytochemical information on PPL that would be valuable for making differential diagnoses between PPL, pancreatic neuroendocine tumor, acinar cell carcinoma, and pancreatic ductal cancer. A 68-year-old woman had a chief complaint of abdominal pain. Fine needle aspiration cytology (FNAC)was performed. The FNAC smear showed moderate cellularity,with a small to moderate number of irregular cells and lymphocytes.No epithelial tumor clusters or abundant mucoid background were seen. The cells were scattered with pleomorphism and showed irregular nuclear shapes with finely granular chromatin,an increased nuclei–cytoplasm ratio, and prominent nucleoli.Cytologically, PPL was suspected with Papanicolaou staining but definite diagnosis was not made. Therefore, the specimen was destained, immunocytochemically examined for leukocyte common antigen (LCA), and PPL was suspected again. Numerous tumor cells were found in the surgical sample and tumor cells were positive for CD20 and negative for CD45RO. Based on these findings,the tumor was diagnosed as PPL, B-cell type. The preoperative FNAC smear that was examined for LCA was then reexamined for CD20, CEA, and Synaptophysin. As a result, the tumor cells were positive for LCA and CD20, whereas they were negative for CEA and Synaptophysin. Taking these findings together with the cytopathologic findings, this specimen was reconfirmed as PPL. Immunocytochemical examination for LCA and CD20 is useful in the identification of malignant pancreatic lymphoma, B-cell type.

Effects of Static Compression With Different Loading Magnitudes and Durations on the Intervertebral Disc

An in vivo rat-tail model was used to study the effects of static compression with different loading magnitudes and durations on the intervertebral disc. To investigate the effects of static compression with different loading magnitudes and durations on the intervertebral disc over a period of time. A disc degeneration model is essential for studying therapeutic effects on degenerated disc. Static compression can induce degenerative-like changes in the intervertebral disc. However, the consequences of the simulation model over a period of resting have not been clearly documented, which may have confounding effects on the experimental outcome. Thirty-five rats were used. Static compressions with different loads (11 or 17 N) and durations (1 hour daily or continuous) were applied to the rat-tail caudal 8-9 disc for 2 weeks, and followed with 3 weeks of rest. The disc height was quantified in vivo on days 4, 18, and 39. The rats were killed and the discs were harvested for morphologic examination on day 39 after the disc height measurement. Significant decrease in disc height was observed after continuous static compression for both 11 and 17 N, and continued during the resting period. The morphologic evaluation of the continuous compressed disc showed a decreased nuclear size, reduced number of nuclear cells, and irregular nuclear shape with inward bulging of disorganized annular collagen lamellas. Daily compression of 1 hour was found to induce a transient increase in disc height, but restored after the 3-week resting period. Favorable morphologic changes, including vacuolated nuclear cells and oval nuclear shape with well-organized annular collagen lamellas, were seen in the rat disc specimens with daily compression of 1 hour. Disc degenerative-like changes without recovery were demonstrated in the rat caudal disc after continuous compression. The changes in disc height and disc morphology were found to be dependent on the duration of load application and may have clinical implication.

Lamins A and C but Not Lamin B1 Regulate Nuclear Mechanics

Mutations in the nuclear envelope proteins lamins A and C cause a broad variety of human diseases, including Emery-Dreifuss muscular dystrophy, dilated cardiomyopathy, and Hutchinson-Gilford progeria syndrome. Cells lacking lamins A and C have reduced nuclear stiffness and increased nuclear fragility, leading to increased cell death under mechanical strain and suggesting a potential mechanism for disease. Here, we investigated the contribution of major lamin subtypes (lamins A, C, and B1) to nuclear mechanics by analyzing nuclear shape, nuclear dynamics over time, nuclear deformations under strain, and cell viability under prolonged mechanical stimulation in cells lacking both lamins A and C, cells lacking only lamin A (i.e. "lamin C-only" cells), cells lacking wild-type lamin B1, and wild-type cells. Lamin A/C-deficient cells exhibited increased numbers of misshapen nuclei and had severely reduced nuclear stiffness and decreased cell viability under strain. Lamin C-only cells had slightly abnormal nuclear shape and mildly reduced nuclear stiffness but no decrease in cell viability under strain. Interestingly, lamin B1-deficient cells exhibited normal nuclear mechanics despite having a significantly increased frequency of nuclear blebs. Our study indicates that lamins A and C are important contributors to the mechanical stiffness of nuclei, whereas lamin B1 contributes to nuclear integrity but not stiffness.

