Cellular Characteristics (cellular + characteristic)

Distribution by Scientific Domains


Selected Abstracts


Cellular characteristics of non-allergic eosinophilic conjunctivitis

ACTA OPHTHALMOLOGICA, Issue 2 2010
Osmo Kari
Abstract. Purpose:, This study examines the histology of conjunctival biopsy samples from patients with persistent allergic eosinophilic conjunctivitis (AEC) or non-allergic eosinophilic conjunctivitis (NAEC). Methods:, Fourteen patients with conjunctivitis and eosinophilia in cytology samples were included in the study. Seven had positive skin-prick tests (the AEC group) and seven had negative skin-prick tests (the NAEC group). Eight asymptomatic subjects with negative skin-prick tests served as a control group. In conjunctival biopsies eosinophils were identified with monoclonal antibodies. Mast cells were identified by specific immunostaining and tryptase-positive granules were counted around them. The percentage of degranulated mast cells was used as a measure of cell activation. Eosinophil and goblet cell numbers were counted, epithelial thickness was measured, and the symptoms were characterized and graded. Results:, The numbers of eosinophils in biopsies were higher in patients with AEC than in healthy controls (p = 0.010). The proportion of activated mast cells tended to be higher in AEC patients (65%) than in NAEC patients (48%) or control subjects (40%). Patients with AEC had more goblet cells than control subjects (p = 0.049) and their epithelial layer was thicker (p = 0.054). Patients with AEC had more severe symptoms than control subjects (p = 0.0005), whereas the symptoms of NAEC patients did not differ statistically from those of controls (p = 0.065). Conclusions:, Patients with NAEC were characterized by mild eosinophilic inflammation and only minor structural conjunctival changes. The condition seems to run a relatively mild but persistent clinical course. [source]


Biodegradation and Cytocompatibility Studies of a Triphasic Ceramic-Coated Porous Hydroxyapatite for Bone Substitute Applications

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 1 2008
Annie John
Bone defects due to trauma or disease have led to the need for biomaterials as substitutes for tissue regeneration and repair. Herein, we introduce a porous triphasic ceramic-coated hydroxyapatite scaffold (HASi) for such applications. Interestingly, in the degradation experiments with isotonic buffer, HASi showed a significant release of silica with the disappearance of the tricalcium phosphate phase. Furthermore, the material also exhibited cytocompatibility with cultured bone marrow-derived mesenchymal stem cells of human origin. The material chemistry, together with the favorable cellular characteristics, indicates HASi as a promising candidate for critical-size bony defects, which still remains a formidable clinical challenge in the orthopedic scenario. [source]


Flow cytometric analysis of neural stem cells in the developing and adult mouse brain

JOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2002
Ayako Murayama
Abstract Despite recent progress in the neural stem cell biology, their cellular characteristics have not been described well. We investigated various characteristics of neural stem cells (NSCs) in vivo during CNS development, using FACS to identify the NSCs. We first examined stage-dependent changes in the physical parameters, using forward scatter (FSC) and side scatter (SSC) profiles, of NSCs from the developing striatum, where they appear to be active throughout the life of mammals. NSCs were divided into several fractions according to their FSC/SSC profile. With development, their number decreased in the FSChigh fractions but increased in the FSClow/SSChigh fraction, whereas NSCs were significantly concentrated in the fraction containing the largest cells (about 20 ,m in diameter) at any stage, which were mostly the cells with the highest nestin -enhancer activity. Furthermore, we demonstrated that, at all stages examined, the "side population" (SP), defined as the Hoechst 33342 low/negative fraction, which is known to be a stem cell-enriched population in bone marrow, was also enriched for Notch1-positive immature neural cells (about 60%) from the developing striatum. However, these immature SP cells were not detected in the large-cell fraction, however, but were concentrated instead in the FSClow/mid fractions. FACS analysis showed that SP cells from adults were included to some extent in the CD24low/PNAlow fraction, where NSCs were greatly concentrated. Collectively, the characteristics of NSCs were not uniform and changed developmentally. © 2002 Wiley-Liss, Inc. [source]


Effect of the Photoperiod and Administration of Melatonin on the Pars Tuberalis of Viscacha (Lagostomus maximus maximus): An Ultrastructural Study

