Targeted inactivation of fh1 causes proliferative renal cyst development and activation of the hypoxia pathway.

PubMed

Pollard, Patrick J; Spencer-Dene, Bradley; Shukla, Deepa; Howarth, Kimberley; Nye, Emma; El-Bahrawy, Mona; Deheragoda, Maesha; Joannou, Maria; McDonald, Stuart; Martin, Alison; Igarashi, Peter; Varsani-Brown, Sunita; Rosewell, Ian; Poulsom, Richard; Maxwell, Patrick; Stamp, Gordon W; Tomlinson, Ian P M

2007-04-01

Germline mutations in the fumarate hydratase (FH) tumor suppressor gene predispose to leiomyomatosis, renal cysts, and renal cell cancer (HLRCC). HLRCC tumors overexpress HIF1alpha and hypoxia pathway genes. We conditionally inactivated mouse Fh1 in the kidney. Fh1 mutants developed multiple clonal renal cysts that overexpressed Hif1alpha and Hif2alpha. Hif targets, such as Glut1 and Vegf, were upregulated. We found that Fh1-deficient murine embryonic stem cells and renal carcinomas from HLRCC showed similar overexpression of HIF and hypoxia pathway components to the mouse cysts. Our data have shown in vivo that pseudohypoxic drive, resulting from HIF1alpha (and HIF2alpha) overexpression, is a direct consequence of Fh1 inactivation. Our mouse may be useful for testing therapeutic interventions that target angiogenesis and HIF-prolyl hydroxylation.

The novel tumour suppressor Madm regulates stem cell competition in the Drosophila testis

PubMed Central

Singh, Shree Ram; Liu, Ying; Zhao, Jiangsha; Zeng, Xiankun; Hou, Steven X.

2016-01-01

Stem cell competition has emerged as a mechanism for selecting fit stem cells/progenitors and controlling tumourigenesis. However, little is known about the underlying molecular mechanism. Here we identify Mlf1-adaptor molecule (Madm), a novel tumour suppressor that regulates the competition between germline stem cells (GSCs) and somatic cyst stem cells (CySCs) for niche occupancy. Madm knockdown results in overexpression of the EGF receptor ligand vein (vn), which further activates EGF receptor signalling and integrin expression non-cell autonomously in CySCs to promote their overproliferation and ability to outcompete GSCs for niche occupancy. Conversely, expressing a constitutively activated form of the Drosophila JAK kinase (hopTum−l) promotes Madm nuclear translocation, and suppresses vn and integrin expression in CySCs that allows GSCs to outcompete CySCs for niche occupancy and promotes GSC tumour formation. Tumour suppressor-mediated stem cell competition presented here could be a mechanism of tumour initiation in mammals. PMID:26792023

The novel tumour suppressor Madm regulates stem cell competition in the Drosophila testis.

PubMed

Singh, Shree Ram; Liu, Ying; Zhao, Jiangsha; Zeng, Xiankun; Hou, Steven X

2016-01-21

Stem cell competition has emerged as a mechanism for selecting fit stem cells/progenitors and controlling tumourigenesis. However, little is known about the underlying molecular mechanism. Here we identify Mlf1-adaptor molecule (Madm), a novel tumour suppressor that regulates the competition between germline stem cells (GSCs) and somatic cyst stem cells (CySCs) for niche occupancy. Madm knockdown results in overexpression of the EGF receptor ligand vein (vn), which further activates EGF receptor signalling and integrin expression non-cell autonomously in CySCs to promote their overproliferation and ability to outcompete GSCs for niche occupancy. Conversely, expressing a constitutively activated form of the Drosophila JAK kinase (hop(Tum-l)) promotes Madm nuclear translocation, and suppresses vn and integrin expression in CySCs that allows GSCs to outcompete CySCs for niche occupancy and promotes GSC tumour formation. Tumour suppressor-mediated stem cell competition presented here could be a mechanism of tumour initiation in mammals.

Intrinsic epidermoid of the brain stem: case report and review of the literature.

PubMed

Singh, Saraj K; Jain, Kapil; Jain, Vijendra Kumar

2018-03-19

Purely cystic brain stem epidermoid is a rare diagnosis among all brainstem cystic lesions. Further, it is very rare in pediatric age group. Here, we are reporting a rare case of completely cystic brain stem epidermoid in a child. The patient presented with clinical features of brain stem involvement. MRI brain was suggestive of cystic brain stem lesion. Patient went through surgical procedure. Final diagnosis of epidermoid cyst was confirmed on histopathological report. With the help of various advanced sequences of MRI like diffusion and ADC, diagnosis of epidermoid cyst can be established at unusual intracranial site also. Surgical resection of epidermoid cyst at brain stem should be attempted judiciously utilizing all modern tools of neurosurgery.

Organoid cystogenesis reveals a critical role of microenvironment in human polycystic kidney disease

NASA Astrophysics Data System (ADS)

Cruz, Nelly M.; Song, Xuewen; Czerniecki, Stefan M.; Gulieva, Ramila E.; Churchill, Angela J.; Kim, Yong Kyun; Winston, Kosuke; Tran, Linh M.; Diaz, Marco A.; Fu, Hongxia; Finn, Laura S.; Pei, York; Himmelfarb, Jonathan; Freedman, Benjamin S.

2017-11-01

Polycystic kidney disease (PKD) is a life-threatening disorder, commonly caused by defects in polycystin-1 (PC1) or polycystin-2 (PC2), in which tubular epithelia form fluid-filled cysts. A major barrier to understanding PKD is the absence of human cellular models that accurately and efficiently recapitulate cystogenesis. Previously, we have generated a genetic model of PKD using human pluripotent stem cells and derived kidney organoids. Here we show that systematic substitution of physical components can dramatically increase or decrease cyst formation, unveiling a critical role for microenvironment in PKD. Removal of adherent cues increases cystogenesis 10-fold, producing cysts phenotypically resembling PKD that expand massively to 1-centimetre diameters. Removal of stroma enables outgrowth of PKD cell lines, which exhibit defects in PC1 expression and collagen compaction. Cyclic adenosine monophosphate (cAMP), when added, induces cysts in both PKD organoids and controls. These biomaterials establish a highly efficient model of PKD cystogenesis that directly implicates the microenvironment at the earliest stages of the disease.

Fetal bovine serum simultaneously stimulates apoptosis and DNA synthesis in premeiotic stages of spermatogenesis in spiny dogfish (Squalus acanthias) in vitro: modulation by androgen and spermatogenic activity status.

PubMed

McClusky, Leon Mendel

2008-05-01

Using the simple cystic spermatogenesis in the shark testis as a model, we previously reported the relative resistance of immature spermatogonia (stem cell and early-stage spermatogonia) to apoptosis in the normal testis and after spermatoxicant exposure in vivo. Apoptosis was monitored by fluorescence image analysis of living cysts, using the validated acridine orange (AO) vital staining technique. Findings show that FBS simultaneously stimulates both apoptosis and [(3)H]thymidine incorporation in immature spermatogonial clones in a concentration-dependent manner in vitro. Furthermore, androgen inhibits apoptosis and increases cyst viability, more so with 10% FBS than with 1% FBS. All the effects were as a function of spermatogenic activity status but were distinct in early-stage spermatogonial cysts isolated from testes awakening from the previous winter spermatogenic arrest period. Results are discussed in the context of the alternating germ-Sertoli cell population kinetics of early-stage spermatogonial cysts in Squalus acanthias's protracted testicular cycle.

Defined Medium Conditions for the Induction and Expansion of Human Pluripotent Stem Cell-Derived Retinal Pigment Epithelium.

PubMed

Lidgerwood, Grace E; Lim, Shiang Y; Crombie, Duncan E; Ali, Ray; Gill, Katherine P; Hernández, Damián; Kie, Josh; Conquest, Alison; Waugh, Hayley S; Wong, Raymond C B; Liang, Helena H; Hewitt, Alex W; Davidson, Kathryn C; Pébay, Alice

2016-04-01

We demonstrate that a combination of Noggin, Dickkopf-1, Insulin Growth Factor 1 and basic Fibroblast Growth Factor, promotes the differentiation of human pluripotent stem cells into retinal pigment epithelium (RPE) cells. We describe an efficient one-step approach that allows the generation of RPE cells from both human embryonic stem cells and human induced pluripotent stem cells within 40-60 days without the need for manual excision, floating aggregates or imbedded cysts. Compared to methods that rely on spontaneous differentiation, our protocol results in faster differentiation into RPE cells. This pro-retinal culture medium promotes the growth of functional RPE cells that exhibit key characteristics of the RPE including pigmentation, polygonal morphology, expression of mature RPE markers, electrophysiological membrane potential and the ability to phagocytose photoreceptor outer segments. This protocol can be adapted for feeder, feeder-free and serum-free conditions. This method thereby provides a rapid and simplified production of RPE cells for downstream applications such as disease modelling and drug screening.

Multiscale microenvironmental perturbation of pluripotent stem cell fate and self-organization

NASA Astrophysics Data System (ADS)

Tabata, Yoji; Lutolf, Matthias P.

2017-03-01

The combination of microfluidics with engineered three-dimensional (3D) matrices can bring new insights into the fate regulation of stem cells and their self-organization into organoids. Although there has been progress in 3D stem cell culturing, most existing in vitro methodologies do not allow for mimicking of the spatiotemporal heterogeneity of stimuli that drive morphogenetic processes in vivo. To address this, we present a perfusion-free microchip concept for the in vitro 3D perturbation of stem cell fate. Stem cells are encapsulated in a hydrogel compartment that is flanked by open reservoirs for the diffusion-driven generation of biomolecule gradients. Juxtaposing additional compartments bearing supportive cells enables investigating the influence of long range cell-cell communication. We explore the utility of the microchips in manipulating early fate choices and self-organizing characteristics of 3D-cultured mouse embryonic stem cells (mESCs) under neural differentiation conditions and exposure to gradients of leukemia inhibitory factor (LIF). mESCs respond to LIF gradients in a spatially dependent manner. At higher LIF concentrations, multicellular colonies maintain pluripotency in contrast, at lower concentrations, mESCs develop into apicobasally polarized epithelial cysts. This versatile system can help to systematically explore the role of multifactorial microenvironments in promoting self-patterning of various stem cell types.

The nuclear lamina regulates germline stem cell niche organization via modulation of EGFR signaling.

PubMed

Chen, Haiyang; Chen, Xin; Zheng, Yixian

2013-07-03

Stem cell niche interactions have been studied extensively with regard to cell polarity and extracellular signaling. Less is known about the way in which signals and polarity cues integrate with intracellular structures to ensure appropriate niche organization and function. Here, we report that nuclear lamins function in the cyst stem cells (CySCs) of Drosophila testes to control the interaction of CySCs with the hub. This interaction is important for regulation of CySC differentiation and organization of the niche that supports the germline stem cells (GSCs). Lamin promotes nuclear retention of phosphorylated ERK in the CySC lineage by regulating the distribution of specific nucleoporins within the nuclear pores. Lamin-regulated nuclear epidermal growth factor (EGF) receptor signaling in the CySC lineage is essential for proliferation and differentiation of the GSCs and the transient amplifying germ cells. Thus, we have uncovered a role for the nuclear lamina in the integration of EGF signaling to regulate stem cell niche function. Copyright © 2013 Elsevier Inc. All rights reserved.

Enhanced resistance to soybean cyst nematode Heterodera glycines in transgenic soybean by silencing putative CLE receptors

USDA-ARS?s Scientific Manuscript database

CLE peptides are small extracellular proteins important in regulating plant meristematic activity through the CLE-receptor kinase-WOX signaling module. Stem cell pools in the SAM (shoot apical meristem), RAM (root apical meristem), and vascular cambium are tightly controlled by CLE signaling pathway...

Expression of the stem cell factor in fibroblasts, endothelial cells, and macrophages in periapical tissues in human chronic periapical diseases.

PubMed

Shen, S Q; Wang, R; Huang, S G

2017-03-08

Stem cell factor (SCF), an important stem cell cytokine, has multiple functions. Fibroblasts (FBs), mature mast cells, endothelial cells (ECs), and eosinophil granulocytes can produce SCF in the inflammatory process. Therefore, we aimed to observe SCF expression in FBs, ECs, and macrophages (MPs) in periapical tissues in human chronic periapical disease and investigate the effects of cells expressing SCF in pathogenesis of the disease. Healthy (N = 20), periapical cyst (N = 15), and periapical granuloma (N = 15) tissues were fixed in 10% formalin for 48 h, embedded in paraffin, and stained with hematoxylin and eosin to observe histological changes. SCF expression was observed in FBs, ECs, and MPs in periapical tissues by double immunofluorescence. CD334, CD31, and CD14 are specific markers of FBs, ECs, and MPs, respectively. Results showed that densities of CD334-SCF double-positive FBs, CD31-SCF double-positive ECs, and CD14-SCF double-positive MPs were significantly increased in periapical tissue groups (P < 0.01). There were no significant differences in CD334-SCF double-positive FB and CD31-SCF double-positive EC levels between the two periapical tissue groups (P > 0.05). CD14-SCF double-positive MP density was considerably higher in periapical granulomas than in cysts (P < 0.01). FB, EC, and MP levels were significantly high and densities of CD334-SCF double-positive FBs, CD31-SCF double-positive ECs, and CD14-SCF double-positive MPs improved considerably in chronic periapical tissues, suggesting that the cells might be related to occurrence, development, and pathogenesis of chronic periapical disease.

Morphology and ultrastructure of the germarium in panoistic ovarioles of a basal "apterygotous" insect, Thermobia domestica.

PubMed

Tworzydlo, Waclaw; Kisiel, Elzbieta; Jankowska, Wladyslawa; Bilinski, Szczepan M

2014-06-01

It has been shown that in Drosophila the germline stem cells (GSCs), similar to the germline and non-germline stem cells of other species, develop and function in specialized microenvironments formed by somatic cells, referred to as the niches. In the fruit fly ovaries, the female GSCs divide asymmetrically to produce new GSCs and the progenitor cells, the cystoblasts (Cbs). Each Cb then divides to generate the cyst composed of 16 interconnected sibling cells, the cystocytes. After cyst formation, specific molecules are transferred to one of the cystocytes which differentiates into the oocyte, whereas the other 15 cystocytes become the nurse cells. We have studied morphology and ultrastructure of the germaria in the ovarioles (ovaries) of a basal "apterygotous" insect, the firebrat (Thermobia domestica). Our analyses have revealed that in this insect, putative GSCs are present along the anterior apex of the germarium. These cells are separated from each other and from the basement lamina covering the ovariole by characteristic somatic cells, termed the apical somatic cells (ASCs), or their elongated processes. We believe that all the ASCs of a given ovariole constitute a "dispersed" niche in which putative GSCs are anchored. Our analyses have additionally shown that in Thermobia, both the Cbs and young (meiotic) oocytes are always individual and never form syncytial cysts. These findings indicate that in certain basal insects the syncytial phase of oogenesis has been eliminated during evolution. Finally, we show that in the early meiotic oocytes of Thermobia, during the so-called bouquet stage, prominent Balbiani bodies (Bbs) are formed. Analysis of serial micrographs indicates that the Bbs invariably arise next to the segment of the nuclear envelope to which the telomeres of the bouquet chromosomes are attached. We suggest, in the light of these data, that the localization of the Bb together with the polar attachment of the bouquet chromosomes play a crucial role in the early asymmetrization of Thermobia oocytes. Copyright © 2014 Elsevier GmbH. All rights reserved.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)-mediated deregulation of myeloid and sebaceous gland stem/progenitor cell homeostasis.

PubMed

Bock, Karl Walter

2017-06-01

Studies of TCDD toxicity stimulated identification of the responsible aryl hydrocarbon receptor (AHR), a multifunctional, ligand-activated transcription factor of the basic helix-loop-helix/Per-Arnt-Sim family. Accumulating evidence suggests a role of this receptor in homeostasis of stem/progenitor cells, in addition to its known role in xenobiotic metabolism. (1) Regulation of myelopoiesis is complex. As one example, AHR-mediated downregulation of human CD34+ progenitor differentiation to monocytes/macrophages is discussed. (2) Accumulation of TCDD in sebum leads to deregulation of sebocyte differentiation via Blimp1-mediated inhibition of c-Myc signaling and stimulation of Wnt-mediated proliferation of interfollicular epidermis. The resulting sebaceous gland atrophy and formation of dermal cysts may explain the pathogenesis of chloracne, the hallmark of TCDD toxicity. (3) TCDD treatment of confluent liver stem cell-like rat WB-F344 cells leads to release from cell-cell contact inhibition via AHR-mediated crosstalk with multiple signaling pathways. Further work is needed to delineate AHR function in crosstalk with other signaling pathways.

Generation of induced pluripotent stem cells derived from an autosomal dominant polycystic kidney disease patient with a p.Ser1457fs mutation in PKD1.

PubMed

Huang, Ching-Ying; Ho, Ming-Ching; Lee, Jia-Jung; Hwang, Daw-Yang; Ko, Hui-Wen; Cheng, Yu-Che; Hsu, Yu-Hung; Lu, Huai-En; Chen, Hung-Chun; Hsieh, Patrick C H

2017-10-01

Autosomal dominant polycystic kidney disease is one of the most prevalent forms of inherited cystic kidney disease, and can be characterized by kidney cyst formation and enlargement. Here we report the generation of a Type 1 ADPKD disease iPS cell line, IBMS-iPSC-012-12, which retains the conserved deletion of PKD1, normal karyotype and exhibits the properties of pluripotent stem cells such as ES-like morphology, expression of pluripotent markers and capacity to differentiate into all three germ layers. Our results show that we have successfully generated a patient-specific iPS cell line with a mutation in PKD1 for study of renal disease pathophysiology. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Male gametogenesis without centrioles.

PubMed

Riparbelli, Maria Giovanna; Callaini, Giuliano

2011-01-15

The orientation of the mitotic spindle plays a central role in specifying stem cell-renewal by enabling interaction of the daughter cells with external cues: the daughter cell closest to the hub region is instructed to self-renew, whereas the distal one starts to differentiate. Here, we have analyzed male gametogenesis in DSas-4 Drosophila mutants and we have reported that spindle alignment and asymmetric divisions are properly executed in male germline stem cells that lack centrioles. Spermatogonial divisions also correctly proceed in the absence of centrioles, giving rise to cysts of 16 primary spermatocytes. By contrast, abnormal meiotic spindles assemble in primary spermatocytes. These results point to different requirements for centrioles during male gametogenesis of Drosophila. Spindle formation during germ cell mitosis may be successfully supported by an acentrosomal pathway that is inadequate to warrant the proper execution of meiosis. Copyright © 2010 Elsevier Inc. All rights reserved.

Unlimited in vitro expansion of adult bi-potent pancreas progenitors through the Lgr5/R-spondin axis

PubMed Central

Huch, Meritxell; Bonfanti, Paola; Boj, Sylvia F; Sato, Toshiro; Loomans, Cindy J M; van de Wetering, Marc; Sojoodi, Mozhdeh; Li, Vivian S W; Schuijers, Jurian; Gracanin, Ana; Ringnalda, Femke; Begthel, Harry; Hamer, Karien; Mulder, Joyce; van Es, Johan H; de Koning, Eelco; Vries, Robert G J; Heimberg, Harry; Clevers, Hans

2013-01-01

Lgr5 marks adult stem cells in multiple adult organs and is a receptor for the Wnt-agonistic R-spondins (RSPOs). Intestinal, stomach and liver Lgr5+ stem cells grow in 3D cultures to form ever-expanding organoids, which resemble the tissues of origin. Wnt signalling is inactive and Lgr5 is not expressed under physiological conditions in the adult pancreas. However, we now report that the Wnt pathway is robustly activated upon injury by partial duct ligation (PDL), concomitant with the appearance of Lgr5 expression in regenerating pancreatic ducts. In vitro, duct fragments from mouse pancreas initiate Lgr5 expression in RSPO1-based cultures, and develop into budding cyst-like structures (organoids) that expand five-fold weekly for >40 weeks. Single isolated duct cells can also be cultured into pancreatic organoids, containing Lgr5 stem/progenitor cells that can be clonally expanded. Clonal pancreas organoids can be induced to differentiate into duct as well as endocrine cells upon transplantation, thus proving their bi-potentiality. PMID:24045232

The Drosophila BCL6 homolog Ken and Barbie promotes somatic stem cell self-renewal in the testis niche.

PubMed

Issigonis, Melanie; Matunis, Erika

2012-08-15

Stem cells sustain tissue regeneration by their remarkable ability to replenish the stem cell pool and to generate differentiating progeny. Signals from local microenvironments, or niches, control stem cell behavior. In the Drosophila testis, a group of somatic support cells called the hub creates a stem cell niche by locally activating the Janus Kinase-Signal Transducer and Activator of Transcription (JAK-STAT) pathway in two adjacent types of stem cells: germline stem cells (GSCs) and somatic cyst stem cells (CySCs). Here, we find that ken and barbie (ken) is autonomously required for the self-renewal of CySCs but not GSCs. Furthermore, Ken misexpression in the CySC lineage induces the cell-autonomous self-renewal of somatic cells as well as the nonautonomous self-renewal of germ cells outside the niche. Thus, Ken, like Stat92E and its targets ZFH1 (Leatherman and Dinardo, 2008) and Chinmo (Flaherty et al., 2010), is necessary and sufficient for CySC renewal. However, ken is not a JAK-STAT target in the testis, but instead acts in parallel to Stat92E to ensure CySC self-renewal. Ken represses a subset of Stat92E targets in the embryo (Arbouzova et al., 2006) suggesting that Ken maintains CySCs by repressing differentiation factors. In support of this hypothesis, we find that the global JAK-STAT inhibitor Protein tyrosine phosphatase 61F (Ptp61F) is a JAK-STAT target in the testis that is repressed by Ken. Together, our work demonstrates that Ken has an important role in the inhibition of CySC differentiation. Studies of ken may inform our understanding of its vertebrate orthologue B-Cell Lymphoma 6 (BCL6) and how misregulation of this oncogene leads to human lymphomas. Copyright © 2012 Elsevier Inc. All rights reserved.

Derivation and characterization of hepatic progenitor cells from human embryonic stem cells.

PubMed

Zhao, Dongxin; Chen, Song; Cai, Jun; Guo, Yushan; Song, Zhihua; Che, Jie; Liu, Chun; Wu, Chen; Ding, Mingxiao; Deng, Hongkui

2009-07-31

The derivation of hepatic progenitor cells from human embryonic stem (hES) cells is of value both in the study of early human liver organogenesis and in the creation of an unlimited source of donor cells for hepatocyte transplantation therapy. Here, we report for the first time the generation of hepatic progenitor cells derived from hES cells. Hepatic endoderm cells were generated by activating FGF and BMP pathways and were then purified by fluorescence activated cell sorting using a newly identified surface marker, N-cadherin. After co-culture with STO feeder cells, these purified hepatic endoderm cells yielded hepatic progenitor colonies, which possessed the proliferation potential to be cultured for an extended period of more than 100 days. With extensive expansion, they co-expressed the hepatic marker AFP and the biliary lineage marker KRT7 and maintained bipotential differentiation capacity. They were able to differentiate into hepatocyte-like cells, which expressed ALB and AAT, and into cholangiocyte-like cells, which formed duct-like cyst structures, expressed KRT19 and KRT7, and acquired epithelial polarity. In conclusion, this is the first report of the generation of proliferative and bipotential hepatic progenitor cells from hES cells. These hES cell-derived hepatic progenitor cells could be effectively used as an in vitro model for studying the mechanisms of hepatic stem/progenitor cell origin, self-renewal and differentiation.

ALIX and ESCRT-III Coordinately Control Cytokinetic Abscission during Germline Stem Cell Division In Vivo

PubMed Central

Eikenes, Åsmund H.; Malerød, Lene; Christensen, Anette Lie; Steen, Chloé B.; Mathieu, Juliette; Nezis, Ioannis P.; Liestøl, Knut; Huynh, Jean-René; Stenmark, Harald; Haglund, Kaisa

2015-01-01

Abscission is the final step of cytokinesis that involves the cleavage of the intercellular bridge connecting the two daughter cells. Recent studies have given novel insight into the spatiotemporal regulation and molecular mechanisms controlling abscission in cultured yeast and human cells. The mechanisms of abscission in living metazoan tissues are however not well understood. Here we show that ALIX and the ESCRT-III component Shrub are required for completion of abscission during Drosophila female germline stem cell (fGSC) division. Loss of ALIX or Shrub function in fGSCs leads to delayed abscission and the consequent formation of stem cysts in which chains of daughter cells remain interconnected to the fGSC via midbody rings and fusome. We demonstrate that ALIX and Shrub interact and that they co-localize at midbody rings and midbodies during cytokinetic abscission in fGSCs. Mechanistically, we show that the direct interaction between ALIX and Shrub is required to ensure cytokinesis completion with normal kinetics in fGSCs. We conclude that ALIX and ESCRT-III coordinately control abscission in Drosophila fGSCs and that their complex formation is required for accurate abscission timing in GSCs in vivo. PMID:25635693

Data Mining Feature Subset Weighting and Selection Using Genetic Algorithms

DTIC Science & Technology

2002-03-01

seed-stain, anthracnose, phyllosticta-leaf-spot, alternarialeaf-spot, frog-eye-leaf- spot, diaporthe-pod-&-stem-blight, cyst - nematode , 2-4-d-injury...seed-discolor: absent,present,?. 33. seed-size: norm,lt-norm,?. 34. shriveling: absent,present,?. 35. roots: norm,rotted,galls- cysts

Comparison of Mast Cells Count in Odontogenic Cysts Using Histochemical Staining.

PubMed

Rajabi-Moghaddam, Mahdieh; Abbaszadeh-Bidokhty, Hamid; Bijani, Ali

2015-01-01

Odontogenic cysts are among the most frequent destructive lesions of jaws which their pathogenesis and growth mechanism are not cleared. With respect to different roles of mast cells, they may play a role in the pathogenesis and growth of odontogenic cysts. The aim of present study was to evaluate mast cells in the most common odontogenic cyst. Thirty paraffin-embedded tissue blocks including 10 radicular cysts, 10 dentigerous cysts and 10 odontogenic keratocysts were used and 5 micron sections stained with toluidine blue and observed by light microscope under ×400 magnification to evaluate mast cells within these cysts. For each case, 5 high-power field areas, selected from hot-spot areas, were considered and each area divided into 3 zones: intra-epithelial zone, sub-epithelial zone and deep zone. Most of the studied cyst showed presence of mast cells. There was not any significant difference in mast cell count between studied cysts ( P -values > 0.05).With respect to intra-epithelial, sub-epithelial and deep zones, there was not any significant difference between three studied cysts. There was not any significant difference between sub-epithelial zone and deep zone within each of these cysts. There was only significant difference between intra-epithelial zone and sub-epithelial zone within dentigerous cysts and odontogenic keratocysts ( P -value < 0.05). Prevalence of mast cells in fibrous wall of odontogenic cysts suggests their activity in these cysts. Mast cells may not be directly involved in the pathogenesis of odontogenic keratocysts.

Environmental pollution and acne: Chloracne.

PubMed

Ju, Qiang; Zouboulis, Christos C; Xia, Longqing

2009-05-01

Environmental pollutants can result in a variant of acne called 'chloracne'. Chloracne is caused by systemic exposure to certain halogenated aromatic hydrocarbons 'chloracnegens', and is considered to be one of the most sensitive indicators of systemic poisoning by these compounds. Dioxin is the most potent environmental chloracnegen. Most cases of chloracne have resulted from occupational and non-occupational exposures, non-occupational chloracne mainly resulted from contaminated industrial wastes and contaminated food products. Non-inflammatory comedones and straw-colored cysts are the primary clinical manifestation of chloracne. Increasing of cysts in number is a signal of aggravation of chloracne. Generalized lesions can appear on the face, neck, trunk, exterimities, genitalia, axillary and other areas. Course of chloracne is chronic. Severity of chloracne is related to dosage of exposed chloracnegens, chloracnegenic potency and individual susceptibility. Histopathology of chloracne is characterized mainly by hyperplasia of epidermal cell, while follicular and sebaceous gland are taken placed by keratinized epidermal cell. The pathogenesis of chloracne maybe related to the imbalance of epidermal stem cell. Chloracne appears to be resistant to all tested forms of treatment. The only way to control chloracne is to prevent exposure to chloracnegens.

Comparison of Mast Cells Count in Odontogenic Cysts Using Histochemical Staining

PubMed Central

Rajabi-Moghaddam, Mahdieh; Abbaszadeh-Bidokhty, Hamid; Bijani, Ali

2015-01-01

Background & Objectives: Odontogenic cysts are among the most frequent destructive lesions of jaws which their pathogenesis and growth mechanism are not cleared. With respect to different roles of mast cells, they may play a role in the pathogenesis and growth of odontogenic cysts. The aim of present study was to evaluate mast cells in the most common odontogenic cyst. Methods: Thirty paraffin-embedded tissue blocks including 10 radicular cysts, 10 dentigerous cysts and 10 odontogenic keratocysts were used and 5 micron sections stained with toluidine blue and observed by light microscope under ×400 magnification to evaluate mast cells within these cysts. For each case, 5 high-power field areas, selected from hot-spot areas, were considered and each area divided into 3 zones: intra-epithelial zone, sub-epithelial zone and deep zone. Results: Most of the studied cyst showed presence of mast cells. There was not any significant difference in mast cell count between studied cysts ( P -values > 0.05).With respect to intra-epithelial, sub-epithelial and deep zones, there was not any significant difference between three studied cysts. There was not any significant difference between sub-epithelial zone and deep zone within each of these cysts. There was only significant difference between intra-epithelial zone and sub-epithelial zone within dentigerous cysts and odontogenic keratocysts ( P -value < 0.05). Conclusions: Prevalence of mast cells in fibrous wall of odontogenic cysts suggests their activity in these cysts. Mast cells may not be directly involved in the pathogenesis of odontogenic keratocysts. PMID:26351470

Stem cells and fluid flow drive cyst formation in an invertebrate excretory organ

PubMed Central

Thi-Kim Vu, Hanh; Rink, Jochen C; McKinney, Sean A; McClain, Melainia; Lakshmanaperumal, Naharajan; Alexander, Richard; Sánchez Alvarado, Alejandro

2015-01-01

Cystic kidney diseases (CKDs) affect millions of people worldwide. The defining pathological features are fluid-filled cysts developing from nephric tubules due to defective flow sensing, cell proliferation and differentiation. The underlying molecular mechanisms, however, remain poorly understood, and the derived excretory systems of established invertebrate models (Caenorhabditis elegans and Drosophila melanogaster) are unsuitable to model CKDs. Systematic structure/function comparisons revealed that the combination of ultrafiltration and flow-associated filtrate modification that is central to CKD etiology is remarkably conserved between the planarian excretory system and the vertebrate nephron. Consistently, both RNA-mediated genetic interference (RNAi) of planarian orthologues of human CKD genes and inhibition of tubule flow led to tubular cystogenesis that share many features with vertebrate CKDs, suggesting deep mechanistic conservation. Our results demonstrate a common evolutionary origin of animal excretory systems and establish planarians as a novel and experimentally accessible invertebrate model for the study of human kidney pathologies. DOI: http://dx.doi.org/10.7554/eLife.07405.001 PMID:26057828

Investigation of tissue cysts in the retina in a mouse model of ocular toxoplasmosis: distribution and interaction with glial cells.

PubMed

Song, Hyun Beom; Jung, Bong-Kwang; Kim, Jin Hyoung; Lee, Young-Ha; Choi, Min-Ho; Kim, Jeong Hun

2018-06-02

The conversion of tachyzoites into bradyzoites is a way for Toxoplasma gondii to establish a chronic and asymptomatic infection and achieve lifelong persistence in the host. The bradyzoites form tissue cysts in the retina, but not much is known about the horizontal distribution of the cysts or their interactions with glial cells in the retina. A chronic ocular toxoplasmosis model was induced by per oral administration of T. gondii Me49 strain cysts to BALB/c mice. Two months after the infection, retinas were flat-mounted and immunostained to detect cysts, ganglion cells, Müller cells, astrocytes, and microglial cells, followed by observation under fluorescence and confocal microscope. The horizontal distribution showed a rather clustered pattern, but the clusters were not restricted to certain location of the retina. Axial distribution was confined to the inner retina, mostly in ganglion cell layer or the inner plexiform layer. Both ganglion cells, a type of retinal neurons, and Müller cells, predominant retinal glial cells, could harbor cysts. The cysts were spatially separated from astrocytes, the most abundant glial cells in the ganglion cell layer, while close spatial distribution of microglial cells was observed in two thirds of retinal cysts. In this study, we demonstrated that the retinal cysts were not evenly distributed horizontally and were confined to the inner retina axially. Both neurons and one type of glial cells could harbor cysts, and topographic analysis of other glial cells suggests role of microglial cells in chronic ocular toxoplasmosis.

Mucoepidermoid carcinoma in a salivary duct cyst of the parotid gland. Contribution to the development of tumours in salivary gland cysts.

PubMed

Seifert, G

1996-12-01

Concerning the hypothesis that distinct types of salivary gland cysts may be the starting point of a salivary gland tumour, a histological examination of 1,661 salivary gland cysts was performed in order to analyse the cell types and their proliferative activity. Epithelial alterations were found especially in salivary duct cysts of parotid gland and in mucous retention cysts of minor salivary glands. Characteristic cellular changes were epithelial metaplasias (goblet cells, clear cells, squamous cells) and focal epithelial proliferations with plump or papillary plaques projecting into the cyst lumen. Only in one case had a mucoepidermoid carcinoma developed in the wall of a parotid duct cyst. The epithelial metaplasia and focal proliferative activity in salivary duct cysts is comparable to similar alterations in odontogenic cysts as possible early manifestation of a tumour, especially of an ameloblastoma or mucoepidermoid carcinoma. The differential diagnosis of salivary duct cysts must take primarily cystadenomas and cystic mucoepidermoid carcinomas of well-differentiated type into account.

Life cycle and control of the cyst nematode Heterodera goldeni on rice in Egypt

USDA-ARS?s Scientific Manuscript database

The life cycle and methods for control of the cyst nematode Heterodera goldeni on rice (Oryza sativa) were examined in the greenhouse. Three tests were conducted to study the effects of soil treatments with some plant materials, stems of oyster mushroom (Pleurotus ostreatus), the biocontrol agent Ba...

Follicular hybrid cyst: a combination of bullous pilomatricoma and epidermoid cyst.

PubMed

Sanusi, Tutyana; Qu, Xiaoying; Li, Yanqiu; Zhang, Jing; Wang, Ming; Zhao, Yun; Yang, Zhen; An, Xiangjie; Qian, Yue; Wang, Chunsen; Chen, Hongxiang; Chen, Siyuan; Huang, Changzheng

2013-01-01

The follicular hybrid is composed of more than two components of pilosebaceous unit. There are several studies of hybrid cyst, combination of trichilemmal and epidermoid cyst was the most frequently reported. In this paper, we reported one case of hybrid cyst composed of bullous pilomatricoma and epidermoid cyst. A 14-year-old girl was complaint of a solitary flesh-colored to erythematous nodule with flaccid appearance sized 3.2 × 1.8 cm in diameter on her right upper back for one year. The histologic findings showed there were edema and proliferation of capillaries in the superficial dermis, a cyst in the middle to deep dermis. There were laminated keratins in the cystic space. The cyst wall was composed of two different components, one was composed of epithelial cells containing of granular layer, and another consisted of basophilic cells, transient cells and shadow cells. The cyst not related with Gardner's syndrome. Hybrid cyst such as trichilemmal cyst, epidermoid and pilomatricoma cysts maybe have same clinical features or mimicking each others, but we can distinguish them from histopathology evaluation.

Follicular hybrid cyst: a combination of bullous pilomatricoma and epidermoid cyst

PubMed Central

Sanusi, Tutyana; Qu, Xiaoying; Li, Yanqiu; Zhang, Jing; Wang, Ming; Zhao, Yun; Yang, Zhen; An, Xiangjie; Qian, Yue; Wang, Chunsen; Chen, Hongxiang; Chen, Siyuan; Huang, Changzheng

2013-01-01

The follicular hybrid is composed of more than two components of pilosebaceous unit. There are several studies of hybrid cyst, combination of trichilemmal and epidermoid cyst was the most frequently reported. In this paper, we reported one case of hybrid cyst composed of bullous pilomatricoma and epidermoid cyst. A 14-year-old girl was complaint of a solitary flesh-colored to erythematous nodule with flaccid appearance sized 3.2×1.8 cm in diameter on her right upper back for one year. The histologic findings showed there were edema and proliferation of capillaries in the superficial dermis, a cyst in the middle to deep dermis. There were laminated keratins in the cystic space. The cyst wall was composed of two different components, one was composed of epithelial cells containing of granular layer, and another consisted of basophilic cells, transient cells and shadow cells. The cyst not related with Gardner’s syndrome. Hybrid cyst such as trichilemmal cyst, epidermoid and pilomatricoma cysts maybe have same clinical features or mimicking each others, but we can distinguish them from histopathology evaluation. PMID:24294394

[Cystic renal neoplasms. New entities and molecular findings].

PubMed

Moch, H

2010-10-01

Renal neoplasms with dominant cysts represent a broad spectrum of known as well as novel renal tumor entities. Established renal tumors with dominant cysts include cystic nephroma, mixed epithelial and stromal tumor, synovial sarcoma and multilocular cystic renal cancer (WHO classification 2004). Novel tumor types have recently been reported, which are also characterized by marked cyst formation. Examples are tubulocystic renal cancer and renal cancer in end-stage renal disease. These tumors are very likely to be included in a future WHO classification due to their characteristic phenotype and molecular features. Cysts and clear cell renal cell carcinoma frequently coexist in the kidneys of patients with von Hippel-Lindau disease. Cysts are also a component of many sporadic clear cell renal cell carcinomas. Multilocular cystic renal cell carcinoma is composed almost exclusively of cysts and is regarded as a specific subtype of clear cell renal cancer. Recent molecular findings suggest that clear cell renal cancer may develop via a cyst-dependent mechanism in von Hippel-Lindau syndrome as well as via cyst-independent molecular pathways in sporadic clear cell renal cancer.

Comparison of Mast Cells and Inflammatory Cells within Periapical Lesions and Comparison of Degranulated Mast Cells Between Fibrous and Inflamed Area in Radicular Cysts: An Immunohistochemical Study.

PubMed

Shiromany, Aseem; Sood, Rahul; Akifuddin, Syed; Sidhu, Gagandeep Kaur; Khan, Nadia; Singla, Kapil

2014-12-01

The role of mast cells as the key effector of allergic inflammation, anaphylactic inflammatory reactions and in the pathogenesis of chronic inflammation, is well-known. The present study is adopted to compare mast cells and inflammatory cells within periapical granuloma and cysts and localize the mast cells and quantify their number in the periapical cysts so as to propose a role of mast cells in the pathogenesis of this lesion. Biopsy specimens of 30 periapical lesions were stained with hematoxylin-eosin, and immunohistochemical Mast Cell Tryptase from Bio SB (IHC detection system kit) antibody. The tryptase positive mast cells and mononuclear inflammatory cells were counted in 10 consecutive high power fields (100X) using the binocular microscope from Motic attached to a computer with Motic Advanced Images 3.2 software. Comparative microscopic analysis indicated that periapical cyst shows more percentage of mast cells and less percentage of inflammatory cell than periapical granuloma (comparison of mean and standard deviation of total number of mast cells and inflammatory cells, mast cells 3.15±1.39 in the granuloma group and 4.43±1.91in the cyst group, inflammatory cells, 67.11±1.2 in the granuloma group and 52.66±0.8 in the cyst group). Numerous degranulated mast cells were observed in the fibrous wall than the inflammatory infiltrate of the periapical cysts. The mean and standard deviation of degranulated mast cells between the inflammatory and fibrous zone within the cyst group, being 0.95±1.10 and1.68±1.34 respectively. The values varied significantly between the two zones. The number of inflammatory cells in the cyst group is less than periapical granuloma and total number of mast cells in the cyst group is more as compared to periapical granuloma. The degranulated cells were quantified and they were higher in the fibrous area of the cysts than the inflammatory zone. This study could support the fact that the various mediators released on degranulation play a role in the connective tissue remodeling, chronicity and expansion of the periapical lesion.

Expression of Ki-67 in odontogenic cysts: A comparative study between odontogenic keratocysts, radicular cysts and dentigerous cysts.

PubMed

Modi, Tapan G; Chalishazar, Monali; Kumar, Malay

2018-01-01

Odontogenic cysts are the most common cysts of the jaws and are formed from the remnants of the odontogenic apparatus. Among these odontogenic cysts, radicular cysts (RCs) (about 60% of all diagnosed jaw cysts), dentigerous cysts (DCs) (16.6% of all jaw cysts) and odontogenic keratocysts (OKCs) (11.2% of all developmental odontogenic cysts) are the most common. The behavior of any lesion is generally reflected by its growth potential. Growth potential is determined by measuring the cell proliferative activity. The cell proliferative activity is measured by various methods among which immunohistochemistry (IHC) is the commonly used technique. Most of the IHC studies on cell proliferation have been based on antibodies such as Ki-67 and proliferating cell nuclear antigen. In the present study, the total sample size comprised of 45 cases of odontogenic cysts, with 15 cases each of OKC, RC and DC. Here, an attempt is made to study immunohistochemical (streptavidin-biotin detection system HRP-DAB) method to assess the expression of Ki-67 in different layers of the epithelial lining of OKCs, RCs and DCs. Ki-67 positive cells were highest in epithelium of OKC as compared to DC and RC. The increased Ki-67 labeling index and its expression in suprabasal cell layers of epithelial lining in OKC and its correlation with suprabasal cell layers of epithelial lining in DC and RC could contribute toward its clinically aggressive behavior. OKC is of more significance to the oral pathologist and oral surgeon because of its specific histopathological features, high recurrence rate and aggressive behavior.

Renal Epithelial Cyst Formation and Enlargement in vitro: Dependence on cAMP

NASA Astrophysics Data System (ADS)

Mangoo-Karim, Roberto; Uchic, Marie; Lechene, Claude; Grantham, Jared J.

1989-08-01

Cysts, a common abnormality of kidneys, are collections of urine-like fluid enclosed by a continuous layer of epithelial cells. Renal cysts derive from nephrons and collecting ducts and progressively enlarge as a consequence of epithelial proliferation and transepithelial fluid secretion. The initiation of cyst formation and the factors that control cyst enlargement are unknown. We used an in vitro model of renal cysts to explore the role of the cAMP signal transduction system in the formation and expansion of cysts. MDCK cells, cultured in hydrated-collagen gel, produced polarized monolayered epithelial cysts when intracellular cAMP was increased by prostaglandin E1, arginine vasopressin, cholera toxin, forskolin, or 8-bromoadenosine 3',5'-cyclic monophosphate. All agonists were potentiated by 3-isobutyl-1-methylxanthine, a nucleotide phosphodiesterase inhibitor. The cell proliferation component of cyst enlargement was accelerated by cAMP agonists, as shown by the increased growth of MDCK cells in subconfluent monolayers. The fluid secretion component, reflected by the transepithelial movement of fluid across polarized monolayers of MDCK cells grown on permeable supports, was stimulated by cAMP agonists in the basolateral medium. Chloride levels were higher in the cyst fluid and the secreted fluid than in the bathing medium. We conclude that the development of MDCK cysts is dependent on cAMP. This signal transduction system may be an important modulator of epithelial cell proliferation and transepithelial fluid secretion in the kidney.

Genome Wide DNA Methylation Profiles Provide Clues to the Origin and Pathogenesis of Germ Cell Tumors

PubMed Central

Rijlaarsdam, Martin A.; Tax, David M. J.; Gillis, Ad J. M.; Dorssers, Lambert C. J.; Koestler, Devin C.; de Ridder, Jeroen; Looijenga, Leendert H. J.

2015-01-01

The cell of origin of the five subtypes (I-V) of germ cell tumors (GCTs) are assumed to be germ cells from different maturation stages. This is (potentially) reflected in their methylation status as fetal maturing primordial germ cells are globally demethylated during migration from the yolk sac to the gonad. Imprinted regions are erased in the gonad and later become uniparentally imprinted according to fetal sex. Here, 91 GCTs (type I-IV) and four cell lines were profiled (Illumina’s HumanMethylation450BeadChip). Data was pre-processed controlling for cross hybridization, SNPs, detection rate, probe-type bias and batch effects. The annotation was extended, covering snRNAs/microRNAs, repeat elements and imprinted regions. A Hidden Markov Model-based genome segmentation was devised to identify differentially methylated genomic regions. Methylation profiles allowed for separation of clusters of non-seminomas (type II), seminomas/dysgerminomas (type II), spermatocytic seminomas (type III) and teratomas/dermoid cysts (type I/IV). The seminomas, dysgerminomas and spermatocytic seminomas were globally hypomethylated, in line with previous reports and their demethylated precursor. Differential methylation and imprinting status between subtypes reflected their presumed cell of origin. Ovarian type I teratomas and dermoid cysts showed (partial) sex specific uniparental maternal imprinting. The spermatocytic seminomas showed uniparental paternal imprinting while testicular teratomas exhibited partial imprinting erasure. Somatic imprinting in type II GCTs might indicate a cell of origin after global demethylation but before imprinting erasure. This is earlier than previously described, but agrees with the totipotent/embryonic stem cell like potential of type II GCTs and their rare extra-gonadal localization. The results support the common origin of the type I teratomas and show strong similarity between ovarian type I teratomas and dermoid cysts. In conclusion, we identified specific and global methylation differences between GCT subtypes, providing insight into their developmental timing and underlying developmental biology. Data and extended annotation are deposited at GEO (GSE58538 and GPL18809). PMID:25859847

Dinoflagellate cysts and bloom events at Todos Santos Bay, Baja California, México, 1999 2000

NASA Astrophysics Data System (ADS)

Peña-Manjarrez, José Luis; Helenes, Javier; Gaxiola-Castro, Gilberto; Orellana-Cepeda, Elizabeth

2005-07-01

Forty-two species of dinoflagellate motile cells and 18 species of organic-walled dinoflagellate resting cysts were identified in samples collected at Todos Santos Bay, Baja California, México, from September 1999 to June 2000. These temperate to cool-temperate species belong mainly to the families Gonyaulacaceae and Protoperidiniaceae. Lingulodinium polyedrum (Stein, 1883) Dodge 1989 was the dominant species both in the sediments and water column. During this period we observed planktonic motile cells, temporary cysts with cellulose walls, and resting cysts with resistant dinosporin walls. Two dinoflagellate blooms occurred in the spring to summer of 2000 allowing us to observe the timing of cyst production. The temporary cysts appeared between these blooms and also in the summer, whereas the resting cysts appeared during the preceding fall and winter. Resting cysts appeared in colder conditions, whereas the temporary cysts were produced within a particular thermal window and under nutrient depletion. Resting cysts were concentrated in discrete areas at depths of less than 25 m, and associated with sediments ranging from silt to fine sand. These cysts were abundant in the surface sediments during summer, fall and winter, whereas the motile cells dominated during the spring and summer, when the two L. polyedrum blooms were observed. The abundance of cells in the plankton, comprising motile cells and temporary cysts, appears to be inversely proportional to the concentration of resting cysts of the same species in the surface sediments.

Echinococcus granulosus equinus: an ultrastructural study of murine tissue response to hydatid cysts.

PubMed

Richards, K S; Arme, C; Bridges, J F

1983-06-01

Peritoneal hydatids of Echinococcus granulosus equinus of 9 months standing in BALB/c mice occurred as free cysts or cysts within cyst masses. Both showed wide variation in size and in host tissue response, and all had a well-developed laminated layer separating the host tissue response from the germinal layer. In the smallest cyst-mass cysts the host tissue response was present as remnants of the initial cellular attack involving eosinophils. Slightly larger cyst-mass cysts possessed a primary macrophage invasion which phagocytosed the remnants of the initial attack and also, though to little effect, the laminated layer material. In the largest cyst-mass cysts a second macrophage invasion, of monocyte origin, had commenced and transformation stages of these cells to macrophages were observed. No fibroblasts surrounded individual cyst-mass cysts but they were present around the cyst mass, encapsulating it and possibly preventing further host cell invasion. Thus, the host tissue response around individual cyst-mass cysts remained 'preserved' at an early stage such as existed at the time of encapsulation. Small free cysts showed a primary macrophage invasion and transformation stages of cells of a secondary infiltration of peritoneal origin. Peripheral to the macrophages were fibroblasts demonstrating limited fibrinogenesis, and each cyst was surrounded by a layer of mesothelial cells. Large free cysts, also delimited by a mesothelial layer, possessed peripheral connective tissue, a deep fibrous layer and a monolayer of very compressed macrophages lying adjacent to the laminated layer. It is emphasized that an understanding of the host tissue response in cysts of different sizes and from different locations is an essential pre-requisite for the design of experimental studies.

Expression of Ki-67 in odontogenic cysts: A comparative study between odontogenic keratocysts, radicular cysts and dentigerous cysts

PubMed Central

Modi, Tapan G; Chalishazar, Monali; Kumar, Malay

2018-01-01

Introduction and Objectives: Odontogenic cysts are the most common cysts of the jaws and are formed from the remnants of the odontogenic apparatus. Among these odontogenic cysts, radicular cysts (RCs) (about 60% of all diagnosed jaw cysts), dentigerous cysts (DCs) (16.6% of all jaw cysts) and odontogenic keratocysts (OKCs) (11.2% of all developmental odontogenic cysts) are the most common. The behavior of any lesion is generally reflected by its growth potential. Growth potential is determined by measuring the cell proliferative activity. The cell proliferative activity is measured by various methods among which immunohistochemistry (IHC) is the commonly used technique. Most of the IHC studies on cell proliferation have been based on antibodies such as Ki-67 and proliferating cell nuclear antigen. Materials and Method: In the present study, the total sample size comprised of 45 cases of odontogenic cysts, with 15 cases each of OKC, RC and DC. Here, an attempt is made to study immunohistochemical (streptavidin-biotin detection system HRP-DAB) method to assess the expression of Ki-67 in different layers of the epithelial lining of OKCs, RCs and DCs. Observations and Results: Ki-67 positive cells were highest in epithelium of OKC as compared to DC and RC. Conclusion: The increased Ki-67 labeling index and its expression in suprabasal cell layers of epithelial lining in OKC and its correlation with suprabasal cell layers of epithelial lining in DC and RC could contribute toward its clinically aggressive behavior. OKC is of more significance to the oral pathologist and oral surgeon because of its specific histopathological features, high recurrence rate and aggressive behavior. PMID:29731577

Environmental pollution and acne: Chloracne

PubMed Central

Zouboulis, Christos C; Xia, Longqing

2009-01-01

Environmental pollutants can result in a variant of acne called ‘chloracne’. Chloracne is caused by systemic exposure to certain halogenated aromatic hydrocarbons ‘chloracnegens’, and is considered to be one of the most sensitive indicators of systemic poisoning by these compounds. Dioxin is the most potent environmental chloracnegen. Most cases of chloracne have resulted from occupational and non-occupational exposures, non-occupational chloracne mainly resulted from contaminated industrial wastes and contaminated food products. Non-inflammatory comedones and straw-colored cysts are the primary clinical manifestation of chloracne. Increasing of cysts in number is a signal of aggravation of chloracne. Generalized lesions can appear on the face, neck, trunk, exterimities, genitalia, axillary and other areas. Course of chloracne is chronic. Severity of chloracne is related to dosage of exposed chloracnegens, chloracnegenic potency and individual susceptibility. Histopathology of chloracne is characterized mainly by hyperplasia of epidermal cell, while follicular and sebaceous gland are taken placed by keratinized epidermal cell. The pathogenesis of chloracne maybe related to the imbalance of epidermal stem cell. Chloracne appears to be resistant to all tested forms of treatment. The only way to control chloracne is to prevent exposure to chloracnegens. PMID:20436879

Lineage-negative Progenitors Mobilize to Regenerate Lung Epithelium after Major Injury

PubMed Central

Vaughan, Andrew E.; Brumwell, Alexis N.; Xi, Ying; Gotts, Jeffrey; Brownfield, Doug G.; Treutlein, Barbara; Tan, Kevin; Tan, Victor; Liu, Fengchun; Looney, Mark R.; Matthay, Michael; Rock, Jason R.; Chapman, Harold A.