Mitotic Polyploidization in Trophoblast Giant Cells of the Alpaca

Genome multiplication is a typical feature of trophoblast giant cell (TGC) development in many species. Elevated nuclear DNA contents can be achieved by modified cell cycles with a complete lack of mitosis (endoreduplication) or with incomplete mitoses. The aim of this study is to characterize genome multiplication in the alpaca TGC. Placental tissues of gestation days 150, 264 and 347 (near term) and term placentae were processed for light microscopy and for transmission electron microscopy. Each TGC showed many nuclear profiles. Observation of serial sections revealed that TGCs are truly multinucleate with several highly lobulated nuclei. Feulgen staining showed that TGC nuclei have a higher DNA content than nuclei of other trophoblast cells. The number of argyrophilic nucleolar organizer regions (AgNORs) in nuclear profiles of TGC was between 15 and 100, while other trophoblast cells showed 1 or 2 AgNORs. Large multipolar mitotic figures with maximal diameters of 80 µm were observed in the alpaca placentas on gestation days 264 and 347. No cytokinesis was seen in TGC. The results show that the mode of genome multiplication in the alpaca TGC is mitotic polyploidization. Subsequent acytokinetic mitoses may lead to an accumulation of chromosomes and centrioles in TGC. With increasing ploidy levels, the shape of these polyploidizing mitoses becomes more irregular. The restitution of nuclei after these complex multipolar mitoses is likely to result in the irregular nuclear shape in TGC.

Irregular nuclear shape of bone marrow plasma cells defines a multiple myeloma subgroup related to hypodiploidy and to short survival

Morphological changes of plasma cells (PC) are common in multiple myeloma (MM). Loss of round or oval nuclear shape has been related to cell malignancy in human, and we looked for the occurrence of such morphological change on PC from bone marrow (BM) smears in a retrospective series of 169 MM patients at diagnosis. Nuclear shape changes of PC differed according to the patients (notch, dumb-bell, folded or monocytoid appearance), even in the same patient; all subtypes were pooled and defined as PC with irregular nuclear shape (PCIN). A significant number of PCIN (≥5% of all BMPC) was found at diagnosis in 20.7%. Median survival was of 22 months for patients with ≥5% PCIN, and 41 months for others ( p = 0.0001). Significant relationship was observed with prognostic parameters related intrinsic malignancy of the tumour process but not with beta-2-microglobulin (b2m). A clear-cut relationship was found also between PCIN and hypodiploidy ( p = 0.0001), but not with deletion of chromosome 13. This study emphasises the relationship between PCIN, an easy-to-ascertain marker of intrinsic malignancy of the tumour process, and adverse prognosis.

Consultation with the Specialist: Childhood Leukemia

1. Jennifer M. Pearce, MD* 2. Richard H. Sills, MD* 1. *Department of Pediatrics, Albany Medical College, Albany, NY Author Disclosure Drs Pearce and Sills did not disclose any financial relationships relevant to this article. After completing this article, readers should be able to: 1. Understand the similarities in presentation of aplastic anemia and childhood leukemia. 2. Know that the absence of blasts in the peripheral blood of a patient who has pancytopenia does not rule out the diagnosis of leukemia. 3. Recognize bone pain as a symptom of leukemia. 4. Delineate the percentage of patients who have standard-risk acute lymphoblastic leukemia and enter remission with initial treatment. 5. Identify the important sites of relapse of acute lymphoblastic leukemia. 6. Identify the relationship of Down syndrome and leukemia. 7. Recognize the potential for a second malignancy following acute lymphoblastic leukemia. A 3-year-old boy develops pallor, bruising, and intermittent fever over 3 weeks. Laboratory findings include: hemoglobin, 6.8 g/dL (68 g/L); white blood cell (WBC) count, 1.8×10 3 /mcL (1.8×10 9 /L) with 2% neutrophils and 98% lymphocytes; platelet count, 25×10 3 /mcL (25×10 9 /L); mature lymphocytes on blood smear; and normal prothrombin and partial thromboplastin times. He is referred to a pediatric hematologist with the concern of aplastic anemia. The bone marrow is hypercellular and replaced with large blasts; immunophenotyping is consistent with acute myeloid leukemia (AML) (Figs. 1and 2). Figure 1. Photomicrograph of bone marrow aspirate smear from Case 1, showing marrow replaced completely with myeloblasts. Identifying features include the very fine nuclear chromatin, large distinct nucleoli, an irregular nuclear shape, and relatively abundant cytoplasm with red granules. Flow cytometry demonstrates that these cells are myeloid in origin because they are positive for the immunophenotypic markers CD13 and CD33. Figure 2. A. Normal section of bone marrow biopsy with the typical heterogenous appearance due to the presence of the different hematopoietic precursors. The clear areas represent the expected amount of fat. B. Biopsy from Case 1, …