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2010
Edith Perez Romera
Abstract The pituitary pars tuberalis (PT) is a glandular zone exhibiting well-defined structural characteristics. Morphologically, it is formed by specific secretory cells, folliculostellate cells, and migratory cells coming from the pars distalis. The purpose of this work was to investigate differences in specific cellular characteristics in the PT of viscachas captured in summer (long photoperiod) and winter (short photoperiod), as well as the effects of chronic melatonin administration in viscachas captured in summer and kept under long photoperiod. In summer, the PT-specific cells exhibited cell-like characteristics with an important secretory activity and a moderate amount of glycogen. In winter, the PT-specific granulated cells showed ultrastructural variations with signs of a reduced synthesis activity. Also, PT showed a high amount of glycogen and a great number of cells in degeneration. After melatonin administration, the ultrastructural characteristics were similar to those observed in winter, but the amount of glycogen was higher. These results suggest possible functional implications as a result of morphological differences between long and short photoperiods, and are in agreement with the variations of the pituitary-gonadal axis, probably in response to the natural photoperiod changes through the pineal melatonin. The ultrastructural differences observed in PT, after melatonin administration, were similar to those observed in the short photoperiod, thus supporting the hypothesis that these cytological changes are induced by melatonin. Anat Rec, 293:871,878, 2010. © 2010 Wiley-Liss, Inc. [source]


T1N0 Triple Negative Breast Cancer: Risk of Recurrence and Adjuvant Chemotherapy

THE BREAST JOURNAL, Issue 5 2009
Henry G. Kaplan MD
Abstract:, Adjuvant treatment of T1N0 breast cancer (BC) has evolved in recent years with chemotherapy options dependent on tumor size and cellular characteristics. Our goal is to describe the difference in outcome between T1N0 triple negative (TriNeg) and estrogen/progesterone receptor positive/her2/neu-negative BC. From our institute's registry, we identified primary BC patients diagnosed from 1998 to 2005, estrogen/progesterone receptor negative (ER,/PR,)/her-2/neu negative (her2,) (TriNeg = 110) and ER+/PR+/her2, (HR+/her2, = 919). Clinical diagnosis and treatment variables were chart abstracted. Vital and disease status were updated annually. Pearson chi-squared tests were used for bivariate analysis. Hazard ratios were calculated using the Cox proportional hazards model. Average patient age was 59 years, range 23,93 years and average length of follow-up was 4.22 years. T-stage distribution for HR+/her2, patients was 9% T1a (>0.1, ,0.5 cm), 34% T1b (>0.5 cm, ,1 cm), 57% T1c (>1 cm, ,2 cm) and for TriNeg, 6% T1a, 21% T1b, and 73% T1c. Sixty-five per cent of T1b and 73% T1c TriNeg patients received chemotherapy versus 7% of T1b and 32% of T1c HR+/her2, patients with TriNeg patients more likely to receive doxorubicin/cyclophosphamide/paclitaxel combined therapy. Recurrence rates were the following, T1b: 8.7%, TriNeg (2/23) versus 0%, HR+/her2, (0/315) and T1c: 8.8%, TriNeg (7/80) versus 2.1%, HR+/her2, (11/523). Five year relapse-free survival was 98% in the HR+/her2, group and 89% in the TriNeg group (log rank test = 27.77, p < 0.001). The hazard ratio for recurrence in the TriNeg group was 6.57 (95% CI = 2.34, 18.49) adjusted for age, tumor size, and adjuvant chemotherapy. Triple negative T1N0 patients have greater recurrence risk in spite of more aggressive therapy by both number treated and adjuvant chemotherapy type even in a low-risk category. New treatment modalities specific for triple negative disease are urgently needed. [source]


Photosynthetic Eukaryotes of Freshwater Wetland Biofilms: Adaptations and Structural Characteristics of the Extracellular Matrix in the Green Alga, Cosmarium reniforme (Zygnematophyceae, Streptophyta)

THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 4 2009
DAVID S. DOMOZYCH
ABSTRACT. Cosmarium reniforme (Zygnematophyceae, Streptophyta) is a green alga that is commonly found in biofilms of wetlands of the Adirondack region, NY (USA). Two distinctive characteristics that are critical to this alga's survival in a benthic biofilm are its elaborate cell morphology and extracellular matrix (ECM). In this study, ultrastructural, immunocytochemical, and experimental methodologies were employed in order to elucidate the cellular characteristics that are critical for survival in a biofilm. The ECM consists of a thick, outwardly lobed cell wall (CW), which contains a patterned network of structurally complex pores. Each pore consists of a narrow channel, terminating internally at a bulb that invaginates localized regions of the plasma membrane. The outer region of the pore contains arabinogalactan protein-like and extensin epitopes that are likely involved in adhesion mechanisms of the cell. External to the CW is the extracellular polymeric substance that is employed in ensheathment of the cell to the substrate and in gliding motility. The architectural design/biochemical make-up of the CW and a secretory system that encompasses the coordinated activities of the endomembrane and cytomotile/cytoskeletal systems provide the organism with effective mechanisms to support life within the biofilm complex. [source]