2014-01-01

Broadly, tissue regeneration is achieved in two ways: by proliferation of common differentiated cells and/or by deployment of specialized stem/progenitor cells. Which of these pathways applies is both organ and injury-specific1–4. Current paradigms in the lung posit that epithelial repair can be attributed to cells expressing mature lineage markers5–8. In contrast we here define the regenerative role of previously uncharacterized, rare lineage-negative epithelial stem/progenitor (LNEPs) cells present within normal distal lung. Quiescent LNEPs activate a ΔNp63/cytokeratin 5 (Krt5+) remodeling program after influenza or bleomycin injury. Activated cells proliferate and migrate widely to occupy heavily injured areas depleted of mature lineages, whereupon they differentiate toward mature epithelium. Lineage tracing revealed scant contribution of pre-existing mature epithelial cells in such repair, whereas orthotopic transplantation of LNEPs, isolated by a definitive surface profile identified through single cell sequencing, directly demonstrated the proliferative capacity and multipotency of this population. LNEPs require Notch signaling to activate the ΔNp63/Krt5+ program whereas subsequent Notch blockade promotes an alveolar cell fate. Persistent Notch signaling post-injury led to parenchymal micro-honeycombing, indicative of failed regeneration. Lungs from fibrosis patients show analogous honeycomb cysts with evidence of hyperactive Notch signaling. Our findings indicate distinct stem/progenitor cell pools repopulate injured tissue depending on the extent of injury, and the outcomes of regeneration or fibrosis may ride in part on the dynamics of LNEP Notch signaling. PMID:25533958

Comparison of Mast Cells and Inflammatory Cells within Periapical Lesions and Comparison of Degranulated Mast Cells Between Fibrous and Inflamed Area in Radicular Cysts: An Immunohistochemical Study

PubMed Central

Sood, Rahul; Akifuddin, Syed; Sidhu, Gagandeep Kaur; Khan, Nadia; Singla, Kapil

2014-01-01

Objective: The role of mast cells as the key effector of allergic inflammation, anaphylactic inflammatory reactions and in the pathogenesis of chronic inflammation, is well-known. The present study is adopted to compare mast cells and inflammatory cells within periapical granuloma and cysts and localize the mast cells and quantify their number in the periapical cysts so as to propose a role of mast cells in the pathogenesis of this lesion. Materials and Methods: Biopsy specimens of 30 periapical lesions were stained with hematoxylin–eosin, and immunohistochemical Mast Cell Tryptase from Bio SB (IHC detection system kit) antibody. The tryptase positive mast cells and mononuclear inflammatory cells were counted in 10 consecutive high power fields (100X) using the binocular microscope from Motic attached to a computer with Motic Advanced Images 3.2 software. Results: Comparative microscopic analysis indicated that periapical cyst shows more percentage of mast cells and less percentage of inflammatory cell than periapical granuloma (comparison of mean and standard deviation of total number of mast cells and inflammatory cells, mast cells 3.15±1.39 in the granuloma group and 4.43±1.91in the cyst group, inflammatory cells, 67.11±1.2 in the granuloma group and 52.66±0.8 in the cyst group). Numerous degranulated mast cells were observed in the fibrous wall than the inflammatory infiltrate of the periapical cysts. The mean and standard deviation of degranulated mast cells between the inflammatory and fibrous zone within the cyst group, being 0.95±1.10 and1.68±1.34 respectively. The values varied significantly between the two zones. Conclusion: The number of inflammatory cells in the cyst group is less than periapical granuloma and total number of mast cells in the cyst group is more as compared to periapical granuloma. The degranulated cells were quantified and they were higher in the fibrous area of the cysts than the inflammatory zone. This study could support the fact that the various mediators released on degranulation play a role in the connective tissue remodeling, chronicity and expansion of the periapical lesion. PMID:25654034

Cystic renal tumors: new entities and novel concepts.

PubMed

Moch, Holger

2010-05-01

Cystic renal neoplasms and renal epithelial stromal tumors are diagnostically challenging and represent some novel tumor entities. In this article, clinical and pathologic features of established and novel entities are discussed. Predominantly cystic renal tumors include cystic nephroma/mixed epithelial and stromal tumor, synovial sarcoma, and multilocular cystic renal cell carcinoma. These entities are own tumor entities of the 2004 WHO classification of renal tumors. Tubulocystic carcinoma and acquired cystic disease-associated renal cell carcinoma are neoplasms with an intrinsically cystic growth pattern. Both tumor types should be included in a future WHO classification as novel entities owing to their characteristic features. Cysts and clear cell renal cell carcinoma frequently coexist within the kidneys of patients with von Hippel-Lindau disease. Sporadic clear cell renal cell carcinomas often contain cysts, usually as a minor component. Some clear cell renal cell carcinomas have prominent cysts, and multilocular cystic renal cell carcinoma is composed almost exclusively of cysts. Recent molecular findings suggest that clear cell renal cancer may develop through cyst-dependent and cyst-independent molecular pathways.

Location on chitin in the cyst wall of Entamoeba invadens with colloidal gold tracers.

PubMed

Arroyo-Begovich, A; Cárabez-Trejo, A

1982-04-01

Chitin was located in the cyst wall of Entamoeba invadens with colloidal gold-linked wheat germ agglutinin. Cysts stained differentially from trophozoites when encysting cultures were treated with the gold tracer; cysts acquired a wine-red coloration while, in general trophozoites remained unstained. Observation of cells with the electron microscope revealed that the tracer particles were bound specifically to the walls of the surface of the cyst when cells were exposed in suspension, and to the cyst wall cross-section, when cells were exposed to the tracer in thin section, indicating that chitin fibers were distributed on the surface as well as throughout the matrix of the cyst wall.

Enhanced resistance to soybean cyst nematode Heterodera glycines in transgenic soybean by silencing putative CLE receptors.

PubMed

Guo, Xiaoli; Chronis, Demosthenis; De La Torre, Carola M; Smeda, John; Wang, Xiaohong; Mitchum, Melissa G

2015-08-01

CLE peptides are small extracellular proteins important in regulating plant meristematic activity through the CLE-receptor kinase-WOX signalling module. Stem cell pools in the SAM (shoot apical meristem), RAM (root apical meristem) and vascular cambium are controlled by CLE signalling pathways. Interestingly, plant-parasitic cyst nematodes secrete CLE-like effector proteins, which act as ligand mimics of plant CLE peptides and are required for successful parasitism. Recently, we demonstrated that Arabidopsis CLE receptors CLAVATA1 (CLV1), the CLAVATA2 (CLV2)/CORYNE (CRN) heterodimer receptor complex and RECEPTOR-LIKE PROTEIN KINASE 2 (RPK2), which transmit the CLV3 signal in the SAM, are required for perception of beet cyst nematode Heterodera schachtii CLEs. Reduction in nematode infection was observed in clv1, clv2, crn, rpk2 and combined double and triple mutants. In an effort to develop nematode resistance in an agriculturally important crop, orthologues of Arabidopsis receptors including CLV1, CLV2, CRN and RPK2 were identified from soybean, a host for the soybean cyst nematode Heterodera glycines. For each of the receptors, there are at least two paralogues in the soybean genome. Localization studies showed that most receptors are expressed in the root, but vary in their level of expression and spatial expression patterns. Expression in nematode-induced feeding cells was also confirmed. In vitro direct binding of the soybean receptors with the HgCLE peptide was analysed. Knock-down of the receptors in soybean hairy roots showed enhanced resistance to SCN. Our findings suggest that targeted disruption of nematode CLE signalling may be a potential means to engineer nematode resistance in crop plants. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Evaluation of mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors.

PubMed

de Noronha Santos Netto, Juliana; Pires, Fábio Ramôa; da Fonseca, Eliene Carvalho; Silva, Licínio Esmeraldo; de Queiroz Chaves Lourenço, Simone

2012-09-01

Several cell types are associated with the development of cystic and tumoral odontogenic lesions. Among inflammatory cells, mast cells can be associated with their pathogenesis. The aim of this study was to analyze mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors. Tissue sections were submitted to toluidine blue staining and immunohistochemistry with antibody anti-tryptase (clone G3). Mast cells were quantitated using Image-Pro Plus software to obtain the mean number of mast cells in three regions: epithelial, superficial portion of the fibrous wall and deep portion of the fibrous wall from 20 periapical cysts, 20 dentigerous cysts (six non-inflamed and 14 inflamed) and 20 keratocystic odontogenic tumors (four non-inflamed and 16 inflamed). The mean number of mast cells detected per lesion by immunohistochemistry (4.1) was higher than by histochemistry (1.5) (P<0.0001). Inflamed dentigerous cysts and keratocystic odontogenic tumors showed a higher mean number of mast cells than non-inflamed lesions in all regions. The deep region from all cysts showed the highest mean number of degranulated mast cells, except for non-inflamed keratocystic odontogenic tumors analyzed by immunohistochemistry. Immunohistochemical staining detected higher number of mast cells than histochemistry. The higher number of mast cells observed in inflamed lesions could indicate the participation of these cells in the inflammatory response in odontogenic lesions. The prevalence of degranulated mast cells in the deep region suggests intense activity of these cells, possibly related to growth of cystic lesions. © 2012 John Wiley & Sons A/S.

Coexistence of mucous retention cyst and basal cell adenoma arising from the lining epithelium of the cyst. Report of two cases.

PubMed

Antoniades, D; Epivatianos, A; Markopoulos, A; Kolokotronis, A; Zaraboukas, T

2009-01-01

To report 2 cases of coexisting mucous retention cyst and basal cell adenoma arising from the lining epithelium of the cyst. Two cases of painless swellings, well-demarcated, soft to palpation, and located in the submucosa of the upper lip were clinically examined with the provisional diagnosis of mucocele or salivary gland tumor. Histological examination showed the presence of a large unilocular cystic cavity in many parts surrounded by single or bilayered lining epithelium composed of flattened to cuboidal cells, and in other parts surrounded by projections of cells arranged in a trabecular pattern far into the cystic cavity. The trabeculae were composed of basal and low columnar cells that sometimes formed small duct-like structures. Immunohistochemistry showed that the lining epithelium of the cystic cavity and the cells of the projections expressed cytokeratin 7 and high-molecular-weight cytokeratins. The cells of the projections were weakly positive for S-100 protein and negative for vimentin and alpha-smooth muscle actin. Based on the results, a diagnosis of coexisting mucous retention cysts and basal cell adenomas arising from the lining epithelium of cysts was made. The coexistence of mucous retention cysts and basal cell adenomas arising from the lining epithelium of the cyst is reported. Copyright 2009 S. Karger AG, Basel.

Host Th1/Th2 immune response to Taenia solium cyst antigens in relation to cyst burden of neurocysticercosis.

PubMed

Tharmalingam, J; Prabhakar, A T; Gangadaran, P; Dorny, P; Vercruysse, J; Geldhof, P; Rajshekhar, V; Alexander, M; Oommen, A

2016-10-01

Neurocysticercosis (NCC), Taenia solium larval infection of the brain, is an important cause of acquired seizures in endemic countries, which relate to number, location and degenerating cysts in the brain. Multicyst infections are common in endemic countries although single-cyst infection prevails in India. Single-cyst infections in an endemic country suggest a role for host immunity limiting the infection. This study examined ex vivo CD4(+) T cells and in vitro Th1 and Th2 cytokine responses to T. solium cyst antigens of peripheral blood mononuclear cells of healthy subjects from endemic and nonendemic regions and of single- and multicyst-infected patients for association with cyst burden of NCC. T. solium cyst antigens elicited a Th1 cytokine response in healthy subjects of T. solium-endemic and T. solium-non-endemic regions and those with single-cyst infections and a Th2 cytokine response from subjects with multicyst neurocysticercosis. Multicyst neurocysticercosis subjects also exhibited low levels of effector memory CD4(+) T cells. Th1 cytokine response of T. solium exposure and low infectious loads may aid in limiting cyst number. Th2 cytokines and low effector T cells may enable multiple-cyst infections to establish and persist. © 2016 John Wiley & Sons Ltd.

Expression of cytokeratins in odontogenic jaw cysts: monoclonal antibodies reveal distinct variation between different cyst types.

PubMed

Hormia, M; Ylipaavalniemi, P; Nagle, R B; Virtanen, I

1987-08-01

Immunostaining with monoclonal antibodies was used to study and compare the cytokeratin content of odontogenic cysts and normal gingival epithelium. Two monoclonal antibodies, PKK2 and KA1, stained the whole epithelium in all cyst samples. In gingiva, PKK2 gave a suprabasal staining and KA1 reacted with all epithelial cell layers. Antibodies PKK1, KM 4.62 and KS 8.12 gave a heterogeneous staining in follicular and radicular cysts. In keratocysts and in gingiva PKK1 and KM 4.62 reacted mainly with basal cells and KS 8.12 gave a suprabasal staining. Antibodies reacting with the simple epithelial cytokeratin polypeptide No. 18 (PKK3, KS 18.18) recognized in gingiva only solitary cells compatible with Merkel cells. In a case of follicular ameloblastoma a distinct staining of tumor epithelium was revealed with these antibodies. In 2 follicular cysts, but not in other cyst types, a layer of cytokeratin 18-positive cells was revealed. KA5 and KK 8.60 antibodies, reacting exclusively with keratinizing epithelia, including normal gingiva, gave no reaction in radicular cysts, keratocysts and ameloblastoma. Two of the follicular cysts, were negative for PKK3 and KS 18.18, but reacted strongly with KA5 and KK 8.60. The present results show that odontogenic jaw cysts have distinct differences in their cytokeratin content. With the exception of some follicular cysts, they lack signs of keratinizing epithelial differentiation. Only follicular cysts appear to share with some types of ameloblastoma the expression of cytokeratin polypeptide No. 18.

Fluorescence diagnosis of tumor cells in hemangioblastoma cysts with 5-aminolevulinic acid.

PubMed

Utsuki, Satoshi; Oka, Hidehiro; Sato, Kimitoshi; Shimizu, Satoru; Suzuki, Sachio; Fujii, Kiyotaka

2010-01-01

Peritumoral hemangioblastoma cysts are usually composed of fibrous tissue without tumor cells. The authors describe the first case in which fluorescence with 5-aminolevulinic acid (5-ALA) was used to diagnose a hemangioblastoma tumor in a peritumoral cyst wall. A 27-year-old woman with a homogeneous, enhanced nodular lesion in the right hemisphere of the cerebellum underwent surgical treatment. After the nodular lesion was removed, the cyst region was observed with the aid of a semiconductor laser with a peak wavelength of 405 +/- 1 nm, which was powered using a fiberoptic cable. The cyst region was visualized with strong fluorescence, which disappeared after tissue removal. The fluorescent cyst consisted of tumor cells. The authors conclude that fluorescence diagnosis performed using 5-ALA can inform the choice of removing hemangioblastoma cysts.

Notch 1 Receptor, Delta 1 Ligand and HES 1 Transcription Factor are Expressed in the Lining Epithelium of Periapical Cysts (Preliminary Study).

PubMed

Meliou, E; Kerezoudis, Np; Tosios, Ki; Kiaris, H

2010-07-27

Periapical cyst is a chronic inflammatory disorder of periradicular tissues. The precise pathological mechanisms involved in periapical cyst enlargement remain unclear. Notch signaling is an evolutionarily conserved pathway with a regulatory role in cell fate decisions during development and in carcinogenesis. To date, there are no published data available on the expression of Notch signaling components in periapical cysts or any other jaw cyst. In this immunohistochemical study we have examined the expression of the receptor Notch 1, the ligand Delta 1 and the transcription factor HES 1 in the epithelium of well defined periapical cysts. Immunostaining reaction of Notch 1, Delta 1 and HES 1 was observed in the cytoplasm and/or the cytoplasmic membrane and occasionally in the nucleus in the majority of epithelial cells of all periapical cysts. The present observations indicate that Notch pathway is active in the epithelium of periapical cysts. It can be speculated that activation of epithelial cells of periapical cysts is associated with activation of Notch pathway and imply involvement of this pathway in periapical cyst growth and expansion.

Distribution of mast cells and macrophages and expression of interleukin-6 in periapical cysts.

PubMed

Bracks, Igor Vieira; Armada, Luciana; Gonçalves, Lúcio Souza; Pires, Fábio Ramôa

2014-01-01

Mast cells and macrophages are important components of the inflammatory infiltrate found in inflammatory periapical diseases. Several cytokines participate in the mechanisms of inflammation, tissue repair, and bone resorption associated with periapical cysts. The aim of the present study was to evaluate the distribution of mast cells and macrophages and the expression of interleukin-6 (IL-6) in periapical cysts. Thirty periapical cysts were selected for the study, and clinical, demographic, and gross information from the cases was obtained from the laboratory records. Five-micrometer sections stained with hematoxylin-eosin were reviewed for analysis of the microscopic features of the cysts, and 3-μm sections on silanized slides were used for immunohistochemical reactions with anti-tryptase, anti-CD68, and anti-IL-6. There was no statistically significant difference in the mean number of mast cells and macrophages when comparing superficial and deep regions of the fibrous capsule of the cysts. Mean number of mast cells on the superficial region of the fibrous capsule was higher in cysts showing intense superficial inflammation and exocytosis. Macrophages were more commonly found in areas showing IL-6 expression, and IL-6 was less expressed in deep regions of the fibrous capsule in cysts showing greater gross volume. The results reinforced the participation of mast cells and macrophages in the pathogenesis of periapical cysts and suggested that IL-6 is not the major bone resorption mediator in larger periapical cysts. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Stress Management in Cyst-Forming Free-Living Protists: Programmed Cell Death and/or Encystment

PubMed Central

Khan, Naveed Ahmed; Iqbal, Junaid

2015-01-01

In the face of harsh conditions and given a choice, a cell may (i) undergo programmed cell death, (ii) transform into a cancer cell, or (iii) enclose itself into a cyst form. In metazoans, the available evidence suggests that cellular machinery exists only to execute or avoid programmed cell death, while the ability to form a cyst was either lost or never developed. For cyst-forming free-living protists, here we pose the question whether the ability to encyst was gained at the expense of the programmed cell death or both functions coexist to counter unfavorable environmental conditions with mutually exclusive phenotypes. PMID:25648302

Notch 1 Receptor, Delta 1 Ligand and HES 1 Transcription Factor are Expressed in the Lining Epithelium of Periapical Cysts (Preliminary Study)

PubMed Central

Meliou, E; Kerezoudis, NP; Tosios, KI; Kiaris, H

2010-01-01

Periapical cyst is a chronic inflammatory disorder of periradicular tissues. The precise pathological mechanisms involved in periapical cyst enlargement remain unclear. Notch signaling is an evolutionarily conserved pathway with a regulatory role in cell fate decisions during development and in carcinogenesis. To date, there are no published data available on the expression of Notch signaling components in periapical cysts or any other jaw cyst. In this immunohistochemical study we have examined the expression of the receptor Notch 1, the ligand Delta 1 and the transcription factor HES 1 in the epithelium of well defined periapical cysts. Immunostaining reaction of Notch 1, Delta 1 and HES 1 was observed in the cytoplasm and/or the cytoplasmic membrane and occasionally in the nucleus in the majority of epithelial cells of all periapical cysts. The present observations indicate that Notch pathway is active in the epithelium of periapical cysts. It can be speculated that activation of epithelial cells of periapical cysts is associated with activation of Notch pathway and imply involvement of this pathway in periapical cyst growth and expansion. PMID:21116324

Receptor activator NFkappaB-ligand and osteoprotegerin protein expression in human periapical cysts and granulomas.

PubMed

Menezes, Renato; Bramante, Clóvis Monteiro; da Silva Paiva, Katiúcia Batista; Letra, Ariadne; Carneiro, Everdan; Fernando Zambuzzi, Willian; Granjeiro, José Mauro

2006-09-01

The purpose of this study was to determine the expression of receptor activator of NFkappaB ligand (RANKL) and osteoprotegerin (OPG) associated with bone destruction in periapical cysts and granulomas. Forty human dental chronic periapical lesions were collected after periapical surgery. The lesions collected were fixed in 10% buffered formalin and histologically processed. At least 2 sections of each specimen were stained with hematoxylin and eosin for microscopic diagnosis. After that, 10 human periapical granulomas and 10 cysts were selected for immunohistochemical analysis for RANKL, OPG, and CD68+. Polymorphonuclear neutrophils, macrophages, endothelial cells, and lymphocytes were stained for RANKL and OPG in both lesions. Epithelial cells were also stained for RANKL and OPG in periapical cysts. Quantitative analysis was conducted and the results were expressed as a ratio of the number of immunostained cells over the total number of cells in the field (n = 100). The ratio of RANKL+/total cells was higher than OPG+/total cells in periapical granulomas (0.553 +/- 0.153 and 0.483 +/- 0.189, respectively; P < .0012; paired t test) and in cysts (0.519 +/- 0.09 and 0.339 +/- 0.117, respectively; P < .0001; paired t test). The ratios of OPG+/total cells (P < .0001; paired t test) and RANKL+/total cells (P < .0322; paired t test) were greater in granulomas than in cysts. However, the ratio RANKL+/OPG+ in granulomas (1.336 +/- 0.723) and cysts (1.404 +/- 0.385) was not significantly different. The ratio of CD68+/total cells was significantly higher in granulomas (0.381 +/- 0.040) than in cysts (0.307 +/- 0.068) (P < .0001; unpaired t test with Welch correction). Taking into account the limitations of the experimental approach employed, our findings indicate the presence of RANKL and OPG in cysts and granulomas, strongly suggesting the involvement of these gene products in the development of periapical lesions.

An Improved Quantitative Real-Time PCR Assay for the Enumeration of Heterosigma akashiwo (Raphidophyceae) Cysts Using a DNA Debris Removal Method and a Cyst-Based Standard Curve.

PubMed

Kim, Joo-Hwan; Kim, Jin Ho; Wang, Pengbin; Park, Bum Soo; Han, Myung-Soo

2016-01-01

The identification and quantification of Heterosigma akashiwo cysts in sediments by light microscopy can be difficult due to the small size and morphology of the cysts, which are often indistinguishable from those of other types of algae. Quantitative real-time PCR (qPCR) based assays represent a potentially efficient method for quantifying the abundance of H. akashiwo cysts, although standard curves must be based on cyst DNA rather than on vegetative cell DNA due to differences in gene copy number and DNA extraction yield between these two cell types. Furthermore, qPCR on sediment samples can be complicated by the presence of extracellular DNA debris. To solve these problems, we constructed a cyst-based standard curve and developed a simple method for removing DNA debris from sediment samples. This cyst-based standard curve was compared with a standard curve based on vegetative cells, as vegetative cells may have twice the gene copy number of cysts. To remove DNA debris from the sediment, we developed a simple method involving dilution with distilled water and heating at 75°C. A total of 18 sediment samples were used to evaluate this method. Cyst abundance determined using the qPCR assay without DNA debris removal yielded results up to 51-fold greater than with direct counting. By contrast, a highly significant correlation was observed between cyst abundance determined by direct counting and the qPCR assay in conjunction with DNA debris removal (r2 = 0.72, slope = 1.07, p < 0.001). Therefore, this improved qPCR method should be a powerful tool for the accurate quantification of H. akashiwo cysts in sediment samples.

Multiplexed Immunofluorescence Reveals Potential PD-1/PD-L1 Pathway Vulnerabilities in Craniopharyngioma.

PubMed

Coy, Shannon; Rashid, Rumana; Lin, Jia-Ren; Du, Ziming; Donson, Andrew M; Hankinson, Todd C; Foreman, Nicholas K; Manley, Peter E; Kieran, Mark W; Reardon, David A; Sorger, Peter K; Santagata, Sandro

2018-03-02

Craniopharyngiomas are neoplasms of the sellar/parasellar region that are classified into adamantinomatous (ACP) and papillary (PCP) subtypes. Surgical resection of craniopharyngiomas is challenging, and recurrence is common, frequently leading to profound morbidity. BRAF V600E mutations render PCP susceptible to BRAF/MEK inhibitors, but effective targeted therapies are needed for ACP. We explored the feasibility of targeting the PD-1/PD-L1 immune checkpoint pathway in ACP and PCP. We mapped and quantified PD-L1 and PD-1 expression in ACP and PCP resections using immunohistochemistry, immunofluorescence, and RNA in situ hybridization. We used tissue-based cyclic immunofluorescence (t-CyCIF) to map the spatial distribution of immune cells and characterize cell cycle and signaling pathways in ACP tumor cells which intrinsically express PD-1. All ACP (15±14% of cells, n=23, average±S.D.) and PCP (35±22% of cells, n=18) resections expressed PD-L1. In ACP, PD-L1 was predominantly expressed by tumor cells comprising the cyst-lining. In PCP, PD-L1 was highly-expressed by tumor cells surrounding the stromal fibrovascular cores. ACP also exhibited tumor cell-intrinsic PD-1 expression in whorled epithelial cells with nuclear-localized beta-catenin. These cells exhibited evidence of elevated mTOR and MAPK signaling. Profiling of immune populations in ACP and PCP showed a modest density of CD8+ T-cells. ACP exhibit PD-L1 expression in the tumor cyst-lining and intrinsic PD-1 expression in cells proposed to comprise an oncogenic stem-like population. In PCP, proliferative tumor cells express PD-L1 in a continuous band at the stromal-epithelial interface. Targeting PD-L1 and/or PD-1 in both subtypes of craniopharyngioma might therefore be an effective therapeutic strategy.

Expression of Nek1 during kidney development and cyst formation in multiple nephron segments in the Nek1-deficient kat2J mouse model of polycystic kidney disease.

PubMed

Chen, Yumay; Chiang, Huai-Chin; Litchfield, Patricia; Pena, Michelle; Juang, Charity; Riley, Daniel J

2014-07-17

Neks, mammalian orthologs of the fungal protein kinase never-in-mitosis A, have been implicated in the pathogenesis of polycystic kidney disease. Among them, Nek1 is the primary protein inactivated in kat2J mouse models of PKD. We report the expression pattern of Nek1 and characterize the renal cysts that develop in kat2J mice. Nek1 is detectable in all murine tissues but its expression in wild type and kat2J heterozygous kidneys decrease as the kidneys mature, especially in tubular epithelial cells. In the embryonic kidney, Nek1 expression is most prominent in cells that will become podocytes and proximal tubules. Kidney development in kat2J homozygous mice is aberrant early, before the appearance of gross cysts: developing cortical zones are thin, populated by immature glomeruli, and characterized by excessive apoptosis of several cell types. Cysts in kat2J homozygous mice form postnatally in Bowman's space as well as different tubular subtypes. Late in life, kat2J heterozygous mice form renal cysts and the cells lining these cysts lack staining for Nek1. The primary cilia of cells lining cysts in kat2J homozygous mice are morphologically diverse: in some cells they are unusually long and in others there are multiple cilia of varying lengths. Our studies indicate that Nek1 deficiency leads to disordered kidney maturation, and cysts throughout the nephron.

Neurenteric Cyst or Neuroendodermal Cyst? Immunohistochemical Study and Pathogenesis.

PubMed

Chen, Chun-Ting; Lai, Hung-Yi; Jung, Shih-Ming; Lee, Ching-Yi; Wu, Chieh-Tsai; Lee, Shih-Tseng

2016-12-01

Neurenteric cysts are rare central nervous system lesions derived from an endodermal origin. There is no consensus concerning pathogenesis because of the paucity of occurrences. We report an immunohistochemical study of 10 cases with neurenteric cysts and postulate its pathogenesis. Ten patients underwent surgical treatment for neurenteric cysts from 1995 to 2015. We retrospectively reviewed clinical, radiologic, operative, and pathologic findings for these patients. Immunohistochemical stains were completed in all cases to distinguish cell type and origin. Three cell types were identified: pseudostratified-ciliated, goblet-columnar, and simple cuboidal cells. All cases were positive for cytokeratin 7, and negative for cytokeratin 20, caudal-type homeobox 2, mucin 2, thyroid transcription factor 1, human chorionic gonadotropin, placental alkaline phosphatase, and cluster of differentiation 31. Four of them had positive staining for mucin 5AC, with expression only in goblet-columnar cells. According to the immunohistochemical results, the cells resembled the respiratory tract (pseudostratified-ciliated), stomach (goblet-columnar), and respiratory bronchioles (simple cuboidal). Seventy-five percent of cases with recurrence had a goblet-columnar component, emphasizing the importance of total resection of the cyst and complete pathologic examination. We postulate that the cystic tumor was derived from multipotent endodermal cells that migrated and traveled along the neuroectoderm, with incomplete differentiation into various cell types as a result of an unsuitable microenvironment. Because the neurenteric canal was only the channel of migration rather than a component of the cysts, the term neuroendodermal cysts is more precise in presenting the embryopathogenesis. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Intratarsal keratinous eyelid cysts in Gorlin syndrome: A review and reappraisal.

PubMed

Wolkow, Natalie; Jakobiec, Frederick A; Yoon, Michael K

2017-12-27

A 38-year-old woman presented with multiple bilateral recurrent eyelid cysts. Her medical history was notable for Gorlin (nevoid basal cell carcinoma) syndrome. Histopathologic and immunohistochemical examinations revealed that the lesions were intratarsal keratinous cysts. They were similar in appearance to sporadic intratarsal keratinous cysts and closely resembled odontogenic keratocysts of the jaw. Eyelid cysts occur in up to 40% of patients with Gorlin syndrome; however, their description has been cursory and, for the most part, outside of the ophthalmic literature. Although ophthalmologists are familiar with the periocular basal cell carcinomas that occur in patients with Gorlin syndrome, up to 10% of patients never develop a basal cell carcinoma, but they may manifest other ophthalmic findings. Awareness of these other features may contribute to the earlier diagnosis of the syndrome. We discuss the clinical and histopathologic features of intratarsal keratinous cysts in Gorlin syndrome, comparing them to sporadic intratarsal keratinous cysts, other eyelid cysts, and jaw cysts that also characterize this syndrome. We briefly review the ocular and systemic manifestations of Gorlin syndrome and recent genetic and therapeutic developments so that the eyelid cysts may be appreciated within the appropriate context of Gorlin syndrome as a whole. Copyright © 2017 Elsevier Inc. All rights reserved.

Foetal hepatic progenitor cells assume a cholangiocytic cell phenotype during two-dimensional pre-culture.

PubMed

Anzai, Kazuya; Chikada, Hiromi; Tsuruya, Kota; Ida, Kinuyo; Kagawa, Tatehiro; Inagaki, Yutaka; Mine, Tesuya; Kamiya, Akihide

2016-06-23

Liver consists of parenchymal hepatocytes and other cells. Liver progenitor cell (LPC) is the origin of both hepatocytes and cholangiocytic cells. The analyses of mechanism regulating differentiation of LPCs into these functional cells are important for liver regenerative therapy using progenitor cells. LPCs in adult livers were found to form cysts with cholangiocytic characteristics in 3D culture. In contrast, foetal LPCs cannot form these cholangiocytic cysts in the same culture. Thus, the transition of foetal LPCs into cholangiocytic progenitor cells might occur during liver development. Primary CD45(-)Ter119(-)Dlk1(+) LPCs derived from murine foetal livers formed ALBUMIN (ALB)(+)CYTOKERATIN (CK)19(-) non-cholangiocytic cysts within 3D culture. In contrast, when foetal LPCs were pre-cultured on gelatine-coated dishes, they formed ALB(-)CK19(+) cholangiocytic cysts. When hepatocyte growth factor or oncostatin M, which are inducers of hepatocytic differentiation, was added to pre-culture, LPCs did not form cholangiocytic cysts. These results suggest that the pre-culture on gelatine-coated dishes changed the characteristics of foetal LPCs into cholangiocytic cells. Furthermore, neonatal liver progenitor cells were able to form cholangiocytic cysts in 3D culture without pre-culture. It is therefore possible that the pre-culture of mid-foetal LPCs in vitro functioned as a substitute for the late-foetal maturation step in vivo.

Autocrine IL-10 activation of the STAT3 pathway is required for pathological macrophage differentiation in polycystic kidney disease

PubMed Central

Peda, Jacqueline D.; Salah, Sally M.; Wallace, Darren P.; Fields, Patrick E.; Grantham, Connor J.; Fields, Timothy A.

2016-01-01

ABSTRACT Polycystic kidney disease (PKD) is characterized by slow expansion of fluid-filled cysts derived from tubules within the kidney. Cystic expansion results in injury to surrounding parenchyma and leads to inflammation, scarring and ultimately loss of renal function. Macrophages are a key element in this process, promoting cyst epithelial cell proliferation, cyst expansion and disease progression. Previously, we have shown that the microenvironment established by cystic epithelial cells can ‘program’ macrophages, inducing M2-like macrophage polarization that is characterized by expression of markers that include Arg1 and Il10. Here, we functionally characterize these macrophages, demonstrating that their differentiation enhances their ability to promote cyst cell proliferation. This observation indicates a model of reciprocal pathological interactions between cysts and the innate immune system: cyst epithelial cells promote macrophage polarization to a phenotype that, in turn, is especially efficient in promoting cyst cell proliferation and cyst growth. To better understand the genesis of this macrophage phenotype, we examined the role of IL-10, a regulatory cytokine shown to be important for macrophage-stimulated tissue repair in other settings. Herein, we show that the acquisition of the pathological macrophage phenotype requires IL-10 secretion by the macrophages. Further, we demonstrate a requirement for IL-10-dependent autocrine activation of the STAT3 pathway. These data suggest that the IL-10 pathway in macrophages plays an essential role in the pathological relationship between cysts and the innate immune system in PKD, and thus could be a potential therapeutic target. PMID:27491076

Expression of extracellular matrix metalloproteinase inducer in odontogenic cysts.

PubMed

Ali, Mohammad Abdulhadi Abbas

2008-08-01

Extracellular matrix metalloproteinase inducer (EMMPRIN) is known to induce matrix metalloproteinase (MMP) production. The expression of EMMPRIN in odontogenic cysts has not been previously studied. This study was done to determine the presence and the variability of EMMPRIN expression in various types of odontogenic cysts. An immunohistochemical study using a polyclonal anti-EMMPRIN antibody was done using 48 odontogenic cyst cases: 13 odontogenic keratocysts (OKCs), 18 dentigerous cysts (DCs), and 17 periapical cysts (PAs). Twelve cases of normal dental follicles (DFs) were also included in this study for comparison. EMMPRIN immunoreactivity was detected in all of the cysts and DFs studied. In odontogenic cysts, EMMPRIN immunoreactivity was generally higher in basal cells than in suprabasal cells. The overall EMMPRIN expression in the epithelial lining of the 3 different types of odontogenic cyst was significantly higher than in the DFs. Overall EMMPRIN expression was also found to be significantly higher in the epithelial lining of OKCs than in the other types of cysts. This study confirmed that EMMPRIN is present in odontogenic cysts and DFs. The higher EMMPRIN expression in OKCs suggests that it may be involved in the aggressive behavior of this type of cyst.

Complete in vitro oogenesis: retrospects and prospects.

PubMed

Wang, Jun-Jie; Ge, Wei; Liu, Jing-Cai; Klinger, Francesca Gioia; Dyce, Paul W; De Felici, Massimo; Shen, Wei

2017-11-01

Precise control of mammalian oogenesis has been a traditional focus of reproductive and developmental biology research. Recently, new reports have introduced the possibility of obtaining functional gametes derived in vitro from stem cells. The potential to produce functional gametes from stem cells has exciting applications for regenerative medicine though still remains challenging. In mammalian females ovulation and fertilization is a privilege reserved for a small number of oocytes. In reality the vast majority of oocytes formed from primordial germ cells (PGCs) will undergo apoptosis, or other forms of cell death. Removal occurs during germ cell cyst breakdown and the establishment of the primordial follicle (PF) pool, during the long dormancy at the PF stage, or through follicular atresia prior to reaching the ovulatory stage. A way to solve this limitation could be to produce large numbers of oocytes, in vitro, from stem cells. However, to recapitulate mammalian oogenesis and produce fertilizable oocytes in vitro is a complex process involving several different cell types, precise follicular cell-oocyte reciprocal interactions, a variety of nutrients and combinations of cytokines, and precise growth factors and hormones depending on the developmental stage. In 2016, two papers published by Morohaku et al. and Hikabe et al. reported in vitro procedures that appear to reproduce efficiently these conditions allowing for the production, completely in a dish, of a relatively large number of oocytes that are fertilizable and capable of giving rise to viable offspring in the mouse. The present article offers a critical overview of these results as well as other previous work performed mainly in mouse attempting to reproduce oogenesis completely in vitro and considers some perspectives for the potential to adapt the methods to produce functional human oocytes.

Histopathological studies on the cystic formation of the human urothelium.

PubMed

Noda, S; Eto, K

1990-01-01

Histopathological examination of pyeloureteritis cystica and cystitis cystica revealed the mechanisms for the cystic formation of the urothelium. Chronic stimulation with inflammation or physical stimulation with crystals or calculi causes the urothelium to form an inflammatory crypt. The crypt is isolated as a result of an adhesive occlusion of the urothelium at the orifice of the crypt. This crypt is an immature cyst that cannot be clinically detected. A von Brunn's cell nest represents a cut surface of the immature cyst. The inflammatory cyst isolated from the urinary tract, i.e., the immature cyst, gradually grows into a complete cyst, i.e., a clinically visible mature cyst, because of a hydrodynamic flow between the surrounding tissue and neogenetic capillaries, and inflammation. These findings indicate that von Brunn's cell nest, and glandular and cystic formation, occur during development from an inflammatory crypt to an immature cyst and then, a mature cyst.

Cyclin d1 expression in odontogenic cysts.

PubMed

Taghavi, Nasim; Modabbernia, Shirin; Akbarzadeh, Alireza; Sajjadi, Samad

2013-01-01

In the present study expression of cyclin D1 in the epithelial lining of odontogenic keratocyst, radicular cyst, dentigerous cyst and glandular odontogenic cyst was investigated to compare proliferative activity in these lesions. Immunohistochemical staining of cyclin D1 on formalin-fixed, paraffin-embedded tissue sections of odontogenic keratocysts (n=23), dentigerous cysts (n=20), radicular cysts (n=20) and glandular odontogenic cysts (n=5) was performed by standard EnVision method. Then, slides were studied to evaluate the following parameters in epithelial lining of cysts: expression, expression pattern, staining intensity and localization of expression. The data analysis showed statistically significant difference in cyclin D1 expression in studied groups (p < 0.001). Assessment of staining intensity and staining pattern showed more strong intensity and focally pattern in odontogenic keratocysts, but difference was not statistically significant among groups respectively (p=0.204, 0.469). Considering expression localization, cyclin D1 positive cells in odontogenic keratocysts and dentigerous cysts were frequently confined in parabasal layer, different from radicular cysts and glandular odontogenic cysts. The difference was statistically significant (p < 0.01). Findings showed higher expression of cyclin D1 in parabasal layer of odontogenic keratocyst and the entire cystic epithelium of glandular odontogenic cysts comparing to dentigerous cysts and radicular cysts, implying the possible role of G1-S cell cycle phase disturbances in the aggressiveness of odontogenic keratocyst and glandular odontogenic cyst.

The Life Cycle Stages of Pneumocystis murina Have Opposing Effects on the Immune Response to This Opportunistic Fungal Pathogen

PubMed Central

Evans, Heather M.; Bryant, Grady L.

2016-01-01

The cell wall β-glucans of Pneumocystis cysts have been shown to stimulate immune responses in lung epithelial cells, dendritic cells, and alveolar macrophages. Little is known about how the trophic life forms, which do not have a fungal cell wall, interact with these innate immune cells. Here we report differences in the responses of both neonatal and adult mice to the trophic and cystic life cycle stages of Pneumocystis murina. The adult and neonatal immune responses to infection with Pneumocystis murina trophic forms were less robust than the responses to infection with a physiologically normal mixture of cysts and trophic forms. Cysts promoted the recruitment of nonresident innate immune cells and T and B cells into the lungs. Cysts, but not trophic forms, stimulated increased concentrations of the cytokine gamma interferon (IFN-γ) in the alveolar spaces and an increase in the percentage of CD4+ T cells that produce IFN-γ. In vitro, bone marrow-derived dendritic cells (BMDCs) stimulated with cysts produced the proinflammatory cytokines interleukin 1β (IL-1β) and IL-6. In contrast, trophic forms suppressed antigen presentation to CD4+ T cells, as well as the β-glucan-, lipoteichoic acid (LTA)-, and lipopolysaccharide (LPS)-induced production of interleukin 1β (IL-1β), IL-6, and tumor necrosis factor alpha (TNF-α) by BMDCs. The negative effects of trophic forms were not due to ligation of mannose receptor. Our results indicate that optimal innate and adaptive immune responses to Pneumocystis species are dependent on stimulation with the cyst life cycle stage. Conversely, trophic forms suppress β-glucan-induced proinflammatory responses in vitro, suggesting that the trophic forms dampen cyst-induced inflammation in vivo. PMID:27572330

Signet ring cell melanocytic nevus: report of a case over trichilemmal cyst and review of the literature.

PubMed

Sabater Marco, Vicente; Escutia Muñoz, Begoña; Morera Faet, Arturo; Botella Estrada, Rafael

2012-02-01

Different melanocytic nevi have been reported as being associated with dermal cysts. Signet ring cell melanocytic nevus is a rare variant of melanocytic nevus characterized by cells with signet ring morphology within a common melanocytic nevus. This article describes an exceptional case of melanocytic nevus composed exclusively of signet ring cells over a trichilemmal cyst. Histologically, above the cyst, there was a small, symmetrical and sharply demarcated lesion showing a compound proliferation of small, round, monomorphous cells with signet ring morphology. Immunohistochemically, signet ring cells were negative for cytokeratin AE1/3, leukocyte common antigen, HMB-45, and CD34. Occasionally, isolated signet ring cells were positive for S-100 and melan A. Melanocytic nevus composed of signet ring cells should raise the differential diagnosis with other cutaneous tumors exhibiting signet ring cells. Previous cases of this entity reported in the literature are also reviewed.

An In Vitro Expansion System for Generation of Human iPS Cell-Derived Hepatic Progenitor-Like Cells Exhibiting a Bipotent Differentiation Potential

PubMed Central

Yanagida, Ayaka; Ito, Keiichi; Chikada, Hiromi; Nakauchi, Hiromitsu; Kamiya, Akihide

2013-01-01

Hepatoblasts, hepatic stem/progenitor cells in liver development, have a high proliferative potential and the ability to differentiate into both hepatocytes and cholangiocytes. In regenerative medicine and drug screening for the treatment of severe liver diseases, human induced pluripotent stem (iPS) cell-derived mature functional hepatocytes are considered to be a potentially good cell source. However, induction of proliferation of these cells is difficult ex vivo. To circumvent this problem, we generated hepatic progenitor-like cells from human iPS cells using serial cytokine treatments in vitro. Highly proliferative hepatic progenitor-like cells were purified by fluorescence-activated cell sorting using antibodies against CD13 and CD133 that are known cell surface markers of hepatic stem/progenitor cells in fetal and adult mouse livers. When the purified CD13highCD133+ cells were cultured at a low density with feeder cells in the presence of suitable growth factors and signaling inhibitors (ALK inhibitor A-83-01 and ROCK inhibitor Y-27632), individual cells gave rise to relatively large colonies. These colonies consisted of two types of cells expressing hepatocytic marker genes (hepatocyte nuclear factor 4α and α-fetoprotein) and a cholangiocytic marker gene (cytokeratin 7), and continued to proliferate over long periods of time. In a spheroid formation assay, these cells were found to express genes required for mature liver function, such as cytochrome P450 enzymes, and secrete albumin. When these cells were cultured in a suitable extracellular matrix gel, they eventually formed a cholangiocytic cyst-like structure with epithelial polarity, suggesting that human iPS cell-derived hepatic progenitor-like cells have a bipotent differentiation ability. Collectively these data indicate that this novel procedure using an in vitro expansion system is useful for not only liver regeneration but also for the determination of molecular mechanisms that regulate liver development. PMID:23935837

An in vitro expansion system for generation of human iPS cell-derived hepatic progenitor-like cells exhibiting a bipotent differentiation potential.

PubMed

Yanagida, Ayaka; Ito, Keiichi; Chikada, Hiromi; Nakauchi, Hiromitsu; Kamiya, Akihide

2013-01-01

Hepatoblasts, hepatic stem/progenitor cells in liver development, have a high proliferative potential and the ability to differentiate into both hepatocytes and cholangiocytes. In regenerative medicine and drug screening for the treatment of severe liver diseases, human induced pluripotent stem (iPS) cell-derived mature functional hepatocytes are considered to be a potentially good cell source. However, induction of proliferation of these cells is difficult ex vivo. To circumvent this problem, we generated hepatic progenitor-like cells from human iPS cells using serial cytokine treatments in vitro. Highly proliferative hepatic progenitor-like cells were purified by fluorescence-activated cell sorting using antibodies against CD13 and CD133 that are known cell surface markers of hepatic stem/progenitor cells in fetal and adult mouse livers. When the purified CD13(high)CD133(+) cells were cultured at a low density with feeder cells in the presence of suitable growth factors and signaling inhibitors (ALK inhibitor A-83-01 and ROCK inhibitor Y-27632), individual cells gave rise to relatively large colonies. These colonies consisted of two types of cells expressing hepatocytic marker genes (hepatocyte nuclear factor 4α and α-fetoprotein) and a cholangiocytic marker gene (cytokeratin 7), and continued to proliferate over long periods of time. In a spheroid formation assay, these cells were found to express genes required for mature liver function, such as cytochrome P450 enzymes, and secrete albumin. When these cells were cultured in a suitable extracellular matrix gel, they eventually formed a cholangiocytic cyst-like structure with epithelial polarity, suggesting that human iPS cell-derived hepatic progenitor-like cells have a bipotent differentiation ability. Collectively these data indicate that this novel procedure using an in vitro expansion system is useful for not only liver regeneration but also for the determination of molecular mechanisms that regulate liver development.

Immunohistochemical evaluation of podoplanin in odontogenic tumours & cysts using anti-human podoplanin antibody.

PubMed

Singhal, Namrata; Khanduri, Nitin; Kurup, Deepak; Gupta, Brijesh; Mitra, Pranjan; Chawla, Roshani

2017-01-01

Odontogenic Cysts & tumors originate through some aberration from the normal pattern of odontogenesis. Ameloblastoma is one of the most frequent intraosseous odontogenic tumors. However it is no longer appropriate to use the diagnosis of ameloblastoma without specifying the type. Varied-clinical entities of ameloblastoma differ in their biologic behaviour. Odontogenic cysts like dentigerous and radicular cysts are less aggressive in nature than odontogenic tumors. Recently, podoplanin commonly used as a lymphatic endothelial marker in cancers has recently been found to play a possible role in odontogenic tumorigenesis also. Therefore the purpose of this study was to immunohistochemically analyse the expression of podoplanin in ameloblastomas, KCOTs, dentigerous cysts, radicular cysts & dental follicles. Paraffin-embedded tissue specimens of 15 Ameloblastomas (7 follicular, 6 unicystic, 2 desmoplastic),10KCOTs, 5 dentigerous cysts, 5 radicular cysts & 5 dental follicles were immunohistochemically examined using antibody against podoplanin. All ameloblastomas displayed podoplanin expression in ameloblast-like cells of the epithelial islands while the stellate-reticulum like cells exhibited no or weak immunostaining. Expression of podoplanin in KCOTs was strongly positive in the cells of the basal and suprabasal layers & odontogenic epithelial nests. Positive immunoreaction for podoplanin was observed in the inflammatory radicular cysts and inflamed dentigerous cyst only and negative or weak expression in the lining epithelium of uninflamed dentigerous cysts and dental follicles. Our results suggest that podoplanin can be used as a potential proliferative marker to observe the aggressive behaviour of ameloblastomas and KCOTs.

High matrix metalloproteinase activity is a hallmark of periapical granulomas.

PubMed

de Paula-Silva, Francisco Wanderley Garcia; D'Silva, Nisha J; da Silva, Léa Assed Bezerra; Kapila, Yvonne Lorraine

2009-09-01

The inability to distinguish periapical cysts from granulomas before performing root canal treatment leads to uncertainty in treatment outcomes because cysts have lower healing rates. Searching for differential expression of molecules within cysts or granulomas could provide information with regard to the identity of the lesion or suggest mechanistic differences that may form the basis for future therapeutic intervention. Thus, we investigated whether granulomas and cysts exhibit differential expression of extracellular matrix (ECM) molecules. Human periapical granulomas, periapical cysts, and healthy periodontal ligament tissues were used to investigate the differential expression of ECM molecules by microarray analysis. Because matrix metalloproteinases (MMP) showed the highest differential expression in the microarray analysis, MMPs were further examined by in situ zymography and immunohistochemistry. Data were analyzed by using one-way analysis of variance followed by the Tukey test. We observed that cysts and granulomas differentially expressed several ECM molecules, especially those from the MMP family. Compared with cysts, granulomas exhibited higher MMP enzymatic activity in areas stained for MMP-9. These areas were composed of polymorphonuclear cells (PMNs) in contrast to cysts. Similarly, MMP-13 was expressed by a greater number of cells in granulomas compared with cysts. Our findings indicate that high enzymatic MMP activity in PMNs together with MMP-9 and MMP-13 stained cells could be a molecular signature of granulomas unlike periapical cysts.