Epithelial proliferations of ductal type

The diagnosis of ductal proliferations requires analysis of both architectural and cytological features. Architectural characteristics of conventional ductal hyperplasia include persistence of the duct lumen as peripheral, crescent shaped spaces; streaming of cells; formation of irregular, slit-like fenestrations; and “maturation.” Hyperplastic ductal cells exhibit indistinct cell borders, irregular placement of nuclei, irregular nuclear shapes, granular chromatin, and uniform small nucleoli. The cells do not show polarization or dishesion. Low-grade ductal carcinoma in-situ exhibits both architectural and cytological atypicality. The architectural atypicality takes two forms: the formation of cribriform spaces or their variants and the regular arrangement of cells. The former reflects the polarization of the carcinoma cells and the latter their dishesion. Cytological atypicality includes distinct cell borders; smoothly contoured, oval or round nuclei; homogeneous chromatin; and inconspicuous nucleoli. Atypical ductal hyperplasia shows low-grade cytological atypicality but lacks the architectural atypicality of ductal carcinoma in situ. Proliferations lacking cytological atypicality do not merit the diagnosis of atypical ductal hyperplasia whatever their architectural characteristics. Although not usually necessary, immunohistochemical staining for high molecular weight keratin can help resolve difficult cases. Current evidence does not support the belief that conventional ductal hyperplasia represents an obligate precursor to ductal carcinoma in situ.

Lésions malpighiennes intra-épithéliales de bas grade et de haut grade: Critères cytologiques et corrélations histopathologiques, Diagnostics différentiels

In 1988, the Bethesda system defined low and high grade squamous intraepithelial neoplasia. This terminology, and the subsequent classifications, is cytology-based and does not deal with the conceptual basis regarding squamous intraepithelial lesions and the subsequent development of cancer. The aim of this system was to standardise diagnostic reporting in cytology and to reduce inter-observer variability as well as to facilitate communication with clinicians, inter-laboratory comparison and statistical analysis. The cytological criteria in common between low and high grade lesions basically consist of nuclear changes (also known as dyskaryosis): increased nuclear size, irregular nuclear shape and contour, hyperchromatism, multinucleation, irregular chromatin distribution, abnormal nucleolar number, size and shape. Low grade squamous intraepithelial lesions include the cellular effects related to human papillomavirus (HPV) infection and cervical intraepithelial neoplasia grade I (CIN I). The cytological changes in this group are mild and are sometimes non-specific. The diagnosis can be uncertain or guarded. Some of these lesions are classified as ASCUS (Atypical Squamous Cells of Undeterined Significance). High grade squamous intraepithelial lesions include cervical intraepithelial neoplasia, grade II (CIN II) and cervical intraepithelial neoplasia grade III/carcinoma in-situ (CIN III). The diagnostic problems posed by these lesions are different from those in low grade lesions: the challenge is to not miss small cells, which can often be few in number but in which the cytological abnormalities are clearly evident. The terms low grade and high grade imply a different diagnosis and a different clinical evolution, but the clinician should be informed that the diagnosis suspected of these lesions should be confirmed by histological studies.

Nuclear envelope organization in papillary thyroid carcinoma.