Recent Insights into PDGF-Induced Gliomagenesis

BRAIN PATHOLOGY, Issue 3 2010
Filippo Calzolari
Abstract Gliomas are aggressive and almost incurable glial brain tumors which frequently display abnormal platelet-derived growth factor (PDGF) signaling. Evidence gained from studies on several in vivo animal models has firmly established a causal connection between aberrant PDGF signaling and the formation of some gliomas. However, only recently has significant knowledge been gained regarding crucial issues such as the glioma cell of origin and the relationship between the transforming stimulus and the cellular characteristics of the resulting tumor. Based on recent evidence, we propose that PDGF can bias cell-fate decisions, driving the acquisition of cell type-specific features by the progeny of multipotent neural progenitors, thus determining the shape and direction of the transformation path. Furthermore, recent data about the cellular mechanisms of PDGF-driven glioma progression and maintenance indicate that PDGF may be required, unexpectedly, to override cell contact inhibition and promote glioma cell infiltration rather than to stimulate cell proliferation. [source]


Proliferation and pluripotency potential of ectomesenchymal cells derived from first branchial arch

CELL PROLIFERATION, Issue 2 2006
Yunfeng Lin
Their potential to be expanded in culture as a monolayer and to be induced into different cell lineages in vitro has not been previously reported in detail. In this study, the ectomesenchymal cells in the first branchial arch were enzymatically isolated from the mandibular processes of BALB/c mice and were maintained in an intact state in a medium containing leukaemia inhibitory factor. Here, we first evaluated the proliferative activity of the cells after the third passage, using bromodeoxyuridine labelling and in situ hybridization of telomerase mRNA. Positive staining for expression of HNK-1, S-100 and vimentin confirmed that the population of stem cells originated from the ectomesenchyme, which did not express cytokeratin. Then we investigated the molecular and cellular characteristics of the ectomesenchymal cells during their differentiation towards neurogenic, endothelial, myogenic and odontogenic lineages. Expression of multiple lineage-specific genes and proteins was detected by utilizing a range of molecular and biochemical approaches when the cells were transferred to inductive medium. Histological and immunohistochemical analysis of the induced cells at various intervals indicated obvious phenotypic alteration and presence of specific proteins for the differentiated lineages, for example nestin, factor VIII, ,-SMA and dentin sialophosphoprotein (DSPP), respectively. Correlatively, results of reverse transcription,PCR corroborated at mRNA level the expression of the characteristic molecules during differentiation. Therefore, it is suggested that the ectomesenchymal cells derived from the first branchial arch may represent a novel source of multipotential stem cells capable of undergoing expansion and variant differentiation in vitro. [source]


Feasibility of sputum induction in lung transplant recipients

CLINICAL TRANSPLANTATION, Issue 5 2004
Jan WK Van Den Berg
Abstract:, Sputum induction (SI) is nowadays being applied as a non-invasive and safe method to investigate airway inflammation in pulmonary diseases. We investigated the feasibility of SI after lung transplantation (LTX), and compared sputum and bronchoalveolar lavage (BAL) cellular characteristics and interleukin-8 (IL-8) levels. Results were also compared with 11 healthy subjects. SI as performed between 26 and 1947 d after LTX in 19 recipients, was successful in 16 of 22 attempts (73%). Six patients failed to produce sputum after induction, mostly just post-LTX and with having a lower forced expiratory volume in 1 s (FEV1). The success rate in clinically stable patients after the first month post-LTX was 93%. Side-effects were absent. Sputum recovery, viability and squamous cell contamination were comparable between LTX patients and healthy subjects. In the LTX group, total cell counts, neutrophil percentages and IL-8 levels were much higher in SI than BAL (1.6 × 106/mL, 65.5% and 54.2 ng/mL vs. 0.1 × 106/mL, 3.0% and 0.01 ng/mL; p < 0.001). Although LTX-neutrophil percentages in SI and BAL correlated properly (, = 0.72, p = 0.04), both techniques are not interchangeable. We conclude that sputum induction is feasible, well tolerated, and without major side-effects in stable patients after the first month post-LTX. Induced sputum may be a useful tool to study inflammatory changes of the airways after LTX, and because of the large quantity of neutrophils sampled, especially for further studies on the pathogenesis of bronchiolitis obliterans. [source]