High Matrix Metalloproteinase Activity is a Hallmark of Periapical Granulomas

PubMed Central

de Paula e Silva, Francisco Wanderley Garcia; D'Silva, Nisha J.; da Silva, Léa Assed Bezerra; Kapila, Yvonne Lorraine

2009-01-01

Introduction Inability to distinguish periapical cysts from granulomas prior to performing root canal treatment leads to uncertainty in treatment outcomes, because cysts have lower healing rates. Searching for differential expression of molecules within cysts or granulomas could provide information with regard to the identity of the lesion or suggest mechanistic differences that may form the basis for future therapeutic intervention. Thus, we investigated whether granulomas and cysts exhibit differential expression of extracellular matrix (ECM) molecules. Methods Human periapical granulomas, periapical cysts, and healthy periodontal ligament tissues were used to investigate the differential expression of ECM molecules by microarray analysis. Since matrix metalloproteinases (MMP) showed the highest differential expression in the microarray analysis, MMPs were further examined by in situ zymography and immunohistochemistry. Data were analyzed using one-way ANOVA followed by Tukey test. Results We observed that cysts and granulomas differentially expressed several ECM molecules, especially those from the matrix metalloproteinase (MMP) family. Compared to cysts, granulomas exhibited higher MMP enzymatic activity in areas stained for MMP-9. These areas were composed of polymorphonuclear cells (PMNs), in contrast to cysts. Similarly, MMP-13 was expressed by a greater number of cells in granulomas compared to cysts. Conclusion Our findings indicate that high enzymatic MMP activity in PMNs together with MMP-9 and MMP-13 stained cells could be a molecular signature of granulomas, unlike periapical cysts. PMID:19720222

Transitional cell carcinoma arising in a calyceal cyst mimicking a cystic renal tumour.

PubMed

Kim, Jeong Ho; Song, Joo Yeon; Lee, Wan

2014-01-01

Solitary renal cysts are relatively common. The occurrence of transitional cell carcinoma (TCC) in a renal cyst is rare. We present the case of a 59-year-old man with a medical history of viral hepatitis B. During a workup for his hepatitis, a computed tomography scan revealed a large cystic tumour in the upper region of the left kidney. A radical left nephrectomy was performed. Microscopic examination of the cystic tumour revealed a grade 2 TCC. The cyst was lined by transitional epithelium. This is a case of a TCC growing within a renal calyceal cyst.

Naegleria fowleri: enolase is expressed during cyst differentiation.

PubMed

Chávez-Munguía, Bibiana; Segovia-Gamboa, Norma; Salazar-Villatoro, Lizbeth; Omaña-Molina, Maritza; Espinosa-Cantellano, Martha; Martínez-Palomo, Adolfo

2011-01-01

Cysts of Naegleria fowleri present an external single-layered cyst wall. To date, little information exists on the biochemical components of this cyst wall. Knowledge of the cyst wall composition is important to understand its resistance capacity under adverse environmental conditions. We have used of a monoclonal antibody (B4F2 mAb) that specifically recognizes enolase in the cyst wall of Entamoeba invadens. By Western blot assays this antibody recognized in soluble extracts of N. fowleri cysts a 48-kDa protein with similar molecular weight to the enolase reported in E. invadens cysts. Immunofluorescence with the B4F2 mAb revealed positive cytoplasmic vesicles in encysting amebas, as well as a positive reaction at the cell wall of mature cysts. Immunoelectron microscopy using the same monoclonal antibody confirmed the presence of enolase in the cell wall of N. fowleri cysts and in cytoplasmic vesicular structures. In addition, the B4F2 mAb had a clear inhibitory effect on encystation of N. fowleri. © 2011 The Author(s). Journal of Eukaryotic Microbiology © 2011 International Society of Protistologists.

Research Update: Electrical monitoring of cysts using organic electrochemical transistors a

NASA Astrophysics Data System (ADS)

Huerta, M.; Rivnay, J.; Ramuz, M.; Hama, A.; Owens, R. M.

2015-03-01

Organotypic three-dimensional (3D) cell culture models have the potential to act as surrogate tissues in vitro, both for basic research and for drug discovery/toxicology. 3D cultures maintain not only 3D architecture but also cell-cell and cell extracellular matrix interactions, particularly when grown in cysts or spheroids. Characterization of cell cultures grown in 3D formats, however, provides a significant challenge for cell biologists due to the incompatibility of these structures with commonly found optical or electronic monitoring systems. Electronic impedance spectroscopy is a cell culture monitoring technique with great potential; however, it has not been possible to integrate 3D cultures with commercially available systems to date. Cyst-like 3D cultures are particularly challenging due to their small size and difficulty in manipulation. Herein, we demonstrate isolation of cyst-like 3D cultures by capillarity and subsequent integration with the organic electrochemical transistor for monitoring the integrity of these structures. We show not only that this versatile device can be adapted to the cyst format for measuring resistance and, therefore, the quality of the cysts, but also can be used for quantitative monitoring of the effect of toxic compounds on cells in a 3D format. The ability to quantitatively predict effects of drugs on 3D cultures in vitro has large future potential for the fields of drug discovery and toxicology.

Research Update: Electrical monitoring of cysts using organic electrochemical transistors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huerta, M.; Rivnay, J.; Ramuz, M.

2015-03-01

Organotypic three-dimensional (3D) cell culture models have the potential to act as surrogate tissues in vitro, both for basic research and for drug discovery/toxicology. 3D cultures maintain not only 3D architecture but also cell-cell and cell extracellular matrix interactions, particularly when grown in cysts or spheroids. Characterization of cell cultures grown in 3D formats, however, provides a significant challenge for cell biologists due to the incompatibility of these structures with commonly found optical or electronic monitoring systems. Electronic impedance spectroscopy is a cell culture monitoring technique with great potential; however, it has not been possible to integrate 3D cultures withmore » commercially available systems to date. Cyst-like 3D cultures are particularly challenging due to their small size and difficulty in manipulation. Herein, we demonstrate isolation of cyst-like 3D cultures by capillarity and subsequent integration with the organic electrochemical transistor for monitoring the integrity of these structures. We show not only that this versatile device can be adapted to the cyst format for measuring resistance and, therefore, the quality of the cysts, but also can be used for quantitative monitoring of the effect of toxic compounds on cells in a 3D format. The ability to quantitatively predict effects of drugs on 3D cultures in vitro has large future potential for the fields of drug discovery and toxicology.« less

Concentrated Growth Factor Enhanced Fat Graft Survival: A Comparative Study.

PubMed

Hu, Yun; Jiang, Yichen; Wang, Muyao; Tian, Weidong; Wang, Hang

2018-06-08

Concentrated growth factors (CGFs) belong to a new generation biomaterials that concentrate large number of growth factors and CD34 stem cells in small volume of plasma. The purpose of this study was to evaluate the impact of the new technique, CGF, on fat graft survival, which compared with platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). Nude mice received fat graft were divided into PRP group, PRF group, CGF group, and saline. The grafts were volumetrically and histologically evaluated at 4, 8, and 12 weeks after fat grafting. In vitro growth factor levels in PRP, PRF, and CGF were compared using enzyme-linked immunoassay method. Cell count and real-time polymerase chain reaction were used to evaluate the impact of CGF in medium on human adipose-derived stem cell (hADSC) proliferation and vascular differentiation, respectively. Fat graft weight was significantly higher in the CGF group than those in the other groups, and histologic evaluation revealed greater vascularity, fewer cysts, and less fibrosis. Adding CGF to the medium maximally promoted hADSC proliferation and expressing vascular endothelial growth factor and PECAM-1. In this preliminary study, CGF treatment improved the survival and quality of fat grafts.

The role of osteoblast cells in the pathogenesis of unicameral bone cysts.

PubMed

Aarvold, Alexander; Smith, James O; Tayton, Edward R; Edwards, Caroline J; Fowler, Darren J; Gent, Edward D; Oreffo, Richard O C

2012-08-01

The pathogenesis of unicameral bone cysts (UBCs) remains largely unknown. Osteoclasts have been implicated, but the role of osteoblastic cells has, to date, not been explored. This study investigated the pathophysiology of UBCs by examining the interactions between the cyst fluid and human bone marrow stromal cells (hBMSCs) and the effect of the fluid on osteogenesis. Fluid was aspirated from two UBCs and analysed for protein, electrolyte and cytokine levels. Graded concentrations of the fluid were used as culture media for hBMSCs to determine the effects of the fluid on hBMSC proliferation and osteogenic differentiation. The fibrocellular lining was analysed histologically and by electron microscopy. Alkaline phosphatase (ALP) staining of hBMSCs that were cultured in cyst fluid demonstrated increased cell proliferation and osteogenic differentiation compared to basal media controls. Biochemical analysis of these hBMSCs compared to basal controls confirmed a marked increase in DNA content (as a marker of proliferation) and ALP activity (as a marker of osteogenic differentiation) which was highly significant (p < 0.001). Osteoclasts were demonstrated in abundance in the cyst lining. The cyst fluid cytokine profile revealed levels of the pro-osteoclast cytokines IL-6, MIP-1α and MCP-1 that were 19×, 31× and 35× greater than those in reference serum. Cyst fluid promoted osteoblastic growth and differentiation. Despite appearing paradoxical that the cyst fluid promoted osteogenesis, osteoblastic cells are required for osteoclastogenesis through RANKL signalling. Three key cytokines in this pathway (IL-6, MIP-1α, MCP-1) were highly elevated in cyst fluid. These findings may hold the key to the pathogenesis of UBCs, with implications for treatment methods.

Paratesticular cysts with benign epithelial proliferations of wolffian origin.

PubMed

Nistal, Manuel; González-Peramato, Pilar; Serrano, Alvaro; Vega-Perez, Maria; De Miguel, Maria P; Regadera, Javier

2005-08-01

Paratesticular cysts with benign epithelial proliferations (BEPs) are rare. Only 10 cases were found in a series of 431 paratesticular cysts and were classified as follows: cystadenoma, 5; papilloma, 2; and hamartoma, 3. Four cystadenomas showed multiple papillae lined by CD10+ epithelial cells with hyperchromatic nuclei. The remaining lesion showed areas with a microcystic, glandular, cribriform pattern, with small, benign glands without atypia. Urothelial papilloma presented BEPs with cytokeratin (CK) 7+ and CD10+ and CK20- umbrella-like cells. The mural papilloma was lined by proliferative cylindrical cells exhibiting strong CK7 and CD10 expression. The 3 Wolffian hamartomas were characterized by strongly CD10+ epithelium surrounded by smooth muscle cells. The consistent CD10 expression in BEPs of paratesticular cysts suggests a Wolffian origin. The differential diagnosis of paratesticular cysts with BEP vs metastatic prostatic and primary borderline or malignant tumors is discussed.

Alexandrium fundyense cyst viability and germling survival in light vs. dark at a constant low temperature

NASA Astrophysics Data System (ADS)

Vahtera, Emil; Crespo, Bibiana G.; McGillicuddy, Dennis J.; Olli, Kalle; Anderson, Donald M.

2014-05-01

Both observations and models suggest that large-scale coastal blooms of Alexandrium fundyense in the Gulf of Maine are seeded by deep-bottom cyst accumulation zones (“seed beds”) where cysts germinate from the sediment surface or the overlying near-bottom nepheloid layers at water depths exceeding 100 m. The germling cells and their vegetative progeny are assumed to be subject to mortality while in complete darkness, as they swim to illuminated surface waters. To test the validity of this assumption we conducted laboratory investigations of cyst viability and the survival of the germling cells and their vegetative progeny during prolonged exposure to darkness at a temperature of 6 °C, simulating the conditions in deep Gulf of Maine waters. We isolated cysts from bottom sediments collected in the Gulf of Maine under low red light and incubated them in 96-well tissue culture-plates in culture medium under a 10:14 h light:dark cycle and under complete darkness. Cyst viability was high, with excystment frequency reaching 90% in the illuminated treatment after 30 days and in the dark treatment after 50 days. Average germination rates were 0.062 and 0.038 d-1 for light and dark treatments, respectively. The dark treatment showed an approximately 2-week time lag in maximum germination rates compared to the light treatment. Survival of germlings was considerably lower in the dark treatment. In the light treatments, 47% of germinated cysts produced germlings that were able to survive for 7 days and produce vegetative progeny, i.e., there were live cells in the well along with an empty cyst at least once during the experiment. In the dark treatments 12% of the cysts produced germlings that were able to survive for the same length of time. When dark treatments are scaled to take into account non-darkness related mortality, approximately 28% of the cysts produced germlings that were able to survive for at least 7 days. Even though cysts are able to germinate in darkness, the lack of illumination considerably reduces survival rate of germling cells. In addition to viability of cysts in surface sediments and the near-bottom nepheloid layer, survivability of germling cells and their vegetative progeny at aphotic depths is an important consideration in assessing the quantitative role of deep-coastal cyst seed beds in bloom formation.

Increasing extracellular matrix collagen level and MMP activity induces cyst development in polycystic kidney disease.

PubMed

Liu, Bin; Li, Chenghai; Liu, Zijuan; Dai, Zonghan; Tao, Yunxia

2012-09-11

Polycystic Kidney Disease (PKD) kidneys exhibit increased extracellular matrix (ECM) collagen expression and metalloproteinases (MMPs) activity. We investigated the role of these increases on cystic disease progression in PKD kidneys. We examined the role of type I collagen (collagen I) and membrane bound type 1 MMP (MT1-MMP) on cyst development using both in vitro 3 dimensional (3D) collagen gel culture and in vivo PCK rat model of PKD. We found that collagen concentration is critical in controlling the morphogenesis of MDCK cells cultured in 3D gels. MDCK cells did not form 3D structures at collagen I concentrations lower than 1 mg/ml but began forming tubules when the concentration reaches 1 mg/ml. Significantly, these cells began to form cyst when collagen I concentration reached to 1.2 mg/ml, and the ratios of cyst to tubule structures increased as the collagen I concentration increased. These cells exclusively formed cyst structures at a collagen I concentration of 1.8 mg/ml or higher. Overexpression of MT1-MMP in MDCK cells significantly induced cyst growth in 3D collagen gel culture. Conversely, inhibition of MMPs activity with doxycycline, a FDA approved pan-MMPs inhibitor, dramatically slowed cyst growth. More importantly, the treatment of PCK rats with doxycycline significantly decreased renal tubule cell proliferation and markedly inhibited the cystic disease progression. Our data suggest that increased collagen expression and MMP activity in PKD kidneys may induce cyst formation and expansion. Our findings also suggest that MMPs may serve as a therapeutic target for the treatment of human PKD.

Transitional cell carcinoma of the retrorectal space arisen in tailgut cyst: a case report and review of the literature.

PubMed

Vinciguerra, Gian Luca Rampioni; Mercantini, Paolo; La Torre, Marco; Pilozzi, Emanuela; Ziparo, Vincenzo; Vecchione, Andrea

2014-05-01

Tailgut cysts, also known as retrorectal cystic hamartomas, are congenital lesions derived by an abnormal remnant of the postanal primitive hindgut, consisting of unilocular or multilocular cysts usually lined by squamous, transitional, or glandular epithelium. Malignant transformation is an uncommon event, and it mainly involves the neuroendocrine or glandular epithelium; other histotypes are sporadic. Here, we report, for the first time, the clinicopathological features of a transitional cell carcinoma that arose in a tailgut cyst.

A rare cause of childhood renal cysts: Xp11.2 translocation renal cell carcinoma

PubMed Central

Taşkınlar, Hakan; Avlan, Dinçer; Çıtak, Çağlar; Polat, Ayşe; Naycı, Ali

2015-01-01

Pediatric renal cysts are rare, usually asymptomatic and incidentally detected in children. Cyst associated renal cell carcinoma (RCC) or cystic RCC is extremely rare in children. Bosniak classification system has been accepted for the management of cystic renal masses. Xp11.2 translocation RCC is a recently classified distinct subtype and usually affects children and adolescents. We report the case of a 10-year-old girl with Xp11.2 translocation RCC from a cyst of the right kidney. PMID:25624966

A rare cause of childhood renal cysts: Xp11.2 translocation renal cell carcinoma.

PubMed

Taşkınlar, Hakan; Avlan, Dinçer; Çıtak, Çağlar; Polat, Ayşe; Naycı, Ali

2015-01-01

Pediatric renal cysts are rare, usually asymptomatic and incidentally detected in children. Cyst associated renal cell carcinoma (RCC) or cystic RCC is extremely rare in children. Bosniak classification system has been accepted for the management of cystic renal masses. Xp11.2 translocation RCC is a recently classified distinct subtype and usually affects children and adolescents. We report the case of a 10-year-old girl with Xp11.2 translocation RCC from a cyst of the right kidney.

Stem cell autotomy and niche interaction in different systems

PubMed Central

Dorn, David C; Dorn, August

2015-01-01

The best known cases of cell autotomy are the formation of erythrocytes and thrombocytes (platelets) from progenitor cells that reside in special niches. Recently, autotomy of stem cells and its enigmatic interaction with the niche has been reported from male germline stem cells (GSCs) in several insect species. First described in lepidopterans, the silkmoth, followed by the gipsy moth and consecutively in hemipterans, foremost the milkweed bug. In both, moths and the milkweed bug, GSCs form finger-like projections toward the niche, the apical cells (homologs of the hub cells in Drosophila). Whereas in the milkweed bug the projection terminals remain at the surface of the niche cells, in the gipsy moth they protrude deeply into the singular niche cell. In both cases, the projections undergo serial retrograde fragmentation with progressing signs of autophagy. In the gipsy moth, the autotomized vesicles are phagocytized and digested by the niche cell. In the milkweed bug the autotomized vesicles accumulate at the niche surface and disintegrate. Autotomy and sprouting of new projections appears to occur continuously. The significance of the GSC-niche interactions, however, remains enigmatic. Our concept on the signaling relationship between stem cell-niche in general and GSC and niche (hub cells and cyst stem cells) in particular has been greatly shaped by Drosophila melanogaster. In comparing the interactions of GSCs with their niche in Drosophila with those in species exhibiting GSC autotomy it is obvious that additional or alternative modes of stem cell-niche communication exist. Thus, essential signaling pathways, including niche-stem cell adhesion (E-cadherin) and the direction of asymmetrical GSC division - as they were found in Drosophila - can hardly be translated into the systems where GSC autotomy was reported. It is shown here that the serial autotomy of GSC projections shows remarkable similarities with Wallerian axonal destruction, developmental axon pruning and dying-back degeneration in neurodegenerative diseases. Especially the hypothesis of an existing evolutionary conserved “autodestruction program” in axons that might also be active in GSC projections appears attractive. Investigations on the underlying signaling pathways have to be carried out. There are two other well known cases of programmed cell autotomy: the enucleation of erythroblasts in the process of erythrocyte maturation and the segregation of thousands of thrombocytes (platelets) from one megakaryocyte. Both progenitor cell types - erythroblasts and megakaryocytes - are associated with a niche in the bone marrow, erythroblasts with a macrophage, which they surround, and the megakaryocytes with the endothelial cells of sinusoids and their extracellular matrix. Although the regulatory mechanisms may be specific in each case, there is one aspect that connects all described processes of programmed cell autotomy and neuronal autodestruction: apoptotic pathways play always a prominent role. Studies on the role of male GSC autotomy in stem cell-niche interaction have just started but are expected to reveal hitherto unknown ways of signal exchange. Spermatogenesis in mammals advance our understanding of insect spermatogenesis. Mammal and insect spermatogenesis share some broad principles, but a comparison of the signaling pathways is difficult. We have intimate knowledge from Drosophila, but of almost no other insect, and we have only limited knowledge from mammals. The discovery of stem cell autotomy as part of the interaction with the niche promises new general insights into the complicated stem cell-niche interdependence. PMID:26240680

Disappearance of Renal Cysts Included in Ice Ball During Cryoablation of Renal-Cell Carcinoma: A Potential Therapy for Symptomatic Renal Cysts?

PubMed

Yodoya, Mitsuko; Hiraki, Takao; Iguchi, Toshihiro; Fujiwara, Hiroyasu; Matsui, Yusuke; Masaoka, Yoshihisa; Sakurai, Jun; Mitsuhashi, Toshiharu; Gobara, Hideo; Kanazawa, Susumu

2017-06-01

To retrospectively evaluate the effect of cryoablation of renal-cell carcinoma on nearby renal cysts with the goal to investigate the potential for an alternative therapy to treat symptomatic renal cysts. The study population comprised 46 cysts (mean size, 12 mm; range, 5-43 mm) that were within or near the ice ball during cryoablation in 22 patients. Size change of each cyst was evaluated via enhanced CT or MR imaging before and 1, 3, 6, and 12 months after cryoablation. Forty-one cysts were also followed after 12 months. Variables including positional relationship between the cyst and the ice ball were evaluated via linear regression analysis using generalized estimating equation models to determine which factors affected cyst shrinkage rate at 12 months. Fifteen, 12, and 19 cysts were completely included in, partially included in, or excluded from the ice ball, respectively. The overall shrinkage rate was 62%, and 57% of cysts (26 of 46) had disappeared at 12 months. Only the relationship between the cyst and the ice ball was significantly (P < .001) associated with cyst shrinkage rate. Cyst disappearance rates at 12 months were 100% (15 of 15), 67% (8 of 12), and 16% (3 of 19) for cysts completely included, partially included, and excluded from the ice ball, respectively. Among the 22 cysts that disappeared at 12 months and continued to be followed, none recurred after 12 months. All renal cysts that were completely included in the ice ball disappeared after cryoablation, demonstrating the potential utility of cryoablation as an alternative therapy for symptomatic renal cysts. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

The value of fine needle aspiration and cytologic examination of impalpable complicated breast cysts.

PubMed

Tez, Selda; Dener, Cenap; Köktener, Aslý; Caydere, Muzaffer; Tez, Mesut

2008-01-01

The purpose of the study was to evaluate the utility of fine needle aspiration--FNA and cytologic analysis of impalpable complicated breast cysts. We rewieved the imaging findings, aspiration, cytology and biopsy results and followup imaging findings of 246 complicated cysts in 166 women retrospectively. FNA was performed in 169 out of the 246 complicated cysts. Thirtyone lesions were followed-up with US. Surgical biopsy was performed from five lesions. No malignant cells (137 cysts), insufficient cellular material (17 cysts), atypical cells (4 cysts) were seen in cytological examination of the aspirates. None of these lesions were found to represent malignancy at the time of surgical excision and during follow-up. Impalpable complicated breast cysts may be classified as probably benign and can be managed with follow-up imaging studies instead of intervention. Routine cytologic examination is unnecessary if the fluid is not bloody (Tab. 2, Ref. 18). Full Text (Free, PDF) www.bmj.sk.

Immunohistochemical Assessment of Mast Cells and Small Blood Vessels in Dentigerous Cyst, Odontogenic Keratocyst, and Periapical Cyst

PubMed Central

Kouhsoltani, Maryam; Moradzadeh Khiavi, Monir; Jamali, Golshan; Farnia, Samira

2015-01-01

Purpose: The aim of this study was to verify the density of mast cells (MCs) and microvessels in odontogenic cysts. Furthermore, the correlation between MCs and microvessels was evaluated to assess the contribution of MCs to angiogenesis and growth of odontogenic cysts. This approach may be a basis for the development of future pharmaceuticals addressed to MCs performance to manage odontogenic cysts. To our knowledge, no study investigating the correlation between MCs and microvessels has been performed to date. Methods: 60 cases of odontogenic cysts consisting of 20 radicular cysts (RCs), 20 odontogenic keratocysts (OKCs) and 20 dentigerous cysts (DCs) were included in this study. Five high power fields in superficial connective tissue and five high power fields in deep connective tissue were counted for each sample. Moreover, a total mean of ten fields was calculated. Results: RC showed the highest mean numbers of MCs and microvessels (p<0.05). The subepithelial zones of all cysts contained more MCs and microvessels compared to the deeper zones. A statistically significant correlation between the numbers of MCs and microvessels was not observed (r=0.00, p=0.49). Conclusion: Although the number of MCs was not significantly associated with microvessels, these cells may be related to the growth of odontogenic lesions, particularly RCs. Further studies on the in vivo functions of MCs will make the concept more clear. PMID:26793609

Immunohistochemical Assessment of Mast Cells and Small Blood Vessels in Dentigerous Cyst, Odontogenic Keratocyst, and Periapical Cyst.

PubMed

Kouhsoltani, Maryam; Moradzadeh Khiavi, Monir; Jamali, Golshan; Farnia, Samira

2015-12-01

The aim of this study was to verify the density of mast cells (MCs) and microvessels in odontogenic cysts. Furthermore, the correlation between MCs and microvessels was evaluated to assess the contribution of MCs to angiogenesis and growth of odontogenic cysts. This approach may be a basis for the development of future pharmaceuticals addressed to MCs performance to manage odontogenic cysts. To our knowledge, no study investigating the correlation between MCs and microvessels has been performed to date. 60 cases of odontogenic cysts consisting of 20 radicular cysts (RCs), 20 odontogenic keratocysts (OKCs) and 20 dentigerous cysts (DCs) were included in this study. Five high power fields in superficial connective tissue and five high power fields in deep connective tissue were counted for each sample. Moreover, a total mean of ten fields was calculated. RC showed the highest mean numbers of MCs and microvessels (p<0.05). The subepithelial zones of all cysts contained more MCs and microvessels compared to the deeper zones. A statistically significant correlation between the numbers of MCs and microvessels was not observed (r=0.00, p=0.49). Although the number of MCs was not significantly associated with microvessels, these cells may be related to the growth of odontogenic lesions, particularly RCs. Further studies on the in vivo functions of MCs will make the concept more clear.

Toxoplasma gondii tissue cyst purification using Percoll gradients

PubMed Central

Watts, Elizabeth A.; Dhara, Animesh; Sinai, Anthony P.

2017-01-01

The protozoan parasite Toxoplasma gondii is capable of infecting all warm blooded animals and humans. Infectious, transmissible forms of the parasite include oocysts produced by the sexual cycle within the definitive feline host and tissue cysts that form Toxoplasma in the CNS and muscle during the asexual cycle within all chronically infected warm-blooded hosts. These tissue cysts are populated with slow growing bradyzoites which have been until recently thought to be dormant entities in the context of immune sufficiency. Reactivation to active growth during immune suppression is of critical clinical importance. Yet we know little about tissue cysts or the bradyzoites they house as the diversity of tissue cysts cannot be replicated in cell culture systems. Our optimization of tissue cyst purification from the brains of infected mice using Percoll gradients provides an efficient means to recover in vivo derived tissue cysts that can be applied to imaging, cell-biologic, biochemical, transcriptomic and proteomic analyses. PMID:28510363

Immunomodulatory activity of interleukin-27 in human chronic periapical diseases.

PubMed

Li, Juan; Wang, Rong; Huang, Shi-Guang

2017-01-01

This study aims to observe expression of IL-27 on different cells in periapical tissues of different types of human chronic periapical diseases. Periapical tissue specimens of 60 donors, including healthy control (n=20), periapical granuloma group (n=20) and radicular cysts group (n=20), were fixed in 10% buffered formalin, stained with hematoxylin and eosin for histopathology. Then specimens were stained with double- immuno-fluorescence assay for identification of IL-27-tryptase (mast cells, MCs), IL-27-CD14 (mononuclear phagocyte cells, MPs) and IL-27-CD31 (endothelial cells, ECs) double-positive cells in periapical tissues. The results indicated that compared with healthy control, the densities (cells/mm 2 ) of IL-27-tryptase, IL-27-CD14 and IL-27-CD31 double-positive cells were significantly increased in human chronic periapical diseases (periapical granuloma group and radicular cysts group) ( P <0.001). The density of IL-27-tryptase double positive cells in radicular cysts group was significantly higher than those in periapical granuloma group ( P <0.001). Densities of IL-27-CD14 and IL-27-CD31 double-positive cells in periapical granuloma group had no significant difference with those in radicular cysts group ( P =0.170 and 0.138, respectively). IL-27-CD14 double positive cells density achieved to peak among three cell groups in radicular cysts groups. In conclusion, IL-27 expressed in MCs, MPs and ECs of human chronic periapical diseases with different degrees. IL-27-tryptase double-positive cells may participate in pathogenic mechanism of chronic periapical diseases, especially for formation of fibrous in periapical cysts. IL-27-CD14 and IL-27-CD31 double-positive cells may participate in immunologic response to resist periapical infection, and they may play an dual role in pathogenesis and localization of periapical diseases.

The incidence of satellite cysts in keratocystic odontogenic tumors.

PubMed

Pavelić, Boiidar; Katunarić, Marina; Segović, Sanja; Karadole, Maja Cimas; Katanec, Davor; Saban, Aida; Puhar, Ivan

2014-03-01

Renaming of the Odontogenic Keratocyst as the Keratocystic Odontogenic Tumor by the World Health Organization (WHO) is based on the aggressive nature of this lesion. Satellite cysts founded in the walls of the original cysts may give rise to a new lesion formation. The aim of this retrospecitve study was to identify the existence of specific features according incidence of satellite cysts and the pallisading of the basal layer of the epithelium and to establish their mutual correlation. The histopathologic data of Keratocystic Odontogenic Tumor on the basis of new WHO's classification (2005) were analized. Prominent palisade basal cell layer was found in 415 (94.75%) and partially absent palisade basal cell layer in 23 (5.25%) cases. Satellite cysts were presented in prominent palisade basal cell layer in 85 specimens (20.5%) and in cases with partial absent of the palisade basal layer in 3 spicemens (13%). The higher the frequency of pallisading was the higher the frequency of satellite cysts was (p > 0.05).

Mycophenolic acid induces differentiation of Toxoplasma gondii RH strain tachyzoites into bradyzoites and formation of cyst-like structure in vitro.

PubMed

Castro-Elizalde, Kitzia N; Hernández-Contreras, Pedro; Ramírez-Flores, Carlos J; González-Pozos, Sirenia; Gómez de León, Carmen T; Mondragón-Castelán, Mónica; Mondragón-Flores, Ricardo

2018-02-01

The biochemical and structural changes that occur during the conversion of Toxoplasma gondii tachyzoites to bradyzoites and the formation of tissue cyst are not well understood. Maintaining cells infected with T. gondii type II and III strains under stress conditions induces the tachyzoite-bradyzoite in vitro differentiation, along with the formation of cyst-like structures. However, due to the long exposure to such conditions required to induce the differentiation, the severe damages in the host cell and the low encystation frequency, it has been difficult to dissect in more detail these processes. Here, we successfully induced the in vitro formation of Toxoplasma cysts-like structures from tachyzoites of the type I RH strain by treating with mycophenolic acid, an inhibitor of the inosine monophosphate dehydrogenase. Mycophenolic acid is a drug widely used for HXGPRT positive selection of Toxoplasma mutant strains along with xanthine incubation in the culture medium; under such conditions, formation of tissue cysts has not been reported. We show that the exposure of extracellular tachyzoites to mycophenolic acid in absence of xanthine, followed by host cell invasion, triggered their differentiation into cyst-like structures. The differential expression of CST1, BAG1, and SAG1 molecules, as well as the structural modifications of infected cells, was characterized during the formation of cyst-like structures in vitro. These findings will allow the characterization of signaling pathways involved in tachyzoite to bradyzoite conversion and formation of tissue cysts.

Comparative Expression of CD34, Intercellular Adhesion Molecule-1, and Podoplanin and the Presence of Mast Cells in Periapical Granulomas, Cysts, and Residual Cysts.

PubMed

Lopes, Cristiane Barbosa; Armada, Luciana; Pires, Fábio Ramôa

2018-07-01

The aim of the present study was to compare the immunoexpression of CD34, intercellular adhesion molecule-1 (ICAM-1), and podoplanin and the presence of mast cells with clinical, demographic, radiologic, and histologic features from periapical granulomas, periapical cysts, and residual cysts. Thirty-one lesions (5 granulomas, 15 periapical cysts, and 11 residual cysts) were selected. Histologic sections in silanized slides were used for the immunohistochemical reactions. The analysis of the images was performed by using an optical microscope, and data were analyzed with 5% significance (P < .05). Cysts presented atrophic and hyperplastic epithelium in 11 cases (35.5%) and 15 cases (48.8%), respectively (P > .05). The intensity of the inflammatory infiltrate was similar when comparing the 3 groups (P > .05). CD34 and podoplanin expression and the presence of mast cells were similar when comparing the 3 groups; ICAM-1 expression was more intense in granulomas than cysts (P < .05). There were no statistically significant differences associated with the expression of the evaluated markers according to the intensity of the inflammatory infiltrate. There were no differences in the expression of CD34 and podoplanin and in the presence of mast cells when the 3 groups were compared. ICAM-1 expression was more common in periapical granulomas. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Odontogenic Cysts and Neoplasms.

PubMed

Bilodeau, Elizabeth Ann; Collins, Bobby M

2017-03-01

This article reviews a myriad of common and uncommon odontogenic cysts and tumors. The clinical presentation, gross and microscopic features, differential diagnosis, prognosis, and diagnostic pitfalls are addressed for inflammatory cysts (periapical cyst, mandibular infected buccal cyst/paradental cyst), developmental cysts (dentigerous, lateral periodontal, glandular odontogenic, orthokeratinized odontogenic cyst), benign tumors (keratocystic odontogenic tumor, ameloblastoma, adenomatoid odontogenic tumor, calcifying epithelial odontogenic tumor, ameloblastic fibroma and fibroodontoma, odontoma, squamous odontogenic tumor, calcifying cystic odontogenic tumor, primordial odontogenic tumor, central odontogenic fibroma, and odontogenic myxomas), and malignant tumors (clear cell odontogenic carcinoma, ameloblastic carcinoma, ameloblastic fibrosarcoma). Copyright © 2016 Elsevier Inc. All rights reserved.

Optimization of FNAC findings as a preoperative diagnostic aid for odontogenic cysts.

PubMed

Jain, Garima; Shetty, Pushparaja

2015-01-01

Fine-needle aspiration cytology (FNAC) is not a definitive preoperative diagnostic procedure done for all cases of odontogenic cysts. This is because of the inconsistent results obtained with it. This study was done to optimize FNAC findings and help in preoperative characterization of odontogenic cysts. Cystic fluid was collected and centrifuged from 50 odontogenic cysts that were planned for excision. Three smears were prepared from the cell sediment obtained after centrifugation and stained. The stained sections were examined for presence and type of epithelial cells, to formulate a preopererative diagnosis. Epithelial cells were detected in 46% cases in smear 1, 48% cases in smear 2, and 52% cases in smear 3. When all three smears from one case were studied, 86% cases showed epithelial cells for evaluation. Cystic aspirate should be centrifuged and the entire cell sediment should be examined by making multiple smears for evaluation of cystic epithelial lining cells.

Quantification and localization of mast cells in periapical lesions.

PubMed

Mahita, V N; Manjunatha, B S; Shah, R; Astekar, M; Purohit, S; Kovvuru, S

2015-01-01

Periapical lesions occur in response to chronic irritation in periapical tissue, generally resulting from an infected root canal. Specific etiological agents of induction, participating cell population and growth factors associated with maintenance and resolution of periapical lesions are incompletely understood. Among the cells found in periapical lesions, mast cells have been implicated in the inflammatory mechanism. Quantifications and the possible role played by mast cells in the periapical granuloma and radicular cyst. Hence, this study is to emphasize the presence (localization) and quantification of mast cells in periapical granuloma and radicular cyst. A total of 30 cases and out of which 15 of periapical granuloma and 15 radicular cyst, each along with the case details from the previously diagnosed cases in the department of oral pathology were selected for the study. The gender distribution showed male 8 (53.3%) and females 7 (46.7%) in periapical granuloma cases and male 10 (66.7%) and females 5 (33.3%) in radicular cyst cases. The statistical analysis used was unpaired t-test. Mean mast cell count in periapical granuloma subepithelial and deeper connective tissue, was 12.40 (0.99%) and 7.13 (0.83%), respectively. The mean mast cell counts in subepithelial and deeper connective tissue of radicular cyst were 17.64 (1.59%) and 12.06 (1.33%) respectively, which was statistically significant. No statistical significant difference was noted among males and females. Mast cells were more in number in radicular cyst. Based on the concept that mast cells play a critical role in the induction of inflammation, it is logical to use therapeutic agents to alter mast cell function and secretion, to thwart inflammation at its earliest phases. These findings may suggest the possible role of mast cells in the pathogenesis of periapical lesions.

Anti-Muellerian hormone concentration in bitches with histopathologically diagnosed ovarian tumours and cysts.

PubMed

Walter, B; Coelfen, A; Jäger, K; Reese, S; Meyer-Lindenberg, A; Aupperle-Lellbach, H

2018-06-01

Increased concentrations of Anti-Muellerian hormone (AMH) can indicate a granulosa cell tumour as shown in women, mares and cows. To investigate AMH to differentiate canine granulosa cell tumour from other ovarian pathologies, we evaluated the ovaries of 63 bitches. Blood serum samples were collected before surgery for AMH analysis. Ovaries were submitted for histopathological examination. Fourteen bitches showed normal ovaries. These bitches had AMH values between 0.12 and 0.99 ng/ml. In 20 bitches ovarian cysts i.e., follicular cysts (n = 8), corpora lutea cysts (n = 7), subsurface cysts (n = 5) were diagnosed. These dogs had AMH values of 0.11-2.09 ng/ml. Bitches with small luteinized follicular cysts had slightly higher AMH values than those without ovarian alteration. In 29 cases ovarian neoplasms i.e., granulosa cell tumour (n = 9), epithelial tumours (n = 16), dysgerminomas (n = 3) and one sarcoma were identified. Anti-Muellerian hormone values of bitches with an ovarian neoplasm except granulosa cell tumour ranged from 0.18 to 1.18 ng/ml. The AMH values of bitches with granulosa cell tumour ranged from 1.12 to ≤23 ng/ml and were significantly higher (p < .05) than in all of the other bitches. The cut-off of 0.99 ng/ml gave a sensitivity of 100% and a specificity of 94.44% to diagnose granulosa cell tumour. In conclusion, markedly elevated AMH concentrations in bitches are indicative for a granulosa cell tumour. However, negative testing does not rule out the existence of small one. Differentiation of GCT from luteinized follicular cysts may especially be difficult. © 2018 Blackwell Verlag GmbH.

The Social Amoeba Polysphondylium pallidum Loses Encystation and Sporulation, but Can Still Erect Fruiting Bodies in the Absence of Cellulose

PubMed Central

Du, Qingyou; Schaap, Pauline

2014-01-01

Amoebas and other freely moving protists differentiate into walled cysts when exposed to stress. As cysts, amoeba pathogens are resistant to biocides, preventing treatment and eradication. Lack of gene modification procedures has left the mechanisms of encystation largely unexplored. Genetically tractable Dictyostelium discoideum amoebas require cellulose synthase for formation of multicellular fructifications with cellulose-rich stalk and spore cells. Amoebas of its distant relative Polysphondylium pallidum (Ppal), can additionally encyst individually in response to stress. Ppal has two cellulose synthase genes, DcsA and DcsB, which we deleted individually and in combination. Dcsa- mutants formed fruiting bodies with normal stalks, but their spore and cyst walls lacked cellulose, which obliterated stress-resistance of spores and rendered cysts entirely non-viable. A dcsa-/dcsb- mutant made no walled spores, stalk cells or cysts, although simple fruiting structures were formed with a droplet of amoeboid cells resting on an sheathed column of decaying cells. DcsB is expressed in prestalk and stalk cells, while DcsA is additionally expressed in spores and cysts. We conclude that cellulose is essential for encystation and that cellulose synthase may be a suitable target for drugs to prevent encystation and render amoeba pathogens susceptible to conventional antibiotics. PMID:25113829

PD-1 immune checkpoint blockade promotes brain leukocyte infiltration and diminishes cyst burden in a mouse model of Toxoplasma infection.

PubMed

Xiao, Jianchun; Li, Ye; Yolken, Robert H; Viscidi, Raphael P

2018-06-15

Tissue cysts, the hallmark of chronic Toxoplasma gondii infection, are predominantly located in the brain making clearance of the parasite difficult. Currently available anti-T. gondii drugs are ineffective on cysts and fail to prevent reactivation of latent toxoplasmosis. We examined whether abrogation of inhibitory signaling pathways that maintain T cells in an exhausted state can be exploited for treating T. gondii tissue cysts. By using a mouse model of chronic toxoplasmosis, we showed immune checkpoint blockade directed against the programmed death-1 (PD-1) pathway results in a significant reduction in brain cyst number (77% lower). We showed leukocyte infiltration (CD3+ T cells, CD8+ T cells, and CD11b + cells) in the leptomeninges, choroid plexus, and subependymal tissue, which are known routes of entry of immune cells into the brain, and in proximal brain parenchyma. Our study provides proof of concept for blockade of immune checkpoint inhibitors as a therapy for chronic toxoplasmosis and potentially for other brain pathogens. Copyright © 2018 Elsevier B.V. All rights reserved.

Renal cyst formation in patients treated with crizotinib for non-small cell lung cancer-Incidence, radiological features and clinical characteristics.

PubMed

Halpenny, Darragh F; McEvoy, Sinead; Li, Angela; Hayan, Sumar; Capanu, Marinela; Zheng, Junting; Riely, Gregory; Ginsberg, Michelle S

2017-04-01

Treatment with the ALK inhibitor crizotinib has been associated with complex renal cyst formation in patients with non-small cell lung cancer (NSCLC). Using patients treated with crizotinib, we aimed to evaluate the incidence of renal cyst formation, to identify risk factors for cyst formation and to provide a radiological description of cyst characteristics. Patients with ALK-positive NSCLC treated with crizotinib were retrospectively identified from an institutional database. Computed tomography (CT) imaging performed prior to and during crizotinib treatment was retrospectively reviewed to assess the size and complexity of pre-existing cysts, new cysts, and enlarging cysts. Demographic data including age, sex, ethnicity, smoking history and length of treatment were also recorded. Data from 60 patients with NSCLC treated with crizotinib at our institution between 6/5/2009 and 7/1/2015 were collected. 57 had CT imaging before and during treatment. Mean length of imaging follow-up was 18 months. 9 (16%) patients had cysts which enlarged or developed de novo during treatment. 2 (4%) patients developed complex renal cysts (1 of these patients also developed complex hepatic cysts). Female gender (p=0.008) and the presence of renal cysts on baseline scans (p=0.044) were significantly associated with cyst formation or growth. Renal cyst formation or growth occurred in 16% of crizotinib-treated patients. Women and those with pre-existing cysts were at greatest risk. Although the potential causal relationship between crizotinib use and renal cyst formation has yet to be fully defined, it is important for radiologists and clinicians to be aware of this finding. Copyright © 2017. Published by Elsevier B.V.

Induction of Female-to-Male Sex Change in Adult Zebrafish by Aromatase Inhibitor Treatment

NASA Astrophysics Data System (ADS)

Takatsu, Kanae; Miyaoku, Kaori; Roy, Shimi Rani; Murono, Yuki; Sago, Tomohiro; Itagaki, Hideyuki; Nakamura, Masaru; Tokumoto, Toshinobu

2013-12-01

This study investigated whether undifferentiated germ and/or somatic stem cells remain in the differentiated ovary of a species that does not undergo sex changes under natural conditions and retain their sexual plasticity. The effect of aromatase inhibitor (AI)-treatment on sexually mature female zebrafish was examined. A 5-month AI treatment caused retraction of the ovaries after which testes-like organs appeared, and cyst structures filled with spermatozoa-like cells were observed in sections of these tissues. Electron microscopic observations revealed that these cells appeared as large sperm heads without tails. Sperm formation was re-examined after changing the diet to an AI-free food. A large number of normal sperm were obtained after eight weeks, and no formation of ovarian tissue was observed. Artificial fertilization using sperm from the sex-changed females was successful. These results demonstrated that sex plasticity remains in the mature ovaries of this species.

Toll-like receptor 2 expression in refractory periapical lesions.

PubMed

Desai, S V; Love, R M; Rich, A M; Seymour, G J

2011-10-01

To investigate the expression of TLR2 in refractory periapical lesions. Refractory periapical lesion biopsies were histopathologically and clinically categorized into asymptomatic periapical granuloma (n=10), symptomatic periapical granuloma (n=10) or periapical cyst (n=10) and prepared for immunohistochemical staining using antibodies to TLR2, CD3 and CD19 or staining with methyl green pyronin. Sections were viewed under light microscopy and the presence or absence of the target cells was correlated with the histopathological and clinical data. Additionally, TLR2 expression was quantified by counting TLR(+) cells. Various mononuclear inflammatory cells in the bacteria-induced periapical lesions were reactive to TLR2 antibody, with many showing morphological similarities to lymphocytes and plasma cells. Lymphocytes were the most numerous cells in the inflammatory infiltrate. In refractory periapical granuloma, CD3(+) T cells were more numerous, whereas in periapical cysts, CD19(+) B cells were more numerous. There was a statistically significant (P<0.05) higher expression of TLR2 in symptomatic periapical granuloma than asymptomatic periapical granuloma or periapical cyst. The presence of TLR-expressing cells in periapical granulomas and cysts provides further evidence that periapical cysts are likely to be sustained by the immune system via reaction to bacterial antigens. © 2011 International Endodontic Journal.

Pulmonary complications of cystic echinococcosis in children in Uruguay.

PubMed

Sakamoto, Tsukasa; Gutierrez, Carmen

2005-08-01

Cystic echinococcal lesions surgically removed from 99 patients aged 1-15 years in Uruguay were histopathologically studied. The lesions were collected from the lungs, liver, peritoneum, omentum, pleura, ovary, appendix and perinephrium. All intact cysts were well-developed and unilocular. Pulmonary and hepatic fertile cysts in which protoscoleces were produced were in 75% and 47%, respectively, of all patients. Fertile cysts having many protoscoleces were in the lungs of a 1-year-old infant. Sixteen ruptured pulmonary cysts were found in the lungs of 13 patients and four ruptured hepatic cysts were found in the liver of three patients. Pulmonary complications were seen in patients having pulmonary echinococcal cysts. In lung tissue surrounding echinococcal cysts, pulmonary complications included chronic congestion, hemorrhage, bronchopneumonia, as well as interstitial pneumonia that included histological changes caused by bronchiolitis, organizing pneumonia and obstructive pneumonia. Liver tissue adjacent to echinococcal cysts showed atrophy of hepatic cells, proliferation of interstices, small focal hemorrhages, and infiltration of mononuclear cells. The present study shows that a close relationship exists between pulmonary echinococcosis and pneumonia. The term 'echinococcal pneumonia' is proposed for pneumonia accompanying pulmonary echinococcosis.

Analysis of the cytoskeleton organization and its possible functions in male earthworm germ-line cysts equipped with a cytophore.

PubMed

Małota, Karol; Świątek, Piotr

2016-10-01

We studied the organization of F-actin and the microtubular cytoskeleton in male germ-line cysts in the seminal vesicles of the earthworm Dendrobaena veneta using light, fluorescent and electron microscopy along with both chemically fixed tissue and life cell imaging. Additionally, in order to follow the functioning of the cytoskeleton, we incubated the cysts in colchicine, nocodazole, cytochalasin D and latrunculin A. The male germ-line cells of D. veneta are interconnected via stable intercellular bridges (IB), and form syncytial cysts. Each germ cell has only one IB that connects it to the anuclear central cytoplasmic mass, the cytophore. During the studies, we analyzed the cytoskeleton in spermatogonial, spermatocytic and spermatid cysts. F-actin was detected in the cortical cytoplasm and forms distinct rings in the IBs. The arrangement of the microtubules changed dynamically during spermatogenesis. The microtubules are distributed evenly in whole spermatogonial and spermatocytic cysts; however, they primarily accumulate within the IBs in spermatogonia. In early spermatids, microtubules pass through the IBs and are present in whole cysts. During spermatid elongation, the microtubules form a manchette while they are absent in the cytophore and in the IBs. Use of cytoskeletal drugs did not alter the general morphology of the cysts. Detectable effects-the occurrence of nuclei in the late spermatids and manchette fragments in the cytophore-were observed only after incubation in nocodazole. Our results suggest that the microtubules are responsible for cytoplasmic/organelle transfer between the germ cells and the cytophore during spermatogenesis and for the positioning of the spermatid nuclei.

Nuclear inheritance and genetic exchange without meiosis in the binucleate parasite Giardia intestinalis

PubMed Central

Carpenter, Meredith L.; Assaf, Zoe June; Gourguechon, Stéphane; Cande, W. Zacheus

2012-01-01

The protozoan parasite Giardia intestinalis (also known as Giardia lamblia) is a major waterborne pathogen. During its life cycle, Giardia alternates between the actively growing trophozoite, which has two diploid nuclei with low levels of allelic heterozygosity, and the infectious cyst, which has four nuclei and a tough outer wall. Although the formation of the cyst wall has been studied extensively, we still lack basic knowledge about many fundamental aspects of the cyst, including the sources of the four nuclei and their distribution during the transformation from cyst into trophozoite. In this study, we tracked the identities of the nuclei in the trophozoite and cyst using integrated nuclear markers and immunofluorescence staining. We demonstrate that the cyst is formed from a single trophozoite by a mitotic division without cytokinesis and not by the fusion of two trophozoites. During excystation, the cell completes cytokinesis to form two daughter trophozoites. The non-identical nuclear pairs derived from the parent trophozoite remain associated in the cyst and are distributed to daughter cells during excystation as pairs. Thus, nuclear sorting (such that each daughter cell receives a pair of identical nuclei) does not appear to be a mechanism by which Giardia reduces heterozygosity between its nuclei. Rather, we show that the cyst nuclei exchange chromosomal genetic material, perhaps as a way to reduce heterozygosity in the absence of meiosis and sex, which have not been described in Giardia. These results shed light on fundamental aspects of the Giardia life cycle and have implications for our understanding of the population genetics and cell biology of this binucleate parasite. PMID:22366460

Analysis of silver stained nucleolar organizing regions in odontogenic cysts and tumors.

PubMed

Prasanna, Md; Charan, Cr; Reddy Ealla, Kranti Kiran; Surekha, V; Kulkarni, Ganesh; Gokavarapu, Sandhya

2014-09-01

The present study aimed to investigate the probable differences in cell proliferation index of odontogenic cysts and tumors by means of a comparative silver stained nucleolar organizing region (AgNOR) quantification. This descriptive cross-sectional study was done on archival paraffin blocks (n = 62), consisting of 10 odontogenic keratocysts, 10 dentigerous cysts, 10 radicular cysts, 10 conventional ameloblastomas, 10 adenomatoid odontogenic tumors, 10 calcifying epithelial odontogenic tumors and 2 ameloblasic carcinomas. The mean AgNOR count of odontogenic cysts was 1.709 and the benign odontogenic tumors was 1.862. Highest AgNOR count was recorded in odontogenic keratocyst and lowest was seen in radicular cyst. Statistically significant difference in AgNOR counts of ameloblastoma and adenomatoid odontogenic tumor, amelobalastoma and calcifying epithelial odontogenic tumor, benign odontogenic tumors and ameloblastic carcinoma were seen. AgNORs in ameloblastic carcinoma were more in number and more widely spread. AgNOR technique may be considered a good indicator of cell proliferation in odontogenic cysts and tumors.