Papillary thyroid carcinomas (PTCs) have characteristic nuclear shape changes compared to follicular-type thyroid epithelium. We tested the hypothesis that the altered nuclear shape results from altered distribution or expression of the major structural proteins of the nuclear envelope. Lamin A, lamin B1, lamin C, lamin B receptor (LBR), lamina-associated polypeptide 2 (LAP2), emerin, and nuclear pores were examined. PTC's with typical nuclear features by H&E were compared to non-neoplastic thyroid and follicular neoplasms using confocal microscopy, and semi-quantitative immunoblotting. Lamin A/C, lamin B1, LAP2, emerin, and nuclear pores all extend throughout the grooves and intranuclear inclusions of PTC. Their distribution and fluorescent intensity is not predictably altered relative to nuclear envelope irregularities. By immunoblotting, the abundance (per cell) and electrophoretic mobilities of lamin A, lamin B1, lamin C, emerin, and LAP2 proteins do not distinguish PTC, normal thyroid, or follicular neoplasms. These results do not support previously published predictions that lamin A/C expression is related to a loss of proliferative activity. At least three LAP2 isoforms are identified in normal and neoplastic thyroid. LBR is sparse or undetectable in all the thyroid samples. The results suggest that the irregular nuclear shape of PTC is not determined by these nuclear envelope structural proteins per se. We review the structure of the nuclear envelope, the major factors that determine nuclear shape, and the possible functional consequences of its alteration in PTC.

Discussion

Morphological changes of plasma cells (PC) are common in multiple myeloma (MM). Loss of round or oval nuclear shape has been related to cell malignancy in human, and we looked for the occurrence of such morphological change on PC from bone marrow (BM) smears in a retrospective series of 169 MM patients at diagnosis. Nuclear shape changes of PC differed according to the patients (notch, dumb-bell, folded or monocytoid appearance), even in the same patient; all subtypes were pooled and defined as PC with irregular nuclear shape (PCIN). A significant number of PCIN (≥5% of all BMPC) was found at diagnosis in 20.7%. Median survival was of 22 months for patients with ≥5% PCIN, and 41 months for others (p = 0.0001). Significant relationship was observed with prognostic parameters related intrinsic malignancy of the tumour process but not with beta-2-microglobulin (b2m). A clear-cut relationship was found also between PCIN and hypodiploidy (p = 0.0001), but not with deletion of chromosome 13. This study emphasises the relationship between PCIN, an easy-to-ascertain marker of intrinsic malignancy of the tumour process, and adverse prognosis.

In Vitro Studies of Cytotoxic Effect on Sarcoma-180 Cells of .BETA.-Subunit from Egg White Ovomucin.

When sarcoma-180 (SR-180) cells were incubated with α- or β-subunit prepared from insoluble ovomucin in the gel fraction of egg white, the cell proliferation rate was apparently reduced by the addition of β-subunit, while it was largely unaffected by α-subunit. Examinations by scanning and transmission electronmicroscopy indicated a dose- and time-dependent cytotoxic effect of β-subunit on SR-180 cells, whereas β-subunit did not injure mouse peritoneum macrophage used as normal cells. Ultrastructurally, SR-180 cells treated with β-subunit showed changes such as swelling and bleb formation of microvilli on cell membrane, irregular clumping of chromatin, irregular nuclear shape, and marked swelling of organelles in cytoplasm associated with cell degeneration in necrotic change. Furthermore, apoptotic analysis of the cultured SR-180 cells also demonstrated that β-subunit did not induce the apoptotic DNA fragmentation.

Alterations in F-actin distribution in cells treated with melatonin.