Analysis of silver stained nucleolar organizing regions in odontogenic cysts and tumors

PubMed Central

Prasanna, MD; Charan, CR; Reddy Ealla, Kranti Kiran; Surekha, V; Kulkarni, Ganesh; Gokavarapu, Sandhya

2014-01-01

Objective: The present study aimed to investigate the probable differences in cell proliferation index of odontogenic cysts and tumors by means of a comparative silver stained nucleolar organizing region (AgNOR) quantification. Study Design: This descriptive cross-sectional study was done on archival paraffin blocks (n = 62), consisting of 10 odontogenic keratocysts, 10 dentigerous cysts, 10 radicular cysts, 10 conventional ameloblastomas, 10 adenomatoid odontogenic tumors, 10 calcifying epithelial odontogenic tumors and 2 ameloblasic carcinomas. Results: The mean AgNOR count of odontogenic cysts was 1.709 and the benign odontogenic tumors was 1.862. Highest AgNOR count was recorded in odontogenic keratocyst and lowest was seen in radicular cyst. Statistically significant difference in AgNOR counts of ameloblastoma and adenomatoid odontogenic tumor, amelobalastoma and calcifying epithelial odontogenic tumor, benign odontogenic tumors and ameloblastic carcinoma were seen. AgNORs in ameloblastic carcinoma were more in number and more widely spread. Conclusion: AgNOR technique may be considered a good indicator of cell proliferation in odontogenic cysts and tumors. PMID:25364178

Naturally induced secretions of the potato cyst nematode co-stimulate the proliferation of both tobacco leaf protoplasts and human peripheral blood mononuclear cells.

PubMed

Goverse, A; Rouppe van der Voort, J; Roppe van der Voort, C; Kavelaars, A; Smant, G; Schots, A; Bakker, J; Helder, J

1999-10-01

Naturally induced secretions from infective juveniles of the potato cyst nematode Globodera rostochiensis co-stimulate the proliferation of tobacco leaf protoplasts in the presence of the synthetic phytohormones alpha-naphthaleneacetic acid (NAA) and 6-benzylaminopurine (BAP). With the use of a protoplast-based bioassay, a low-molecular-weight peptide(s) (< 3 kDa) was shown to be responsible for the observed effect. This mitogenic oligopeptide(s) is functionally dissimilar to auxin and cytokinin and, in addition, it does not change the sensitivity of the protoplasts toward these phytohormones. In combination with the mitogen phytohemagglutinin (PHA), cyst nematode secretions also co-stimulated mitogenesis in human peripheral blood mononuclear cells (PBMC). The stimulation of plant cells isolated from nontarget tissue--these nematodes normally invade the roots of potato plants--suggests the activation of a general signal transduction mechanism(s) by an oligopeptide(s) secreted by the nematode. Whether a similar oligopeptide-induced mechanism underlies human PBMC activation remains to be investigated. Reactivation of the cell cycle is a crucial event in feeding cell formation by cyst nematodes. The secretion of a mitogenic low-molecular-weight peptide(s) by infective juveniles of the potato cyst nematode could contribute to the redifferentiation of plant cells into such a feeding cell.

Dual lumbar bronchogenic and arachnoid cyst presenting with sciatica and left foot drop.

PubMed

Candy, Nicholas; Young, Adam; Devadass, Abel; Dean, Andrew; McMillen, Jason; Trivedi, Rikin

2017-10-01

Spinal bronchogenic cysts are rare findings, with only four cases of lumbar bronchogenic cysts reported in the literature. All of these bronchogenic cysts involved the conus medullaris. We present the first case of a lumbar bronchogenic cyst and arachnoid cyst arising from the cauda equina in a 68-year-old male. Uniquely, this bronchogenic cyst also contained components of an arachnoid cyst. Magnetic resonance imaging (MRI) demonstrated a compressive cystic lesion at the level of the L3 vertebra splaying the cauda equina. An L3/L4 laminectomy was performed with marsupialisation of the cyst. Histological examination revealed pseudostratified ciliated columnar epithelium confirming the diagnosis of a bronchogenic cyst, as well as a pleated fibrovascular tissue lined by sparsely spaced small monomorphic arachnoidal cells, indicating an arachnoid cyst. We demonstrate that bronchogenic cysts can be successfully treated with marsupialisation.

Expression of Vascular Endothelial Growth Factor in Odontogenic Cysts: Is There Any Impression on Clinical Outcome?

PubMed

Sadri, Donia; Farhadi, Sareh; Shahabi, Zahra; Sarshar, Samaneh

2016-01-01

The recent scientific reports have shown that angiogenesis can affect biological behavior of pathologic lesions. Regarding unique clinical outcome of Odontogenic keratocyst (OKC), the present study was aimed to compare angiogenesis in Odontogenic keratocyst and Dentigerous cyst (DC). In this experimental study, tissue sections of 46 samples of OKC and DC were stained through immunohistochemical method using Vascular Endothelial Growth Factor (VEGF) antibody. VEGF expression was evaluated in epithelial cells, fibroblasts and endothelial cells. The average percentage of stained cells in any samples was categorized to 3 groups as follows: SCORE 0: 10% of cells or less are positive. SCORE 1: 10 to 50% of cells are positive. SCORE 2: more than 50% of cells are positive. Mann-U-Whitney, T-test and chi-square was used for statistical analysis. The average of VEGF expression in 24 samples of DC was 20.2% and in 22 samples of OKC was 52.6%, respectively. The average of VEGF expression in these two cysts had statistical significant differences. (PV= 0.045). There was significant statistical differences between two cysts in the terms of VEGF SCORE (PV= 0.000). OKC samples had significantly higher SCORE for the purpose of VEGF incidence than DC. Also, there were no differences between VEGF expression in epithelial cells of two cysts (PV= 0.268) there were significant statistical differences between two cysts in terms of endothelial cell staining. The endothelial cell staining was significantly higher in OKC than DC (PV= 0.037%). Regarding higher expression of Vascular Endothelial Growth factor in OKC than DC, it seems that angiogenesis may have great impression on clinical outcome of OKC.

Tissue-engineered skin preserving the potential of epithelial cells to differentiate into hair after grafting.

PubMed

Larouche, Danielle; Cuffley, Kristine; Paquet, Claudie; Germain, Lucie

2011-03-01

The aim of this study was to evaluate whether tissue-engineered skin produced in vitro was able to sustain growth of hair follicles in vitro and after grafting. Different tissues were designed. Dissociated newborn mouse keratinocytes or newborn mouse hair buds (HBs) were added onto dermal constructs consisting of a tissue-engineered cell-derived matrix elaborated from either newborn mouse or adult human fibroblasts cultured with ascorbic acid. After 7-21 days of maturation at the air-liquid interface, no hair was noticed in vitro. Epidermal differentiation was observed in all tissue-engineered skin. However, human fibroblast-derived tissue-engineered dermis (hD) promoted a thicker epidermis than mouse fibroblast-derived tissue-engineered dermis (mD). In association with mD, HBs developed epithelial cyst-like inclusions presenting outer root sheath-like attributes. In contrast, epidermoid cyst-like inclusions lined by a stratified squamous epithelium were present in tissues composed of HBs and hD. After grafting, pilo-sebaceous units formed and hair grew in skin elaborated from HBs cultured 10-26 days submerged in culture medium in association with mD. However, the number of normal hair follicles decreased with longer culture time. This hair-forming capacity after grafting was not observed in tissues composed of hD overlaid with HBs. These results demonstrate that epithelial stem cells can be kept in vitro in a permissive tissue-engineered dermal environment without losing their potential to induce hair growth after grafting.

Immunomodulatory activity of interleukin-27 in human chronic periapical diseases

PubMed Central

Li, Juan; Wang, Rong; Huang, Shi-Guang

2017-01-01

This study aims to observe expression of IL-27 on different cells in periapical tissues of different types of human chronic periapical diseases. Periapical tissue specimens of 60 donors, including healthy control (n=20), periapical granuloma group (n=20) and radicular cysts group (n=20), were fixed in 10% buffered formalin, stained with hematoxylin and eosin for histopathology. Then specimens were stained with double- immuno-fluorescence assay for identification of IL-27-tryptase (mast cells, MCs), IL-27-CD14 (mononuclear phagocyte cells, MPs) and IL-27-CD31 (endothelial cells, ECs) double-positive cells in periapical tissues. The results indicated that compared with healthy control, the densities (cells/mm2) of IL-27-tryptase, IL-27-CD14 and IL-27-CD31 double-positive cells were significantly increased in human chronic periapical diseases (periapical granuloma group and radicular cysts group) (P<0.001). The density of IL-27-tryptase double positive cells in radicular cysts group was significantly higher than those in periapical granuloma group (P<0.001). Densities of IL-27-CD14 and IL-27-CD31 double-positive cells in periapical granuloma group had no significant difference with those in radicular cysts group (P=0.170 and 0.138, respectively). IL-27-CD14 double positive cells density achieved to peak among three cell groups in radicular cysts groups. In conclusion, IL-27 expressed in MCs, MPs and ECs of human chronic periapical diseases with different degrees. IL-27-tryptase double-positive cells may participate in pathogenic mechanism of chronic periapical diseases, especially for formation of fibrous in periapical cysts. IL-27-CD14 and IL-27-CD31 double-positive cells may participate in immunologic response to resist periapical infection, and they may play an dual role in pathogenesis and localization of periapical diseases. PMID:28386371

Malignant changes developing from odontogenic cysts: A systematic review.

PubMed

Borrás-Ferreres, Jordi; Sánchez-Torres, Alba; Gay-Escoda, Cosme

2016-12-01

The aim of this study was to systematically review scientific literature in orderto describe the characteristics and prognosis of malignant entities developing from odontogenic cysts. A search in Pubmed (MEDLINE) and Cochrane databases was conducted. The inclusion criteria were articles published in English related to the malignisation of odontogenic cysts in humans. The exclusion criteria were articles that do not specify the type of odontogenic cyst, malignisation of parakeratinised keratocysts, the presence of an ameloblastic carcinoma and metastasis from distant primary tumours. The selected articles were classified according to Strength of Recommendation Taxonomy criteria. Statistical analysis of the data was carried out using statistical package software SPSS version 22.0. From the 1,237 articles initially obtained, the authors included 3 case series and 45 case reports in the end. Descriptive analysis showed that men have a disposition for malignisation from odontogenic cysts and they frequently appear at the posterior mandible, with pain and swelling being the most frequent signs and symptoms. Follicular cysts were the entities that underwent the most malignant changes with well differentiated squamous cell carcinomas being the most prevalent type of malignancy. The real prognosis of this malignancy is not known because of the heterogeneity of available studies. Key words: Odontogenic cysts, squamous cell carcinoma, neoplastic cell transformation, oral cancer.

Midline cystic malformations of the brain: imaging diagnosis and classification based on embryologic analysis.

PubMed

Utsunomiya, Hidetsuna; Yamashita, Shinichi; Takano, Koichi; Ueda, Yukiyo; Fujii, Akira

2006-07-01

This article describes a classification and imaging diagnosis of intracranial midline cystic malformations based on neuroembryologic analysis. Midline cystic malformations are classified into two categories from an embryologic point of view. In one category, the cyst represents expansion of the roof plate of the brain vesicle, and in the other the cyst consists of extraaxial structures such as an arachnoid membrane or migrating ependymal cells. Infratentorial cysts, such as the Dandy-Walker cyst or Blake's pouch cyst, and supratentorial cysts, such as a communicating interhemispheric cyst with callosal agenesis or a dorsal cyst with holoprosencephaly, are included in the first category. Infratentorial arachnoid cavities, such as the arachnoid cyst, arachnoid pouch, and mega cisterna magna, are in the second category. Noncommunicating interhemispheric cysts, such as interhemispheric arachnoid cyst or ependymal cyst, with callosal agenesis are also in the second category. A careful review of embryologic development is essential for understanding these midline cysts and for making a more accurate radiologic diagnosis.

Three-Dimensional Ultrastructural Study of Oil and Astaxanthin Accumulation during Encystment in the Green Alga Haematococcus pluvialis

PubMed Central

Matsuura, Hazuki; Nango, Nobuhito; Hirata, Aiko; Kawano, Shigeyuki

2013-01-01

Haematococcus pluvialis is a freshwater species of green algae and is well known for its accumulation of the strong antioxidant astaxanthin, which is used in aquaculture, various pharmaceuticals, and cosmetics. High levels of astaxanthin are present in cysts, which rapidly accumulate when the environmental conditions become unfavorable for normal cell growth. It is not understood, however, how accumulation of high levels of astaxanthin, which is soluble in oil, becomes possible during encystment. Here, we performed ultrastructural 3D reconstruction based on over 350 serial sections per cell to visualize the dynamics of astaxanthin accumulation and subcellular changes during the encystment of H. pluvialis. This study showcases the marked changes in subcellular elements, such as chloroplast degeneration, in the transition from green coccoid cells to red cyst cells during encystment. In green coccoid cells, chloroplasts accounted for 41.7% of the total cell volume, whereas the relative volume of astaxanthin was very low (0.2%). In contrast, oil droplets containing astaxanthin predominated in cyst cells (52.2%), in which the total chloroplast volume was markedly decreased (9.7%). Volumetric observations also demonstrated that the relative volumes of the cell wall, starch grains, pyrenoids, mitochondria, the Golgi apparatus, and the nucleus in a cyst cell are smaller than those in green coccid cells. Our data indicated that chloroplasts are degraded, resulting in a net-like morphology, but do not completely disappear, even at the red cyst stage. PMID:23326471

Apical Cyst Theory: a Missing Link.

PubMed

Huang, George T-J

2010-10-05

The mechanism of the formation of apical cyst has been elusive. Several theories have long been proposed and discussed speculating how an apical cyst is developed and formed in the jaw bone resulting from endododontic infection. Two popular theories are the nutritional deficiency theory and the abscess theory. The nutritional deficiency theory assumes that the over proliferated epithelial cells will form a ball mass such that the cells in the center of the mass will be deprived of nutrition. The abscess theory postulates that when an abscess cavity is formed in connective tissue, epithelial cells proliferate and line the preexisting cavity because of their inherent tendency to cover exposed connective tissue surfaces. Based on the nature of epithelial cells and the epithelium, nutritional theory is a fairy tale, while abscess theory at best just indicates that abscess may be one of the factors that allows the stratified epithelium to form but not to explain a mechanism that makes the cyst to form. Apical cyst formation is the result of proliferation of resting epithelial cells, due to inflammation, to a sufficient number such that they are able to form a polarized and stratified epithelial lining against dead tissues or foreign materials. These stratified epithelial lining expands along the dead tissue or foreign materials and eventually wrap around them as a spherical sac, i.e. a cyst. The space in the sac is considered the external environment separating the internal (tissue) environment - the natural function of epithelium. This theory may be tested by introducing a biodegradable device able to slowly release epithelial cell mitogens in an in vivo environment implanted with epithelial cells next to a foreign object. This will allow the cells to continuously proliferate which may form a cystic sac wrapping around the foreign object.

Apical Cyst Theory: a Missing Link

PubMed Central

Huang, George T.-J.

2012-01-01

Introduction The mechanism of the formation of apical cyst has been elusive. Several theories have long been proposed and discussed speculating how an apical cyst is developed and formed in the jaw bone resulting from endododontic infection. Two popular theories are the nutritional deficiency theory and the abscess theory. The nutritional deficiency theory assumes that the over proliferated epithelial cells will form a ball mass such that the cells in the center of the mass will be deprived of nutrition. The abscess theory postulates that when an abscess cavity is formed in connective tissue, epithelial cells proliferate and line the preexisting cavity because of their inherent tendency to cover exposed connective tissue surfaces. Based on the nature of epithelial cells and the epithelium, nutritional theory is a fairy tale, while abscess theory at best just indicates that abscess may be one of the factors that allows the stratified epithelium to form but not to explain a mechanism that makes the cyst to form. The hypothesis Apical cyst formation is the result of proliferation of resting epithelial cells, due to inflammation, to a sufficient number such that they are able to form a polarized and stratified epithelial lining against dead tissues or foreign materials. These stratified epithelial lining expands along the dead tissue or foreign materials and eventually wrap around them as a spherical sac, i.e. a cyst. The space in the sac is considered the external environment separating the internal (tissue) environment – the natural function of epithelium. Evaluation of the hypothesis This theory may be tested by introducing a biodegradable device able to slowly release epithelial cell mitogens in an in vivo environment implanted with epithelial cells next to a foreign object. This will allow the cells to continuously proliferate which may form a cystic sac wrapping around the foreign object. PMID:25346864

Quantification and Localization of Mast Cells in Periapical Lesions

PubMed Central

Mahita, VN; Manjunatha, BS; Shah, R; Astekar, M; Purohit, S; Kovvuru, S

2015-01-01

Background: Periapical lesions occur in response to chronic irritation in periapical tissue, generally resulting from an infected root canal. Specific etiological agents of induction, participating cell population and growth factors associated with maintenance and resolution of periapical lesions are incompletely understood. Among the cells found in periapical lesions, mast cells have been implicated in the inflammatory mechanism. Aim: Quantifications and the possible role played by mast cells in the periapical granuloma and radicular cyst. Hence, this study is to emphasize the presence (localization) and quantification of mast cells in periapical granuloma and radicular cyst. Materials and Methods: A total of 30 cases and out of which 15 of periapical granuloma and 15 radicular cyst, each along with the case details from the previously diagnosed cases in the department of oral pathology were selected for the study. The gender distribution showed male 8 (53.3%) and females 7 (46.7%) in periapical granuloma cases and male 10 (66.7%) and females 5 (33.3%) in radicular cyst cases. The statistical analysis used was unpaired t-test. Results: Mean mast cell count in periapical granuloma subepithelial and deeper connective tissue, was 12.40 (0.99%) and 7.13 (0.83%), respectively. The mean mast cell counts in subepithelial and deeper connective tissue of radicular cyst were 17.64 (1.59%) and 12.06 (1.33%) respectively, which was statistically significant. No statistical significant difference was noted among males and females. Conclusion: Mast cells were more in number in radicular cyst. Based on the concept that mast cells play a critical role in the induction of inflammation, it is logical to use therapeutic agents to alter mast cell function and secretion, to thwart inflammation at its earliest phases. These findings may suggest the possible role of mast cells in the pathogenesis of periapical lesions. PMID:25861530

In situ dynamics of cyst and vegetative cell populations of the toxic dinoflagellate Alexandrium catenella in Ago Bay, central Japan

PubMed Central

Ishikawa, Akira; Hattori, Mayuko; Ishii, Ken-Ichiro; Kulis, David M.; Anderson, Donald M.; Imai, Ichiro

2014-01-01

Temporal changes in the in situ germination flux of cysts and the abundance of vegetative cells of the toxic dinoflagellate Alexandrium catenella were investigated in Ago Bay, central Japan from July 2003 to December 2004. The in situ germination flux (cells m−2 day−1) was measured using ‘plankton emergence trap/chambers (PET chambers)’. Germination of the cysts in the sediments occurred continuously during the study, ranging from 52 to 1753 cells m−2 day−1, with no temporal trend. This germination pattern appeared to be promoted by a short mandatory dormancy period for newly formed cysts coupled with a broad temperature window for germination. For the vegetative populations, high abundances (>105 cells m−2) were recorded in the water column from spring to summer and from autumn to early winter. The size of the vegetative populations did not correlate with the cyst germination flux but rather larger vegetative populations were often observed when the water temperature was around 20°C, indicating that bloom development was mainly regulated by the temperature. Nonetheless, the continuous germination pattern of A. catenella is advantageous enabling the germinated cells to immediately exploit favorable bloom conditions. PMID:25221373

The potential for dispersal of microalgal resting cysts by migratory birds.

PubMed

Tesson, Sylvie Vm; Weißbach, Astrid; Kremp, Anke; Lindström, Åke; Rengefors, Karin

2018-06-11

Most microalgal species are geographically widespread, but little is known about how they are dispersed. One potential mechanism for long-distance dispersal is through birds, which may transport cells internally (endozoochory) and deposit them during, or in-between, their migratory stopovers. We hypothesize that dinoflagellates, in particular resting stages, can tolerate bird digestion; that bird temperature, acidity, and retention time negatively affect dinoflagellate viability; and that recovered cysts can germinate after passage through the birds' gut, contributing to species-specific dispersal of the dinoflagellates across scales. Tolerance of two dinoflagellate species (Peridiniopsis borgei, a warm-water species and Apocalathium malmogiense, a cold-water species) to Mallard gut passage was investigated using in vitro experiments simulating the gizzard and caeca conditions. The effect of in vitro digestion and retention time on cell integrity, cell viability and germination capacity of the dinoflagellate species was examined targeting both their vegetative and resting stages. Resting stages (cysts) of both species were able to survive simulated bird gut passage, even if their survival rate and germination were negatively affected by exposure to acidic condition and bird internal temperature. Cysts of A. malmogiense were more sensitive than P. borgei to treatments and to the presence of digestive enzymes. Vegetative cells did not survive conditions of bird internal temperature and formed pellicle cysts when exposed to gizzard-like acid conditions. We show that dinoflagellate resting cysts serve as dispersal propagules through migratory birds. Assuming a retention time of viable cysts of 2-12 h to duck stomach conditions, cysts could be dispersed 150-800 km and beyond. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Immunohistochemical evaluation of inducible nitric oxide synthase in the epithelial lining of odontogenic cysts: A qualitative and quantitative analysis.

PubMed

Akshatha, B K; Karuppiah, Karpagaselvi; Manjunath, G S; Kumarswamy, Jayalakshmi; Papaiah, Lokesh; Rao, Jyothi

2017-01-01

The three common odontogenic cysts include radicular cysts (RCs), dentigerous cysts (DCs), and odontogenic keratocysts (OKCs). Among these 3 cysts, OKC is recently been classified as benign keratocystic odontogenic tumor attributing to its aggressive behavior, recurrence rate, and malignant potential. The present study involved qualitative and quantitative analysis of inducible nitric oxide synthase (iNOS) expression in epithelial lining of RCs, DCs, and OKCs, compare iNOS expression in epithelial linings of all the 3 cysts and determined overexpression of iNOS in OKCs which might contribute to its aggressive behavior and malignant potential. The present study is to investigate the role of iNOS in the pathogenesis of OKCs, DCs, and RCs by evaluating the iNOS expression in the epithelial lining of these cysts. Analysis of iNOS expression in epithelial lining cells of 20 RCs, 20 DCs, and 20 OKCs using immunohistochemistry done. The percentage of positive cells and intensity of stain was assessed and compared among all the 3 cysts using contingency coefficient. Kappa statistics for the two observers were computed for finding interobserver agreement. The percentage of iNOS-positive cells was found to be remarkably high in OKCs (12/20) -57.1% as compared to RCs (6/20) - 28.6% and DCs (3/20) - 14.3%. The interobserver agreement for iNOS-positive percentage cells was arrived with kappa values with OKCs → Statistically significant ( P > 0.000), RCs → statistically significant ( P > 0.001) with no significant values for DCs. No statistical difference exists among 3 study samples in regard to the intensity of staining with iNOS. Increased iNOS expression in OKCs may contribute to bone resorption and accumulation of wild-type p53, hence, making OKCs more aggressive.

Cyst-theca relationship of the arctic dinoflagellate cyst Islandinium minutum (Dinophyceae) and phylogenetic position based on SSU rDNA and LSU rDNA.

PubMed

Potvin, Éric; Rochon, André; Lovejoy, Connie

2013-10-01

Round brown spiny cysts constitute a morphological group common in high latitude dinoflagellate cyst assemblages. The dinoflagellate cyst Islandinium minutum (Harland et Reid) Head, Harland et Matthiessen is the main paleoecological indicator of seasonal sea-ice cover in the Arctic. Despite the importance of this cyst in paleoceanographical studies, its biological affinity has so far been unknown. The biological affinity of the species I. minutum and its phylogenetic position based on the small subunit ribosomal RNA gene (SSU rDNA) and the large subunit ribosomal RNA gene (LSU rDNA) were established from cyst incubation experiments in controlled conditions, optical and scanning electron microscopy, and single-cell PCR. The thecal motile cell obtained was undescribed. Although the motile cell was similar to Archaeperidinium minutum (Kofoid) Jörgensen, the motile cell of I. minutum lacked a transitional plate in the cingular series, which is present in Archaeperidinium spp. Islandinium minutum and Archaeperidinium spp. were paraphyletic in all phylogenetic analyses. Furthermore, Protoperidinium tricingulatum, which also lacks a transitional plate, was closely related to I. minutum and transfered to the genus Islandinium. Based on available data, it is clear that Islandinium is distinct from Archaeperidinium. Therefore, we considered Islandinium Head, Harland et Matthiessen as a non-fossil genus and emend its description, as well as the species I. minutum. This is the first description of a cyst-theca relationship and the first study that reports molecular data based on SSU rDNA and LSU rDNA on a species assigned to the genus Islandinium. © 2013 Phycological Society of America.

Is Routine Pathologic Evaluation of Sebaceous Cysts Necessary?: A 15-Year Retrospective Review of a Single Institution.

PubMed

Gargya, Vipul; Lucas, Heather D; Wendel Spiczka, Amy J; Mahabir, Raman Chaos

2017-02-01

A question arose in our practice of whether all cysts considered sebaceous should be sent for pathologic evaluation. To address this controversial topic, we performed a retrospective study of our single institution's histopathology database. A natural language search of the CoPath database across the institution was undertaken using the diagnosis of sebaceous cyst, epidermal cyst, epidermoid cyst, epithelial cyst, infundibular cyst, pilar cyst, trichilemmal cyst, and steatocystoma. A surgical pathologic review of all specimens with one of these preexcision diagnoses was included in the 15-year retrospective study of 1998 to 2013. All slides were confirmed to have undergone histopathologic review, and the preexcision diagnoses were compared with the postexcision diagnoses. Chart review was undertaken in instances of a diagnosis of malignancy. A total of 13,746 samples were identified. Forty-eight specimens had histopathologic diagnosis of malignancy, for an incidence of 0.3% and with the most common malignancy being squamous cell carcinoma. Chart review showed that for all cases, the surgeons reported uncertainty with regard to the diagnosis because of history or physical characteristics, or both. In addition, a comprehensive literature review showed results consistent with our data and illustrated 19 cases during the past 10 years in which most of the findings were squamous cell carcinoma. We propose the recommendation that routine pathologic evaluation of sebaceous cysts is necessary only when clinical suspicion exists.

Mechanical Characterization of Microengineered Epithelial Cysts by Using Atomic Force Microscopy.

PubMed

Shen, Yusheng; Guan, Dongshi; Serien, Daniela; Takeuchi, Shoji; Tong, Penger; Yobas, Levent; Huang, Pingbo

2017-01-24

Most organs contain interconnected tubular tissues that are one-cell-thick, polarized epithelial monolayers enclosing a fluid-filled lumen. Such tissue organization plays crucial roles in developmental and normal physiology, and the proper functioning of these tissues depends on their regulation by complex biochemical perturbations and equally important, but poorly understood, mechanical perturbations. In this study, by combining micropatterning techniques and atomic force microscopy, we developed a simple in vitro experimental platform for characterizing the mechanical properties of the MDCK II cyst, the simplest model of lumen-enclosing epithelial monolayers. By using this platform, we estimated the elasticity of the cyst monolayer and showed that the presence of a luminal space influences cyst mechanics substantially, which could be attributed to polarization and tissue-level coordination. More interestingly, the results from force-relaxation experiments showed that the cysts also displayed tissue-level poroelastic characteristics that differed slightly from those of single cells. Our study provides the first quantitative findings, to our knowledge, on the tissue-level mechanics of well-polarized epithelial cysts and offers new insights into the interplay between cyst mechanics and cyst physiology. Moreover, our simple platform is a potentially useful tool for enhancing the current understanding of cyst mechanics in health and disease. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

A CheR/CheB fusion protein is involved in cyst cell development and chemotaxis in Azospirillum brasilense Sp7.

PubMed

Wu, Lixian; Cui, Yanhua; Hong, Yuanyuan; Chen, Sanfeng

2011-12-20

We here report the sequence and functional analysis of cstB of Azospirillum brasilense Sp7. The predicted cstB contains C-terminal two PAS domains and N-terminal part which has similarity with CheB-CheR fusion protein. cstB mutants had reduced swarming ability compared to that of A. brasilense wild-type strain, implying that cstB was involved in chemotaxis in A. brasilense. A microscopic analysis revealed that cstB mutants developed mature cyst cells more quickly than wild type, indicating that cstB is involved in cyst formation. cstB mutants were affected in colony morphology and the production of exopolysaccharides (EPS) which are essential for A. brasilense cells to differentiate into cyst-like forms. These observations suggested that cstB was a multi-effector involved in cyst development and chemotaxis in A. brasilense. Copyright © 2010 Elsevier GmbH. All rights reserved.

The novel cyst nematode effector protein 19C07 interacts with the Arabidopsis auxin influx transporter LAX3 to control feeding site development

USDA-ARS?s Scientific Manuscript database

Plant-parasitic cyst nematodes penetrate plant roots and transform cells near the vasculature into specialized feeding sites, called syncytia. Syncytia form by incorporating neighboring cells into a single fused cell by cell wall dissolution. This process is initiated via injection of esophageal gla...

Mitochondrial Abnormality Facilitates Cyst Formation in Autosomal Dominant Polycystic Kidney Disease

PubMed Central

Ishimoto, Yu; Yoshihara, Daisuke; Kugita, Masanori; Nagao, Shizuko; Shimizu, Akira; Takeda, Norihiko; Wake, Masaki; Honda, Kenjiro; Zhou, Jing

2017-01-01

ABSTRACT Autosomal dominant polycystic kidney disease (ADPKD) constitutes the most inherited kidney disease. Mutations in the PKD1 and PKD2 genes, encoding the polycystin 1 and polycystin 2 Ca2+ ion channels, respectively, result in tubular epithelial cell-derived renal cysts. Recent clinical studies demonstrate oxidative stress to be present early in ADPKD. Mitochondria comprise the primary reactive oxygen species source and also their main effector target; however, the pathophysiological role of mitochondria in ADPKD remains uncharacterized. To clarify this function, we examined the mitochondria of cyst-lining cells in ADPKD model mice (Ksp-Cre PKD1flox/flox) and rats (Han:SPRD Cy/+), demonstrating obvious tubular cell morphological abnormalities. Notably, the mitochondrial DNA copy number and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) expression were decreased in ADPKD model animal kidneys, with PGC-1α expression inversely correlated with oxidative stress levels. Consistent with these findings, human ADPKD cyst-derived cells with heterozygous and homozygous PKD1 mutation exhibited morphological and functional abnormalities, including increased mitochondrial superoxide. Furthermore, PGC-1α expression was suppressed by decreased intracellular Ca2+ levels via calcineurin, p38 mitogen-activated protein kinase (MAPK), and nitric oxide synthase deactivation. Moreover, the mitochondrion-specific antioxidant MitoQuinone (MitoQ) reduced intracellular superoxide and inhibited cyst epithelial cell proliferation through extracellular signal-related kinase/MAPK inactivation. Collectively, these results indicate that mitochondrial abnormalities facilitate cyst formation in ADPKD. PMID:28993480

Endometriosis-associated hydrocele of the canal of Nuck with immunohistochemical confirmation: a case report.

PubMed

Okoshi, Kae; Mizumoto, Masaki; Kinoshita, Koichi

2017-12-21

The canal of Nuck is an embryological vestige of the processus vaginalis, and presents a potential site for endometriosis seeding. Hydroceles in this region are a rare cause of inguinal swelling in females. In addition, endometriosis localized to the canal of Nuck is exceedingly rare. A 44-year-old Japanese woman presented with a painful mass overlying her right pubis. She underwent surgery to completely excise the mass. During surgery, division of the external oblique aponeurosis revealed a cyst that occupied the inguinal canal and it adhered to the transverse fascia, inguinal ligament, and pubic bone. The cyst was dissected from the round ligament, and the defect in the internal inguinal ring was repaired and reinforced with mesh. On macroscopic examination, the cyst had a heterogeneous fibrous aspect with dark brown inclusions. Microscopic examination revealed that the cyst was tortuous, lined by mesothelial-like cells, and accompanied by partial subcapsular hemorrhage. Endometrium-like tissue was observed in the cystic wall. Immunohistochemical staining for podoplanin confirmed the mesothelial origin of the cyst-lining cells. The epithelial cells and stromal cells were positive for estrogen receptors. In this case of an endometriosis-associated hydrocele of the canal of Nuck, the mesothelial origin of the cyst-lining cells and endometriosis were confirmed by positive immunohistochemical staining for podoplanin and estrogen receptors, respectively. We determined that hydrocele resection and reinforcement of the anterior inguinal canal wall (if necessary) are appropriate treatments for this condition.

Angiogenesis in mucous retention cyst: a human in vivo-like model of endothelial cell differentiation in mucous substrate.

PubMed

Swelam, Wael; Ida-Yonemochi, Hiroko; Saku, Takashi

2005-01-01

Mucous retention cysts contain a mucous pool in the lumina, in which pure angiogenic processes are occasionally observed. By using this unique human material, our aim was to understand the in vivo angiogenic process. Fifteen surgical tissue samples of mucous retention cysts of the lip were examined for expression of vascular endothelial markers and extracellular matrix molecules by immunohistochemistry and in situ hybridization (ISH). Endothelial cells forming new vascular channels showed immunopositivities for CD31, CD34, vascular endothelial growth factor (VEGF), and von Willebrand factor (vWF). These newly formed capillaries were surrounded by tenascin-positive matrices and further by a dense infiltration of CD68-positive cells with foamy to epitheloid appearances. Some of these cells were simultaneously positive for CD34, VEGF, and one of its receptors, Flk-1, and they showed definite mRNA as well as protein signals for tenascin. In addition, these cells often tended to be aligned, which suggested tubule formation. The results suggest that monocyte/macrophage lineage cells are a major source for endothelial cells at least in mucous retention cysts and that tenascin produced by those cells plays an important role in differentiation of endothelial cells.

In vitro model alveoli from photodegradable microsphere templates†

PubMed Central

Lewis, Katherine J. R.; Tibbitt, Mark W.; Zhao, Yi; Branchfield, Kelsey; Sun, Xin; Balasubramaniam, Vivek; Anseth, Kristi S.

2016-01-01

Recreating the 3D cyst-like architecture of the alveolar epithelium in vitro has been challenging to achieve in a controlled fashion with primary lung epithelial cells. Here, we demonstrate model alveoli formed within a tunable synthetic biomaterial platform using photodegradable microspheres as templates to create physiologically relevant, cyst structures. Poly(ethylene glycol) (PEG)-based hydrogels were polymerized in suspension to form microspheres on the order of 120 μm in diameter. The gel chemistry was designed to allow erosion of the microspheres with cytocompatible light doses (≤15 min exposure to 10 mW cm−2 of 365 nm light) via cleavage of a photolabile nitrobenzyl ether crosslinker. Epithelial cells were incubated with intact microspheres, modified with adhesive peptide sequences to facilitate cellular attachment to and proliferation on the surface. A tumor-derived alveolar epithelial cell line, A549, completely covered the microspheres after only 24 hours, whereas primary mouse alveolar epithelial type II (ATII) cells took ~3 days. The cell-laden microsphere structures were embedded within a second hydrogel formulation at user defined densities; the microsphere templates were subsequently removed with light to render hollow epithelial cysts that were cultured for an additional 6 days. The resulting primary cysts stained positive for cell–cell junction proteins (β-catenin and ZO-1), indicating the formation of a functional epithelial layer. Typically, primary ATII cells differentiated in culture to the alveolar epithelial type I (ATI) phenotype; however, each cyst contained ~1–5 cells that stained positive for an ATII marker (surfactant protein C), which is consistent with ATII cell numbers in native mouse alveoli. This biomaterial-templated alveoli culture system should be useful for future experiments to study lung development and disease progression, and is ideally suited for co-culture experiments where pulmonary fibroblasts or endothelial cells could be presented in the hydrogel surrounding the epithelial cysts. PMID:26221842

Epithelial proliferation in small ducts of salivary cystadenoma resembling atypical ductal hyperplasia of breast.

PubMed

Fahim, Lisa; Weinreb, Ilan; Alexander, Cherupushpam; Perez Ordoñez, Bayardo

2008-09-01

Salivary gland cystadenomas are cystic neoplasms with diverse architecture and cytology. Cystadenomas may have a considerable intracystic epithelial component, but an epithelial proliferation in small ducts and cysts resembling atypical ductal hyperplasia of breast has not been documented. The patient was a 68-year-old man with a slow growing right submandibular mass. He has no recurrence 13 months after resection. The tumor was polycystic and measured 3.0 x 2.5 x 2.5 cm. The epithelium of the larger cysts was composed of flat, cuboidal, columnar, and apocrine-like cells. Many of the larger cysts showed "Roman bridges", epithelial tufting, and papillae. The smaller cysts and ducts had apocrine-like cells forming secondary glandular lumens. The ductal cells were surrounded by clear myoepithelial cells. Nuclear pleomorphism and hyperchromasia was seen in the apocrine-like cells. Adjacent to the larger cysts, there was an adenomatoid proliferation of small ducts surrounded by myoepithelial cells. No mitotic activity, necrosis, or stromal invasion was identified. The ductal cells were diffusely positive for keratin 7 and androgen receptors with focal expression of keratin 19 and high-molecular weight keratin. S-100, estrogen and progesterone receptors, and BRST-2 were negative in the ductal cells. Recognition of a prominent intraductal epithelial component in cystadenomas is important to avoid a misdiagnosis of cystadenocarcinoma or low-grade salivary duct carcinoma. Cystadenomas join the list of salivary gland lesions with microscopic similarities to primary lesions of the breast.

Desmosomes: A light microscopic and ultrastructural analysis of desmosomes in odontogenic cysts.

PubMed

Raju, Pratima; Wadhwan, Vijay; Chaudhary, Minal S

2014-01-01

Desmosomes together with adherens junctions represent the major adhesive cell-cell junctions of epithelial cells. Any damage to these junctions leads to loss of structural balance. The present study was designed to analyze the desmosomal junctions in different odontogenic cysts and compare them with their corresponding hematoxylin and eosin (H and E)   stained sections. Ten cases each of odontogenic keratocyst (OKC), dentigerous cysts (DCs), radicular cysts (RCs) and normal mucosa were stained with hematoxylin and eosin. Scanning electron microscopy (SEM) analysis of the sections was then carried out of all the sections. The area of interest on H and E stained section was marked and this marking was later superimposed onto the corresponding unstained sections and were subjected to SEM analysis. OKC at ×1000 magnification showed many prominent desmosomes. However, an increase in the intercellular space was also noted. SEM analysis demonstrated similar findings with the presence of many desmosomes, though they were seen to be damaged and fragile. H and E stained DC under oil immersion did not show any prominent desmosomes. SEM analysis of the same confirmed the observation and very minimal number were seen with a very condense arrangement of the epithelial cells. RC at ×1000 magnification revealed plenty of desmosomes, which were again confirmed by SEM. The number and quality of desmosomal junctions in all the cysts has a role in the clinical behavior of the cyst.

Uncommon formation of two antiparallel sperm bundles per cyst in tenebrionid beetles (Coleoptera)

NASA Astrophysics Data System (ADS)

Dias, Glenda; Yotoko, Karla S. C.; Gomes, Luiz F.; Lino-Neto, José

2012-09-01

Several species of Tenebrionidae are stored-grain pests. Since they belong to a specious family, the systematics of these beetles is still in doubt. In insects, spermatogenesis and the spermatozoa exhibit great diversity, and are therefore commonly used in phylogenetic and taxonomic analyses. During the spermatogenetic process in these organisms, the cells originating from a single spermatogonium develop synchronically in groups referred to as cysts. At the end of this process, there is usually only one sperm bundle per cyst, with all the cells in the same orientation. This paper details the spermiogenesis of the tenebrionid beetles Tenebrio molitor, Zophobas confusa, Tribolium castaneum and Palembus dermestoides using whole mount and histological sections of the cysts. In these species, spermatogenesis is similar to that which occurs in most insects. However, during spermiogenesis, the nuclei of the spermatids migrate to two opposite regions at the periphery of the cyst, leading to the uncommon formation of two bundles of spermatozoa per cyst. This feature is possibly an apomorphy for Tenebrionidae.

Epithelial Membrane Protein 2 and β1 integrin signaling regulate APC-mediated processes.

PubMed

Lesko, Alyssa C; Prosperi, Jenifer R

2017-01-01

Adenomatous Polyposis Coli (APC) plays a critical role in cell motility, maintenance of apical-basal polarity, and epithelial morphogenesis. We previously demonstrated that APC loss in Madin Darby Canine Kidney (MDCK) cells increases cyst size and inverts polarity independent of Wnt signaling, and upregulates the tetraspan protein, Epithelial Membrane Protein 2 (EMP2). Herein, we show that APC loss increases β1 integrin expression and migration of MDCK cells. Through 3D in vitro model systems and 2D migration analysis, we have depicted the molecular mechanism(s) by which APC influences polarity and cell motility. EMP2 knockdown in APC shRNA cells revealed that APC regulates apical-basal polarity and cyst size through EMP2. Chemical inhibition of β1 integrin and its signaling components, FAK and Src, indicated that APC controls cyst size and migration, but not polarity, through β1 integrin and its downstream targets. Combined, the current studies have identified two distinct and novel mechanisms required for APC to regulate polarity, cyst size, and cell migration independent of Wnt signaling. Copyright © 2016 Elsevier Inc. All rights reserved.

Gastrointestinal manifestations of mitochondrial disorders: a systematic review

PubMed Central

Finsterer, Josef; Frank, Marlies

2016-01-01

Mitochondrial disorders (MIDs) due to respiratory-chain defects or nonrespiratory chain defects are usually multisystem conditions [mitochondrial multiorgan disorder syndrome (MIMODS)] affecting the central nervous system (CNS), peripheral nervous system, eyes, ears, endocrine organs, heart, kidneys, bone marrow, lungs, arteries, and also the intestinal tract. Frequent gastrointestinal (GI) manifestations of MIDs include poor appetite, gastroesophageal sphincter dysfunction, constipation, dysphagia, vomiting, gastroparesis, GI pseudo-obstruction, diarrhea, or pancreatitis and hepatopathy. Rare GI manifestations of MIDs include dry mouth, paradontosis, tracheoesophageal fistula, stenosis of the duodeno-jejunal junction, atresia or imperforate anus, liver cysts, pancreas lipomatosis, pancreatic cysts, congenital stenosis or obstruction of the GI tract, recurrent bowel perforations with intra-abdominal abscesses, postprandial abdominal pain, diverticulosis, or pneumatosis coli. Diagnosing GI involvement in MIDs is not at variance from diagnosing GI disorders due to other causes. Treatment of mitochondrial GI disease includes noninvasive or invasive measures. Therapy is usually symptomatic. Only for myo-neuro-gastro-intestinal encephalopathy is a causal therapy with autologous stem-cell transplantation available. It is concluded that GI manifestations of MIDs are more widespread than so far anticipated and that they must be recognized as early as possible to initiate appropriate diagnostic work-up and avoid any mitochondrion-toxic treatment. PMID:28286566

Regression of experimentally induced endometriosis with a new selective cyclooxygenase-2 enzyme inhibitor.

PubMed

Kilico, Ismail; Kokcu, Arif; Kefeli, Mehmet; Kandemir, Bedri

2014-01-01

Cyclooxygenase-2 (COX-2) levels increase in women with endometriosis. COX-2, via increasing prostaglandin E2, contributes to an increase in vascular endothelial growth factor. In this way, COX-2 may contribute to the progression and continuity of endometriosis. We investigated the effect of dexketoprofen trometamol, a new selective COX-2 enzyme inhibitor, on experimentally induced endometriotic cysts. Experimental endometriotic cysts were created in 60 adult female Wistar albino rats. The rats were randomized to 2 equal groups, a control (group Con) and a dexketoprofen (group Dex) group. Six weeks later, cyst volumes were measured as in vivo (volume 1). Following volume 1 measurement, for 4 weeks group Con received 0.1 ml distilled water; group Dex received 0.375 mg dexketoprofen trometamol/0.1 ml distilled water, intramuscularly, twice a day. At the end of administration, the cyst volumes were remeasured (volume 2), and the cysts totally excised and weighed. Glandular (GT) and stromal tissues (ST) and natural killer (NK) cell contents in the cyst wall were scored. NK cell content and volume 1 were not different between the 2 groups. Volume 2, cyst weight, and GT and ST contents in group Dex were significantly lower than those in group Con. Dexketoprofen trometamol significantly reduced the development of experimentally induced endometriotic cysts both macroscopically and microscopically.

Primary iris stromal cyst with rapid growth.

PubMed

Xiao, Yang; Wang, Yu-Hong; Niu, Gai-Ling; Gao, Min

2009-11-01

To describe the clinical features and the surgical management of primary iris stromal cyst with rapid growth. A 14-year-old Chinese-Mongolian girl was referred to us with a 1-month history of obstructed vision and photophobia. On an examination, a semitransparent cyst with a densely pigmented posterior wall was revealed in the anterior chamber of the left eye. The information regarding the location and extent of the cyst was further analyzed by anterior segment optical coherence tomography and ultrasound biomicroscopy. It arose within the iris stroma, measuring 7.52 x 3.60 mm. Blood vessels on the surface of the lesion were revealed by iris angiography. There was no history of amniocentesis, birth trauma, antecedent ocular injury, or maternal illness during gestation. The diagnosis of primary iris stromal cyst was made. A combination of needle aspiration, piecemeal resection of cyst wall, cryotherapy, and argon laser photocoagulation with overlapped spots was used. Histopathology of the cyst wall revealed nonkeratinized, multilayered, stratified squamous epithelium with clusters of goblet cells. Complete resolution of the cyst was successfully achieved. The visual acuity improved to 20/25 from counting fingers. At 6 months of follow-up, there was no recurrence. Complete eradication and devitalization of any remaining epithelial cells are the key factors for preventing recurrence and diffuse epithelialization of the anterior chamber.

Towards an Ecological Understanding of Dinoflagellate Cyst Functions

PubMed Central

Bravo, Isabel; Figueroa, Rosa Isabel

2014-01-01

The life cycle of many dinoflagellates includes at least one nonflagellated benthic stage (cyst). In the literature, the different types of dinoflagellate cysts are mainly defined based on morphological (number and type of layers in the cell wall) and functional (long- or short-term endurance) differences. These characteristics were initially thought to clearly distinguish pellicle (thin-walled) cysts from resting (double-walled) dinoflagellate cysts. The former were considered short-term (temporal) and the latter long-term (resting) cysts. However, during the last two decades further knowledge has highlighted the great intricacy of dinoflagellate life histories, the ecological significance of cyst stages, and the need to clarify the functional and morphological complexities of the different cyst types. Here we review and, when necessary, redefine the concepts of resting and pellicle cysts, examining both their structural and their functional characteristics in the context of the life cycle strategies of several dinoflagellate species. PMID:27694774

Mucinous cystadenoma of the ovary with stromal luteinization and hilar cell hyperplasia during pregnancy.

PubMed

Pascal, R R; Grecco, L A

1988-02-01

A 32-year-old woman was delivered of a healthy, full-term infant by cesarean section, at which time a large ovarian cyst was removed. The cyst proved to be a mucinous cystadenoma with prominent luteinization of the stroma subtending the epithelium and with numerous foci of hyperplastic Leydig cells in the cyst wall and ovarian hilum. These hormonally induced changes must be recognized in order to avoid mistaking them for invasive epithelial components.

Pigmented epidermal cyst with dense collection of melanin: A rare entity – Report of a case with review of the literature

PubMed Central

Jayalakshmy, P. S.; Subitha, K.; Priya, P. V.; Johnson, Gerald

2012-01-01

Epidermal cyst is a very common benign cystic lesion of the skin. It is usual to find ulceration of the lining epithelium, rupture of the cyst wall with chronic inflammation and foreign body giant cell reaction. But, it is very rare to see an epidermal cyst with marked accumulation of melanin pigment. Only a few cases of pigmented epidermal cyst with dense collection of melanin pigment have been published in the literature. Here, we are reporting a case of ruptured epidermal cyst with keratin granuloma formation and showing dense collection of melanin pigment. PMID:23130289

T-helper cell type 17/regulatory T-cell immunoregulatory balance in human radicular cysts and periapical granulomas.

PubMed

Marçal, Juliana R B; Samuel, Renata O; Fernandes, Danielle; de Araujo, Marcelo S; Napimoga, Marcelo H; Pereira, Sanivia A L; Clemente-Napimoga, Juliana T; Alves, Polyanna M; Mattar, Rinaldo; Rodrigues, Virmondes; Rodrigues, Denise B R

2010-06-01

Cysts and granulomas are chronic periapical lesions mediated by a set of inflammatory mediators that develop to contain a periapical infection. This study analyzed the nature of the inflammatory infiltrate, presence of mast cells, and in situ expression of cytokines (interleukin [IL]-17 and transforming growth factor [TGF]-beta), chemokines (macrophage inflammatory protein [MIP]-1beta and monocyte chemotactic protein [MCP]-1), and nuclear transcription factor (FoxP3) in human periapical granulomas and cysts compared with a control group. Fifty-five lesions (25 periapical cysts, 25 periapical granulomas, and 5 controls) were analyzed. The type of inflammatory infiltrate was evaluated by hematoxylin-eosin staining, and the presence of mast cells was analyzed by toluidine blue staining. Indirect immunohistochemistry was used to evaluate the expression of cytokines, chemokines, and FoxP3. The inflammatory infiltrate mainly consisted of mononuclear cells. In cysts, mononuclear infiltrates were significantly more frequent than mixed (polymorphonuclear/mononuclear) infiltrates (P = .04). Mixed inflammatory infiltrates were significantly more frequent in patients with sinus tract (P = .0001). The number of mast cells was significantly higher in granulomas than in cystic lesions (P = .02). A significant difference in the expression of IL-17 (P = .001) and TGF-beta (P = .003) was observed between cysts and granulomas and the control group. Significantly higher IL-17 levels were also observed in cases of patients with sinus tract (P = .03). We observed that chronic periapical lesions might experience a reagudization process that is correlated with an increased leukocyte infiltration, with the predominance of neutrophils attracted by a chemokine milieu, as well as the increased presence of IL-17. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[Study of 103 cases of odontogenic cysts].

PubMed

Moctezuma-Bravo, Gustavo Sergio; Magallanes-González, Eduardo

2009-01-01

To describe characteristics of odontogenic cysts in a Mexican population. A retrospective study of 103 odontogenic cysts in 86 patients was done. The data were obtained from files of the Pathology Department of a General Hospital. We observed a frequency of the 8.13 % of odontogenic cysts (103) in 1266 pathological studies. The dentigerous cyst 56 % and odontogenic keratocyst 33 % were the most common odontogenic cysts. Sixty one percent of the cysts appeared in the second and third decades of life. In 71 cysts, 42 % appeared in the posterior region jaw, 29 % in the anterior region of the maxilla and 21 % in the posterior region of the maxilla. A 6.7 % developed a recurrence after treatment and a case of keratocyst of posterior region of the maxilla was associated with epidermoid carcinoma. The study included three women with the syndrome of carcinoma of the basal cell nevus, who presented multiple keratocysts. The dentigerous cysts and odontogenic keratocysts were the most frequent odontogenic cysts. They appeared mainly in the second and third decades of life.

Apoptosis as a possible mechanism of infertility in Echinococcus granulosus hydatid cysts.

PubMed

Paredes, R; Jiménez, V; Cabrera, G; Iragüen, D; Galanti, N

2007-04-01

Echinococcus granulosus is a parasitic cestode causing hydatidosis in intermediate hosts (human and herbivorous). Most symptoms of the disease occur by the pressure exerted on viscera by cysts that are formed upon ingestion of the parasite eggs excreted by definitive hosts (canines). Protoscoleces, the developmental form of the parasite infective to definitive hosts, are formed in the germinal nucleated layer of fertile hydatid cysts. For unknown reasons, some cysts are unable to produce protoscoleces (infertile hydatid cysts). In this study, analysis of DNA fragmentation using TUNEL and agarose gel electrophoresis showed higher levels of apoptosis in infertile cysts as compared to fertile cysts. Additionally, caspase 3 was detected both in fertile and infertile cysts; the activity of this enzyme was found to be higher in infertile cysts. We conclude that apoptosis may be involved in hydatid cyst infertility. This is the first report on the presence of programmed cell death in E. granulosus. c 2006 Wiley-Liss, Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Otani, Satoshi; Kakinuma, Sei, E-mail: skakinuma.gast@tmd.ac.jp; Department for Liver Disease Control, Tokyo Medical and Dental University, Tokyo

Fetal hepatic stem/progenitor cells, called hepatoblasts, play central roles in liver development; however, the molecular mechanisms regulating the phenotype of these cells have not been completely elucidated. Matrix metalloproteinase (MMP)-14 is a type I transmembrane proteinase regulating pericellular proteolysis of the extracellular matrix and is essential for the activation of several MMPs and cytokines. However, the physiological functions of MMP-14 in liver development are unknown. Here we describe a functional role for MMP-14 in hepatic and biliary differentiation of mouse hepatoblasts. MMP-14 was upregulated in cells around the portal vein in perinatal stage liver. Formation of bile duct-like structures inmore » MMP-14–deficient livers was significantly delayed compared with wild-type livers in vivo. In vitro biliary differentiation assays showed that formation of cholangiocytic cysts derived from MMP-14–deficient hepatoblasts was completely impaired, and that overexpression of MMP-14 in hepatoblasts promoted the formation of bile duct-like cysts. In contrast, the expression of molecules associated with metabolic functions in hepatocytes, including hepatic nuclear factor 4α and tryptophan 2,3-dioxygenase, were significantly increased in MMP-14–deficient livers. Expression of the epidermal growth factor receptor and phosphorylation of mitogen-activated protein kinases were significantly upregulated in MMP-14–deficient livers. We demonstrate that MMP-14–mediated signaling in fetal hepatic progenitor cells promotes biliary luminal formation around the portal vein and negatively controls the maturation of hepatocytes. - Highlights: • Loss of MMP-14 delayed formation of bile duct-like structures in perinatal liver. • Overexpression of MMP-14 in hepatobalsts promoted the biliary formation in vitro. • Loss of MMP-14 promoted hepatocyte maturation of hepatoblasts in vivo. • MMP-14–mediated signaling regulates terminal differentiation of hepatoblasts.« less

Mei-P26 Cooperates with Bam, Bgcn and Sxl to Promote Early Germline Development in the Drosophila Ovary

PubMed Central

Li, Yun; Zhang, Qiao; Carreira-Rosario, Arnaldo; Maines, Jean Z.; McKearin, Dennis M.; Buszczak, Michael

2013-01-01

In the Drosophila female germline, spatially and temporally specific translation of mRNAs governs both stem cell maintenance and the differentiation of their progeny. However, the mechanisms that control and coordinate different modes of translational repression within this lineage remain incompletely understood. Here we present data showing that Mei-P26 associates with Bam, Bgcn and Sxl and nanos mRNA during early cyst development, suggesting that this protein helps to repress the translation of nanos mRNA. Together with recently published studies, these data suggest that Mei-P26 mediates both GSC self-renewal and germline differentiation through distinct modes of translational repression depending on the presence of Bam. PMID:23526974

Histone deacetylase 6 inhibition reduces cysts by decreasing cAMP and Ca2+ in knock-out mouse models of polycystic kidney disease.

PubMed

Yanda, Murali K; Liu, Qiangni; Cebotaru, Valeriu; Guggino, William B; Cebotaru, Liudmila

2017-10-27

Autosomal dominant polycystic kidney disease (ADPKD) is associated with progressive enlargement of multiple renal cysts, often leading to renal failure that cannot be prevented by a current treatment. Two proteins encoded by two genes are associated with ADPKD: PC1 ( pkd1 ), primarily a signaling molecule, and PC2 ( pkd2 ), a Ca 2+ channel. Dysregulation of cAMP signaling is central to ADPKD, but the molecular mechanism is unresolved. Here, we studied the role of histone deacetylase 6 (HDAC6) in regulating cyst growth to test the possibility that inhibiting HDAC6 might help manage ADPKD. Chemical inhibition of HDAC6 reduced cyst growth in PC1-knock-out mice. In proximal tubule-derived, PC1-knock-out cells, adenylyl cyclase 6 and 3 (AC6 and -3) are both expressed. AC6 protein expression was higher in cells lacking PC1, compared with control cells containing PC1. Intracellular Ca 2+ was higher in PC1-knock-out cells than in control cells. HDAC inhibition caused a drop in intracellular Ca 2+ and increased ATP-simulated Ca 2+ release. HDAC6 inhibition reduced the release of Ca 2+ from the endoplasmic reticulum induced by thapsigargin, an inhibitor of endoplasmic reticulum Ca 2+ -ATPase. HDAC6 inhibition and treatment of cells with the intracellular Ca 2+ chelator 1,2-bis(2-aminophenoxy)ethane- N , N , N ', N '-tetraacetic acid tetrakis(acetoxymethyl ester) reduced cAMP levels in PC1-knock-out cells. Finally, the calmodulin inhibitors W-7 and W-13 reduced cAMP levels, and W-7 reduced cyst growth, suggesting that AC3 is involved in cyst growth regulated by HDAC6. We conclude that HDAC6 inhibition reduces cell growth primarily by reducing intracellular cAMP and Ca 2+ levels. Our results provide potential therapeutic targets that may be useful as treatments for ADPKD. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Ki-67 and MCM-2 in Dental Follicle and Odontogenic Cysts: The Effects of Inflammation on Proliferative Markers

PubMed Central

Güler, Nurhan; Çomunoğlu, Nil; Cabbar, Fatih

2012-01-01

The aim of this study was to investigate whether there is any association between inflammation and the expression of markers of cell cycle entry (Ki-67 and MCM-2) in dental follicle (DF) of asymptomatic impacted teeth and odontogenic cysts. The study consisted of 70 DFs and 20 odontogenic cysts (radicular cyst (RC), dentigerous cyst (DC) and keratocytic odontogenic tumor (KCOT) located at posterior mandibular region. Histological findings of inflammation for all specimen and mucous cell prosoplasia, squamous metaplasia, glandular epithelium for all DFs were stained with hematoxyline and eosin, periodic acid schiff, alcian blue, and mucin. Epithelial cell proliferation was determined by using immunohistochemical labeling for Ki-67 and MCM-2. The histologic examinations showed 16% mucous cell prosoplasia, 54% squamous metaplasia, 20% glandular epithelium, 37% inflammation. Inflammation was detected in all RCs and %62 in DF, %43 in DC and KCOT. Positive correlation was found between the inflammation of DF and odontogenic cysts (P < 0.01). The mean Ki-67 and MCM-2 expressions were found 9, 64 ± 5, 99 and 6, 34 ± 3, 81 in DF, 11, 85 ± 9, 01 and 13, 6 ± 9, 94 in odontogenic cysts, respectively. While the mean Ki-67 expressions were statistically significant in DF and KCOT (P < 0.01), MCM-2 were significant in RC and KCOT (P < 0.01). MCM-2 expresion in RCs were statistically significant than KCOT (P < 0.01). The results of this study indicated that the higher MCM-2 expressions in RC than the KCOT might be related to the inflammation and this protein might be more sensitive to inflammation. PMID:22778705

Ki-67 and MCM-2 in dental follicle and odontogenic cysts: the effects of inflammation on proliferative markers.

PubMed

Güler, Nurhan; Comunoğlu, Nil; Cabbar, Fatih

2012-01-01

The aim of this study was to investigate whether there is any association between inflammation and the expression of markers of cell cycle entry (Ki-67 and MCM-2) in dental follicle (DF) of asymptomatic impacted teeth and odontogenic cysts. The study consisted of 70 DFs and 20 odontogenic cysts (radicular cyst (RC), dentigerous cyst (DC) and keratocytic odontogenic tumor (KCOT) located at posterior mandibular region. Histological findings of inflammation for all specimen and mucous cell prosoplasia, squamous metaplasia, glandular epithelium for all DFs were stained with hematoxyline and eosin, periodic acid schiff, alcian blue, and mucin. Epithelial cell proliferation was determined by using immunohistochemical labeling for Ki-67 and MCM-2. The histologic examinations showed 16% mucous cell prosoplasia, 54% squamous metaplasia, 20% glandular epithelium, 37% inflammation. Inflammation was detected in all RCs and %62 in DF, %43 in DC and KCOT. Positive correlation was found between the inflammation of DF and odontogenic cysts (P < 0.01). The mean Ki-67 and MCM-2 expressions were found 9, 64 ± 5, 99 and 6, 34 ± 3, 81 in DF, 11, 85 ± 9, 01 and 13, 6 ± 9, 94 in odontogenic cysts, respectively. While the mean Ki-67 expressions were statistically significant in DF and KCOT (P < 0.01), MCM-2 were significant in RC and KCOT (P < 0.01). MCM-2 expresion in RCs were statistically significant than KCOT (P < 0.01). The results of this study indicated that the higher MCM-2 expressions in RC than the KCOT might be related to the inflammation and this protein might be more sensitive to inflammation.

Immunohistochemical evaluation of inducible nitric oxide synthase in the epithelial lining of odontogenic cysts: A qualitative and quantitative analysis

PubMed Central

Akshatha, B K; Karuppiah, Karpagaselvi; Manjunath, G S; Kumarswamy, Jayalakshmi; Papaiah, Lokesh; Rao, Jyothi

2017-01-01

Introduction: The three common odontogenic cysts include radicular cysts (RCs), dentigerous cysts (DCs), and odontogenic keratocysts (OKCs). Among these 3 cysts, OKC is recently been classified as benign keratocystic odontogenic tumor attributing to its aggressive behavior, recurrence rate, and malignant potential. The present study involved qualitative and quantitative analysis of inducible nitric oxide synthase (iNOS) expression in epithelial lining of RCs, DCs, and OKCs, compare iNOS expression in epithelial linings of all the 3 cysts and determined overexpression of iNOS in OKCs which might contribute to its aggressive behavior and malignant potential. Aims: The present study is to investigate the role of iNOS in the pathogenesis of OKCs, DCs, and RCs by evaluating the iNOS expression in the epithelial lining of these cysts. Subjects and Methods: Analysis of iNOS expression in epithelial lining cells of 20 RCs, 20 DCs, and 20 OKCs using immunohistochemistry done. Statistical Analysis Used: The percentage of positive cells and intensity of stain was assessed and compared among all the 3 cysts using contingency coefficient. Kappa statistics for the two observers were computed for finding interobserver agreement. Results: The percentage of iNOS-positive cells was found to be remarkably high in OKCs (12/20) –57.1% as compared to RCs (6/20) – 28.6% and DCs (3/20) – 14.3%. The interobserver agreement for iNOS-positive percentage cells was arrived with kappa values with OKCs → Statistically significant (P > 0.000), RCs → statistically significant (P > 0.001) with no significant values for DCs. No statistical difference exists among 3 study samples in regard to the intensity of staining with iNOS. Conclusions: Increased iNOS expression in OKCs may contribute to bone resorption and accumulation of wild-type p53, hence, making OKCs more aggressive. PMID:29391711

Immunohistochemical Analysis of P63 Expression in Odontogenic Lesions

PubMed Central

Atarbashi Moghadam, Saede; Atarbashi Moghadam, Fazele; Eini, Ebrahim

2013-01-01

P63 may have a role in tumorigenesis and cytodifferentiation of odontogenic lesions. We investigated the immunohistochemical expression of P63 in a total of 30 cases of odontogenic cysts and tumors. The percentage of positive cells was calculated in the lining of odontogenic cysts and islands of ameloblastoma. P63 expression was evident in all types of odontogenic lesions. P63 was expressed throughout the lining epithelium of odontogenic keratocyst except surface parakeratinized layer. In addition, calcifying odontogenic cyst showed P63 expression in all layers. In almost all radicular and dentigerous cysts, the basal and parabasal layers were immunoreactive. Peripheral cells of ameloblastoma expressed P63; however, stellate reticulum had weaker immunostaining. No significant difference in P63 expression was observed between studied lesions (P = 0.86). Expression of P63 in odontogenic lesions suggests that this protein is important in differentiation and proliferation of odontogenic epithelial cells. However, it seems that it could not be a useful marker to differentiate between aggressive and nonaggressive lesions. P63 also represents a progenitor or basal cell marker, and it is not expressed in mature differentiated cells. PMID:24350278

Glycogen synthase kinase-3β promotes cyst expansion in polycystic kidney disease.

PubMed

Tao, Shixin; Kakade, Vijayakumar R; Woodgett, James R; Pandey, Pankaj; Suderman, Erin D; Rajagopal, Madhumitha; Rao, Reena

2015-06-01

Polycystic kidney diseases (PKDs) are inherited disorders characterized by the formation of fluid filled renal cysts. Elevated cAMP levels in PKDs stimulate progressive cyst enlargement involving cell proliferation and transepithelial fluid secretion often leading to end-stage renal disease. The glycogen synthase kinase-3 (GSK3) family of protein kinases consists of GSK3α and GSK3β isoforms and has a crucial role in multiple cellular signaling pathways. We previously found that GSK3β, a regulator of cell proliferation, is also crucial for cAMP generation and vasopressin-mediated urine concentration by the kidneys. However, the role of GSK3β in the pathogenesis of PKDs is not known. Here we found that GSK3β expression and activity were markedly upregulated and associated with cyst-lining epithelia in the kidneys of mice and humans with PKD. Renal collecting duct-specific gene knockout of GSK3β or pharmacological inhibition of GSK3 effectively slowed down the progression of PKD in mouse models of autosomal recessive or autosomal dominant PKD. GSK3 inactivation inhibited cAMP generation and cell proliferation resulting in reduced cyst expansion, improved renal function, and extended life span. GSK3β inhibition also reduced pERK, c-Myc, and cyclin-D1, known mitogens in proliferation of cystic epithelial cells. Thus, GSK3β has a novel functional role in PKD pathophysiology, and its inhibition may be therapeutically useful to slow down cyst expansion and progression of PKD.

Role of matrix metalloproteinases in radicular cysts and periapical granulomas.

PubMed

D'addazio, G; Artese, L; Piccirilli, M; Perfetti, G

2014-01-01

The aim of the present study was to evaluate the expression and distribution of different classes of matrix metalloproteinases (MMPs) in radicular cysts and periapical granulomas. Twenty consecutive specimens of radicular cysts and 20 of periapical granulomas were selected. Expression of MMP-2, -9, -8, -13, -3 was immunohistochemically evaluated. The intensity of expression of the MMPs was evaluated using a semi-quantitative analysis: low = +; intermediate = ++; high = +++. Positive expression of MMPs was present with different distribution. MMP-9 expressed differently in the lesions. Indeed, in periapical granulomas low expression was found in endothelial cells and fibroblasts, whilst high intensities were only detected in inflammatory cells. On the contrary, in radicular cysts the high intensities were mainly present in keratinocytes and fibroblasts. MMP-8 was mainly expressed in inflammatory cells of periapical granulomas. MMP-2 and -3 presented a low intensity of expression in both groups. MMP-13 showed a variable pattern of distribution in the different cell types of the two different lesions. The present investigation supports the role of MMPs in the inflammatory process leading to the development of radicular cysts and periapical granulomas. The results of the present study suggested that the increased enlargement of radicular cysts, compared to periapical granulomas, might be related to a higher expression of MMP-9. On the other hands, the higher intensity of expression of MMP-8 in periapical granulomas could be related to an active inflammatory process. MMP-8 could play an important role in the inflammation processes during the development of periapical lesions.

The dysraphic state of the posterior fossa. Clinical review of the Dandy-Walker syndrome and the so-called arachnoid cysts.

PubMed

Carteri, A; Gerosa, M; Gaini, S M; Villani, R

1979-01-01

The Authors report their case material concerning some basic items of the dysraphic pathology of the Posterior Fossa: 22 cases of Dandy Walker syndromes (DWS) and "Arachnoid Cysts" (PFC). The mean clinical findings (predominant involvement of the vestibular structures of the brain stem in the DWS, frequent epileptic seizures and some cases of hypothalamic disturbances in the PFC) are discussed in the light of current embryological theories on Weed's "area membranacea". Finally the results of differential surgical treatments are examined: good or satisfactory results were obtained with shunts, while still debatable seems to be the direct surgical approach.

Mapping the CgrA regulon of Rhodospirillum centenum reveals a hierarchal network controlling Gram-negative cyst development.

PubMed

Dong, Qian; Fang, Mingxu; Roychowdhury, Sugata; Bauer, Carl E

2015-12-16

Several Gram-negative species undergo development leading to the formation of metabolically dormant desiccation resistant cysts. Recent analysis of cyst development has revealed that ~20 % of the Rhodospirillum centenum transcriptome undergo temporal changes in expression as cells transition from vegetative to cyst forms. It has also been established that one trigger for cyst formation is the synthesis of the signaling nucleotide 3', 5'- cyclic guanosine monophosphate (cGMP) that is sensed by a homolog of the catabolite repressor protein called CgrA. CgrA in the presence of cGMP initiate a cascade of gene expression leading to the development of cysts. In this study, we have used RNA-seq and chromatin immunoprecipitation (ChIP-Seq) techniques to define the CgrA-cGMP regulon. Our results indicate that disruption of CgrA leads to altered expression of 258 genes, 131 of which have been previously reported to be involved in cyst development. ChIP-seq analysis combined with transcriptome data also demonstrates that CgrA directly regulates the expression of numerous sigma factors and transcription factors several of which are known to be involved in cyst cell development. This analysis reveals the presence of CgrA binding sites upstream of many developmentally regulated genes including many transcription factors and signal transduction components. CgrA thus functions as master controller of the cyst development by initiating a hierarchal cascade of downstream transcription factors that induces temporal expression of encystment genes.

The new reports on life cycle of Heterosigma akashiwo (Raphidophyceae)

NASA Astrophysics Data System (ADS)

Kim, J. H.

2016-02-01

Heterosigma akashiwo (Hada) Hada (Raphidophyceae) is a noxious bloom-forming algal species that has damaged many fish farms in coastal waters during recent decades. Consequently, many studies focused on the population dynamics of H. akashiwo, while its life cycle was not well studied. In this study, we investigated veiled life cycle of H. akashiwo through culture based method. We cultured eight H. akashiwostrains originated from Korea, Japan, USA under various conditions (water temp., light intensity, salinity, pH). Morphological diversity of cells were observed via light microscopy and scanning electron microscopy. To observe nucleus of living cell, cells were stained with Hoechst and changes of cells in culture were observed through time-lapse. For observation of cysts and their germination process, cysts were isolated from sediment. Different from the previous knowledge, H. akashiwo has only vegetative cell stage and cyst stage, we discovered that H. akashiwo has extra small cell stage and large cell stage. Large cells are much bigger (20-45 µm) than vegetative cells. Large cell formation was resulted from fusion of vegetative cells. Small cells were very small (6.88 ± 0.85 µm), these cell divided from large cell or formed in germination process of cysts rarely. Small cells have lower motility than vegetative cells. These results improved the study of life stages of H. akashiwo and this fundamental investigation provide important new information and improve our understanding of the life cycle of H. akashiwo.

Why was the 2012 bloom so early? Using chilling and warming metrics to resolve interannual variability in the timing of Alexandrium fundyense bloom initiation

NASA Astrophysics Data System (ADS)

Fischer, A. D.; Anderson, D. M.; Moore, S.; Brosnahan, M.

2016-02-01

The Nauset Marsh System (NMS) on Cape Cod (MA, USA) has recurrent Alexandrium fundyense blooms that have caused nearly annual shellfishing closures due to paralytic shellfish poisoning. Blooms were observed over a multi-year period (2009-2015) to examine the effects of seasonal cooling and warming on the transition from resting cysts to vegetative cells in the plankton. The life cycle processes of cyst dormancy, germination, and vegetative cell growth are all uniquely sensitive to temperature, which can translate to changes in bloom initiation phenology. Bloom initiation (>100 cells/l-1) occurred as early as 14 February 2012, and as late as 15 April 2015. To quantitatively examine the mechanisms responsible for this two-month range, laboratory studies were performed. In experiments mimicking winter's onset, mature cysts were exposed to chilling temperatures (2-8°C), and at regular intervals the germination potential of cyst cohorts was evaluated. Next, in experiments mimicking a range of late-winter, early-spring temperatures, the time to germination was observed for cold-conditioned cysts. To account for the interannual temperature variability in the NMS and enable comparison to laboratory studies, we calculated growing degree-days and chilling-units, both metrics that tabulate accumulated temperature exposures. Here we pair laboratory studies with seven years of bloom data to present a conceptual model of three temperature-dependent phases of bloom initiation for A. fundyense: 1) Winter dormancy. As temperatures cool, cysts enter a state of dormancy during which germination is physiologically inhibited, until they experience a threshold of winter chilling. 2) Quiescence. Cysts are physiologically able to germinate, but require a specific amount of heat, oxygen, and light. 3) Growth. Germling cells transform to vegetative cells, which divide asexually as a function of heat to create the bloom. These results help to explain differences in bloom timing between years, and provide insights into potential responses of A. fundyense to climate change.

A new concept of the pathogenesis of oral mucous cysts based on a study of 200 cases.

PubMed

Praetorius, F; Hammarstrom, L

1992-05-01

A new hypothesis regarding the pathogenesis of mucous cysts of the oral mucosa is proposed. Based upon a histological study of 188 mucous cysts without epithelial lining out of a total of 200 cysts it is claimed that some cysts may not develop in any of the hitherto described ways as intraductal "mucous retention cysts" or extraductal "mucous extravasation cysts" or from destruction of acini due to the pressure of mucous caused by duct obstruction. It is suggested that some of the cysts, that are found to have developed intraglandularly, are caused by traumatic destruction of a large amount of glandular acini ("parenchymal destruction cysts") and continuous secretion from the remaining acini. The mucus from the disintegrated cells forms a pool, which in time is surrounded by a connective tissue capsule that contains remnants of parenchyma from the affected lobule. This parenchyma degenerates, and eventually the cyst shows the same histological picture as the "mucous extravasation cyst". It is argued that the presence of a feeder duct does not necessarily indicate an extravasation cyst, but may be seen in the "parenchymal destruction cysts" as well. Of the 188 cysts examined 20 (11 per cent) were found to develop intraglandularly, and 36 (19 per cent) were considered probably to have developed intraglandularly.

Branched-chain amino acids enhance cyst development in autosomal dominant polycystic kidney disease.

PubMed

Yamamoto, Junya; Nishio, Saori; Hattanda, Fumihiko; Nakazawa, Daigo; Kimura, Toru; Sata, Michio; Makita, Minoru; Ishikawa, Yasunobu; Atsumi, Tatsuya

2017-08-01

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the progressive development of kidney and liver cysts. The mammalian target of rapamycin (mTOR) cascade is one of the important pathways regulating cyst growth in ADPKD. Branched-chain amino acids (BCAAs), including leucine, play a crucial role to activate mTOR pathway. Therefore, we administered BCAA dissolved in the drinking water to Pkd1 flox/flox :Mx1-Cre (cystic) mice from four to 22 weeks of age after polyinosinic-polycytidylic acid-induced conditional Pkd1 knockout at two weeks of age. The BCAA group showed significantly greater kidney/body weight ratio and higher cystic index in both the kidney and liver compared to the placebo-treated mice. We found that the L-type amino acid transporter 1 that facilitates BCAA entry into cells is strongly expressed in cells lining the cysts. We also found increased cyst-lining cell proliferation and upregulation of mTOR and mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathways in the BCAA group. In vitro, we cultured renal epithelial cell lines from Pkd1 null mice with or without leucine. Leucine was found to stimulate cell proliferation, as well as activate mTOR and MAPK/ERK pathways in these cells. Thus, BCAA accelerated disease progression by mTOR and MAPK/ERK pathways. Hence, BCAA may be harmful to patients with ADPKD. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Development of the Statocyst in Aplysia Californica. Part 1; Observations on Statoconial Development

NASA Technical Reports Server (NTRS)

Wiederhold, Michael L.; Sharma, Jyotsna S.; Driscoll, Brian P.; Harrison, Jeffrey L.

1990-01-01

The gravity receptor organs of gastropod molluscs, such as Aplysia californica, are bilateral paired statocysts, which contain dense statoconia within a fluid-filled cyst. Gravitational forces on the statoconia are sensed through their interaction with ciliated mechanoreceptor cells in the wall of the cyst. Larval Aplysia contain a single statolith within each statocyst; when the animals grow to a critical size, they begin producing multiple statoconia, a process that continues throughout life. The number of statoconia is highly correlated with animal weight but poorly correlated with age, indicating that stone production is related to total metabolism. The single statolith has an amorphous internal structure whereas the multiple statoconia have calcification deposited on concentric layers of membrane or matrix protein. The statolith appears to be produced within the cyst lumen but the multiple statoconia are produced within supporting cells between the receptor cells. Large adult animals have statoconia larger than those in early post-metamorphic animals which have just started producing multiple stones. The maximum statocyst diameter at which the receptor-cell cilia can suspend the statolith in the center of the cyst lumen is 45 micrometers; production of multiple stones begins when the cyst reaches this size. The mechanisms by which statoconia production is initiated and controlled are discussed.

Acinar cell cystadenoma of the pancreas: a benign neoplasm or non-neoplastic ballooning of acinar and ductal epithelium?

PubMed

Singhi, Aatur D; Norwood, Stephanie; Liu, Ta-Chiang; Sharma, Rajni; Wolfgang, Christopher L; Schulick, Richard D; Zeh, Herbert J; Hruban, Ralph H

2013-09-01

Acinar cell cystadenoma (ACA) of the pancreas was initially described as a non-neoplastic cyst of the pancreas and, at that time, referred to as "acinar cystic transformation." In subsequent studies, these lesions were given the designation of "-oma," despite the relative lack of evidence supporting a neoplastic process. To characterize these lesions further, we examined the clinical, pathologic, and immunohistochemical features of 8 ACAs. The majority of patients were female (7 of 8, 88%) and ranged in age from 18 to 57 years (mean, 43 y). Grossly, the cysts involved the head (n=5), body (n=1), or the entire pancreas (n=2). ACAs were either multilocular (n=4) or unilocular (n=4) and ranged in size from 1.8 to 15 cm (mean, 6.8 cm). Histologically, multilocular ACAs were lined by patches of acinar and ductal epithelium. Immunolabeling, including double-labeling for cytokeratin 19 and chymotrypsin, highlighted the patchy pattern of the ductal and acinar cells lining the cysts. In some areas, the cysts with patches of acinar and ductal differentiation formed larger locules with incomplete septa as they appeared to fuse with other cysts. In contrast, the unilocular cases were lined by 1 to 2 cell layers of acinar cells with little intervening ductal epithelium. Nuclear atypia, mitotic figures, necrosis, infiltrative growth, and associated invasive carcinoma were absent in all cases. In addition, we assessed the clonal versus polyclonal nature of ACAs, occurring in women, using X-chromosome inactivation analysis of the human androgen receptor (AR) gene. Five of 7 cases were informative and demonstrated a random X-chromosome inactivation pattern. Clinical follow-up information was available for all patients, and follow-up ranged from 10 months to 7.8 years (mean, 3.6 y), with no evidence of recurrence or malignant transformation. We hypothesize that early lesions are marked by acinar dilatation that expands into and incorporates smaller ductules and later larger ducts. As the cysts increase in size, they fuse forming larger cysts. Later lesions demonstrate a unilocular cyst lined by predominantly acinar epithelium with scattered ductal cells. The term cystadenoma, with its neoplastic connotation, does not seem to accurately reflect the histologic, immunohistochemical, or molecular features of these lesions. We suggest readopting the term "acinar cystic transformation" until the non-neoplastic versus neoplastic origin of these lesions can be resolved.

Developmental Patterning: Putting the Squeeze on Mis-specified Cells.

PubMed

Nakajima, Yu-Ichiro; Gibson, Matthew C

2016-03-07

Widely implicated in human disease, abnormal cellular cysts reflect dramatic defects in the maintenance of epithelial integrity. A new study reports that epithelial cysts may arise as a surprisingly general consequence of clonal defects in the specification of cell identity. Copyright © 2016 Elsevier Ltd. All rights reserved.

The novel cyst nematode effector protein 19C07 interacts with the Arabidopsis auxin influx transporter LAX3 to control feeding site development.

PubMed

Lee, Chris; Chronis, Demosthenis; Kenning, Charlotte; Peret, Benjamin; Hewezi, Tarek; Davis, Eric L; Baum, Thomas J; Hussey, Richard; Bennett, Malcolm; Mitchum, Melissa G

2011-02-01

Plant-parasitic cyst nematodes penetrate plant roots and transform cells near the vasculature into specialized feeding sites called syncytia. Syncytia form by incorporating neighboring cells into a single fused cell by cell wall dissolution. This process is initiated via injection of esophageal gland cell effector proteins from the nematode stylet into the host cell. Once inside the cell, these proteins may interact with host proteins that regulate the phytohormone auxin, as cellular concentrations of auxin increase in developing syncytia. Soybean cyst nematode (Heterodera glycines) Hg19C07 is a novel effector protein expressed specifically in the dorsal gland cell during nematode parasitism. Here, we describe its ortholog in the beet cyst nematode (Heterodera schachtii), Hs19C07. We demonstrate that Hs19C07 interacts with the Arabidopsis (Arabidopsis thaliana) auxin influx transporter LAX3. LAX3 is expressed in cells overlying lateral root primordia, providing auxin signaling that triggers the expression of cell wall-modifying enzymes, allowing lateral roots to emerge. We found that LAX3 and polygalacturonase, a LAX3-induced cell wall-modifying enzyme, are expressed in the developing syncytium and in cells to be incorporated into the syncytium. We observed no decrease in H. schachtii infectivity in aux1 and lax3 single mutants. However, a decrease was observed in both the aux1lax3 double mutant and the aux1lax1lax2lax3 quadruple mutant. In addition, ectopic expression of 19C07 was found to speed up lateral root emergence. We propose that Hs19C07 most likely increases LAX3-mediated auxin influx and may provide a mechanism for cyst nematodes to modulate auxin flow into root cells, stimulating cell wall hydrolysis for syncytium development.

[Effect of Echinococcus multilocularis Cyst Fluid on the Expression of Five MAPK-pathway Genes of Rat Hepatic Stellate Cells].

PubMed

Ren, Bin; Fan, Hai-ning; Deng, Yong; Wang, Hai-jiu; Ren, Li

2015-04-01

To investigate the effect of Echinococcus multilocularis cyst fluid on five MAPK (mitogen-activated protein kinase)-pathway genes of rat hepatic stellate cell. Rat hepatic stellate cell line, HSC-T6 cells were co-cultured with different protein concentrations of E. multilocularis cyst fluid (0.01, 0.025, 0.05, 0.1, 0.2, 0.4, 0.9, 1.7, 3.4, 6.8, and 13.5 mg/ml) for 24 h. HSC-T6 cells cultured with complete medium served as control group. The morphological change of cells was observed under the microscope. The expression of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and mitogen-activated protein kinase(p38) in HSC-T6 cells was detected by real time fluorescent quantitative PCR. After co-cultured for 24 h, most HSC-T6 cells in 13.5 mg/ml group shrank as a precursor to slough off; In 6.8 mg/ml group, some HSC-T6 cells shrank and changed to long fusiform shape with many slender pseudopodia; In 3.4 mg/ml group, most HSC-T6 cells showed as adherent cells with an irregular polygon shape, formed a sheet with short pseudopodia. There was no difference in cell morphology between < 1.7 mg/ml groups and control group. When the protein concentration was above 1.7 mg/ml, the mRNA level of ERK1/2, JNK1/2, and P38 increased significantly increased. In 6.8 mg/ml cyst fluid group, the mRNA level of ERK1/2, JNK1/2, and P38 was higher than that of the control (P < 0.05). 6.8 mg/ml Echinococcus multilocularis cyst fluid can have a significant impact on mRNA levels of ERK1/2, JNK1/2 and p38 in rat hepatic stellate cells.

cAMP-dependent chloride secretion mediates tubule enlargement and cyst formation by cultured mammalian collecting duct cells.

PubMed

Montesano, Roberto; Ghzili, Hafida; Carrozzino, Fabio; Rossier, Bernard C; Féraille, Eric

2009-02-01

Polycystic kidney diseases result from disruption of the genetically defined program that controls the size and geometry of renal tubules. Cysts which frequently arise from the collecting duct (CD) result from cell proliferation and fluid secretion. From mCCD(cl1) cells, a differentiated mouse CD cell line, we isolated a clonal subpopulation (mCCD-N21) that retains morphogenetic capacity. When grown in three-dimensional gels, mCCD-N21 cells formed highly organized tubular structures consisting of a palisade of polarized epithelial cells surrounding a cylindrical lumen. Subsequent addition of cAMP-elevating agents (forskolin or cholera toxin) or of membrane-permeable cAMP analogs (CPT-cAMP) resulted in rapid and progressive dilatation of existing tubules, leading to the formation of cystlike structures. When grown on filters, mCCD-N21 cells exhibited a high transepithelial resistance as well as aldosterone- and/or vasopressin-induced amiloride-sensitive and -insensitive current. The latter was in part inhibited by Na(+)-K(+)-2Cl(-) cotransporter (bumetanide) and chloride channel (NPPB) inhibitors. Real-time PCR analysis confirmed the expression of NKCC1, the ubiquitous Na(+)-K(+)-2Cl(-) cotransporter and cystic fibrosis transmembrane regulator (CFTR) in mCCD-N21 cells. Tubule enlargement and cyst formation were prevented by inhibitors of Na(+)-K(+)-2Cl(-) cotransporters (bumetanide or ethacrynic acid) or CFTR (NPPB or CFTR inhibitor-172). These results further support the notion that cAMP signaling plays a key role in renal cyst formation, at least in part by promoting chloride-driven fluid secretion. This new in vitro model of tubule-to-cyst conversion affords a unique opportunity for investigating the molecular mechanisms that govern the architecture of epithelial tubes, as well as for dissecting the pathophysiological processes underlying cystic kidney diseases.

Stage and season effects on cell cycle and apoptotic activities of germ cells and Sertoli cells during spermatogenesis in the spiny dogfish (Squalus acanthias).

PubMed

McClusky, L M

2005-01-01

To understand the processes involved in the spatial and temporal maturation of testicular cells in Squalus acanthias, we used standard morphometry, proliferating-cell nuclear antigen (PCNA) and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) immunohistochemistry. Except for immature spermatocysts (germinal zone, GZ; early-stage pre-meiotic, E-PrM), the number of cysts in all subsequent stages and the total number of cysts in the spermatogenic progression varied seasonally. The spermatogenic cycle spans about 2 years and is interrupted by germcell clone deletion via apoptosis at the mitosis-meiosis transition in April/May, manifesting as a zone of degeneration (ZD). Rate of displacement of the ZD across the testis diameter indicates that late-stage premeiotic (L-PrM) generations 12-13 require 9-10 months to reach the mature-spermatid stage. Also, the number of cysts completing spermatogenesis is approximately 4-5-fold less than the number that entered spermatogenesis proper 2 years earlier. Pronounced gonocytogenesis in the germinal ridge was coincident with ZD formation in April/May, but it was absent in the fall when mature spermatogonial and meiotic activities had resumed. Whereas strong Sertoli cell PCNA immunoreactivity dominated the GZ cyst cell-cycle activities throughout the year, except during the spring/summer months, the spermatogonial- and Sertoli-cell PCNA indices in E-PrM cysts were inversely related. PCNA immunoreactivity in spermatocytes was seasonal and dependent on the stage of meiosis. TUNEL labelling was limited to spermatogonia and increased stage-dependently in the PrM region (L-PrM = mid-stage PrM >E-PrM >GZ), correlating with ZD formation, in a season-dependent manner. Results imply that effects of normal regulatory factors in Squalus are stage- and process-specific.

Innexin2 gap junctions in somatic support cells are required for cyst formation and for egg chamber formation in Drosophila.

PubMed

Mukai, Masanori; Kato, Hirotaka; Hira, Seiji; Nakamura, Katsuhiro; Kita, Hiroaki; Kobayashi, Satoru

2011-01-01

Germ cells require intimate associations with surrounding somatic cells during gametogenesis. During oogenesis, gap junctions mediate communication between germ cells and somatic support cells. However, the molecular mechanisms by which gap junctions regulate the developmental processes during oogenesis are poorly understood. We have identified a female sterile allele of innexin2 (inx2), which encodes a gap junction protein in Drosophila. In females bearing this inx2 allele, cyst formation and egg chamber formation are impaired. In wild-type germaria, Inx2 is strongly expressed in escort cells and follicle cells, both of which make close contact with germline cells. We show that inx2 function in germarial somatic cells is required for the survival of early germ cells and promotes cyst formation, probably downstream of EGFR pathway, and that inx2 function in follicle cells promotes egg chamber formation through the regulation of DE-cadherin and Bazooka (Baz) at the boundary between germ cells and follicle cells. Furthermore, genetic experiments demonstrate that inx2 interacts with the zero population growth (zpg) gene, which encodes a germline-specific gap junction protein. These results indicate a multifunctional role for Inx2 gap junctions in somatic support cells in the regulation of early germ cell survival, cyst formation and egg chamber formation. Inx2 gap junctions may mediate the transfer of nutrients and signal molecules between germ cells and somatic support cells, as well as play a role in the regulation of cell adhesion. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Experimental evidence supports the abscess theory of development of radicular cysts.

PubMed

Nair, P N R; Sundqvist, Göran; Sjögren, Ulf

2008-08-01

The objective of this study was to experimentally induce inflammatory cysts in an animal model so as to test the hypothesis that radicular cysts develop via the "abscess pathway." Twenty-eight perforated custom-made Teflon cages were surgically implanted into defined locations in the back of 7 Sprague Dawley rats. A week after the implantation of the cages, a known quantity of freshly grown, close allogeneic oral keratinocytes in phosphate buffer solution (PBS) was injected into each cage. One cage per animal was treated as the control that received only epithelial cells. The remaining 3 cages of each animal were trials. Seven days post epithelial cell inoculation; a suspension of 0.2 mL of Fusobacterium nucleatum (10(8) bacteria per mL) was injected into each of the 3 trial cages. Two, 12, and 24 weeks after the inoculation of the bacteria, the cages were taken out, and the tissue contents were fixed and processed by correlative light and transmission electron microscopy. Sixteen of the 21 trial cages could be processed and yielded results. Inoculations of epithelial cells followed 1 week later by F. nucleatum into tissue cages resulted in the development inflammatory cysts in 2 of the 16 cages. The 2 cages contained a total of 4 cystic sites. None of the control cages showed the presence of any cyst-like pathology. Inflammatory cysts were induced by initiating acute inflammatory foci (abscess/necrotic area) by bacterial injection that got enclosed by a proliferating epithelium. This finding provides strong experimental evidence in support of the "abscess theory" of development of radicular cysts.

Scattered Deletion of PKD1 in Kidneys Causes a Cystic Snowball Effect and Recapitulates Polycystic Kidney Disease

PubMed Central

Leonhard, Wouter N.; Zandbergen, Malu; Veraar, Kimberley; van den Berg, Susan; van der Weerd, Louise; Breuning, Martijn; de Heer, Emile

2015-01-01

In total, 1 in 1000 individuals carries a germline mutation in the PKD1 or PKD2 gene, which leads to autosomal dominant polycystic kidney disease (ADPKD). Cysts can form early in life and progressively increase in number and size during adulthood. Extensive research has led to the presumption that somatic inactivation of the remaining allele initiates the formation of cysts, and the progression is further accelerated by renal injury. However, this hypothesis is primarily on the basis of animal studies, in which the gene is inactivated simultaneously in large percentages of kidney cells. To mimic human ADPKD in mice more precisely, we reduced the percentage of Pkd1-deficient kidney cells to 8%. Notably, no pathologic changes occurred for 6 months after Pkd1 deletion, and additional renal injury increased the likelihood of cyst formation but never triggered rapid PKD. In mildly affected mice, cysts were not randomly distributed throughout the kidney but formed in clusters, which could be explained by increased PKD-related signaling in not only cystic epithelial cells but also, healthy-appearing tubules near cysts. In the majority of mice, these changes preceded a rapid and massive onset of severe PKD that was remarkably similar to human ADPKD. Our data suggest that initial cysts are the principal trigger for a snowball effect driving the formation of new cysts, leading to the progression of severe PKD. In addition, this approach is a suitable model for mimicking human ADPKD and can be used for preclinical testing. PMID:25361818

Immunohistochemical expression of protein 53, murine double minute 2, B-cell lymphoma 2, and proliferating cell nuclear antigen in odontogenic cysts and keratocystic odontogenic tumor.

PubMed

Galvão, Hebel Cavalcanti; Gordón-Núñez, Manuel Antonio; de Amorim, Rivadavio Fernandes Batista; Freitas, Roseana de Almeida; de Souza, Lelia Batista

2013-01-01

Even though odontogenic cysts share a similar histogenesis, they show different growth and differentiation profile due to differences in the proliferative cellular activity. We perform an immunohistochemical assessment of protein 53 (p53), proliferating cell nuclear antigen (PCNA), B-cell lymphoma 2 (bcl-2), and murine double minute 2 (MDM2) expression in odontogenic cysts and keratocystic odontogenic tumor analyzing their correlation with the biological behavior of these lesions. By the streptavidin-biotin-peroxidase method with antibodies against p53, PCNA, bcl-2, and MDM2 proteins, 11 radicular cysts, 11 dentigerous cysts, and 11 keratocystic odontogenic tumor were analyzed. The non-parametric Mann-Whitney U-test and Kruskall-Wallis test (P ≤ 0.05) were used to analyze the data. Immunopositivity for PCNA was observed in all cases appraised, predominantly in the suprabasal layer of keratocystic odontogenic tumor epithelial lining (SD ± 19.44), but no significant differences were found among the groups of lesions. Bcl-2 immunoexpression was observed especially in the basal layer of keratocystic odontogenic tumor. PCNA LI was significantly higher than bcl-2 LI in keratocystic odontogenic tumor. MDM2 and p53 immunoexpression were not detected in the lesions studied. Among the evaluated lesions, the keratocystic odontogenic tumor showed different immunoexpression of the proliferation and apoptosis markers. The results of this study suggest that the keratocystic odontogenic tumor presents distinct biological behavior of the odontogenic cysts, as for the processes of proliferation, apoptosis, and differentiation, reinforcing the information in favor of the neoplastic nature of this lesion.

Immunohistochemical analysis of P53 protein in odontogenic cysts

PubMed Central

Gaballah, Essam Taher M.A.; Tawfik, Mohamed A.

2010-01-01

The p53 is a well-known tumor suppressor gene, the mutations of which are closely related to the decreased differentiation of cells. Findings of studies on immunohistochemical P53 expression in odontogenic cysts are controversial. The present study was carried-out to investigate the immunohistochemical expression of P53 protein in odontogenic cysts. Thirty paraffin blocks of diagnosed odontogenic cysts were processed to determine the immunohistochemical expression of P53 protein. Nine of the 11 odontogenic keratocysts (81.8%) expressed P53, one of three dentigerous cyst cases expressed P53, while none of the 16 radicular cysts expressed P53 protein. The findings of the present work supported the reclassification of OKC as keratocystic odontogenic tumor. PMID:23960493

Macrophage polarization differs between apical granulomas, radicular cysts, and dentigerous cysts.

PubMed

Weber, Manuel; Schlittenbauer, Tilo; Moebius, Patrick; Büttner-Herold, Maike; Ries, Jutta; Preidl, Raimund; Geppert, Carol-Immanuel; Neukam, Friedrich W; Wehrhan, Falk

2018-01-01

Apical periodontitis can appear clinically as apical granulomas or radicular cysts. There is evidence that immunologic factors are involved in the pathogenesis of both pathologies. In contrast to radicular cysts, the dentigerous cysts have a developmental origin. Macrophage polarization (M1 vs M2) is a main regulator of tissue homeostasis and differentiation. There are no studies comparing macrophage polarization in apical granulomas, radicular cysts, and dentigerous cysts. Forty-one apical granulomas, 23 radicular cysts, and 23 dentigerous cysts were analyzed in this study. A tissue microarray (TMA) of the 87 consecutive specimens was created, and CD68-, CD11c-, CD163-, and MRC1-positive macrophages were detected by immunohistochemical methods. TMAs were digitized, and the expression of macrophage markers was quantitatively assessed. Radicular cysts are characterized by M1 polarization of macrophages while apical granulomas show a significantly higher degree of M2 polarization. Dentigerous cysts have a significantly lower M1 polarization than both analyzed periapical lesions (apical granulomas and radicular cysts) and accordingly, a significantly higher M2 polarization than radicular cysts. Macrophage cell density in dentigerous cysts is significantly lower than in the periapical lesions. The development of apical periodontitis towards apical granulomas or radicular cysts might be directed by macrophage polarization. Radicular cyst formation is associated with an increased M1 polarization of infiltrating macrophages. In contrast to radicular cysts, dentigerous cysts are characterized by a low macrophage infiltration and a high degree of M2 polarization, possibly reflecting their developmental rather than inflammatory origin. As M1 polarization of macrophages is triggered by bacterial antigens, these results underline the need for sufficient bacterial clearance during endodontic treatment to prevent a possible M1 macrophage-derived stimulus for radicular cyst formation.

Dermoscopy-pathology relationship in seborrheic keratosis.

PubMed

Minagawa, Akane

2017-05-01

Making a definitive diagnosis of seborrheic keratosis (SK) can be challenging for the naked eye due to its wide variation in clinical features. Fortunately, however, most cases of SK exhibit the typical dermoscopic findings of fissures and ridges, hairpin vessels with white halo, comedo-like openings, and milia-like cysts, all of which are helpful to distinguish SK from melanoma, melanocytic nevus, squamous cell carcinoma, basal cell carcinoma (BCC) and other skin tumors. Histopathologically, these dermoscopic characteristics correspond to papillomatous surface of the epidermis, enlarged capillaries of the dermal papillae, pseudohorn cysts in the epidermis opened to the surface of the lesion and intraepidermal cysts, respectively. Clinicians should bear in mind that the clonal type of SK dermoscopically mimics melanoma and BCC by the presence of globule-like structures, while regressing SK exhibits a granular pattern that is similar to the peppering found in melanoma. Furthermore, milia-like cysts alone are insufficient for a conclusive diagnosis of SK because melanoma in rare cases displays cysts along with other SK-like dermoscopic findings. © 2017 Japanese Dermatological Association.

Detection and quantification of mast cell, vascular endothelial growth factor, and microvessel density in human inflammatory periapical cysts and granulomas.

PubMed

Fonseca-Silva, T; Santos, C C O; Alves, L R; Dias, L C; Brito, M; De Paula, A M B; Guimarães, A L S

2012-09-01

To identify and quantify mast cell (MC), vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in human periapical cysts and granulomas. Archived samples of cysts (n = 40) and granulomas (n = 28) were sectioned and stained with toluidine blue. MCs were identified and counted. Immunohistochemical reactions were employed to evaluate the tissue expression of VEGF and vessels. MVD was estimated by determining the areas of tissue labelled with CD31 antibody. The data were analysed using the Mann-Whitney test (P < 0.05). MCs were observed in the peripheral regions of both lesion types, whilst VEGF and MVD were distributed in the stroma. The presence of MCs was higher in cysts than in granulomas (P < 0.05). VEGF and MVD expression were similar in these lesions. The highest number of MCs was observed in cysts. Moreover, the identification of VEGF and MVD was consistent with the immune mechanisms involved in the lesions. © 2012 International Endodontic Journal.

Cytologic separation of branchial cleft cyst from metastatic cystic squamous cell carcinoma: A multivariate analysis of nineteen cytomorphologic features.

PubMed

Layfield, Lester J; Esebua, Magda; Schmidt, Robert L

2016-07-01

The separation of branchial cleft cysts from metastatic cystic squamous cell carcinomas in adults can be clinically and cytologically challenging. Diagnostic accuracy for separation is reported to be as low as 75% prompting some authors to recommend frozen section evaluation of suspected branchial cleft cysts before resection. We evaluated 19 cytologic features to determine which were useful in this distinction. Thirty-three cases (21 squamous carcinoma and 12 branchial cysts) of histologically confirmed cystic lesions of the lateral neck were graded for the presence or absence of 19 cytologic features by two cytopathologists. The cytologic features were analyzed for agreement between observers and underwent multivariate analysis for correlation with the diagnosis of carcinoma. Interobserver agreement was greatest for increased nuclear/cytoplasmic (N/C) ratio, pyknotic nuclei, and irregular nuclear membranes. Recursive partitioning analysis showed increased N/C ratio, small clusters of cells, and irregular nuclear membranes were the best discriminators. The distinction of branchial cleft cysts from cystic squamous cell carcinoma is cytologically difficult. Both digital image analysis and p16 testing have been suggested as aids in this separation, but analysis of cytologic features remains the main method for diagnosis. In an analysis of 19 cytologic features, we found that high nuclear cytoplasmic ratio, irregular nuclear membranes, and small cell clusters were most helpful in their distinction. Diagn. Cytopathol. 2016;44:561-567. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Temporal Dermoid Cyst with Unusual Imaging Appearance: Case Report.