One of the possible pathways of action of melatonin is its effect on the cytoskeleton. In this work we looked for alterations in the cytoskeleton of cells treated with melatonin at physiological concentrations. T-47D, Hs-578T (human breast carcinoma cell lines), and MDCK (normal dog kidney) cells were maintained in MCDB 153 supplemented with 1% fetal bovine serum (FBS), or in Dulbecco's modified Eagle's medium (DMEM) supplemented with 5% FBS and treated with melatonin (10(-9) M or 10(-10) M) for 2 and 5 days, with or without 10(-8) M estradiol. F-actin was stained with phalloidin-fluorescein isothiocyanate (FITC). Cytokeratin 19 and beta-tubulin filaments were detected with specific monoclonal antibodies and secondary antibodies bound to FITC. Melatonin-treated T-47D cells observed in a transmission electronic microscope (TEM) showed an irregular nuclear shape and intermediate filaments disposed around the nucleus, which was not observed in control cells. Immunofluorescence analysis of cytokeratin filaments did not show significant differences between their distribution in control and treated cells. Melatonin did not induce significant alterations in cytokeratin filaments of T-47D, Hs578T or MDCK cells in DMEM and MCDB 153, or T-47D cells in DMEM. Melatonin induced the derangement of F-actin both in T-47D and MDCK cells kept in MCDB 153. The same was not observed when estradiol was also present. We did not observe significant alterations in the distribution of F-actin in T-47D or Hs-578T cells grown in DMEM. In DMEM, melatonin-treated MDCK cells were more elongated, with a slight concentration of F-actin on the cell boundary. Melatonin induced very slight alterations in microtubule organization of all cell lines studied.

Suppurative Granulomatous Lymphadenitis

The cellular composition of suppurative granulomas was investigated by the application of monoclonal and polyclonal antibodies to paraffin sections and compared with nonsuppurative, hypersensitivity-type granulomas. Macrophages, T cells, and dendritic cells showed a similar distribution in both types of granulomas. In addition to the presence of granulocytes, a major difference between suppurative granulomas and hypersensitive-type granulomas concerned their relationship with B lymphocytes. Hypersensitive-type granulomas were surrounded by small mantle B cells, but they did not contain any B lymphocytes. In contrast, variable numbers of B cells were found either at the periphery or in the center of suppurative granulomas. In view of their morphology (medium size, pale cytoplasm, irregular nuclear shape) and phenotype (L26 +/LN1 -/MB2 +/MT2 +) these B lymphocytes closely resembled monocytoid B cells. The monocytoid B cells might have a role in the recruitment of polymorphonuclear granulocytes and in the development of the necrosis, which occur within suppurative granulomas.

Congenital dyserythropoiesis and progressive alopecia in Polled Hereford calves: hematologic, biochemical, bone marrow cytologic, electrophoretic, and flow cytometric findings.

Congenital dyserythropoiesis with dyskeratosis is a slow, progressive, and often fatal disease in Polled Hereford calves. Affected calves have a macrocytic normochromic anemia with a mild reticulocytosis. Studies indicate that calves are hyperferremic with increased saturation of serum total iron binding capacity, which rules out iron deficiency as a cause. Other secondary causes of dyserythropoiesis, including cobalamin and folate deficiencies, are unlikely because serum cobalamin and folate levels of affected calves were normal. Virus isolation was negative, and failure to identify bovine retroviral antigens or antibodies from several calves suggested that viral agents were not involved. Bone marrow cytologic findings were similar to those in congenital hereditary dyserythropoiesis in humans and included occasional multinucleate cells, internuclear chromatin bridging between nuclei of partially divided cells, and, more frequently, irregular nuclear shapes and chromatin patterns. DNA content and cell cycle distribution of erythroid cells appeared normal, and no electrophoretic abnormalities were detected in erythrocyte membrane proteins. The Polled Hereford syndrome is similar in many ways to type I congenital dyserythropoiesis in humans and may be an appropriate biomedical model for studying erythroid proliferation during dyserythropoiesis.

The Ultrastructure of Dyserythropoiesis in Aplastic Anaemia

Electron microscopy of erythropoiesis in aplastic anaemia has demonstrated some unique features of dyserythropoiesis at the ultrastructural level, which contribute to understanding of the morphological features which are seen in the light microscope. The findings provide further evidence for the presence of qualitative defects in erythropoiesis in aplastic conditions. The alterations seen included bi- and multinucleated cells, intercellular bridges containing microtubules, internuclear chromatin bridges, irregular nuclear shapes, juxta-nuclear and peripheral cisternal structures, ringed sideroblasts, a diversity of intranuclear inclusions, nuclear clefts in both eu- and heterochromatin, and a variety of anomalies of the nuclear membrane. The significance of the occurrence of these anomalies in aplastic anaemia is considered and the role of the nuclear membrane and of endoplasmic reticulum in the pathogenesis of aplastic anaemia is discussed.