PubMed

Abderrahmen, Khansa; Bouhoula, Asma; Aouidj, Lasaad; Jemel, Hafedh

2016-01-01

Intracranial dermoid cysts are benign, slow growing tumors derived from ectopic inclusions of epithelial cells during closure of neural tube. These lesions, accounting for less than 1% of intracranial tumors, have characteristic computed tomography (CT) and magnetic resonance imaging (MRI) appearances that generally permits preoperative diagnosis. However, the radiologic features are uncommon and the cyst can be easily misdiagnosed with other tumors in rare cases. Herein, we report a case of a left temporoparietal dermoid cyst in a 48-year-old woman that was peroperatively and histopathologically proven but not advocated on CT and MRI. Clinical, radiological and histopathological features of a dermoid cyst are reviewed.

Spatiotemporal deep imaging of syncytium induced by the soybean cyst nematode Heterodera glycines.

PubMed

Ohtsu, Mina; Sato, Yoshikatsu; Kurihara, Daisuke; Suzaki, Takuya; Kawaguchi, Masayoshi; Maruyama, Daisuke; Higashiyama, Tetsuya

2017-11-01

Parasite infections cause dramatic anatomical and ultrastructural changes in host plants. Cyst nematodes are parasites that invade host roots and induce a specific feeding structure called a syncytium. A syncytium is a large multinucleate cell formed by cell wall dissolution-mediated cell fusion. The soybean cyst nematode (SCN), Heterodera glycines, is a major soybean pathogen. To investigate SCN infection and the syncytium structure, we established an in planta deep imaging system using a clearing solution ClearSee and two-photon excitation microscopy (2PEM). Using this system, we found that several cells were incorporated into the syncytium; the nuclei increased in size and the cell wall openings began to be visible at 2 days after inoculation (DAI). Moreover, at 14 DAI, in the syncytium developed in the cortex, there were thickened concave cell wall pillars that resembled "Parthenon pillars." In contrast, there were many thick board-like cell walls and rarely Parthenon pillars in the syncytium developed in the stele. We revealed that the syncytia were classified into two types based on the pattern of the cell wall structures, which appeared to be determined by the position of the syncytium inside roots. Our results provide new insights into the developmental process of syncytium induced by cyst nematode and a better understanding of the three-dimensional structure of the syncytium in host roots.

Mechanisms of pulmonary cyst pathogenesis in Birt-Hogg-Dube syndrome: The stretch hypothesis.

PubMed

Kennedy, John C; Khabibullin, Damir; Henske, Elizabeth P

2016-04-01

Loss-of-function mutations in the folliculin gene (FLCN) on chromosome 17p cause Birt-Hogg-Dube syndrome (BHD), which is associated with cystic lung disease. The risk of lung collapse (pneumothorax) in BHD patients is 50-fold higher than in the general population. The cystic lung disease in BHD is distinctive because the cysts tend to be basilar, subpleural and lentiform, differentiating BHD from most other cystic lung diseases. Recently, major advances in elucidating the primary functions of the folliculin protein have been made, including roles in mTOR and AMPK signaling via the interaction of FLCN with FNIP1/2, and cell-cell adhesion via the physical interaction of FLCN with plakophilin 4 (PKP4), an armadillo-repeat containing protein that interacts with E-cadherin and is a component of the adherens junctions. In addition, in just the last three years, the pulmonary impact of FLCN deficiency has been examined for the first time. In mouse models, evidence has emerged that AMPK signaling and cell-cell adhesion are involved in alveolar enlargement. In addition, the pathologic features of human BHD cysts have been recently comprehensively characterized. The "stretch hypothesis" proposes that cysts in BHD arise because of fundamental defects in cell-cell adhesion, leading to repeated respiration-induced physical stretch-induced stress and, over time, expansion of alveolar spaces particularly in regions of the lung with larger changes in alveolar volume and at weaker "anchor points" to the pleura. This hypothesis ties together many of the new data from cellular and mouse models of BHD and from the human pathologic studies. Critical questions remain. These include whether the consequences of stretch-induced cyst formation arise through a destructive/inflammatory program or a proliferative program (or both), whether cyst initiation involves a "second hit" genetic event inactivating the remaining wild-type copy of FLCN (as is known to occur in BHD-associated renal cell carcinomas), and whether cyst initiation involves exclusively the epithelial compartment versus an interaction between the epithelium and mesenchyme. Ultimately, understanding the mechanisms of cystic lung disease in BHD may help to elucidate the pathogenesis of primary spontaneous pneumothorax, with more than 20,000 cases reported annually in the United States alone. Copyright © 2016 Elsevier Ltd. All rights reserved.

Collagenase-3 expression in periapical lesions: an immunohistochemical study.

PubMed

Bhalla, G; Astekar, M S; Ramesh, G; Kaur, P; Sowmya, G V

2014-08-01

Collagenase-3 (matrix metalloproteinase-13) is a metalloproteinase (MMP) that is associated with bone lesions and exhibits variable expression patterns in odontogenic cysts; it may play a role in regulating focal proliferation and maturation of jaw cyst epithelium. We studied the localization, staining intensity and distribution of collagenase-3 in 13 periapical granulomas with epithelium, 16 periapical granulomas without epithelium and 10 radicular cysts using archived formalin fixed, paraffin embedded tissues. A monoclonal antibody against human collagenase-3 was used to evaluate its expression. Immunohistochemical staining intensities of collagenase-3 in all periapical lesions were (-), 4 (10%); (+), 1 (3%); (++), 22 (56%) and (+++), 12 (31%); differences were not statistically significant. Immunohistochemical distribution of collagenase-3 in epithelial cells was (-), 17 (44%); (+), 17 (44%); (++), 5 (13%); in fibroblasts it was (-), 8 (20%); (+), 23 (59%); (++), 8 (21%); in plasma cells it was (-), 7 (18%); (+), 22 (56%); (++), 10 (26%); in macrophages it was (-), 7 (18%); (+), and 15 (38%); and (++), 17 (44%). Statistically significant differences were found in epithelial cells (p = 0.00) and fibroblasts (p = 0.02), whereas differences were not statistically significant for plasma cells and macrophages. Collagenase-3 may play a role in the conversion of a periapical granuloma with epithelium to radicular cyst. MMP's influence not only epithelial rest cell migration, but also invasion of various stromal cells into granulomatous tissue.

Histologic and immunohistochemical characteristics of cutaneous cysts in Goltz-Gorlin syndrome: clues for differentiation of nonsyndromic cysts.

PubMed

Tirado, Mariantonieta; Ständer, Sonja; Metze, Dieter

2014-11-01

Goltz-Gorlin syndrome presents with multiple basal cell carcinomas, odontogenic keratocysts, and cutaneous cysts, among other manifestations. The cutaneous cysts have been described as both epidermoid cysts and keratocysts but were not further characterized. Light microscopic examinations were made on 23 cutaneous cysts in 4 patients associated with Goltz-Gorlin syndrome located on extremities, face, trunk, palms, and soles and compared with nonsyndromic vellus hair cysts, steatocystomas, and hybrid cysts. Twenty-one of the syndromic cysts revealed alternating infundibular-like and steatocystoma-like squamous epitheliums in varying proportions. The cysts were lined by both smooth and corrugated squamous epithelium. The horny layer was composed by alternating areas of thin, lamellate, and compact eosinophilic keratin. Only 2 cases showed an exclusive steatocystoma-like type of epithelium very similar to odontogenic keratocysts. Sebaceous glands and follicular structures were absent. There were no differences between palmar and plantar cysts and other anatomic locations. The ultrastructural findings in syndromatic cysts confirmed variable expression of keratohyalin granules. Only 3 of 6 cases of nonsyndromic hybrid cysts showed overlapping features with syndromic cysts. Immunohistochemical profiling of keratin, involucrin, filaggrin, loricrin, and BCL-2 expression in syndromatic cysts showed exclusive positivity of K19 and continuous staining for BCL-2. In summary, 2 types of cutaneous cysts are characteristic of Goltz-Gorlin, irrelevant of their anatomic location, namely steatocystoma-like and more frequently hybrid-like. The diagnosis of syndromic hybrid-like cysts should be considered whenever infundibular and steatocystoma differentiation alternate and overlap. Altogether, these findings in epithelial cysts may raise the suspicion of Goltz-Gorlin as an underlying cause.

Aneurysmal bone cyst and other nonneoplastic conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dahlin, D.C.; McLeod, R.A.

1982-08-01

Aneurysmal bone cyst is a benign proliferative tumefaction of bone. Histologic similarities indicate a kinship among classic aneurysmal bone cysts, essentially 'solid' proliferative lesions in bones; giant cell reparative granulomas of the jaws, at the base of the skull, and in the small bones of the hands and feet; skeletal lesions of hyperparathyroidism; and even pseudosarcomatous myositis ossificans, proliferative myositis, and proliferative fasciitis.

Mychonastes desiccatus Brown sp. nova (Chlorococcales, Chlorophyta)--an intertidal alga forming achlorophyllous desiccation-resistant cysts

NASA Technical Reports Server (NTRS)

Margulis, L.; Hinkle, G.; McKhann, H.; Moynihan, B.

1988-01-01

An intertidal Chlorella-like alga Mychonastes desiccatus Brown sp. nova, capable of forming achlorophyllous desiccation-resistant cysts, has been grown in unialgal culture. This small alga was first isolated from a dried sample of a well-studied microbial mat. The mat, located at North Pond, Laguna Figueroa, San Quintin, Baja California, Mexico, is a vertically-stratified microbial community which forms laminated sediments. Morphology, pigment composition and G+C content are within the range typical for the genus Chlorella s. 1. Unlike other chlorellae, however, upon desiccation M. desiccatus forms an achlorophyllous, lipid-filled cyst (thick-walled resting stage) in which no plastid is evident. Rewetting leads to chloroplast differentiation, excystment and recovery of the fully green alga. During desiccation, sporopollenin is deposited within a thickening cell wall. Encystment cannot be induced by growth in the dark. The formation of desiccation-induced cysts allows the alga to survive frequent and intermittent periods of dryness. These chlorellae tolerate wide ranges of acidity and temperature; they both grow and form cysts in media in which sodium ions are replaced with potassium. Although the cysts tolerate crystalline salts, the cell grow optimally in concentrations corresponding from three-quarters to full-strength seawater.

P53 Protein Expression in Dental Follicle, Dentigerous Cyst, Odontogenic Keratocyst, and Inflammatory Subtypes of Cysts: An Immunohistochemical Study

PubMed Central

Fatemeh, Mashhadiabbas; Sepideh, Arab; Sara, Bagheri Seyedeh; Nazanin, Mahdavi

2017-01-01

Objectives An odontogenic keratocyst (OKC) is a developmental odontogenic cyst with aggressive clinical behavior. This cyst shows a different growth mechanism from the more common dentigerous cyst and now has been renamed as a keratocystic odontogenic tumor (KCOT). Inflammation can assist tumor growth via different mechanisms including dysregulation of the p53 gene. This study aims to assess and compare the expression of tumor suppressor gene p53 in inflamed and non-inflamed types of OKC and dentigerous cyst. Methods Immunohistochemical expression of p53 was assessed in 14 cases of dental follicle, 34 cases of OKC (including 18 inflamed OKCs), and 31 cases of dentigerous cyst (including 16 inflamed cysts). Results The mean percentage of p53 positive cells was 0.7% in dental follicles, 5.4% in non-inflamed OKCs, 17.3% in inflamed OKCs, 1.2% in non-inflamed dentigerous cysts, and 2.2% in inflamed dentigerous cysts. The differences between the groups were statistically significant (p < 0.050) except for the difference between inflamed and non-inflamed dentigerous cysts, and between dental follicle and non-inflamed dentigerous cyst. Conclusions The difference in p53 expression in OKC and dentigerous cyst can explain their different growth mechanism and clinical behavior. Inflammation is responsible for the change in behavior of neoplastic epithelium of OKC via p53 overexpression. PMID:28584604

P53 Protein Expression in Dental Follicle, Dentigerous Cyst, Odontogenic Keratocyst, and Inflammatory Subtypes of Cysts: An Immunohistochemical Study.

PubMed

Fatemeh, Mashhadiabbas; Sepideh, Arab; Sara, Bagheri Seyedeh; Nazanin, Mahdavi

2017-05-01

An odontogenic keratocyst (OKC) is a developmental odontogenic cyst with aggressive clinical behavior. This cyst shows a different growth mechanism from the more common dentigerous cyst and now has been renamed as a keratocystic odontogenic tumor (KCOT). Inflammation can assist tumor growth via different mechanisms including dysregulation of the p53 gene. This study aims to assess and compare the expression of tumor suppressor gene p53 in inflamed and non-inflamed types of OKC and dentigerous cyst. Immunohistochemical expression of p53 was assessed in 14 cases of dental follicle, 34 cases of OKC (including 18 inflamed OKCs), and 31 cases of dentigerous cyst (including 16 inflamed cysts). The mean percentage of p53 positive cells was 0.7% in dental follicles, 5.4% in non-inflamed OKCs, 17.3% in inflamed OKCs, 1.2% in non-inflamed dentigerous cysts, and 2.2% in inflamed dentigerous cysts. The differences between the groups were statistically significant ( p < 0.050) except for the difference between inflamed and non-inflamed dentigerous cysts, and between dental follicle and non-inflamed dentigerous cyst. The difference in p53 expression in OKC and dentigerous cyst can explain their different growth mechanism and clinical behavior. Inflammation is responsible for the change in behavior of neoplastic epithelium of OKC via p53 overexpression.

Rac Regulates Giardia lamblia Encystation by Coordinating Cyst Wall Protein Trafficking and Secretion.

PubMed

Krtková, Jana; Thomas, Elizabeth B; Alas, Germain C M; Schraner, Elisabeth M; Behjatnia, Habib R; Hehl, Adrian B; Paredez, Alexander R

2016-08-23

Encystation of the common intestinal parasite Giardia lamblia involves the production, trafficking, and secretion of cyst wall material (CWM). However, the molecular mechanism responsible for the regulation of these sequential processes remains elusive. Here, we examined the role of GlRac, Giardia's sole Rho family GTPase, in the regulation of endomembrane organization and cyst wall protein (CWP) trafficking. Localization studies indicated that GlRac is associated with the endoplasmic reticulum (ER) and the Golgi apparatus-like encystation-specific vesicles (ESVs). Constitutive GlRac signaling increased levels of the ER marker PDI2, induced ER swelling, reduced overall CWP1 production, and promoted the early maturation of ESVs. Quantitative analysis of cells expressing constitutively active hemagglutinin (HA)-tagged GlRac (HA-Rac(CA)) revealed fewer but larger ESVs than control cells. Consistent with the phenotype of premature maturation of ESVs in HA-Rac(CA)-expressing cells, constitutive GlRac signaling resulted in increased CWP1 secretion and, conversely, morpholino depletion of GlRac blocked CWP1 secretion. Wild-type cells unexpectedly secreted large quantities of CWP1 into the medium, and free CWP1 was used cooperatively during cyst formation. These results, in part, could account for the previously reported observation that G. lamblia encysts more efficiently at high cell densities. These studies of GlRac show that it regulates encystation at several levels, and our findings support its coordinating role as a regulator of CWP trafficking and secretion. The central role of GlRac in regulating membrane trafficking and the cytoskeleton, both of which are essential to Giardia parasitism, further suggests its potential as a novel target for drug development to treat giardiasis. The encystation process is crucial for the transmission of giardiasis and the life cycle of many protists. Encystation for Giardia lamblia involves the assembly of a protective cyst wall via sequential production, trafficking, and secretion of cyst wall material. However, the regulatory pathways that coordinate cargo maturation and secretion remain unknown. Here, we asked whether the signaling activities of G. lamblia's single Rho family GTPase, GlRac, might have a regulatory role in the encystation process. We show that GlRac localizes to endomembranes and its signaling activities regulate the production of cyst wall protein 1 (CWP1), the maturation of encystation-specific vesicles (ESVs), and secretion of CWP1. We also show that secreted CWP1 is available for the development of cysts at the population level, a finding that in part could explain why Giardia encystation proceeds more efficiently at high cell densities. Copyright © 2016 Krtková et al.

Differential expression of Cyclin D1 in keratin-producing odontogenic cysts

PubMed Central

Vera-Sirera, Beatriz; Forner-Navarro, Leopoldo

2015-01-01

Objetives: The aim of the present study was to analyze the expression levels of Cyclin D1 (CCD1), a nuclear protein that plays a crucial role in cell cycle progression, in a series of keratin-producing odontogenic cysts. Study Design: A total of 58 keratin-producing odontogenic cysts, diagnosed over ten years and classified according to the WHO 2005 criteria, were immunohistochemically analyzed in terms of CCD1 expression, which was quantified in the basal, suprabasal and intermediate/superficial epithelial compartments. The extent of immunostaining was measured as a proportion of total epithelial thickness. Quantified immunohistochemical data were correlated with clinicopathological features and clinical recurrence. Results: Keratin-producing odontogenic cysts were classified as 6 syndromic keratocystic odontogenic tumors (S-KCOT), 40 sporadic or non-syndromic KCOT (NS-KCOT) and 12 orthokeratinized odontogenic cysts (OOC). Immunohistochemically, CCD1 staining was evident predominantly in the parabasal region of all cystic lesions, but among-lesion differences were apparent, showing a clear expansion of parabasal compartment especially in the S-KCOT, followed to a lesser extent in the NS-KCOT, and being much more reduced in the OOC, which had the greatest average epithelial thickness. Conclusions: The differential expression of CCD1 noted in the present study suggests that dysregulation of cell cycle progression from G1 to the S phase contributes to the different aggressiveness of these lesions. However, CCD1 expression levels did not predict NS-KCOT recurrence, which is likely influenced by factors unrelated to lesion biology. Key words:Keratin-producing odontogenic cyst, keratocyst, keratocystic odontogenic tumor, nevoid basal cell carcinoma syndrome, orthokeratinized odontogenic cyst, cyclin D1, immunohistochemistry. PMID:25475773

Biocidal efficacy of monochloramine against planktonic and biofilm-associated Naegleria fowleri cells.

PubMed

Goudot, S; Herbelin, P; Mathieu, L; Soreau, S; Banas, S; Jorand, F P A

2014-04-01

Free-living amoebae (FLA) in aqueous systems are a problem for water network managers and health authorities because some are pathogenic, such as Naegleria fowleri, and they have also been reported to operate as reservoirs and vectors of several pathogenic bacteria. Therefore, to better control the occurrence of such amoebae, we evaluate the efficacy of monochloramine against planktonic forms (trophozoites and cysts) and also biofilm-associated cells of N. fowleri as FLA are often associated with biofilms. From a freshwater biofilm growing in a pilot reactor and inoculated with N. fowleri, we obtained Ct values ranging from 4 to 17 mg Cl2 min l(-1) at 25°C and pH 8·2 on both planktonic and biofilm associated cells. In addition, the inactivation pattern of biofilm associated was intermediate between those of trophozoïtes and cysts. The monochloramine efficiency varies with the life stage of N. fowleri (trophozoïte, cyst, and biofilm-associated). The sensitivity to disinfectant of amoeba, that is, trophozoïtes and cysts, in the biofilm life stage is as high as that of their planktonic cyst form. This study gives Ct values for cysts and biofilm-associated N. fowleri. This may impact on water treatment strategies against amoebae and should be considered when controlling N. fowleri in man-made water systems such as cooling towers or hot water systems. © 2014 The Society for Applied Microbiology.

Distribution of macrophages and plasma cells in apical periodontitis and their relationship with clinical and image data

PubMed Central

Azeredo, Stéphane V.; Brasil, Sabrina C.; Antunes, Henrique; Marques, Fábio V.; Pires, Fábio R.

2017-01-01

Background Macrophages and plasma cells play a key role in the regulation of innate and adaptive immunity. The aim of this study was to assess the presence of these cells in apical periodontitis and their distribution comparing with clinical and image data. Material and Methods Thirty-three lesions were selected and divided in two groups (17 periapical cysts and 16 periapical granulomas). Immunoreactions using anti-CD68 and anti-CD138 antibodies were carried out; image analysis was performed with an optical microscope and 5 high-power fields from each slide were evaluated leading to an average score of immunoexpression. This mean score was compared between the two groups and correlated with the clinical and image data. Results There was no statistically significant difference (p >0.05) for the mean average score of CD68+ macrophages and CD138+ plasma cells when comparing the two groups (cysts x granulomas) and the specimens included in each specific group. No statistically significant differences (p >0.05) were also observed when comparing the average scores with clinical and image data. Conclusions The presence of CD68+ macrophages and CD138+ plasma cells was similar in periapical cysts and granulomas and the presence of these cells did not correlate with clinical and image data from both groups. Key words:Macrophages, plasma cells, apical periodontitis, periapical granuloma, periapical cyst. PMID:29075406

Damage-associated responses of the host contribute to defence against cyst nematodes but not root-knot nematodes.

PubMed

Shah, Syed Jehangir; Anjam, Muhammad Shahzad; Mendy, Badou; Anwer, Muhammad Arslan; Habash, Samer S; Lozano-Torres, Jose L; Grundler, Florian M W; Siddique, Shahid

2017-12-16

When nematodes invade and subsequently migrate within plant roots, they generate cell wall fragments (in the form of oligogalacturonides; OGs) that can act as damage-associated molecular patterns and activate host defence responses. However, the molecular mechanisms mediating damage responses in plant-nematode interactions remain unexplored. Here, we characterized the role of a group of cell wall receptor proteins in Arabidopsis, designated as polygalacturonase-inhibiting proteins (PGIPs), during infection with the cyst nematode Heterodera schachtii and the root-knot nematode Meloidogyne incognita. PGIPs are encoded by a family of two genes in Arabidopsis, and are involved in the formation of active OG elicitors. Our results show that PGIP gene expression is strongly induced in response to cyst nematode invasion of roots. Analyses of loss-of-function mutants and overexpression lines revealed that PGIP1 expression attenuates infection of host roots by cyst nematodes, but not root-knot nematodes. The PGIP1-mediated attenuation of cyst nematode infection involves the activation of plant camalexin and indole-glucosinolate pathways. These combined results provide new insights into the molecular mechanisms underlying plant damage perception and response pathways during infection by cyst and root-knot nematodes, and establishes the function of PGIP in plant resistance to cyst nematodes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Sex steroid receptors and apoptosis-related proteins are differentially expressed in polycystic ovaries of adult dogs.

PubMed

Chuffa, Luiz Gustavo de Almeida; Lupi Júnior, Luiz Antonio; da Maia Lima, Alfredo Feio

2016-02-01

In Polycystic Ovaries (PCOs), the dynamics of sex hormone receptors and follicle-related apoptotic signaling remain unknown. In this study, we investigated the expression of androgen receptors (AR), estrogen receptors (ERα and ERβ), and apoptosis-related molecules (BAX, active caspase-3, Bcl-2 and Survivin) on different follicular stages of PCOs in adult dogs. Clinical evidences of high estradiol and testosterone levels, persistent estrus and vaginal discharge were observed. Inhibin B immunolabeling was increased in primary and 2 to 5-mm follicles, and a marked epithelial hyperplasia was common in the ovarian surface. Ovarian epithelia and primary follicles showed low expression of AR, ERα, and ERβ, whereas a moderate immunoexpression of AR was found in theca cells of secondary follicles and cysts. In PCOs, growing follicles displayed ERα expression, and secondary follicles exhibited higher ERβ expression. In addition, while few ERα-positive cells were found in the cysts, ERβ was moderately expressed in growing follicles and cysts. BAX was upregulated in the ovarian epithelium, primary follicles, and in the wall of follicular cysts. Active caspase-3 was significantly downregulated in the epithelium, primary follicles, and follicular cysts, whereas growing follicles had a strong immunoexpression in the granulosa cells. Bcl-2 and survivin were increased in the epithelium and primary follicles, and only survivin was upregulated in secondary and growing follicles. While Bcl-2 had a diffuse immunexpression in the follicular cysts, survivin was overexpressed by these cells. We concluded that sex steroid receptors and apoptotic proteins are differentially expressed in the follicles of adult dogs with PCOs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Expression of p73 and TRAIL in odontogenic cysts and tumors.

PubMed

Mascitti, Marco; Santarelli, Andrea; Zizzi, Antonio; Procaccini, Maurizio; Lo Muzio, Lorenzo; Rubini, Corrado

2016-01-01

Odontogenic tumors are a group of lesions arising from the odontogenic apparatus. Although the mechanism of oncogenesis and tumor progression in these lesions remains unknown, certain proteins, such as those involved in apoptosis, seem to be involved in the differentiation and proliferation of odontogenic epithelial cells. The aim of this study was to analyze the expression of p73 and TNF-related apoptosis-inducing ligand (TRAIL) in odontogenic tumors and cysts, and to clarify changes in the expression of these proteins. Immunohistochemical analysis was performed on 21 ameloblastomas, 15 keratocystic odontogenic tumors and 15 dentigerous cysts. We carried out quantitative assessment of p73 and TRAIL expression by determining the percentages of positive cells on a continuous scale. Five cases of orthokeratinized odontogenic cyst were also examined. The percentages of cells immunohistochemically positive for p73 were 52.6 ± 25.4% in ameloblastomas, 76.0 ± 13.1% in keratocystic odontogenic tumors, and 26.7 ± 30.7% in odontogenic cysts, whereas the corresponding figures for TRAIL were 57.6 ± 16.1%, 8.9 ± 10.0%, and 1.5 ± 0.5%, respectively. Imbalance of the apoptosis pathway, with dysregulation of p73 and TRAIL, seems to play a role in the oncogenesis of odontogenic tumors.(J Oral Sci 58, 459-464, 2016).

Dynamics of Alexandrium fundyense blooms and shellfish toxicity in the Nauset Marsh System of Cape Cod (Massachusetts, USA)

PubMed Central

Crespo, Bibiana G.; Keafer, Bruce A.; Ralston, David K.; Lind, Henry; Farber, Dawson; Anderson, Donald M.

2017-01-01

Paralytic Shellfish Poisoning (PSP) toxins are annually recurrent along the Massachusetts coastline (USA), which includes many small embayments and salt ponds. Among these is the Nauset Marsh System (NMS), which has a long history of PSP toxicity. Little is known, however, about the bloom dynamics of the causative organism Alexandrium fundyense within that economically and socially important system. The overall goal of this work was to characterize the distribution and dynamics of A. fundyense blooms within the NMS and adjacent coastal waters by documenting the distribution and abundance of resting cysts and vegetative cells. Cysts were found predominantly in three drowned kettle holes or salt ponds at the distal ends of the NMS – Salt Pond, Mill Pond, and Town Cove. The central region of the NMS had a much lower concentration of cysts. Two types of A. fundyense blooms were observed. One originated entirely within the estuary, seeded by cysts in the three seedbeds. These blooms developed independently of each other and of the A. fundyense population observed in adjacent coastal waters outside the NMS. The temporal development of the blooms was different in the three salt ponds, with initiation differing by as much as 30 days. These differences do not appear to reflect the initial cyst abundances in these locations, and may simply result from higher cell retention and higher nutrient concentrations in Mill Pond, the first site to bloom. Germination of cysts accounted for a small percentage of the peak cell densities in the ponds, so population size was influenced more by the factors affecting growth than by cyst abundance. Subsurface cell aggregation (surface avoidance) limited advection of the vegetative A. fundyense cells out of the salt ponds through the shallow inlet channels. Thus, the upper reaches of the NMS are at the greatest risk for PSP since the highest cyst abundances and cell concentrations were found there. After these localized blooms in the salt ponds peaked and declined, a second, late season bloom occurred within the central portions of the NMS. The timing of this second bloom relative to those within the salt ponds and the coastal circulation patterns at that time strongly suggest that those cells originated from a regional A. fundyense bloom in the Gulf of Maine, delivered to the central marsh from coastal waters outside the NMS through Nauset Inlet. These results will guide policy decisions about water quality as well as shellfish monitoring and utilization within the NMS and highlight the potential for “surgical” closures of shellfish during PSP events, leaving some areas open for harvesting while others are closed. PMID:28690476

Suspended Alexandrium spp. hypnozygote cysts in the Gulf of Maine

NASA Astrophysics Data System (ADS)

Kirn, Sarah L.; Townsend, David W.; Pettigrew, Neal R.

2005-09-01

The life cycle of dinoflagellates of the genus Alexandrium includes sexual reproduction followed by the formation of a dormant hypnozygote cyst, which serves as a resting stage. Negatively buoyant cysts purportedly fall to the benthos where they undergo a mandatory period of quiescence. Previous reports of cysts in the surficial sediments of the Gulf of Maine, where Alexandrium blooms are well documented, show a broad distribution of cysts, with highest concentrations generally in sediments below 100 m depth. We report here an exploration of cysts suspended in the water column, where they would be better positioned to inoculate springtime Alexandrium populations. During cruises in February, April, and June of 2000, water samples were collected at depths just off the bottom (within 5 m), at the top of the bottom nepheloid layer, and near the surface (1 m) and examined for cyst concentrations. Suspended cysts were found throughout the Gulf of Maine and westernmost Bay of Fundy. Planktonic cyst densities were generally greater in near-bottom and top of the bottom nepheloid layer samples than in near-surface water samples; densities were of the order of 10 2 cysts m -3 in surface waters, and 10 2-10 3 cysts m -3 at near-bottom depths. Temporally, they were most abundant in February and least abundant in April. Reports by earlier workers of cysts in the underlying sediments were on the order of 10 3 cysts cm -3. We present calculations that demonstrate the likelihood of cyst resuspension from bottom sediments forced by swell and tidal currents, and propose that such resuspended cysts are important in inoculating the seasonal bloom. We estimate that suspended cysts may contribute significantly to the annual vegetative cell population in the Gulf of Maine.

Macronuclear chromatin structure dynamics in Colpoda inflata (Protista, Ciliophora) resting encystment.

PubMed

Tiano, L; Chessa, M G; Carrara, S; Tagliafierro, G; Delmonte Corrado, M U

1999-01-01

The chromatin structure dynamics of the Colpoda inflata macronucleus have been investigated in relation to its functional condition, concerning chromatin body extrusion regulating activity. Samples of 2- and 25-day-old resting cysts derived from a standard culture, and of 1-year-old resting cysts derived from a senescent culture, were examined by means of histogram analysis performed on acquired optical microscopy images. Three groups of histograms were detected in each sample. Histogram classification, clustering and matching were assessed in order to obtain the mean histogram of each group. Comparative analysis of the mean histogram showed a similarity in the grey level range of 25-day- and 1-year-old cysts, unlike the wider grey level range found in 2-day-old cysts. Moreover, the respective mean histograms of the three cyst samples appeared rather similar in shape. All this implies that macronuclear chromatin structural features of 1-year-old cysts are common to both cyst standard cultures. The evaluation of the acquired images and their respective histograms evidenced a dynamic state of the macronuclear chromatin, appearing differently condensed in relation to the chromatin body extrusion regulating activity of the macronucleus. The coexistence of a chromatin-decondensed macronucleus with a pycnotic extrusion body suggests that chromatin unable to decondense, thus inactive, is extruded. This finding, along with the presence of chromatin structural features common to standard and senescent cyst populations, supports the occurrence of 'rejuvenated' cell lines from 1-year-old encysted senescent cells, a phenomenon which could be a result of accomplished macronuclear renewal.

Oral foregut cyst in a neonate.

PubMed

Rosa, Ana Cláudia Garcia; Hiramatsu, Daniel Martins; de Moraes, Fábio Roberto Ruiz; Passador-Santos, Fabrício; de Araújo, Vera Cavalcanti; Soares, Andresa Borges

2013-11-01

Oral foregut cysts are congenital choristomas that arise in the oral cavity during embryonic development from remnants of foregut-derived epithelium. This is an unusual report of a neonate with a large congenital sublingual cystic lesion, extending superficially from the left ventral tongue to the anterior floor of the mouth, impeding breast-feeding. The differential diagnosis included dermoid cyst, epidermoid cyst, mucous retention cyst, and oral lymphangioma. The treatment of choice was enucleation under general anesthesia. Histology showed a cystic lesion with a ciliated pseudostratified columnar epithelium with numerous goblet cells. Immunohistochemistry was positive for cytokeratin 7 and thyroid transcription factor 1 and negative for cytokeratin 20, resulting in a final diagnosis of an oral foregut cyst. Three weeks after surgery, the tongue had healed with good mobility, and breast-feeding could be established. No recurrence was present at 6 months of follow-up.

Comparision of Immunohistochemical Expression of CD10 in Odontogenic Cysts

PubMed Central

Munisekhar, M.S.; Suri, Charu; Rajalbandi, Santosh Kumar; M.R., Pradeep; Gothe, Pavan

2014-01-01

Background: Expression of CD10 has been documented in various tumors like nasopharyngeal carcinoma, gastric carcinoma, squamous cell carcinoma, odontogenic tumors. Aim: To evaluate and compare CD10 expression in odontogenic cysts like radicular cyst, dentigerous cyst and odontogenic keratocyst (OKC). Materials and Methods: Total 60 cases were included in the study, comprising 20 cases each of radicular, dentigerous and odontogenic keratocyst. Each case was evaluated and compared for immunohistochemical expression of CD10. Results obtained were statistically analysed using ANOVA test followed by post hoc test Tukey-Kramer Multiple Comparisons Test for continuous variable and Chi-square test for discrete variable. Results: More number of cases showing sub-epithelial stromal CD10 expression were found in OKC among the cysts. Conclusion: CD10 expression was more in OKC compared to radicular and dentigerous cysts. PMID:25584313

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vilches, J.; Lopez, A.; Martinez, M.C.

This paper discusses the value of scanning electron microscopy (SEM) and x-ray microanalysis in the classification of craniopharyngiomas. This neoplasm shows epithelial nest, cords of cuboid cells, foci of squamous metaplasia, and microcystic degeneration. SEM reveals that the epithelial cysts are lined with elongated cells that possess numerous microvilli and blebs and that some cysts are lined with polyhedral cells. The microvilli are interpreted as characteristic of the fast growing craniopharyngiomas. A microanalytical study of the calcified areas reveals the presence of magnesium, phosphorus, and calcium.

Seborrheic inclusion cyst of the skin positive for cytoplasmic inclusion bodies and HPV antigen.

PubMed

Terada, Tadashi

2012-01-01

Seborrheic inclusion cyst (SIC) is a very rare variant of epidermal cyst of the skin. SIC shows seborrheic keratosis (SK)-like lesion in epidermal cyst. SIC is extremely rare; only 6 case reports have been published in the English literature. However, no immunohistochemical study of SIC has been reported. A 41-year-old Japanese man noticed a subcutaneous tumor in the neck. Physical examination showed slightly mobile tumor in the subcutaneous tissue, and total excision was performed. Grossly, the tumor (1 x 1 x 0.8 cm) was cyst containing atheromatous keratin. Microscopically, the lesion is a cyst containing keratins. About one half of the cyst showed features of epidermal cyst consisting of mature squamous epithelium with granular layers. The other one half showed SK-like epidermal proliferation. The SK-like area showed basaloid cell proliferation with pseudohorn cysts. No significant atypia was noted. Many eosinophilic cytoplasmic inclusion bodies were noted in the SK-like area. Immunohistochemically, the SK-like area was positive for pancytokeratin AE1/3, pancytokeratin CAM5.2, p63, and Ki-67 (labeling=8%) and HPV, but negative for p53. The pathological diagnosis was SIC.

Sedimentary Records of Harmful Bloom-Producing Dinoflagellates from Alvarado Lagoon (Southwestern Gulf of Mexico)

NASA Astrophysics Data System (ADS)

Limoges, A.; Mertens, K. N.; ruiz-Fernandez, A. C.; Sánchez Cabeza, J. A.; de Vernal, A.

2014-12-01

Organic-walled dinoflagellate cyst assemblages were studied from a sediment core collected in Alvarado Lagoon (southwestern Gulf of Mexico) in order to evaluate their use as tracers of toxic algal blooms. The sedimentary record spans the last ~560 years (CE) and shows high abundances of Polysphaeridium zoharyi, the cyst of the dinoflagellate Pyrodinium bahamense, which is known to cause toxic blooms. Cyst fluxes in the sediment of the Alvarado lagoon suggest frequent blooms of Pyrodinium bahamense in the past hundreds of years. Moreover, the high concentrations of the cysts (~ 4000 cysts g-1) in the "modern" surface sediment reveal that the area is susceptible to be affected by future blooms, especially during seasons of heavy rain and wind, when cysts are resuspended in the water column. The dinoflagellate cyst bank in sediment deserves special attention as it may constitute a source for the export of cells in adjacent regions. The cyst of other harmful dinoflagellates have been recovered in the sediment. They notably include those of the benthic dinoflagellate Bysmatrum subsalsum, which is here reported for the first time.

NCAM (CD56) expression in keratin-producing odontogenic cysts: aberrant expression in KCOT.

PubMed

Vera-Sirera, Beatriz; Forner-Navarro, Leopoldo; Vera-Sempere, Francisco

2015-02-12

To investigate immunohistochemically the expression of neural cell adhesion molecule (NCAM), which has been identified as a signaling receptor with frequent reactivity in ameloblastomas (AB), in a series of keratin-producing odontogenic cysts (KPOCs). Immunohistochemical expression of NCAM, using a monoclonal antibody, was determined in a series of 58 KPOCs comprising 12 orthokeratinized odontogenic cysts (OOCs) and 46 keratocystic odontogenic tumors (KCOTs), corresponding to 40 non-syndromic KCOT (NS-KCOTs) and 6 syndromic KCOT (S-KCOTs), associated with nevic basocellular syndrome (NBCS). NCAM expression was negative in all OOCs, but 36.45% of KCOTs exhibited focal and heterogeneous expression at the basal cell level, as well as in basal budding areas and the basal cells of daughter cysts. The latter two locations were especially applicable to S-KCOTs, with focal NCAM reactivity occurring in 66.66% of cases. Aberrant NCAM expression, in KCOTs but especially in S-KCOTs, together with its immunomorphological location, suggests that this adhesion molecule and signaling receptor plays a role in the pathogenesis of KCOTs, with a probable impact on lesional recurrence.

A case of epidermal cyst with pilomatrical differentiation.

PubMed

Ikoma, Norihiro; Iwashita, Kenichi; Umezawa, Yoshinori; Matsuyama, Takashi; Ohta, Yukinori; Ozawa, Akira; Umemura, Shinobu; Ueyama, Yoshito; Yamazaki, Hitoshi

2004-09-01

A 20-year-old Japanese woman with an epidermal cyst on the back is described. Physical examination revealed a deep blue and round shaped cystic lesion measuring 10 min in diameter. A comedo-like keratotic plug also could be seen at the center. Histologically, the inner surface of the cyst was clearly separated of two types of the cells. The one was layers of epidermal keratinocytes and the other looked like a basal layer of epidermis, which immunohistochemically stained by S-100, HMB-45, cytokeratin (CK19) and Fontana-Masson staining. We diagnosed this case as epidermal cyst with pilomatrical differentiation.

Imaging of cerebellopontine angle lesions: an update. Part 2: intra-axial lesions, skull base lesions that may invade the CPA region, and non-enhancing extra-axial lesions.

PubMed

Bonneville, Fabrice; Savatovsky, Julien; Chiras, Jacques

2007-11-01

Computed tomography (CT) and magnetic resonance (MR) imaging reliably demonstrate typical features of vestibular schwannomas or meningiomas in the vast majority of mass lesions responsible for cerebellopontine angle (CPA) syndrome. However, a large variety of unusual lesions can also be encountered in the CPA. Covering the entire spectrum of lesions potentially found in the CPA, these articles explain the pertinent neuroimaging features that radiologists need to know to make clinically relevant diagnoses in these cases, including data from diffusion- and perfusion-weighted imaging or MR spectroscopy, when available. A diagnostic algorithm based on the lesion's site of origin, shape and margins, density, signal intensity and contrast material uptake is also proposed. Non-enhancing extra-axial CPA masses are cystic (epidermoid cyst, arachnoid cyst, neurenteric cyst) or contain fat (dermoid cyst, lipoma). Tumours can also extend into the CPA by extension from the skull base (paraganglioma, chondromatous tumours, chordoma, cholesterol granuloma, endolymphatic sac tumour). Finally, brain stem or ventricular tumours can present with a significant exophytic component in the CPA that may be difficult to differentiate from an extra-axial lesion (lymphoma, hemangioblastoma, choroid plexus papilloma, ependymoma, glioma, medulloblastoma, dysembryoplastic neuroepithelial tumour).

Viability and morphological changes of Acanthamoeba spp. cysts after treatment with Effective microorganisms (EM).

PubMed

Sampaotong, Tanitta; Lek-Uthai, Usa; Roongruangchai, Jantima; Roongruangchai, Kosol

2016-06-01

Acanthamoeba is a free-living opportunistic protozoan parasite that is found in diverse environments. It can cause keratitis, mostly related to inappropriate use of contact lenses, as well as life threatening diseases including encephalitis, disseminated sinusitis, and skin ulcers. This study investigated morphological changes and fine structures of the cyst form of Acanthamoeba spp. after treatment with effective microorganisms (EM™) using light and scanning electron microscopies. Acanthamoeba cysts treated with 1:2, 1:4, 1:6, and undiluted EM™ showed higher percentages of non-viable cysts than those treated with 1:8, 1:10, 1:100, 1:200, and 1:400 EM™ and at 5 days post-treatment developed from cystic stage to trophozoite stage. Acanthamoeba cysts treated at concentrations of 1:2, 1:4, 1:6, and undiluted EM™ exhibited cytoplasmic clumping and shrinkage of amoeba cells away from cyst walls. The effective EM™ concentration lethal to Acanthamoeba spp. cyst could provide information to monitor the environmental control system.

Epidermoid cyst of the spleen

PubMed Central

Vo, Quoc Duy; Monnard, Etienne; Hoogewoud, Henri Marcel

2013-01-01

We report the case of a patient with a palpable mass and abdominal pain in the left upper quadrant. A physical examination revealed tenderness in this region. An ultrasound performed initially showed a large cystic structure. A CT examination revealed a large cyst originating in the spleen with loculations in its upper part and focal calcification in the wall. On MRI, the cystic mass showed high signal on T1-weighted and T2-weighted images. The carbohydrate antigen 19-9 (CA 19-9) was measured at 88 U/ml (standard <37.1 mUI/l). According to the imaging examinations and laboratory tests performed, it was impossible to determine if the splenic cyst was parasitic or non-parasitic. Given the most important risks of complications encountered in parasitic cysts, it was decided to treat this splenic cyst as a parasitic cyst. For this reason, an elective laparoscopic splenectomy with preoperative embolisation of the splenic artery was performed. The histological diagnosis was a primary epidermoid splenic cyst with inner lining epithelial cells. PMID:23667225

Zinc in Entamoeba invadens.

NASA Technical Reports Server (NTRS)

Morgan, R. S.; Sattilaro, R. F.

1972-01-01

Atomic absorption spectroscopy, electron microprobe analysis, and dithizone staining of trophozoites and cysts of Entamoeba invadens demonstrate that these cells have a high concentration of zinc (approximately one picogram per cell or 1% of their dry weight). In the cysts of this organism, the zinc is confined to the chromatoid bodies, which previous work has shown to contain crystals of ribosomes. The chemical state and function of this zinc are unknown.

TGFbeta receptor saxophone non-autonomously regulates germline proliferation in a Smox/dSmad2-dependent manner in Drosophila testis.

PubMed

Li, Chun-Yan; Guo, Zheng; Wang, Zhaohui

2007-09-01

Elucidating the regulatory mechanism of cell proliferation is central to the understanding of cancer development or organ size control. Drosophila spermatogenesis provides an excellent model to study cell proliferation since the germline cells mitotically amplify in a precise manner. However, the underlying molecular mechanism remains elusive. Germ cells derived from each gonialblast develop synchronously as one unit encapsulated by two somatic support cells (called cyst cells). Components of TGFbeta pathway have previously been found to restrict germ cell proliferation via their functions in cyst cells. Here we report that saxophone (sax), a TGFbeta type I receptor, is required in somatic cells to prevent the mitotically dividing spermatogonia from over-amplifying. Using various approaches, we demonstrate that Mad (Mothers against Dpp), a receptor-Smad usually associated with Sax-mediated TGFbeta/BMP signaling, is dispensable in this process. Instead, Smox (Smad on X, Drosophila Smad2), the other receptor-Smad formerly characterized in TGFbeta/activin signaling, is necessary for the precise mitotic divisions of spermatogonia. Furthermore, over-expressing Smox in cyst cells can partially rescue the proliferation phenotype induced by sax mutation. We propose that Smox acts downstream of Sax to prevent spermatogonial over-proliferation in Drosophila.

Possible Estrogen Dependency in the Pathogenesis of Branchial Cleft Cysts.

PubMed

Raguse, Jan D; Anagnostopoulos, Ioannis; Doll, Christian; Heiland, Max; Jöhrens, Korinna

2017-01-01

Even though branchial cleft cysts are currently accepted as a congenital anomaly, there is often a long delay until clinical presentation; branchial cleft cysts classically appear in the second to fourth decade of life. Our observation of their occurrence in three pregnant women encouraged us to contemplate a possible hormonal influence. Immunohistological analysis was performed for the evaluation of the estrogen receptor alpha (ER α ) in paraffin-embedded tissue specimens of 16 patients with a diagnosis of branchial cleft cyst, with three of them being pregnant. Expression of ER α was detected within epithelial cells only in branchial cleft cysts in pregnant females; moreover, higher growth fractions (Ki-67/Mib1) were found. The fact that the estrogen receptor was expressed only in pregnant women, in contrast to 13 investigated cases, may suggest that the high level of estrogen in pregnancy is a possible explanation for the spontaneous growth of branchial cleft cysts.

Possible Estrogen Dependency in the Pathogenesis of Branchial Cleft Cysts

PubMed Central

Raguse, Jan D.; Jöhrens, Korinna

2017-01-01

Background Even though branchial cleft cysts are currently accepted as a congenital anomaly, there is often a long delay until clinical presentation; branchial cleft cysts classically appear in the second to fourth decade of life. Our observation of their occurrence in three pregnant women encouraged us to contemplate a possible hormonal influence. Methods Immunohistological analysis was performed for the evaluation of the estrogen receptor alpha (ERα) in paraffin-embedded tissue specimens of 16 patients with a diagnosis of branchial cleft cyst, with three of them being pregnant. Results Expression of ERα was detected within epithelial cells only in branchial cleft cysts in pregnant females; moreover, higher growth fractions (Ki-67/Mib1) were found. Conclusion The fact that the estrogen receptor was expressed only in pregnant women, in contrast to 13 investigated cases, may suggest that the high level of estrogen in pregnancy is a possible explanation for the spontaneous growth of branchial cleft cysts. PMID:29410959

Laparoscopic management of peripelvic renal cysts: University of California, San Francisco, experience and review of literature.

PubMed

Camargo, Affonso H L A; Cooperberg, Matthew R; Ershoff, Brent D; Rubenstein, Jonathan N; Meng, Maxwell V; Stoller, Marshall L

2005-05-01

To report our experience and review published reports on the laparoscopic management of peripelvic renal cysts. Peripelvic renal cysts represent a unique subset of renal cysts, as they are rare, commonly symptomatic, and more difficult to treat than simple peripheral renal cysts. Minimally invasive methods for the treatment of peripelvic renal cysts, including laparoscopic decortication, have recently become more common. Four patients who presented with symptomatic peripelvic cysts underwent laparoscopic decortication at our institution. All four were men aged 47 to 65 years. One patient had undergone an unsuccessful prior cyst aspiration. All patients underwent preoperative computed tomography and retrograde pyelography. The mean number of peripelvic cysts per patient was 3.0, and the mean cyst size was 7.1 cm. The mean operative time was 259 minutes (range 240 to 293), and the mean estimated blood loss was 30 mL (range 10 to 50). No evidence of cystic renal cell carcinoma was found on aspiration cytology or cyst wall pathologic examination. The mean hospital stay was 1.3 days. No inadvertent collecting system injuries and no intraoperative or postoperative complications occurred. All 4 patients achieved symptomatic relief and were determined to have radiologic success as determined by the 6-month postoperative computed tomography findings. Laparoscopic ablation of peripelvic renal cysts is more difficult than that of simple peripheral renal cysts and demands a heightened awareness of potential complications and, therefore, more advanced surgical skills. In addition to our experience, a thorough review of published reports found this procedure to be safe and effective with appropriate patient selection.

Spatial and temporal variability of Alexandrium cyst fluxes in the Gulf of Maine: Relationship to seasonal particle export and resuspension.

PubMed

Pilskaln, C H; Anderson, D M; McGillicuddy, D J; Keafer, B A; Hayashi, K; Norton, K

2014-05-01

Quantification of Alexandrium cyst fluxes through the Gulf of Maine water column is central to understanding the linkage between the source and fate of annual Alexandrium blooms in the offshore waters. These blooms often lead to paralytic shellfish poisoning (PSP) and extensive closures of shellfish beds. We report here on time-series sediment trap deployments completed at four offshore locations in the gulf between 2005 and 2010 as components of two ECOHAB-GOM field programs. Data presented documents the substantial spatial and temporal fluctuations in Alexandrium fundyense cyst fluxes in the gulf. Cyst delivery out of the euphotic zone peaked primarily between July and August following annual spring-summer Alexandrium blooms and was greatest in the western gulf. At all sites, cyst flux maxima to the subsurface waters were rarely coincident with seasonal peaks in the total mass export of particulate material indicating that cyst delivery was primarily via individually sinking cysts. Where persistent benthic nepheloid layers (BNLs) exist, significant sediment resuspension input of cysts to the near-bottom water column was evidenced by deep cyst fluxes that were up to several orders of magnitude greater than that measured above the BNL. The largest cyst fluxes in the BNL were observed in the eastern gulf, suggesting greater resuspension energy and BNL cyst inventories in this region. Temporal similarities between peak cyst export out of the upper ocean and peak cyst fluxes in the BNL were observed and document the contribution of seasonal, newly formed cysts to the BNL. The data however also suggest that many Alexandrium cells comprising the massive, short-lived blooms do not transition into cysts. Time-series flow measurements and a simple 1D model demonstrate that the BNL cyst fluxes reflect the combined effects of tidal energy-maintained resuspension, deposition, and input of cysts from the overlying water column.

Spatial and temporal variability of Alexandrium cyst fluxes in the Gulf of Maine: Relationship to seasonal particle export and resuspension

PubMed Central

Pilskaln, C.H.; Anderson, D.M.; McGillicuddy, D.J.; Keafer, B.A.; Hayashi, K.; Norton, K.

2014-01-01

Quantification of Alexandrium cyst fluxes through the Gulf of Maine water column is central to understanding the linkage between the source and fate of annual Alexandrium blooms in the offshore waters. These blooms often lead to paralytic shellfish poisoning (PSP) and extensive closures of shellfish beds. We report here on time-series sediment trap deployments completed at four offshore locations in the gulf between 2005 and 2010 as components of two ECOHAB–GOM field programs. Data presented documents the substantial spatial and temporal fluctuations in Alexandrium fundyense cyst fluxes in the gulf. Cyst delivery out of the euphotic zone peaked primarily between July and August following annual spring–summer Alexandrium blooms and was greatest in the western gulf. At all sites, cyst flux maxima to the subsurface waters were rarely coincident with seasonal peaks in the total mass export of particulate material indicating that cyst delivery was primarily via individually sinking cysts. Where persistent benthic nepheloid layers (BNLs) exist, significant sediment resuspension input of cysts to the near-bottom water column was evidenced by deep cyst fluxes that were up to several orders of magnitude greater than that measured above the BNL. The largest cyst fluxes in the BNL were observed in the eastern gulf, suggesting greater resuspension energy and BNL cyst inventories in this region. Temporal similarities between peak cyst export out of the upper ocean and peak cyst fluxes in the BNL were observed and document the contribution of seasonal, newly formed cysts to the BNL. The data however also suggest that many Alexandrium cells comprising the massive, short-lived blooms do not transition into cysts. Time-series flow measurements and a simple 1D model demonstrate that the BNL cyst fluxes reflect the combined effects of tidal energy-maintained resuspension, deposition, and input of cysts from the overlying water column. PMID:25431527

Cyst fluid telomerase activity predicts the histologic grade of cystic neoplasms of the pancreas

PubMed Central

Hata, Tatsuo; Molin, Marco Dal; Suenaga, Masaya; Yu, Jun; Pittman, Meredith; Weiss, Matthew; Canto, Marcia I.; Wolfgang, Christopher; Lennon, Anne Marie; Hruban, Ralph H; Goggins, Michael

2016-01-01

Purpose Pancreatic cysts frequently pose clinical dilemmas. On one hand, cysts with high-grade dysplasia offer opportunities for cure, on the other hand, those with low-grade dysplasia are easily over treated. Cyst fluid markers have the potential to improve the evaluation of these cysts. Since telomerase activity is commonly activated in malignant cells, we evaluated the diagnostic performance of cyst fluid telomerase activity measurements for predicting histologic grade. Experimental design Telomerase activity was measured using telomerase repeat amplification with digital-droplet PCR in surgically-aspirated cyst fluid samples from 219 patients who underwent pancreatic resection for a cystic lesion (184, discovery, 35 validation) and 36 patients who underwent endoscopic ultrasound fine needle aspiration. Methodological and clinical factors associated with telomerase activity were examined. Results Telomerase activity was reduced in samples that had undergone prior thawing. Among 119 samples not previously thawed, surgical cyst fluids from cystic neoplasms with high-grade dysplasia +/− associated invasive cancer had higher telomerase activity (median [interquartile range], 1158 [295.9–13033] copies/μL of cyst fluid than those without (19.74 [2.58–233.6] copies/μL) (P < 0.001). Elevated cyst fluid telomerase activity had a diagnostic accuracy for invasive cancer/high-grade dysplasia of 88.1% (discovery), 88.6% (validation), and 88.2% (merged). Among cysts classified preoperatively as having “worrisome features”, cyst fluid telomerase activity had high diagnostic performance (sensitivity 73.7%, specificity 90.6%, accuracy, 86.1%). In multivariate analysis, telomerase activity independently predicted the presence of invasive cancer/high-grade dysplasia. Conclusion Cyst fluid telomerase activity can be a useful predictor of the neoplastic grade of pancreatic cysts. PMID:27230749

Solid sand particle addition can enhance the production of resting cysts in dinoflagellates

NASA Astrophysics Data System (ADS)

Yang, Aoao; Hu, Zhangxi; Tang, Yingzhong

2018-03-01

Resting cysts are an important part of the life cycle for many harmful algal bloom-forming dinoflagellates, and play vital roles in the recurrence and geographical spread of harmful algal blooms. Numerous factors have been suggested to regulate the formation of resting cysts, although only a few have been proven to be significant. Cyst formation can be induced by adverse environmental conditions such as drastic changes in temperature, light, salinity, and nutrient levels, and by biological interactions. In this study, we evaluated the ability of an artificial factor (fine sand particles) to enhance the formation of resting cysts. Fine sand particles were added to cultures of dinoflagellates that are known to produce cysts. The addition of fine sand particles significantly increased both the production rate and final yield of cysts in cultures of Scrippsiella trochoidea, Biecheleria brevisulcata, and Levanderina fissa (= Gymnodinium fissum, Gyrodinium instriatum, Gyrodinium uncatenum). The largest increase in the final yield (107-fold) of cysts as a result of sand addition was in S. trochoidea. However, addition of fine sand particles did not induce cyst formation, or barely affected cyst formation, in Akashiwo sanguinea, Cochlodinium polykrikoides and Pheopolykrikos hartmannii, which are also known to be cyst-producing species. We speculated that addition of sand significantly increased the chances of cell collision, which triggered cyst formation. However, further research is required to test this idea. Importantly, our findings indicate that the addition of fine sand particles is a useful method to obtain a large quantity of cysts in a short time for laboratory studies or tests; for example, if a cyst viability test is being used to assess the effectiveness of ships' ballast water treatment.

Alexandrium minutum resting cyst distribution dynamics in a confined site

NASA Astrophysics Data System (ADS)

Anglès, Sílvia; Jordi, Antoni; Garcés, Esther; Basterretxea, Gotzon; Palanques, Albert

2010-02-01

The life cycle of the toxic dinoflagellate Alexandrium minutum consists of an asexual stage, characterized by motile vegetative cells, and a sexual stage, a resting cyst that once formed remains dormant in the sediment. Insight into the factors that determine the distribution and abundance of resting cysts is essential to understanding the dynamics of the vegetative phase. In investigations carried out between January 2005 and January 2008 in Arenys de Mar harbor (northwestern Mediterranean Sea), the spatial and temporal distribution patterns of A. minutum resting cysts and of the sediments were studied during different bloom stages of the vegetative population. Maximum cyst abundance was recorded mainly in the innermost part of the harbor while the lowest abundance always occurred near the harbor entrance, consistent with the distribution of silt-clay sediment fractions. The tendency of cysts in sediments to increase after bloom periods was clearly associated with new cyst formation, while cyst abundance decreased during non-bloom periods. Exceptions to this trend were observed in stations dominated by the deposition of coarse sediments. High correlation between the presence of cysts and clays during non-bloom periods indicates that cysts behave as passive sediment particles and are influenced by the same hydrodynamic processes as clays. In Arenys de Mar, the main physical forcing affecting sediment resuspension is the seiche, which was studied using in situ measurements and numerical models to interpret the observed distribution patterns. During non-bloom periods, cyst losses were smaller when the seiche was more active and at the station where the seiche-induced current was larger. Thus, seiche-forced resuspension appears to reduce cyst losses by reallocating cysts back to the sediment surface such that their burial in the sediment is avoided. The observed vertical profiles of the cysts were consistent with this process.

Analysis of the frequency and nature of hyaline ring granulomas in inflammatory odontogenic cysts.

PubMed

Henriques, A C G; Pereira, J S; Nonaka, C F W; Freitas, R A; Pinto, L P; Miguel, M C C

2013-01-01

To determine the prevalence of hyaline ring granulomas (HRGs) in a large case series of inflammatory odontogenic cysts, and to investigate the nature of these structures. All records from the patients diagnosed with inflammatory odontogenic cysts between January 1970 and April 2009 were reviewed. Histologic sections were evaluated by light microscopy and cases with HRGs for which sufficient biological material was available were submitted to histochemical analysis (Masson's trichrome) and immunohistochemistry (CD34, CD68 and collagen IV). Twenty-two (3.3%) of the 661 cases of inflammatory odontogenic cysts diagnosed during the study period presented HRGs. The relative frequency of HRGs was higher amongst residual radicular cysts (6.1%), followed by paradental cysts (5.6%) and radicular cysts (3.0%). HRGs appeared as roughly circular homogeneous/fibrillar masses in 14 (63.6%) cases and as round structures enclosing amorphous material in 3 (13.6%) cases. Most (77.8%) roughly circular homogeneous/fibrillar masses were positive for collagen, whereas all (100.0%) round structures enclosing amorphous material were negative for this protein. Immunohistochemistry showed that most mononucleated cells and all multinucleated giant cells were positive for CD68, but negative for CD34, in all cases. In addition, collagen IV immunostaining was negative in amorphous structures and weakly positive in homogeneous/fibrillar masses. The present results suggest a very low frequency of HRGs in inflammatory odontogenic cysts and support the hypothesis that these structures arise from the implantation of foreign material, most likely food particles of plant or vegetable origin. The diverse microscopic features of HRG possibly represent different developmental stages of this structure. © 2012 International Endodontic Journal.

Encystment of Azotobacter nigricans grown diazotrophically on kerosene as sole carbon source.

PubMed

García-Esquivel, Gabriela; Calva-Calva, Graciano; Ferrera-Cerrato, Ronald; Fernández-Linares, Luis Carlos; Vázquez, Refugio Rodríguez; Esparza-García, Fernando José

2009-03-01

Encystment of Azotobacter nigricans was induced by its diazotrophic cultivation on kerosene. Its growth and nitrogenase activity were affected by kerosene in comparison to cultures grown on sucrose. Electron microscopy of vegetative cells showed that when nitrogenase activity was higher and the poly-beta-hydroxybutyrate granules were not present to a significant extent, peripheral bodies were abundant. After 8 days of culture on kerosene, the presence of cysts with intracellular bunches of poly-beta-hydroxybutyrate granules was observed. Germination of cysts bears germinating multicelled yet unbroken capsule cysts with up to three cells inside. This is the first report of encystment induction of Azotobacter species grown on kerosene.

The structural bases of long-term anabiosis in non-spore-forming bacteria

NASA Astrophysics Data System (ADS)

Suzina, N. E.; Mulyukin, A. L.; Dmitriev, V. V.; Nikolaev, Yu. A.; Plakunov, V. K.; El-Registan, G. I.; Duda, V. I.

Peculiarities of the structural and functional organization related to extended and long-term anabiosis were revealed for non-spore-forming bacteria both in stored laboratory cultures and natural substrates: (1) 1-3-Myr-old Eastern Siberian permafrost, (2) tundra soils, and (3) oil slurry. Different advanced or specially designed methods were used such as (a) high-resolution electron microscopy; (b) simulation of in situ conditions in laboratory by varying of growth composition media and cultivation conditions; (c) low-temperature fractionation to isolate and concentrate microbial cells from natural substrates; (d) specimen selection and preparation; (e) comparative ultrastructural and morphometric analysis of microbial cells in model cultures and natural substrates (in situ). Under laboratory conditions, the intense formation of anabiotic (resting) cells by representatives of various taxa of eubacteria and halophilic archaea were observed in 2-9-month-old cultures grown in carbon-, nitrogen-, or phosphorus-deficient media, in starved cell suspensions in the presence of sodium silicate at environmentally occurring concentrations, or on soil agar. Among resting cells were revealed cyst-like forms possessing the complicated structure. The most common peculiarities of cyst-like resting cells were thick and distinguishable capsule; thickened and multilamellar cell wall with 1 to 3 de novo synthesized murein layers; large intramembrane particles on PF- and EF-fractures; finely granulated or coarse textured cytoplasm; condensed nucleoid. The data of morphological and ultrastructural analyses of cyst-like cells, as well as their experimentally proved resistance to prolonged desiccation, heat shock, etc. and the ability to germinate under the effect of lysozyme, gives an evidence for constitutive dormancy in the studied non-spore-forming bacteria at least. Noteworthy, it was found that the majority of microorganisms in permafrost, tundra soils, and oil slurry was presented by cyst-like cells, very similar to those in laboratory cultures and encrusted with organomineral particles. Anabiotic (resting) cyst-like cells are responsible for survival of non-spore-formers in extreme Earth habitats and may be regarded as possible analogs of extraterrestrial forms of microbial life.

Nanoceramics on osteoblast proliferation and differentiation in bone tissue engineering.

PubMed

Sethu, Sai Nievethitha; Namashivayam, Subhapradha; Devendran, Saravanan; Nagarajan, Selvamurugan; Tsai, Wei-Bor; Narashiman, Srinivasan; Ramachandran, Murugesan; Ambigapathi, Moorthi

2017-05-01

Bone, a highly dynamic connective tissue, consist of a bioorganic phase comprising osteogenic cells and proteins which lies over an inorganic phase predominantly made of CaPO 4 (biological apatite). Injury to bone can be due to mechanical, metabolic or inflammatory agents also owing pathological conditions like fractures, osteomyelitis, osteolysis or cysts may arise in enameloid, chondroid, cementum, or chondroid bone which forms the intermediate tissues of the body. Bone tissue engineering (BTE) applies bioactive scaffolds, host cells and osteogenic signals for restoring damaged or diseased tissues. Various bioceramics used in BTE can be bioactive (like glass ceramics and hydroxyapatite bioactive glass), bioresorbable (like tricalcium phosphates) or bioinert (like zirconia and alumina). Limiting the size of these materials to nano-scale has resulted in a higher surface area to volume ratio thereby improving multi-functionality, solubility, surface catalytic activity, high heat and electrical conductivity. Nanoceramics have been found to induce osteoconduction, osteointegration, osteogenesis and osteoinduction. The present review aims at summarizing the interactions of nanoceramics and osteoblast/stem cells for promoting the proliferation and differentiation of the osteoblast cells by nanoceramics as superior bone substitutes in bone tissue engineering applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of Antimicrobial Compounds on Balamuthia mandrillaris Encystment and Human Brain Microvascular Endothelial Cell Cytopathogenicity▿

PubMed Central

Siddiqui, Ruqaiyyah; Matin, Abdul; Warhurst, David; Stins, Monique; Khan, Naveed Ahmed

2007-01-01

Cycloheximide, ketoconazole, or preexposure of organisms to cytochalasin D prevented Balamuthia mandrillaris-associated cytopathogenicity in human brain microvascular endothelial cells, which constitute the blood-brain barrier. In an assay for inhibition of cyst production, these three agents prevented the production of cysts, suggesting that the biosynthesis of proteins and ergosterol and the polymerization of actin are important in cytopathogenicity and encystment. PMID:17875991

[Evaluation of signal noise ratio on analysis of clear cell renal cell carcinoma using DWI with multi-b values].

PubMed

Ding, Jiule; Xing, Wei; Chen, Jie; Dai, Yongming; Sun, Jun; Li, Dengfa

2014-01-21

To explore the influence of signal noise ratio (SNR) on analysis of clear cell renal cell carcinoma (CCRCC) using DWI with multi-b values. The images of 17 cases with CCRCC were analyzed, including 17 masses and 9 pure cysts. The signal intensity of the cysts and masses was measured separately on DWI for each b value. The minimal SNR, as the threshold, was recorded when the signal curve manifest as the single exponential line. The SNR of the CCRCC was calculated on DWI for each b value, and compared with the threshold by independent Two-sample t Test. The signal decreased on DWI with increased b factors for both pure cysts and CCRCC. The threshold is 1.29 ± 0.17, and the signal intensity of the cysts on DWI with multi-b values shown as a single exponential line when b ≤ 800 s/mm(2). For the CCRCC, the SNR is similar to the threshold when b = 1 000 s/mm(2) (t = 0.40, P = 0.69), and is lower when b = 1 200 s/mm(2) (t = -2.38, P = 0.03). The SNR should be sufficient for quantitative analysis of DWI, and the maximal b value is 1000 s/mm(2) for CCRCC.

The Structure of Resting Bacterial Populations in Soil and Subsoil Permafrost

NASA Astrophysics Data System (ADS)

Soina, Vera S.; Mulyukin, Andrei L.; Demkina, Elena V.; Vorobyova, Elena A.; El-Registan, Galina I.

2004-09-01

The structure of individual cells in microbial populations in situ of the Arctic and Antarctic permafrost was studied by scanning and transmission electron microscopy methods and compared with that of cyst-like resting forms generated under special conditions by the non-sporeforming bacteria Arthrobacter and Micrococcus isolated from the permafrost. Electron microscopy examination of microorganisms in situ revealed several types of bacterial cells having no signs of damage, including "dwarf" curved forms similar to nanoforms. Intact bacterial cells in situ and frozen cultures of the permafrost isolates differed from vegetative cells by thickened cell walls, the altered structure of cytoplasm, and the compact nucleoid, and were similar in these features to cyst-like resting forms of non-spore-forming "permafrost" bacterial strains of Arthrobacter and Micrococcus spp. Cyst-like cells, being resistant to adverse external factors, are regarded as being responsible for survival of the non-spore-formers under prolonged exposure to subzero temperatures and can be a target to search for living microorganisms in natural environments both on the Earth and on extraterrestrial bodies.

Establishment of a C57BL/6N mouse model of giardiasis.

PubMed

Lu, Siqi; Luo, Xiaobing; Chen, Xiaoning; Wang, Fengyun

2002-10-01

To establish a C57BL/6N mouse model infected with Giardia lamblia (G. lamblia) isolates from human origin. Two groups of C57BL/6N mouse were inoculated with purified cysts of two G. lamblia isolates (CD and XZ) by gavage separately. Patterns and curves of cyst excretion of the infected mice were observed and summarized. Histopathological changes of the small intestines of the infected mice were observed. Thirty-six mice receiving 1 x 10(4) cysts each were all infected. The C57BL/6N mouse showed high susceptibility to G. lamblia infection. There was no notable distinction between the two groups of the mice infected by the cysts of CD and XZ isolates. Cyst excretion occurred with intermittence. Of 36 infected mice, 32 (89%) passed cysts intermittently and 4 (11%) others persistently. The latent period of cyst excretion was 0 - 3 days p.i. (post-inoculation). The interruption of cyst excretion ranged from 12 to 20 days p.i. The fastigium of the cyst excretion was on day 6 p.i. The peak count of the cysts passed during a 2 h collection period was 2.3 x 10(7)/g fecal specimen. Edema, inflammation, cell infiltration, small blood vessels congestion, mitotic figures and mucosa necrosis appeared in sections of intestines. C57Bl/6N mouse is a suitable animal model of G. lamblia.

Malignant Change in an Epidermal Cyst Over Gluteal Region

PubMed Central

Kshirsagar, Ashok Y; Sulhyan, Sanjitsingh R; Deshpande, Shradha; Jagtap, SV

2011-01-01

A 72-year-old male presented with a large ulceroproliferative lesion over left gluteal region. After histopathological confirmation of squamous cell carcinoma, the lesion was excised with wide margins. Further histopathological study of the excised specimen revealed the growth arising from an epidermal cyst. Malignant change is a rare, but wellknown complication occurring in an epidermal cyst. The mainstay of treatment consists of wide excision of cancerous lesion with primary reconstruction of the defect. PMID:21572684

Temporal remodeling of the cell cycle accompanies differentiation in the Drosophila germline.

PubMed

Hinnant, Taylor D; Alvarez, Arturo A; Ables, Elizabeth T

2017-09-01

Development of multicellular organisms relies upon the coordinated regulation of cellular differentiation and proliferation. Growing evidence suggests that some molecular regulatory pathways associated with the cell cycle machinery also dictate cell fate; however, it remains largely unclear how the cell cycle is remodeled in concert with cell differentiation. During Drosophila oogenesis, mature oocytes are created through a series of precisely controlled division and differentiation steps, originating from a single tissue-specific stem cell. Further, germline stem cells (GSCs) and their differentiating progeny remain in a predominantly linear arrangement as oogenesis proceeds. The ability to visualize the stepwise events of differentiation within the context of a single tissue make the Drosophila ovary an exceptional model for study of cell cycle remodeling. To describe how the cell cycle is remodeled in germ cells as they differentiate in situ, we used the Drosophila Fluorescence Ubiquitin-based Cell Cycle Indicator (Fly-FUCCI) system, in which degradable versions of GFP::E2f1 and RFP::CycB fluorescently label cells in each phase of the cell cycle. We found that the lengths of the G1, S, and G2 phases of the cell cycle change dramatically over the course of differentiation, and identified the 4/8-cell cyst as a key developmental transition state in which cells prepare for specialized cell cycles. Our data suggest that the transcriptional activator E2f1, which controls the transition from G1 to S phase, is a key regulator of mitotic divisions in the early germline. Our data support the model that E2f1 is necessary for proper GSC proliferation, self-renewal, and daughter cell development. In contrast, while E2f1 degradation by the Cullin 4 (Cul4)-containing ubiquitin E3 ligase (CRL4) is essential for developmental transitions in the early germline, our data do not support a role for E2f1 degradation as a mechanism to limit GSC proliferation or self-renewal. Taken together, these findings provide further insight into the regulation of cell proliferation and the acquisition of differentiated cell fate, with broad implications across developing tissues. Copyright © 2017 Elsevier Inc. All rights reserved.

Extracellular accumulations in the avian pituitary gland: histochemical analysis in two species of Indian wild birds.

PubMed

Mohanty, Banalata

2006-01-01

Extracellular accumulations of two distinct types, colloid-filled follicles and fibrous-material-containing cysts, were observed in the pituitary gland of two species of Indian wild birds, Halcyon smyrnensis perpulchra and Lonchura striata striata. Colloid follicles were regular structures and distributed throughout the pars distalis (PD). The fibrous cysts were irregular structures, bigger than the colloid follicles and mostly observed towards the ventral margin of the PD. Sometimes disruption of the outer margin with depletion of fibrous material from the cavity was observed. Hormone-secreting cells of various types, anti-adrenocorticotropic-hormone-, anti-prolactin-, anti-growth-hormone- and anti-luteinizing-hormone-immunoreactive cells were encountered bordering both the colloid follicles and fibrous cysts. Neither the colloid nor the fibrous material showed any immunoreaction to any of the pituitary hormone antisera. On histochemical staining colloid was positive to periodic acid-Schiff (PAS) and fibrous materials stained with Alcian blue-PAS-orange G staining. Colloid depositions in the pituitary gland of these two wild birds were correlated to age, more in numbers in the adult birds than in the young ones. Fibrous-material-containing cysts were elucidated in the pituitary gland of adult birds only. These were more prevalent in the pituitary of reproductively active birds. Regular morphology of the colloid follicles, overall distribution in the adenohypophysis and dense nature of deposition of the colloid suggest the accumulation of this type may be the secretory products of both granulated and agranulated pituitary cell types. Absence of immunoreactivity of the colloid against pituitary hormone antisera points out that the storage form may differ chemically from the bioactive hormones. The spatial distribution of fibrous-material-containing cysts mostly towards the ventral PD, observations of immunoreactive cell fragmentations inside the cysts, and their disrupted margins suggest these structures may have some role in discharging the intraglandular degradation products. 2006 S. Karger AG, Basel

Cross-species transmission of Giardia spp.: inoculation of beavers and muskrats with cysts of human, beaver, mouse, and muskrat origin.

PubMed Central

Erlandsen, S L; Sherlock, L A; Januschka, M; Schupp, D G; Schaefer, F W; Jakubowski, W; Bemrick, W J

1988-01-01

Giardia cysts isolated from humans, beavers, mice, and muskrats were tested in cross-species transmission experiments for their ability to infect either beavers or muskrats. Giardia cysts, derived from multiple symptomatic human donors and used for inoculation of beavers or muskrats, were shown to be viable by incorporation of fluorogenic dyes, excystation, and their ability to produce infections in the Mongolian gerbil model. Inoculation of beavers with 5 x 10(5) Giardia lamblia cysts resulted in the infection of 75% of the animals (n = 8), as judged by the presence of fecal cysts or intestinal trophozoites at necropsy. The mean prepatent period was 13.1 days. An infective dose experiment, using 5 x 10(1) to 5 x 10(5) viable G. lamblia cysts collected by fluorescence-activated cell sorting, demonstrated that doses of between, less than 50, and less than 500 viable cysts were required to produce infection in beavers. Scanning electron microscopy of beaver small intestine revealed that attachment of G. lamblia trophozoites produced lesions in the microvillous border. Inoculation of muskrats with G. lamblia cysts produced infections when the dose of cysts was equal to or greater than 1.25 x 10(5). The inoculation of beavers with Giardia ondatrae or Giardia muris cysts did not produce any infection; however, the administration to muskrats of Giardia cysts of beaver origin resulted in the infection of 62% of the animals (n = 8), with a prepatent period of 5 days. Our results demonstrated that beavers and muskrats could be infected with Giardia cysts derived from humans, but only by using large numbers of cysts.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:3063208

Precocious pseudopuberty due to an autonomous ovarian follicular cyst: case report with a review of literatures

PubMed Central

2013-01-01

Background Small follicular cysts are commonly found in the ovaries of prepubertal girls, and in most cases, they are of no clinical importance. These cysts are usually self-limiting and resolve spontaneously. However, occasionally, these cysts may enlarge and continue to produce estrogen, resulting in signs of sexual precocity. Here, we report a case of precocious pseudopuberty associated with an autonomous ovarian follicular cyst. Case presentation A 5.9-year-old girl initially presented to a local clinic with vaginal bleeding and a large unilateral ovarian cyst. At 6 months after the initial acute episode, the patient visited our hospital as the ovarian cyst had persisted and increased in size. Endocrinological examination showed elevated estrogen levels and suppressed gonadotropin levels on GnRH stimulation test. Also, no skin pigmentation or bone anomaly was noted. Based on these observations, laparoscopic cystectomy was performed, and histologic analysis confirmed the diagnosis of a follicular cyst. After the laparoscopic cystectomy, the patient’s hormone levels returned to normal and no ovarian cyst was detected by ultrasound. Conclusions As autonomous ovarian cysts are usually self-limiting disorder, no treatment is necessary. Therefore, surgical management should be deferred as long as possible to avoid the risk of repeat surgery, as pseudoprecocious puberty due to autonomous ovarian cysts can resolve spontaneoulsy and frequently recurs. Precocious pseudopuberty with an ovarian cyst may be due to granulosa cell tumor or may be one symptom of the McCune-Albright Syndrome (MAS). A careful longer-term follow up of patients with autonomous ovarian cysts and/or molecular studies may be necessary in such cases. PMID:23937919

The Trophic Life Cycle Stage of the Opportunistic Fungal Pathogen Pneumocystis murina Hinders the Ability of Dendritic Cells To Stimulate CD4+ T Cell Responses

PubMed Central

Evans, Heather M.; Simpson, Andrew; Shen, Shu; Stromberg, Arnold J.; Pickett, Carol L.

2017-01-01

ABSTRACT The life cycle of the opportunistic fungal pathogen Pneumocystis murina consists of a trophic stage and an ascus-like cystic stage. Infection with the cyst stage induces proinflammatory immune responses, while trophic forms suppress the cytokine response to multiple pathogen-associated molecular patterns (PAMPs), including β-glucan. A targeted gene expression assay was used to evaluate the dendritic cell response following stimulation with trophic forms alone, with a normal mixture of trophic forms and cysts, or with β-glucan. We demonstrate that stimulation with trophic forms downregulated the expression of multiple genes normally associated with the response to infection, including genes encoding transcription factors. Trophic forms also suppressed the expression of genes related to antigen processing and presentation, including the gene encoding the major histocompatibility complex (MHC) class II transactivator, CIITA. Stimulation of dendritic cells with trophic forms, but not a mixture of trophic forms and cysts, reduced the expression of MHC class II and the costimulatory molecule CD40 on the surface of the cells. These defects in the expression of MHC class II and costimulatory molecules corresponded with a reduced capacity for trophic form-loaded dendritic cells to stimulate CD4+ T cell proliferation and polarization. These data are consistent with the delayed innate and adaptive responses previously observed in immunocompetent mice inoculated with trophic forms compared to responses in mice inoculated with a mixture of trophic forms and cysts. We propose that trophic forms broadly inhibit the ability of dendritic cells to fulfill their role as antigen-presenting cells. PMID:28694293

Expression of interleukin-33 and its receptor ST2 in periapical granulomas and radicular cysts.

PubMed

Velickovic, Milena; Pejnovic, Nada; Petrovic, Renata; Mitrovic, Slobodanka; Jeftic, Ilija; Kanjevac, Tatjana; Lukic, Aleksandra

2016-01-01

Interleukin-33 (IL-33) is a recently identified cytokine belonging to the IL-1 family and ligand for the IL-1 receptor-related protein ST2. IL-33/ST2 signaling plays a critical role in allergy, autoimmunity, and chronic inflammatory disorders, but its role in the pathogenesis of periapical lesions is unknown. We aimed to investigate the expression patterns of IL-33 and ST2 in human periapical lesions. Periapical lesions (n = 36) and healthy periapical tissues (n = 10) were evaluated by immunohistochemistry using antibodies specific for human IL-33 and ST2. Lesion samples were further analyzed by double immunofluorescence to assess IL-33/ST2 co-expression. The numbers of IL-33- and ST2-positive fibroblasts were significantly higher in periapical lesions compared to healthy periapical tissues (both P < 0.05), while the numbers of IL-33- and ST2-positive endothelial cells were similar (both P > 0.05). There were no significant differences in the numbers of IL-33- and ST2-positive fibroblasts and endothelial cells between periapical granulomas and radicular cysts (all P > 0.05). Similarly, numbers of ST2-positive mononuclear cells did not differ between periapical granulomas and radicular cysts (P > 0.05). The majority of epithelial cells in radicular cysts were IL-33 positive, while the small proportion of epithelial cells was ST2 positive. Double immunofluorescence analysis revealed IL-33/ST2 co-expression in fibroblasts and endothelial cells. IL-33 and ST2 are expressed in periapical granulomas and radicular cysts. Increased numbers of IL-33- and ST2-positive fibroblasts in periapical lesions when compared to healthy periapical tissues suggest that IL-33/ST2 signaling may be involved in periapical inflammation and tissue fibrosis. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Primary intraosseous squamous cell carcinoma in odontogenic keratocyst: A rare entity

PubMed Central

Saxena, Chitrapriya; Aggarwal, Pooja; Wadhwan, Vijay; Bansal, Vishal

2015-01-01

Squamous cell carcinoma (SCC) arising from the wall of an odontogenic cyst (also known as primary intraosseous carcinoma) is a rare tumor which occurs only in jaw bones. This tumor was first described by Loos in 1913 as a central epidermoid carcinoma of the jaw. Primary intraosseous carcinomas (PIOC) may theoretically arise from the lining of an odontogenic cyst or de novo from presumed odontogenic cell rests. According to the new histological classification of tumors of the World Health Organization, odontogenic keratocyst is nowadays considered a specific odontogenic tumor and the PIOC derived from it is considered as a specific entity which is different from other PIOCs derived from the odontogenic cysts. The following report describes a case of such extremely rare entity that is primary intraosseous SCC of the mandible derived from an OKC in a 60-year-old male patient with brief review of literature. PMID:26980976

Multicystic dedifferentiated retroperitoneal liposarcoma: tumour cyst fluid analysis and implications for management

PubMed Central

Khoury, Mitri; Sim, Geok Choo; Harao, Michiko; Radvanyi, Laszlo; Amini, Behrang; Benjamin, Robert S; Pisters, Peter W T; Pollock, Raphael E; Tseng, William W

2015-01-01

Liposarcomas are soft tissue sarcomas of adipocyte origin. We describe a case of a dedifferentiated retroperitoneal liposarcoma with an unusual presentation on recurrence as a large, multicystic tumour. The patient was a 72-year-old woman who had undergone multiple treatments including two prior resections. For her most recent locoregional disease recurrence, the patient was offered surgical debulking for symptom palliation. At this operation, performed after two cycles of chemotherapy, the tumour cyst fluid was analysed and found to have a predominance of immune cells with no identifiable malignant cells. This case and the results of our tumour cyst fluid analysis raise several interesting considerations for the management of this unique situation in a rare disease. PMID:26156843

Multicystic dedifferentiated retroperitoneal liposarcoma: tumour cyst fluid analysis and implications for management.

PubMed

Khoury, Mitri; Sim, Geok Choo; Harao, Michiko; Radvanyi, Laszlo; Amini, Behrang; Benjamin, Robert S; Pisters, Peter W T; Pollock, Raphael E; Tseng, William W

2015-07-08

Liposarcomas are soft tissue sarcomas of adipocyte origin. We describe a case of a dedifferentiated retroperitoneal liposarcoma with an unusual presentation on recurrence as a large, multicystic tumour. The patient was a 72-year-old woman who had undergone multiple treatments including two prior resections. For her most recent locoregional disease recurrence, the patient was offered surgical debulking for symptom palliation. At this operation, performed after two cycles of chemotherapy, the tumour cyst fluid was analysed and found to have a predominance of immune cells with no identifiable malignant cells. This case and the results of our tumour cyst fluid analysis raise several interesting considerations for the management of this unique situation in a rare disease. 2015 BMJ Publishing Group Ltd.

Periorbital cyst with bone defect in a dog.

PubMed

Ito, Kanako; Asano, Kazushi; Urano, Toshiaki; Ogiwara, Naoki; Seki, Mamiko; Kato, Yuka; Sasaki, Yukie; Teshima, Kenji; Kutara, Kenji; Edamura, Kazuya; Shibuya, Hisashi; Tanaka, Shigeo

2006-07-01

A 4-year-old female Miniature Dachshund was referred with a chief complaint of right periorbital swelling that had not responded to antibiotic therapy. Ultrasonography and fine-needle aspiration revealed that the periorbital lesion had a cystic structure without any inflammatory or neoplastic cells. Computed tomography (CT) showed that the cyst occupied a defect in the periorbital maxillary, lacrimal, and frontal bones and had invaded the nasal cavity. The lesion was histologically suspected by incisional biopsy as an epithelial cyst.

Proterozoic microfossils revealing the time of algal divergences

NASA Astrophysics Data System (ADS)

Moczydlowska-Vidal, Malgorzata

2010-05-01

Proterozoic microfossils revealing the time of algal divergences Małgorzata Moczydłowska-Vidal Uppsala University, Department of Earth Sciences, Palaeobiology, Villavägen 16, SE 752 36 Uppsala, Sweden (malgo.vidal@pal.uu.se) Morphological and reproductive features and cell wall ultrastructure and biochemistry of Proterozoic acritarchs are used to determine their affinity to modern algae. The first appearance datum of these microbiota is traced to infer a minimum age of the divergence of the algal classes to which they may belong. The chronological appearance of microfossils that represent phycoma-like and zygotic cysts and vegetative cells and/or aplanospores, respectively interpreted as prasinophyceaen and chlorophyceaen microalgae, is related to the Viridiplantae phylogeny. These divergence times differ from molecular clock estimates, and the palaeontological evidence suggests that they are older. The best examples of unicellular, organic-walled microfossils (acritarchs) from the Mesoproterozoic to Early Ordovician are reviewed to demonstrate features, which are indicative of their affinity to photosynthetic microalgae. The first indication that a microfossil may be algal is a decay- and acid-resistant cell wall, which reflects its biochemistry and ultrastructure, and probably indicates the ability to protect a resting/reproductive cyst. The biopolymers synthesized in the cell walls of algae and in land plants ("plant cells"), such as sporopollenin/algaenan, are diagnostic for photosynthetic taxa and were inherited from early unicellular ancestors. These preservable cell walls are resistant to acetolysis, hydrolysis and acids, and show diagnostic ultrastructures such as the trilaminar sheath structure (TLS). "Plant cell" walls differ in terms of chemical compounds, which give high preservation potential, from fungal and animal cell walls. Fungal and animal cells are fossilized only by syngenetic permineralization, whereas "plant cells" are fossilized as body fossils more ubiquitously and without mineralization. Microalgae radiated quickly in the Cambrian and Ordovician; however, several morphotypes with features related to the reproductive cycle occur in the Proterozoic, although they are not always recognized as such. The assignment of Proterozoic unicellular microfossils with resistant cell walls to specific eukaryotic groups is tentative. However, we argue that the new interpretations of their functional morphology, combined with cell wall ultrastructure and biochemistry, allow their assignment to microalgal classes. Microfossils with advanced ornamentation and ontogenetically formed excystment structures or endocysts, which prove that they are cysts in a complex life cycle with sexual reproduction, are related to the basal lineage of the Chlorophytes and the class Chlorophyceae. A cell wall ultrastructure with a TLS supports the affinity of some spheroidal taxa to the Chlorophytes. The phylogeny of the Chlorophytes shows a sequence of branching nodes from a stem-group of the Viridiplantae that leads to the classes Prasinophyceae and Chlorophyceae, and then the Ulvophyceae. Based on a modern interpretation of the record, the timing of these nodes is deduced to be prior to c. 1650 Ma for the Prasinophyceae, c. 1450 Ma for the Chlorophyceae, and c. 950 Ma for the Ulvophyceae. The origin of the Chlorophytes, and in general the Viridiplantae, predates 1.8 Ga. These ages, based on microfossils, are earlier than the estimates based on molecular clocks.

Trichinosis in Maryland raccoons

USGS Publications Warehouse

Winslow, D.J.; Price, D.L.; Neafie, R.C.; Herman, C.M.

1966-01-01

During recent studies of experimental Chagas’ disease, trichinosis was found in 2 out of a total of 44 Maryland raccoons (Procyon lotor) examined histologically following necropsy. All raccoons were trapped near the towns of Beltsville or Laurel. The raccoons found to have trichinosis were trapped in the area of the Agricultural Research Center, Beltsville. Cysts containing larvae of Trichinella spiralis were found in sections of diaphragm in one raccoon and in sections of diaphragm, skeletal muscle, and ocular muscle in the other. Three to five cysts could he seen in sections of skeletal muscle or diaphragm within a single low-power (scanning lens X 40) field. There was little if any inflammatory reaction to most of these cysts, but inflammatory cells were present adjacent to an occasional cyst (Fig. 1). Foci of calcification were found in some sections of muscle and may represent old calcified cysts.

Morphometric evaluation of AgNORs in odontogenic cysts.

PubMed

Sreeshyla, Huchanahalli S; Shashidara, Raju; Sudheendra, Udyavara Sridhara

2013-10-01

To evaluate the morphometry of AgNORs in odontogenic cysts and to compare their biologic behavior to determine whether AgNOR morphometry is helpful in predicting the behavior. Ten cases each of odontogenic keratocyst (OKC), dentigerous cyst (DC) and radicular cyst (RC) were stained with silver nitrate. Morphometric analysis of 100 selected epithelial and connective tissue cells was done to record their nuclear volume, nuclear perimeter, contour index of the nucleus, AgNOR count, AgNOR proportion and single AgNOR volume. The results were statistically analyzed using ANOVA. AgNOR count, nuclear volume and nuclear perimeter were greatest in the OKC followed by DC and RC, suggesting that these parameters differentiate between the aggressive and less aggressive odontogenic cysts. Single AgNOR volume and AgNOR proportion were greatest in the RC followed by OKC and DC, respectively. Results of our study taken in isolation point to AgNOR count as the most reliable factor in differentiating between aggressive and nonaggressive odontogenic cysts.

Colloid cyst of the third ventricle, hypothalamus, and heart: a dangerous link for sudden death

PubMed Central

2012-01-01

Abstract Colloid cysts are rare congenital, intracranial neoplasms, commonly located in the third ventricle. Colloid cysts are endodermal congenital malformations. The cysts commonly range in size from 1–2 cm in diameter, although large cysts >3 cm in size have been reported. The components of the cyst include an outer fibrous capsule over an inner epithelium. The epithelium is usually a single layer of mucin-producing or ciliated cells. Such cysts contain mucoid and gelatinous material, which is positive for both Periodic acid Schiff (PAS) and mucicarmen staining. Although colloid cysts usually represent histopathologically benign neoplasms, they can result in sudden, unexpected and potentially lethal complications. The mechanism(s) of death is still a controversial subject and several mechanisms have been postulated to explain the sudden onset of severe symptoms and of fatal rapid deterioration in patients with colloid cysts. In this case, macroscopic and histological findings addressed the diagnosis of colloid cyst of the third ventricle with diffuse myocardial injury (coagulative myocytolysis or contraction band necrosis, CBN) and led us to conclude that acute cardiac arrest due to hypothalamus stimulation in the context of colloid cyst of the third ventricle was the cause of death. As the hypothalamic structures which are involved in neuroendocrine and autonomic regulation playing a key role in cardiovascular control are located close to the walls of the third ventricle which is the most frequent anatomical site of colloid cyst, this may suggest that reflex cardiac effects due to the compression of the hypothalamic cardiovascular regulatory centers by the cyst explain the sudden death in patients harboring a colloid cyst when signs of hydrocephalus or brain herniation are lacking. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4915842848034158 PMID:23078815

Protein Phosphatase 1ß Limits Ring Canal Constriction during Drosophila Germline Cyst Formation

PubMed Central

Yamamoto, Shinya; Bayat, Vafa; Bellen, Hugo J.; Tan, Change

2013-01-01

Germline cyst formation is essential for the propagation of many organisms including humans and flies. The cytoplasm of germline cyst cells communicate with each other directly via large intercellular bridges called ring canals. Ring canals are often derived from arrested contractile rings during incomplete cytokinesis. However how ring canal formation, maintenance and growth are regulated remains unclear. To better understand this process, we carried out an unbiased genetic screen in Drosophila melanogaster germ cells and identified multiple alleles of flapwing (flw), a conserved serine/threonine-specific protein phosphatase. Flw had previously been reported to be unnecessary for early D. melanogaster oogenesis using a hypomorphic allele. We found that loss of Flw leads to over-constricted nascent ring canals and subsequently tiny mature ring canals, through which cytoplasmic transfer from nurse cells to the oocyte is impaired, resulting in small, non-functional eggs. Flw is expressed in germ cells undergoing incomplete cytokinesis, completely colocalized with the Drosophila myosin binding subunit of myosin phosphatase (DMYPT). This colocalization, together with genetic interaction studies, suggests that Flw functions together with DMYPT to negatively regulate myosin activity during ring canal formation. The identification of two subunits of the tripartite myosin phosphatase as the first two main players required for ring canal constriction indicates that tight regulation of myosin activity is essential for germline cyst formation and reproduction in D. melanogaster and probably other species as well. PMID:23936219

Diagnostic dilemma of unicystic ameloblastoma: novel parameters to differentiate unicystic ameloblastoma from common odontogenic cysts.

PubMed

Gunawardhana, Kuda Singappulige Niluka Darshani; Jayasooriya, Primali Rukmal; Tilakaratne, Wanninayake Mudiyanselage

2014-08-01

Diagnostic criteria that have been specified for unicystic ameloblastomas (UAs) are not always helpful to differentiate these cystic tumors from common odontogenic cysts. The aim of this study therefore was to identify additional histopathological features (other than the features considered for the diagnosis of UA at present) that would be helpful to differentiate UA from odontogenic cysts. One hundred histopathologically confirmed unicystic ameloblastomas and 20 cases each of radicular, inflamed dentigerous and non-inflamed dentigerous cysts were selected. Histopathological features of the UAs that are not used as diagnostic criteria at present were identified. Hyperplastic arcading epithelial proliferations with stellate-reticulum-like and vacuolated cells were always seen associated with inflammation in odontogenic cysts, while in UA plexiform-like areas were also seen without inflammation (P < 0.001). In addition, a spiky rete pattern was observed in non-inflamed UA while this pattern was observed only in inflamed odontogenic cysts. Furthermore, spiky retes together with subepithelial hyalinization were usually observed in UAs while only subepithelial hyalinization was observed in non-inflamed dentigerous cysts. Combinations of histopathological features were identified to differentiate non-inflamed UA from common odontogenic cysts. However, presence of inflammatory changes in UA precludes the use of features identified in the present study for diagnostic purposes. © 2013 Wiley Publishing Asia Pty Ltd.

Characterization of susceptibility and resistance responses to potato cyst nematode (Globodera spp.) infection of tomato lines in the absence and presence of the broad-spectrum nematode resistance Hero gene.

PubMed

Sobczak, Miroslaw; Avrova, Anna; Jupowicz, Justyna; Phillips, Mark S; Ernst, Karin; Kumar, Amar

2005-02-01

The tomato Hero A gene is the only member of a multigene family that confers a high level (>80%) of resistance to all the economically important pathotypes of potato cyst nematode (PCN) species Globodera rostochiensis and G. pallida. Although the resistance levels of transgenic tomato lines were similar to those of the tomato line LA1792 containing the introgressed Hero multigene family, transgenic potato plants expressing the tomato Hero A gene are not resistant to PCNs. Comparative microscopy studies of in vitro infected roots of PCN-susceptible tomato cv. Money Maker, the resistant breeding line LA1792, and transgenic line L10 with Ro1 pathotype have revealed no statistically significant difference in the number of juveniles invading roots. However, syncytia (specialized feeding cells) induced in LA1792 and L10 roots mostly were found to have degenerated a few days after their induction, and a few surviving syncytia were able to support only the development of males rather than females. Thus, the ratio between males and females was biased towards males on LA1792 and L10 roots. A series of changes occur in resistant plants leading to formation of a layer of necrotic cells separating the syncytium from stellar conductive tissues and this is followed by degradation of the syncytium. Although the Hero A gene is expressed in all tissues, including roots, stems, leaves, and flower buds, its expression is upregulated in roots in response to PCN infection. Moreover, the expression profiles of the Hero A correlates with the timing of death of the syncytium.

Cellular targeting and host-specific recognition of cyst nematode CLE proteins

USDA-ARS?s Scientific Manuscript database

Cyst nematodes produce secreted peptide mimics of plant CLAVATA3/ESR (CLE) peptides likely involved in redirecting CLE signaling pathways active in roots to form unique and essential feeding cells. The hallmark structure of plant CLEs, which includes an N-terminal signal peptide, a highly variable d...

Immunohistochemical expression of Notch signaling in the lining epithelium of periapical cysts.

PubMed

Meliou, Eleni; Kerezoudis, Nikolaos; Tosios, Konstantinos; Lafkas, Daniel; Kiaris, Hippokratis

2011-02-01

In this study we evaluated the immunohistochemical expression of the receptors Notch 1 and Notch 2, the ligand Delta 1, and the transcription factors HES 1 and HES 5 in the epithelium of well-defined periapical cysts. Immunohistochemistry was carried out on 55 formalin-fixed and paraffin-embedded, well-defined periapical cysts with minimum inflammation, obtained from the archival tissue database of the Department of Oral Pathology and Surgery. Western blotting was performed to evaluate the specificity of the anti-Notch antibody and the expression of Notch signaling in 5 fresh-frozen periapical cysts. The levels of staining intensity were estimated by the performance of a semiautomated image analysis system. Descriptive statistic of mean values obtained by computerized image analysis method was performed. Immunostaining reaction of all Notch signaling components was observed in the cytoplasm and/or the cytoplasmic membrane in the majority of epithelial cells of periapical cysts. Nuclear staining was observed occasionally in all cases. Notch 2 showed strong staining in 52.83% of the cases, followed by Notch 1 (35.85%), HES 1 and HES 5 moderate staining in 72.73% and 57.69% of the cases, respectively, and Delta 1 weak staining in 58.33% of the cases. No statistical correlation was found between the antibodies and the sex or the age of the study group. Notch is an evolutionarily conserved signaling mechanism that regulates cell fate decisions during development and postnatal life in organisms as diverse as worms, flies, and humans. The present observations indicate that Notch pathway is active downstream in the lining epithelium of periapical cysts, suggesting an involvement of this pathway in periapical cyst growth and expansion. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Adhesion molecules, chemokines and matrix metallo-proteinases response after albendazole and albendazole plus steroid therapy in swine neurocysticercosis.

PubMed

Singh, Satyendra K; Prasad, Kashi N; Singh, Aloukick K; Gupta, Kamlesh K; Singh, Amrita; Tripathi, Mukesh; Gupta, Rakesh K

2017-11-01

The treatment of neurocysticercosis (NCC) varies with location, number and stage of the Taenia solium cysticerci (cysts). Albendazole (ABZ) effectively kills cysticerci, and subsequently induces neuro-inflammation facilitated by leukocyte infiltration. We hypothesize that immune response varies around drug responder (degenerating/dying) and non-responder (viable) cysts after ABZ and ABZ plus steroid (ABZS) therapy, which may determine the disease pathogenesis. Twenty cysticercotic swine were treated with ABZ (n = 10; group1) and ABZS (n = 10; group2). Expression of adhesion molecules, chemokines and matrix metallo-proteinases (MMPs) was measured by qRT-PCR (quantitative reverse transcriptase-polymerase chain reaction) and ELISA. Gelatin gel zymography was performed to detect the activity of MMP-2 and -9. In group1, ABZ therapy induced higher expressions of ICAM-1 (intercellular adhesion molecule-1), VCAM-1 (vascular cell adhesion molecule-1), E-selectin, MCP-1 (monocyte chemotactic protein-1), Eotaxin-1, MIP-1α (macrophage inflammatory protein-1α), RANTES (regulated on activation, normal T cell expressed and secreted), MMP-2 and MMP-9 around ABZ responder (AR) cysts. Three pigs with cyst burdens ≥10 died following ABZ therapy. However, in group2, moderate expressions of ICAM-1, VCAM-1, E-selectin, RANTES and MMP-9 were associated with ABZS responder (ASR), whereas low expressions of these molecules were associated with ABZS non-responder (ASNR) cysts. In conclusion, ABZ alone therapy is not safe since it causes death of pigs due to higher inflammatory immune response around dying cysts. However, combination therapy is an effective treatment regimen even with the high cyst burden. Copyright © 2017 Elsevier Inc. All rights reserved.

Inhibition of Intrahepatic Bile Duct Dilation of the Polycystic Kidney Rat with a Novel Tyrosine Kinase Inhibitor Gefitinib

PubMed Central

Sato, Yasunori; Harada, Kenichi; Furubo, Shinichi; Kizawa, Kazuo; Sanzen, Takahiro; Yasoshima, Mitsue; Ozaki, Satoru; Isse, Kumiko; Sasaki, Motoko; Nakanuma, Yasuni

2006-01-01

The polycystic kidney (PCK) rat represents a liver and kidney cyst pathology corresponding to Caroli’s disease with congenital hepatic fibrosis and autosomal recessive polycystic kidney disease. We previously reported that an epidermal growth factor receptor tyrosine kinase inhibitor, gefitinib (Iressa), significantly inhibited the abnormal growth of biliary epithelial cells of PCK rats in vitro. This study investigated the effects of gefitinib on cyst pathogenesis of the PCK rat both in vitro and in vivo. A three-dimensional culture model of biliary epithelial cells in the collagen gel matrix was used for in vitro analysis. For in vivo experiments, PCK and control rats were treated with gefitinib between 3 and 10 weeks of age. In vitro, gefitinib had strong inhibitory effects on biliary cyst formation of PCK rats. In vivo, treatment with gefitinib significantly inhibited the cystic dilatation of the intrahepatic bile ducts of PCK rats, which was accompanied by improvement of liver fibrosis. By contrast, no beneficial effects were observed on renal cyst development because of the treatment. These results suggest that signaling pathways mediated by epidermal growth factor receptor are involved in biliary dysgenesis of the PCK rat, with the mechanisms of cyst progression being different between the liver and kidney. PMID:17003482

Fine needle aspiration cytology versus frozen section in branchial cleft cysts.

PubMed

Begbie, F; Visvanathan, V; Clark, L J

2015-02-01

Branchial cleft cysts occur because of a failure of involution of the second branchial cleft. However, as well-differentiated squamous cell carcinoma can mimic branchial cleft cysts, there is a lack of consensus on the appropriate management of cystic neck lumps. To report our experience of fine needle aspiration cytology and frozen section examination in the management of cystic neck lumps. Retrospective case note review of patients managed in the Southern General Hospital, Scotland, UK. The sensitivity of fine needle aspiration cytology and frozen section for detecting branchial cleft cysts was 75 per cent and 100 per cent respectively. Two patients who did not undergo intra-operative frozen section examination were either over- or under-treated, which is discussed. Adult patients subjected to surgical excision of a suspected branchial cyst should undergo intra-operative frozen section analysis regardless of clinical suspicion for malignancy. This part of management is critical to ensure patients are offered appropriate treatment.

Polycystic Liver Disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Linda, Nguyen, E-mail: nguyenli@einstein.edu

A 77-year-old African American male presented with intermittent abdominal pain for one week. He denied nausea, vomiting, diarrhea, constipation, fevers, anorexia, or weight loss. He denied a family history of liver disease, recent travel, or history of intravenous drug abuse. His vital signs were normal. Labs revealed total bilirubin of 1.5 mg/dl, hypoalbuminaemia 3.0 gm/dl and prolonged prothrombin time of 14.8 sec. Computed Tomography of the abdomen and pelvis with contrast showed multiple hepatic cysts with the largest cyst occupying the right abdomen, measuring 20.6 cm (Panel A and). This cyst had predominantly fluid attenuation, but also contained several septations.more » The patient underwent laparoscopic fenestration of the large hepatic cyst with hepatic cyst wall biopsy. Pathology revealed blood without malignant cells. The patient tolerated the procedure well with improvement of his abdominal pain and normalization of his liver function tests and coagulation profile.« less

[Giant paraovarian cyst in childhood - Case report].

PubMed

Torres, Janina P; Íñiguez, Rodrigo D

2015-01-01

Paraovarian cysts are very uncommon in children To present a case of giant paraovarian cyst case in a child and its management using a modified laparoscopic-assisted technique A 13-year-old patient with a 15 day-history of intermittent abdominal pain, located in the left hemiabdomen and associated with progressive increase in abdominal volume. Diagnostic imaging was inconclusive, describing a giant cystic formation that filled up the abdomen, but without specifying its origin. Laboratory tests and tumor markers were within normal range. Video-assisted transumbilical cystectomy, a modified laparoscopic procedure with diagnostic and therapeutic intent, was performed with a successful outcome. The histological study reported giant paraovarian cyst. Cytology results were negative for tumor cells. The patient remained asymptomatic during the postoperative follow-up. The video-assisted transumbilical cystectomy is a safe procedure and an excellent diagnostic and therapeutic alternative for the treatment of giant paraovarian cysts. Copyright © 2015. Publicado por Elsevier España, S.L.U.

Bloom termination of the toxic dinoflagellate Alexandrium catenella: Vertical migration behavior, sediment infiltration, and benthic cyst yield.

PubMed

Brosnahan, Michael L; Ralston, David K; Fischer, Alexis D; Solow, Andrew R; Anderson, Donald M

2017-11-01

New resting cyst production is crucial for the survival of many microbial eukaryotes including phytoplankton that cause harmful algal blooms. Production in situ has previously been estimated through sediment trap deployments, but here was instead assessed through estimation of the total number of planktonic cells and new resting cysts produced by a localized, inshore bloom of Alexandrium catenella , a dinoflagellate that is a globally important cause of paralytic shellfish poisoning. Our approach utilizes high frequency, automated water monitoring, weekly observation of new cyst production, and pre- and post-bloom spatial surveys of total resting cyst abundance. Through this approach, new cyst recruitment within the study area was shown to account for at least 10.9% ± 2.6% (SE) of the bloom's decline, ∼ 5× greater than reported from comparable, sediment trap based studies. The observed distribution and timing of new cyst recruitment indicate that: (1) planozygotes, the immediate precursor to cysts in the life cycle, migrate nearer to the water surface than other planktonic stages and (2) encystment occurs after planozygote settlement on bottom sediments. Near surface localization by planozygotes explains the ephemerality of red surface water discoloration by A. catenella blooms, and also enhances the dispersal of new cysts. Following settlement, bioturbation and perhaps active swimming promote sediment infiltration by planozygotes, reducing the extent of cyst redistribution between blooms. The concerted nature of bloom sexual induction, especially in the context of an observed upper limit to A. catenella bloom intensities and heightened susceptibility of planozygotes to the parasite Amoebophrya , is also discussed.

Spontaneous alteration from Rathke's cleft cyst to craniopharyngioma--possible involvement of transformation between these pathologies.

PubMed

Ogawa, Yoshikazu; Watanabe, Mika; Tominaga, Teiji

2014-12-01

Both Rathke's cleft cyst and craniopharyngioma are considered to arise from the remnants of Rathke's diverticulum despite the quite different histological characteristics. These two lesions may consist of a disease spectrum extending from Rathke's cleft cyst to craniopharyngioma. However, in spite of increasing evidence of these intermediate histologies, very few cases of the actual transformation from Rathke's cleft cyst to craniopharyngioma have been reported in the same patient. A 47-year-old man suffered from recurrent visual dysfunction. Aspiration and partial cystectomy was performed to a suprasellar massive cystic lesion. The histological diagnosis was Rathke's cleft cyst with a small component of squamous metaplasia. Seven months later, the cyst was re-expanded. The cyst wall was irregularly thickened. Re-operation was performed, and the thickened anterior wall was widely removed. Postoperative histological examination showed multiplication of stratified squamous epithelia forming a papillary arrangement. Ki-67 staining showed positive cells randomly distributed not only in the basal layer but also in various epithelial layers, with a labeling index of more than 20 %. The histological diagnosis was squamous papillary type of craniopharyngioma with high potential of proliferation. Subsequent immunohistochemical examinations showed positive reaction to cytokeratin 8 only in the initial epithelium and negative in the latter epithelium. The present case was thought as an actual evidence of the proposed link between Rathke's cleft cyst and craniopharyngioma. Cytokeratin 8 could be the important examination to differentiate Rathke's cleft cyst from craniopharyngioma.

Simulation of lung alveolar epithelial wound healing in vitro.

PubMed

Kim, Sean H J; Matthay, Michael A; Mostov, Keith; Hunt, C Anthony

2010-08-06

The mechanisms that enable and regulate alveolar type II (AT II) epithelial cell wound healing in vitro and in vivo remain largely unknown and need further elucidation. We used an in silico AT II cell-mimetic analogue to explore and better understand plausible wound healing mechanisms for two conditions: cyst repair in three-dimensional cultures and monolayer wound healing. Starting with the analogue that validated for key features of AT II cystogenesis in vitro, we devised an additional cell rearrangement action enabling cyst repair. Monolayer repair was enabled by providing 'cells' a control mechanism to switch automatically to a repair mode in the presence of a distress signal. In cyst wound simulations, the revised analogue closed wounds by adhering to essentially the same axioms available for alveolar-like cystogenesis. In silico cell proliferation was not needed. The analogue recovered within a few simulation cycles but required a longer recovery time for larger or multiple wounds. In simulated monolayer wound repair, diffusive factor-mediated 'cell' migration led to repair patterns comparable to those of in vitro cultures exposed to different growth factors. Simulations predicted directional cell locomotion to be critical for successful in vitro wound repair. We anticipate that with further use and refinement, the methods used will develop as a rigorous, extensible means of unravelling mechanisms of lung alveolar repair and regeneration.

Lymphatic involvement in the histopathogenesis of mucous retention cyst.

PubMed

Kundu, Sukalyan; Cheng, Jun; Maruyama, Satoshi; Suzuki, Makoto; Kawashima, Hiroyuki; Saku, Takashi

2007-01-01

Mucous retention cyst results from extravasation of saliva. Our intent was to study the role of lymphatics in its pathogenesis. Twenty-three surgical specimens of mucous retention cyst of the lip were examined for involvement of lymphatic vessels by a comparative immunohistochemical demonstration of lymphatic and blood vascular endothelial cells, as well as lymphatic and salivary contents. Mucous retention cysts were histopathologically classified into three stages: early, intermediate, and advanced. In the early stage, there was diffuse extravasation of mucous material in the interstitium of the lamina propria or the submucosal layer of the oral mucosa. In the intermediate stage, lymphatics, which were clearly revealed and immunohistochemically distinguished from blood vessels by monoclonal antibody D2-40, were dilated and finally ruptured, leaving fragments of lymphatic walls in the periphery of mucous pools. In the advanced stage, thick cyst walls of granulation tissue were formed around mucous retention. Lymphatics were no longer involved in the granulation tissue wall, which was actively driven by blood vessel formation. The results suggest that the lymphatic rupture seems to contribute to the enlargement in the pathogenesis of mucous retention cyst.

Sublingual epidermoid cyst presenting with distinctive magnetic resonance imaging findings.

PubMed

Yoshida, Naohiro; Kodama, Kozue; Iino, Yukiko

2014-06-18

A case of sublingual epidermoid cyst presenting distinctive magnetic resonance imaging (MRI) findings is described. A 39-year-old man presented to our hospital with a three months progressive left submandibular swelling, difficulty moving his tongue, and snoring. Preoperative evaluation with MRI and fine needle aspiration cytology (FNAC) revealed that the heterogeneous cystic lesion contained the squamous cells, which is compatible with ectodermal tissue. The mass was located above the mylohyoid muscle and spread to the pharyngeal space. By considering the size, infection history, patient age, and location, the cyst was completely resected under general anesthesia via cervical approach without any complication. Histopathologically, the cyst wall was lined by stratified squamous epithelium with no skin appendage, suggesting an epidermoid cyst. Ultrasound (US), MRI and FNAC were very useful of the preoperative diagnosis for oral and sublingual lesion. The postoperative course was uneventful and without recurrence after 24 months. This case showed that epidermoid cysts formed the rarely heterogeneous cystic tumor and it underlined usefulness of preoperative diagnosis, such as US, MRI and FNAC for oral and sublingual tumor.

Lateral periodontal cysts arising in periapical sites: a report of two cases.

PubMed

Nikitakis, Nikolaos G; Brooks, John K; Melakopoulos, Ioannis; Younis, Rania H; Scheper, Mark A; Pitts, Mark A; Al-Mubarak, Hussain; Sklavounou, Alexandra

2010-10-01

The lateral periodontal cyst is an uncommon odontogenic developmental lesion and chiefly arises in the alveolar bone between the roots of a pair of erupted teeth or lateral to a tooth root. Two atypical cases of the lateral periodontal cyst occurring in periapical sites are reported. Both lesions presented as an incidental radiographic finding, appearing as an apical radiolucency with well-circumscribed sclerotic borders. One lesion, initially suspected to be of pulpal origin, persisted after endodontic therapy; the other case was first considered to be an odontogenic keratocyst. A biopsy was performed on each patient for lesional identity. Histopathologic assessment of each lesion was consistent with a lateral periodontal cyst and revealed thin, nonkeratinized epithelial linings containing nodular plaques and clear cells. The cyst walls were thickened and had minimal inflammation. The featured cases show that the lateral periodontal cyst is not always confined to the interradicular region and can masquerade as a lesion of endodontic origin. Aberrant cases warrant long-term surveillance. Copyright © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Coordinate expression of cytokeratins 7 and 14, vimentin, and Bcl-2 in canine cutaneous epithelial tumors and cysts.

PubMed

Pieper, Jason B; Stern, Adam W; LeClerc, Suzette M; Campbell, Karen L

2015-07-01

Forty-seven canine cutaneous epithelial tumors and cysts were examined to determine coordinate expression of cytokeratins 7 (CK7) and 14 (CK14), vimentin, and Bcl-2 using commercially available antibodies. Within non-affected normal skin adjacent to tumors or cysts, CK7 expression was observed in luminal cells in apocrine glands; CK14 expression was observed in the stratum basale, stratum spinosum, stratum granulosum, basal layer of outer root sheath, sebaceous glands, and myoepithelial cells of apocrine glands; vimentin expression was observed in dermal papilla and scattered non-epithelial cells within the epidermis; and Bcl-2 expression was observed in scattered non-epithelial cells in the epidermis and some apocrine glands. The pattern of expression of CK7 and CK14 in cases of adenocarcinoma of the apocrine gland of the anal sac (CK7+/CK14-) and hepatoid gland tumors (CK7-/CK14+) may prove useful for diagnostic purposes. Loss of expression of CK14 and vimentin, identifying myoepithelial cells, was observed in apocrine and ceruminous adenocarcinomas. Differences in patterns of expression of Bcl-2 were observed between infundibular keratinizing acanthomas compared to trichoepitheliomas. © 2015 The Author(s).

Toll-Like Receptor 4 Expression in the Epithelium of Inflammatory Periapical Lesions.

PubMed Central

Leonardi, R.; Perrotta, R.E.; Musumeci, G.; Crimi, S.; dos Santos, J.N.; Rusu, M.C.; Bufo, P.; Barbato, E.; Pannone, G.

2015-01-01

Toll-like receptors (TLR) are essential for the innate immune response against invading pathogens and have been described in immunocompetent cells of areas affected by periapical disease. Besides initiating the inflammatory response, they also directly regulate epithelial cell proliferation and survival in a variety of settings. This study evaluates the in situ expression of TLR4 in periapical granulomas (PG) and radicular cysts, focusing on the epithelial compartment. Twenty-one periapical cysts (PC) and 10 PG were analyzed; 7 dentigerous non-inflamed follicular cyst (DC) served as control. TLR4 expression was assessed by immunohistochemistry. TLR4 immunoreaction products were detected in the epithelium of all specimens, with a higher percentage of immunostained cells in PG. Although TLR4 overexpression was detected in both PG and PC, there were differences that seemed to be related to the nature of the lesion, since in PG all epithelial cells of strands, islands and trabeculae were strongly immunoreactive for TLR4, whereas in PC only some areas of the basal and suprabasal epithelial layers were immunostained. This staining pattern is consistent with the action of TLR4: in PG it could promote formation of epithelial cell rests of Malassez and in epithelial strands and islands the enhancement of cell survival, proliferation and migration, whereas in PC TLR4 could protect the lining epithelium from extensive apoptosis. These findings go some way towards answering the intriguing question of why many epithelial strands or islands in PG and the lining epithelium of apical cysts regress after non-surgical endodontic therapy, and suggest that TLR4 plays a key role in the pathobiology of the inflammatory process related to periapical disease. PMID:26708181

Toll-like receptor 4 expression in the epithelium of inflammatory periapical lesions. An immunohistochemical study.

PubMed

Leonardi, R; Perrotta, R E; Loreto, C; Musumeci, G; Crimi, S; Dos Santos, J N; Rusu, M C; Bufo, P; Barbato, E; Pannone, G

2015-10-26

Toll-like receptors (TLR) are essential for the innate immune response against invading pathogens and have been described in immunocompetent cells of areas affected by periapical disease. Besides initiating the inflammatory response, they also directly regulate epithelial cell proliferation and survival in a variety of settings. This study evaluates the in situ expression of TLR4 in periapical granulomas (PG) and radicular cysts, focusing on the epithelial compartment. Twenty-one periapical cysts (PC) and 10 PG were analyzed; 7 dentigerous non-inflamed follicular cyst (DC) served as control. TLR4 expression was assessed by immunohistochemistry. TLR4 immunoreaction products were detected in the epithelium of all specimens, with a higher percentage of immunostained cells in PG. Although TLR4 overexpression was detected in both PG and PC, there were differences that seemed to be related to the nature of the lesion, since in PG all epithelial cells of strands, islands and trabeculae were strongly immunoreactive for TLR4, whereas in PC only some areas of the basal and suprabasal epithelial layers were immunostained. This staining pattern is consistent with the action of TLR4: in PG it could promote formation of epithelial cell rests of Malassez and in epithelial strands and islands the enhancement of cell survival, proliferation and migration, whereas in PC TLR4 could protect the lining epithelium from extensive apoptosis. These findings go some way towards answering the intriguing question of why many epithelial strands or islands in PG and the lining epithelium of apical cysts regress after non-surgical endodontic therapy, and suggest that TLR4 plays a key role in the pathobiology of the inflammatory process related to periapical disease.

Frontal horn thin walled cysts in preterm neonates are benign

PubMed Central

Pal, B; Preston, P; Morgan, M; Rushton, D; Durbin, G

2001-01-01

BACKGROUND—Screening cranial ultrasound led to the discovery of isolated frontal horn cysts quite distinct from periventricular leucomalacia cysts.
AIM—To clarify their significance, incidence, characteristics, causal factors or aetiology, and effect on long term outcome.
DESIGN—A retrospective observational study of all first cranial ultrasound scans (total of 2914) performed during the period 1984-1994 inclusive found 21 neonates with smooth thin walled frontal horn cysts: 18 of 2629 scanned were of birth weight < 1500 g or gestation < 33 weeks, and three of 285 were > 33 weeks gestation. Sequential ultrasound, maternal records, and neonatal events were retrospectively assessed. In survivors, routine neurodevelopmental evaluations were obtained. Postmortem studies of one cyst were performed to determine the nature and origin of these lesions.
RESULTS—Of the 21 subjects, 15 had isolated frontal horn cysts and six had additional ultrasound scan abnormalities, including four with subependymal haemorrhage. The sonographic features of frontal horn cysts were of distinctive morphology (elliptical, smooth, thin walled, ranging in size from 3 to 20 mm) and position (adjacent to the tip of the anterior horns). The cysts enlarged and then regressed by a median corrected age of 2 months. Subjects of < 33 weeks gestation (n = 18) had a median birth weight of 1465g (range 720-1990) and median gestation of 30 weeks (range 24-32). There was no consistent perinatal course. The neurodevelopmental outcome in 10 of the 11 survivors with isolated frontal horn cysts was normal. Five subjects died from causes unrelated to brain pathology in the neonatal period, and one subject died after infancy. Histological examination of a cyst at autopsy in one additional subject subsequent to the period of study confirmed the cyst to be lined by neuroblasts and ependymal cells.
CONCLUSIONS—The incidence of frontal horn cysts in this low birthweight population was 7 per 1000 (0.7%) subjects scanned. They are present in the first week of life, enlarge, and resolve spontaneously. Survivors with isolated frontal horn cysts appear to have normal neurodevelopmental outcome. The prognosis of these distinct frontal horn cysts therefore appears to be benign.

 PMID:11668161

Multiple jaw cysts-unveiling the Gorlin-Goltz syndrome.

PubMed

Manjima, S; Naik, Zameera; Keluskar, Vaishali; Bagewadi, Anjana

2015-03-01

Gorlin-Goltz syndrome or basal cell nevus syndrome is a comparatively rare syndrome characterized by basal cell nevi, odontogenic keratocysts, and skeletal anomalies. Diagnosis is based on the major and minor clinical and radiographic criteria. Dentist plays a major role in the diagnosis of this disease due to the oral and maxillofacial manifestations of the syndrome. In some cases, jaw cysts are diagnosed by routine radiographs advised by the dentists. Odontogenic keratocysts in such syndromic patients will be multiple and extensive and in some cases results in cortical expansion and facial disfigurement. Thorough clinical examination and investigations prompt an early confirmation of the syndrome, which is very essential to avoid morbidity associated with the syndrome. Here, we report a case of multiple odontogenic cysts in a 16-year-old patient which later was diagnosed as a case of Gorlin Goltz syndrome.

Multiple jaw cysts-unveiling the Gorlin-Goltz syndrome

PubMed Central

Manjima, S.; Naik, Zameera; Keluskar, Vaishali; Bagewadi, Anjana

2015-01-01

Gorlin-Goltz syndrome or basal cell nevus syndrome is a comparatively rare syndrome characterized by basal cell nevi, odontogenic keratocysts, and skeletal anomalies. Diagnosis is based on the major and minor clinical and radiographic criteria. Dentist plays a major role in the diagnosis of this disease due to the oral and maxillofacial manifestations of the syndrome. In some cases, jaw cysts are diagnosed by routine radiographs advised by the dentists. Odontogenic keratocysts in such syndromic patients will be multiple and extensive and in some cases results in cortical expansion and facial disfigurement. Thorough clinical examination and investigations prompt an early confirmation of the syndrome, which is very essential to avoid morbidity associated with the syndrome. Here, we report a case of multiple odontogenic cysts in a 16-year-old patient which later was diagnosed as a case of Gorlin Goltz syndrome. PMID:25821359

FATE OF FLUORIDE-INDUCED SUBAMELOBLASTIC CYSTS IN DEVELOPING HAMSTER MOLAR TOOTH GERMS

PubMed Central

Lyaruu, DM; Alberga, JMR; Kwee, NCH; Bervoets, TJM; Bronckers, ALJJ; DenBesten, PK

2016-01-01

White opacities and pits are developmental defects in enamel caused by high intake of fluoride (F) during amelogenesis. We tested the hypothesis that these enamel pits develop at locations where F induces the formation of sub-ameloblastic cysts. We followed the fate of these cysts during molar development over time. Mandibles from hamster pups injected with 20 mg NaF/kg at postnatal day 4 were excised from 1 h after injection till shortly after tooth eruption, 8 days later. Tissues were histologically processed and cysts located and measured. Cysts were formed at early secretory stage and transitional stage of amelogenesis and detected as early 1 h after injection. The number of cysts increased from 1 to almost 4 per molar during the first 16 h post-injection. The size of the cysts was about the same, i.e., 0.46±0.29 ×106 μm3 at 2hr and 0.50±0.35×106 μm3 at 16 h post-injection. By detachment of the ameloblasts the forming enamel surface below the cyst was cell-free the first 16 h post-injection. With time new ameloblasts repopulated and covered the enamel surface in the cystic area. Three days after injection all cysts had disappeared and the integrity of the ameloblastic layer restored. After eruption, white opaque areas with intact enamel surface were found occlusally at similar anatomical locations as late secretory stage cysts were seen pre-eruptively. We conclude that at this moderate F dose, the opaque sub-surface defects with intact surface enamel (white spots) are the consequence of the fluoride-induced cystic lesions formed earlier under the late secretory–transitional stage ameloblasts. PMID:21277565

Cystic urogenital anomalies in ferrets (Mustela putorius furo).

PubMed

Li, X; Fox, J G; Erdman, S E; Lipman, N S; Murphy, J C

1996-03-01

Single or multiple semispherical to bilobulated fluid-filled cystic structures of variable size were observed on the dorsal aspects of the urinary bladder of four male and two female ferrets (Mustela putorius furo). All ferrets had been neutered. On physical examination, the cysts were palpated as caudal abdominal masses. Three of the six ferrets presented with dysuria, and two ferrets had signs compatible with endocrine dysfunction. Adrenal cortical hyperplasia or neoplasia were observed in all of the five ferrets examined. Sex hormones assayed in one of the six ferrets revealed elevated levels of serum estrodiol. The posterior aspect of the cysts was located on and/or attached to the trigone or neck of the bladder, with variable intraluminal communication with the bladder and/or the urethra. The anterior aspect of the cysts projected dorsally or dorsocranially into the caudal abdomen. The cysts were thin walled and contained urinelike fluid (n = 5) or viscous yellow fluid (n = 1). Histologically, the cyst walls were composed of three layers, epithelium, muscle, and serosa, with fibrovascular stroma between layers. The epithelium consisted of simple to stratified transitional, columnar, or squamous epithelial cells. The muscular layer consisted of intermittent bundles and/or single to double layers of continuous to discontinuous smooth muscle. The serosal layer consisted of loose fibrous stroma covered by flattened mesothelial cells. The cystic anomalies in these ferrets were most likely derived from the urogenital glands/ducts or other remnants.

Actual Proliferating Index and p53 protein expression as prognostic marker in odontogenic cysts.

PubMed

Gadbail, A R; Chaudhary, M; Patil, S; Gawande, M

2009-10-01

The purpose of this study was to evaluate the biological aggressiveness of odontogenic keratocyst/keratocystic odontogenic tumour (KCOT), radicular cyst (RC) and dentigerous cyst (DC) by observing the actual proliferative activity of epithelium, and p53 protein expression. The actual proliferative activity was measured by Ki-67 Labelling Index and argyrophilic nucleolar organizing regions (AgNOR) count per nucleus. The p53 protein expression was also evaluated. Ki-67 positive cells were observed higher in suprabasal cell layers of KCOT with uniform distribution, a few of them were predominantly observed in basal cell layer in RC and DC. The AgNOR count was significantly higher in suprabasal cell layers of KCOT. The actual proliferative activity was noted to be higher in suprabasal cell layers of KCOT. The p53 immunolabelling was dense and scattered in basal and suprabasal cell layers in KCOT. The weakly stained p53 positive cells were observed diffusely distributed in KCOT, whereas they were mainly seen in basal cell layer of RC and DC. The quantitative and qualitative differences of the proliferative activity and the p53 protein expression in sporadic KCOT may be associated with intrinsic growth potential that could play a role in its development and explain locally aggressive biological behaviour. AgNOR count and p53 protein detection in odontogenic lesions can be of great consequence to predict the biological behaviour and prognosis.

Branchial cleft-like cysts in Hashimoto's thyroiditis: A case report and literature review.

PubMed

Miyazaki, Masaya; Kiuchi, Shizuka; Fujioka, Yasunori

2016-05-01

We report an extremely rare case of branchial cleft-like cysts in Hashimoto's thyroiditis. The patient was a 77-year-old man with a growing mass in the anterior neck. Ultrasonography and computed tomography revealed a cystic lesion with septum in the left thyroid and multiple small cystic lesions in the right thyroid. Lymph node swelling of the cervical region, supraclavicular fossa and submandibular region was also observed. Left thyroidectomy and lymph node dissection were performed. Histologically, cysts were lined by stratified squamous epithelium and dense lymphoid tissue having conspicuous follicle formation surrounded the epithelial lining. Solid cell nest (SCN)-like aggregations were seen in the thyroid parenchyma adjacent to the cyst walls and a small number of thyroid follicles were observed in the fibrous wall. Immunohistochemically, it is suggested that both the cyst lining and SCN-like aggregations are originally from thyroid follicles. Although, the exact histogenesis of branchial cleft-like cysts remains unclear, there are probably two different processes for its development, one is of branchial cleft origin and the other is mere squamous metaplasia, while in our case the latter is suggested. Herein, we report our new case and update information about branchial cleft-like cysts that appears in the literature. © 2016 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

Dermoid Cysts of the Floor of the Mouth: Two Case Reports

PubMed Central

Makos, Christos; Noussios, George; Peios, Marinos; Gougousis, Spyridon; Chouridis, Pantelis

2011-01-01

Dermoid cysts in the floor of the mouth may be congenital or acquired. The congenital form, according to the main theory, originates from embryonic cells of the 1st and 2nd branchial arch. The acquired form may be due to traumatic or iatrogenic causes and as a result of the occlusion of a sebaceous gland duct. Its occurrence is less and is estimated to be from 1.6 to 6.4% of the dermoid cysts of the body in adults and 0.29% of the head and neck tumors occurring in children. They may also be classified as anatomical and histological. Anatomically, they are divided into median genioglossal, median geniohyoid, and lateral cysts, while histologically they are divided into epidermoid, dermoid cysts and teratomas. Clinically, a distinction between supra and inferior type as well as between central and lateral type is proposed in relation to themylohyoidmuscle and themidline, respectively. Histologically, an estimation of dermoid, epidermoid, and teratoid cysts is reported. Enucleation via intraoral and/or extraoral approach is the method of treatment. Two case reports of dermoid cysts in the floor of the mouth are presented in this paper, and an evaluation with regard to pathology, clinical findings, differential diagnosis, and treatment is discussed. PMID:21922020

Analysis of survival and hatching transcriptomes from potato cyst nematodes, Globodera rostochiensis and G. pallida.

PubMed

Duceppe, Marc-Olivier; Lafond-Lapalme, Joël; Palomares-Rius, Juan Emilio; Sabeh, Michaël; Blok, Vivian; Moffett, Peter; Mimee, Benjamin

2017-06-20

Potato cyst nematodes (PCNs), Globodera rostochiensis and G. pallida, cause important economic losses. They are hard to manage because of their ability to remain dormant in soil for many years. Although general knowledge about these plant parasitic nematodes has considerably increased over the past decades, very little is known about molecular events involved in cyst dormancy and hatching, two key steps of their development. Here, we have studied the progression of PCN transcriptomes from dry cysts to hatched juveniles using RNA-Seq. We found that several cell detoxification-related genes were highly active in the dry cysts. Many genes linked to an increase of calcium and water uptake were up-regulated during transition from dormancy to hydration. Exposure of hydrated cysts to host plant root exudates resulted in different transcriptional response between species. After 48 h of exposure, G. pallida cysts showed no significant modulation of gene expression while G. rostochiensis had 278 differentially expressed genes. The first G. rostochiensis significantly up-regulated gene was observed after 8 h and was coding for a transmembrane metalloprotease. This enzyme is able to activate/inactivate peptide hormones and could be involved in a cascade of events leading to hatching. Several known effector genes were also up-regulated during hatching.

Interplay between the parasite Amoebophrya sp. (Alveolata) and the cyst formation of the red tide dinoflagellate Scrippsiella trochoidea.

PubMed

Chambouvet, Aurélie; Alves-de-Souza, Catharina; Cueff, Valérie; Marie, Dominique; Karpov, Sergey; Guillou, Laure

2011-10-01

Syndiniales (Alveolata) are marine parasites of a wide range of hosts, from unicellular organisms to Metazoa. Many Syndiniales obligatorily kill their hosts to accomplish their life cycle. This is the case for Amoebophrya spp. infecting dinoflagellates. However, several dinoflagellate species known to be infected by these parasites produce diploid resting cysts as part of their life history. These resting cysts may survive several seasons in the sediment before germinating. How these parasites survive during the dormancy of their host remained an open question. We successfully established infections by Amoebophrya sp. in the red tide dinoflagellate Scrippsiella trochoidea. This host strain was homothallic and able to continuously produce typical calcified cysts covered by calcareous spines. Presence of the parasite significantly speeded up the host cyst production, and cysts produced were the only cells to resist infections. However, some of them were clearly infected, probably earlier in their formation. After 10 months, cysts produced in presence of the parasite were able to germinate and new infective cycles of the parasite were rapidly observed. Thus, a very novel relationship for protists is demonstrated, one in which parasite and host simultaneously enter dormancy, emerging months later to propagate both species. Copyright © 2011 Elsevier GmbH. All rights reserved.

Scrotal calcinosis: idiopathic or dystrophic?

PubMed

Dubey, Suparna; Sharma, Rajeev; Maheshwari, Veena

2010-02-15

Scrotal calcinosis is a rare benign local process characterized by multiple, painless, hard scrotal nodules in the absence of any systemic metabolic disorder. Histological examination reveals extensive deposition of calcium in the dermis, which may be surrounded by histiocytes and an inflammatory giant cell reaction. Numerous theories have been propounded to explain the pathogenesis of this condition, but the principal debate revolves around whether the calcium is deposited at the site of previous epithelial cysts or the calcified nodules are purely idiopathic. This is the largest study of scrotal calcinosis to date with 100 cases, on which clinical, biochemical, radiological, cytopathological, and histopathological examinations were conducted. The histological picture shows a continuous spectrum of changes ranging from intact epithelial cysts (41.0%) - both normal and inflamed; through inflamed cysts containing calcific material in the lumen but with intact cyst wall (53.0%); calcified inflamed cysts with partial epithelial lining (11.0%); to 'naked' calcium deposits lying in the dermis (100%), sometimes compressing surrounding collagen fibres to form a pseudocyst (56.0%). The presence of normal values of calcium and phosphorus along with this spectrum of changes in histology both support the theory that these form by dystrophic calcification of epithelial cysts in a progression that involves inflammation, rupture, calcification and obliteration of the cyst wall.

In planta processing and glycosylation of a nematode CLE effector and its interaction with a CLV2-like receptor to promote parasitism

USDA-ARS?s Scientific Manuscript database

Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ESR (CLE)-like proteins have been identified in several cyst nematodes including the potato cyst nematode (PCN); however, th...

Characterization of the local immune response to cyst antigens during the acute and elimination phases of primary murine giardiasis.

PubMed

Abdul-Wahid, Aws; Faubert, Gaétan

2008-05-01

During the course of a giardial infection, the host's immune system is presented with a variety of Giardia antigens as trophozoites differentiate, through encysting cells, to form the infective cysts. Previous studies examining the host's immune response during giardial infections have focused on trophozoite-derived antigens (Ags). In this study, we were interested to determine if the host's immune system reacts to cyst Ags during the acute and elimination phases, when there is cyst shedding. For this purpose, we used antigenic extracts from trophozoites (Troph), encysting cells (ENC), and purified giardial cyst walls (PCW), as well as purified recombinant cyst wall protein 2 (rCWP2). Comparative analysis of the parasite extracts using SDS-PAGE analysis and surface-enhanced laser desorption/ionization time of flight mass spectrometry resulted in the detection of 175 protein entities, of which 26 were Troph-specific proteins, 17 ENC-specific proteins, and 31 were PCW-specific proteins. On the other hand, we detected 34 proteins shared between Troph and ENC, 19 proteins that were shared between ENC and PCW, and 29 proteins that were common to Troph and PCW. Finally, we detected 19 proteins that were shared by all three extract samples. BALB/c mice were infected with 10(5)Giardia muris cysts and sacrificed either at the acute or elimination phases of infection (days 12 and 40, respectively), and lymphocytes were isolated from the Peyer's patches (PP). Using flow cytometry, we detected significant increases in the number of PP-derived CD4(+) and CD19(+), but not CD8(+) lymphocytes. Quantification of the number of mucosal IL-4 and IFN-gamma secreting T-lymphocytes by enzyme-linked immunosorbent spot assay showed that these cells reacted by secreting similar levels of IL-4 and IFN-gamma, regardless of the Ag or the phase of infection. Analysis of intestinal humoral immune responses by ELISA resulted in the detection of Ag-specific IgA and IgG intestinal antibodies. Regardless of the Ag tested, a trend was consistently observed where the concentration of local antibodies was found to be slightly increased by the acute phase, where we detected approximately 200microg/mg of specific IgA and approximately 300ng/ml of specific IgG in intestinal lavage of infected mice. By the elimination phase, the amount of specific antibodies was found to increase to approximately 600microg/mg of specific IgA and approximately 1300ng/ml of specific IgG antibodies. Finally, we tested the biological activity of these antibodies and found that they were able to reduce the ability of trophozoites to differentiate into cysts in vitro. Collectively, we believe these results demonstrate for the first time the existence of significant cellular and humoral immune responses against Giardia cyst Ags that may contribute to the reduction of cyst shedding in infected animals.

An efficient method for extraction of astaxanthin from green alga Haematococcus pluvialis.

PubMed

Sarada, R; Vidhyavathi, R; Usha, D; Ravishankar, G A

2006-10-04

Haematococcus pluvialis is one of the potent organisms for production of astaxanthin, a high value ketocarotenoid. Astaxanthin is accumulated in thick-walled cyst cells of Haematococcus. The thick cell wall is made up of sporopollenin-like material, algaenan, which hinders solvent extraction of astaxanthin. In the present study, an improved method for extraction of astaxanthin without homogenization of cells is reported. Extractability of astaxanthin from cyst cells was evaluated by treating cells with various solvents and pretreating the cells with organic and mineral acids at 70 degrees C followed by acetone extraction. Hydrochloric acid treatment facilitated 86-94% extractability of astaxanthin. Treatment time, temperature, and concentration of the acid were found to be critical factors for maximum extractability. The treatment did not affect the astaxanthin ester profile and the treated cells can be preserved until further use.

Stable carbon isotope fractionation of organic cyst-forming dinoflagellates: Evaluating the potential for a CO2 proxy

NASA Astrophysics Data System (ADS)

Hoins, Mirja; Van de Waal, Dedmer B.; Eberlein, Tim; Reichart, Gert-Jan; Rost, Björn; Sluijs, Appy

2015-07-01

Over the past decades, significant progress has been made regarding the quantification and mechanistic understanding of stable carbon isotope fractionation (13C fractionation) in photosynthetic unicellular organisms in response to changes in the partial pressure of atmospheric CO2 (pCO2). However, hardly any data is available for organic cyst-forming dinoflagellates while this is an ecologically important group with a unique fossil record. We performed dilute batch experiments with four harmful dinoflagellate species known for their ability to form organic cysts: Alexandrium tamarense, Scrippsiella trochoidea, Gonyaulax spinifera and Protoceratium reticulatum. Cells were grown at a range of dissolved CO2 concentrations characterizing past, modern and projected future values (∼5-50 μmol L-1), representing atmospheric pCO2 of 180, 380, 800 and 1200 μatm. In all tested species, 13C fractionation depends on CO2 with a slope of up to 0.17‰ (μmol L)-1. Even more consistent correlations were found between 13C fractionation and the combined effects of particulate organic carbon quota (POC quota; pg C cell-1) and CO2. Carbon isotope fractionation as well as its response to CO2 is species-specific. These results may be interpreted as a first step towards a proxy for past pCO2 based on carbon isotope ratios of fossil organic dinoflagellate cysts. However, additional culture experiments focusing on environmental variables other than pCO2, physiological underpinning of the recorded response, testing for possible offsets in 13C values between cells and cysts, as well as field calibration studies are required to establish a reliable proxy.

Ovarian cysts in MRL/MpJ mice are derived from the extraovarian rete: a developmental study

PubMed Central

Lee, Shin-Hyo; Ichii, Osamu; Otsuka, Saori; Yaser Hosney, Elewa; Namiki, Yuka; Hashimoto, Yoshiharu; Kon, Yasuhiro

2011-01-01

MRL/MpJ (MRL) mice, commonly used as a model for autoimmune disease, have a high frequency of ovarian cysts originating from the rete ovarii. In the present study, to clarify how the rete ovarii, which are remnants of mesonephric tubules during embryogenesis, progress to cystic formation with aging, the morphology of MRL rete ovarii was analyzed and compared with that of normal C57BL/6N (B6) mice. In B6 mice, the rete ovarii consisted of a series of tubules, including the extraovarian rete (ER), the connecting rete (CR), and the intraovarian rete (IR), based on their location. Whereas the ER of B6 mice was composed of highly convoluted tubules lined by both ciliated and non-ciliated epithelia, the tubules in the CR and IR had only non-ciliated cells. In MRL mice, dilations of the rete ovarii initiated from the IR rather than the ER or CR. Although the histological types of cells lining the lumen of the rete ovarii were the same as those in B6 mice, the ER in MRL mice showed a variety in morphology. In particular, the connections between the ER and ovary tended to disappear with increasing age and the development of ovarian cysts. Furthermore, the epithelium lining the large ovarian cysts in MRL mice had ciliated cells forming the cluster. On the basis of these findings, it is suggested that cystic changes of the rete ovarii in MRL mice are caused by the dilations of the IR with invasion of the ER and CR into the ovarian medulla. These data provide new pathological mechanisms for ovarian cyst formation. PMID:21951275

Distinct patterns of primary and motile cilia in Rathke's cleft cysts and craniopharyngioma subtypes.

PubMed

Coy, Shannon; Du, Ziming; Sheu, Shu-Hsien; Woo, Terri; Rodriguez, Fausto J; Kieran, Mark W; Santagata, Sandro

2016-12-01

Cilia are highly conserved organelles, which serve critical roles in development and physiology. Motile cilia are expressed in a limited range of tissues, where they principally regulate local extracellular fluid dynamics. In contrast, primary cilia are expressed by many vertebrate cell types during interphase, and are intimately involved in the cell cycle and signal transduction. Notably, primary cilia are essential for vertebrate hedgehog pathway activity. Improved detection of motile cilia may assist in the diagnosis of some pathologic entities such as Rathke's cleft cysts, whereas characterizing primary cilia in neoplastic tissues may implicate cilia-dependent signaling pathways as critical for tumorigenesis. We show that immunohistochemistry for the nuclear transcription factor FOXJ1, a master regulator of motile ciliogenesis, robustly labels the motile ciliated epithelium of Rathke's cleft cysts. FOXJ1 expression discriminates Rathke's cleft cysts from entities in the sellar/suprasellar region with overlapping histologic features such as craniopharyngiomas. Co-immunohistochemistry for FOXJ1 and markers that highlight motile cilia such as acetylated tubulin (TUBA4A) and the small GTPase ARL13B further enhance the ability to identify diagnostic epithelial cells. In addition to highlighting motile cilia, ARL13B immunohistochemistry also robustly highlights primary cilia in formalin-fixed paraffin-embedded sections. Primary cilia are present throughout the neoplastic epithelium of adamantinomatous craniopharyngioma, but are limited to basally oriented cells near the fibrovascular stroma in papillary craniopharyngioma. Consistent with this differing pattern of primary ciliation, adamantinomatous craniopharyngiomas express significantly higher levels of SHH, and downstream targets such as PTCH1 and GLI2, compared with papillary craniopharyngiomas. In conclusion, motile ciliated epithelium can be readily identified using immunohistochemistry for FOXJ1, TUBA4A, and ARL13B, facilitating the diagnosis of Rathke's cleft cysts. Primary cilia can be identified by ARL13B immunohistochemistry in routine pathology specimens. The widespread presence of primary cilia in adamantinomatous craniopharyngioma implicates cilia-dependent hedgehog signaling in the pathogenesis of adamantinomatous craniopharyngioma.

Distinct Patterns of Primary and Motile Cilia in Rathke’s Cleft Cysts and Craniopharyngioma Subtypes

PubMed Central

Coy, Shannon; Du, Ziming; Sheu, Shu-Hsien; Woo, Terri; Rodriguez, Fausto J.; Kieran, Mark W.; Santagata, Sandro

2017-01-01

Cilia are highly conserved organelles which serve critical roles in development and physiology. Motile cilia are expressed in a limited range of tissues, where they principally regulate local extracellular fluid dynamics. In contrast, primary cilia are expressed by many vertebrate cell types during interphase, and are intimately involved in the cell cycle and signal transduction. Notably, primary cilia are essential for vertebrate hedgehog pathway activity. Improved detection of motile cilia may assist in the diagnosis of some pathologic entities such as Rathke’s cleft cysts while characterizing primary cilia in neoplastic tissues may implicate cilia-dependent signaling pathways as critical for tumorigenesis. We show that immunohistochemistry for the nuclear transcription factor FOXJ1, a master regulator of motile ciliogenesis, robustly labels the motile ciliated epithelium of Rathke’s cleft cysts. FOXJ1 expression discriminates Rathke’s cleft cysts from entities in the sellar/suprasellar region with overlapping histologic features such as craniopharyngiomas. Co-immunohistochemistry for FOXJ1 and markers that highlight motile cilia such as acetylated tubulin (TUBA4A) and the small GTPase ARL13B further enhance the ability to identify diagnostic epithelial cells. In addition to highlighting motile cilia, ARL13B immunohistochemistry also robustly highlights primary cilia in formalin-fixed paraffin-embedded sections. Primary cilia are present throughout the neoplastic epithelium of adamantinomatous craniopharyngioma, but are limited to basally oriented cells near the fibrovascular stroma in papillary craniopharyngioma. Consistent with this differing pattern of primary ciliation, adamantinomatous craniopharyngiomas express significantly higher levels of SHH, and downstream targets such as PTCH1 and GLI2, compared to papillary craniopharyngiomas. In conclusion, motile ciliated epithelium can be readily identified using immunohistochemistry for FOXJ1, TUBA4A and ARL13B, facilitating the diagnosis of Rathke’s cleft cyst. Primary cilia can be identified by ARL13B immunohistochemistry in routine pathology specimens. The widespread presence of primary cilia in adamantinomatous craniopharyngioma implicates cilia-dependent hedgehog signaling in the pathogenesis of adamantinomatous craniopharyngioma. PMID:27562488

p53 expression and mutation analysis of odontogenic cysts with and without dysplasia.

PubMed

Cox, Darren P

2012-01-01

Overexpression of p53 protein is well described in odontogenic cystic lesions (OCLs), including those with epithelial dysplasia; however, most p53 antibodies stain both wild-type and mutated p53 protein and may not reflect genotype. Direct sequencing of the p53 gene has not identified mutations in OCLs with dysplasia. The purpose of this study was to determine the molecular basis of p53 expression in several types of OCLs with and without dysplasia. The study material comprised 13 OCLs: odontogenic keratocyst (n = 5), orthokeratinized odontogenic cyst (n = 5), dentigerous cyst (n = 2), lateral periodontal cyst (n = 1), and unspecified developmental odontogenic cyst (UDOC) (n = 1). Five of these had features of mild or moderate epithelial dysplasia. One intraosseous squamous cell carcinoma (SCC) that was believed to have arisen from an antecedent dysplastic orthokeratinized OC was also included. Immunohistochemistry was performed using the DO7 monoclonal antibody that recognizes wild-type and mutated p53. DNA was extracted from microdissected tissue for all samples and exons 4 to 8 of the p53 gene direct sequenced. In 4 of 5 OCLs with dysplasia there was strong nuclear staining of basal and suprabasal cells. In all cases without dysplasia, nuclear expression in basal cells was either negative or weak and was absent in suprabasal cell nuclei. A mutation in exon 6 of the p53 gene (E224D) was identified in both the dysplastic orthokeratinized OC and the subsequent intraosseous SCC. OCLs with features of dysplasia show increased expression of p53 protein that does not reflect p53 mutational status. One dysplastic OC shared the same p53 mutation with a subsequent intraosseous SCC, indicating that p53 mutation may be associated with malignant transformation in this case. Copyright © 2012 Elsevier Inc. All rights reserved.

THE NEOPLASTIC POTENTIALITIES OF MOUSE EMBRYO TISSUES

PubMed Central

Smith, William E.

1947-01-01

Epithelial tumors have been readily obtained by the implantation of embryo stomach tissue together with olive oil containing methylcholanthrene (with or without Scharlach R) in adult mice of homologous strain. The implanted tissue from the squamous portion of the stomach rapidly encysted the oil, and benign and malignant papillomas and squamous cell carcinomas soon arose from the stratified squamous lining of the cysts. Bits of the glandular portion of the stomach also formed cysts, but the gland cells underwent metaplasia in response to the carcinogen, altering first to transitional epithelium and then to a stratified squamous layer. So swiftly did these changes take place that nearly all of the tumors took origin from epithelium that had already become stratified and squamous, and the growths themselves were of this type. A single transitional cell carcinoma and an adenoacanthoma were procured, but no adenocarcinomas; nor did any benign papillomas develop, though they often resulted from the action of methylcholanthrene on the squamous portion of the embryo stomach. Search failed to disclose any distinctive precancerous changes in the gastric tissue. Five of the cancers were transplanted and they grew in every host. No tumors arose from any of the numerous control implants. Those consisting of glandular tissue formed cysts lined partly with columnar epithelium secreting mucus and partly with tubular glands equipped with chief and parietal cells in good condition. Pepsin and rennin were found in the fluid contained in these cysts, but no free hydrochloric acid. The enzymes were present also when the cysts contained methylcholanthrene and the glands had not yet been wholly replaced by metaplastic epithelium. The tumors appeared months sooner than when methylcholanthrene is injected into the stomach of adult animals or given by mouth; some of them were well established after 5 or 6 weeks. They arose regularly when the requisite experimental conditions were provided. The utilization of transplanted embryo tissue provides a means whereby gastric tumors free from bacterial infection can be procured swiftly and easily. PMID:19871629

Oral lymphoepithelial cyst: A clinicopathological study of 26 cases and review of the literature.

PubMed

Sykara, Maria; Ntovas, Panagiotis; Kalogirou, Eleni-Marina; Tosios, Konstantinos I; Sklavounou, Alexandra

2017-08-01

Τo describe the clinicopathological features of 26 oral lymphoepithelial cysts (LECs) and review the literature. Twenty-six cases of oral LECs diagnosed during a 37-year period were retrospectively collected. The patients' gender and age, as well as the main clinical features of the cysts were retrieved from the requisition forms. The main microscopic features were recorded after reevaluation of all cases. Pubmed and Google Scholar electronic databases were searched with the key word "oral LEC". Inclusion criteria were the microscopic confirmation of LEC diagnosis and the report at least two of three main clinical features (gender, age and cyst's location). The 26 oral LECs represented 0.08% of 31,564 biopsies accessioned during the study period. They affected 25 patients, 14 females and 11 males with a mean age of 33.04±9.81 years. They appeared as smooth (92%) nodules, with soft (24%) or firm (76%) consistency and normal (28%), yellow to normal (20%), yellow (32%) or white (20%) hue, in the tongue (69.23%) or the floor of mouth (30.77%). They were covered by parakeratinized squamous (92.31%) or non-keratinized (7.69%) epithelium and contained desquamated epithelial cells, amorphous eosinophilic material and/or inflammatory cells (100%). The lymphoid tissue surrounded the cystic cavity partially (34.62%) or completely (65.38%), often in a follicular pattern with prominent germinal centers (53.85%). Literature review yielded 316 cases of oral LECs derived from 25 case reports, 3 case studies/retrospective studies with detailed information for each case and 7 studies with summarized data. Oral LEC is a pathologic entity with discrete clinical presentation that is, however, commonly misdiagnosed in clinical practice as other, mostly benign, entities. Its pathogenesis remains obscure, as its clinicopathologic features are consistent with both theories suggested up to date. Key words: Oral lymphoepithelial cyst; developmental cyst; non odontogenic cyst; lymphoid tissue; oral tonsil.

Akap350 Recruits Eb1 to The Spindle Poles, Ensuring Proper Spindle Orientation and Lumen Formation in 3d Epithelial Cell Cultures.

PubMed

Almada, Evangelina; Tonucci, Facundo M; Hidalgo, Florencia; Ferretti, Anabela; Ibarra, Solange; Pariani, Alejandro; Vena, Rodrigo; Favre, Cristián; Girardini, Javier; Kierbel, Arlinet; Larocca, M Cecilia

2017-11-02

The organization of epithelial cells to form hollow organs with a single lumen requires the accurate three-dimensional arrangement of cell divisions. Mitotic spindle orientation is defined by signaling pathways that provide molecular links between specific spots at the cell cortex and astral microtubules, which have not been fully elucidated. AKAP350 is a centrosomal/Golgi scaffold protein, implicated in the regulation of microtubule dynamics. Using 3D epithelial cell cultures, we found that cells with decreased AKAP350 expression (AKAP350KD) formed polarized cysts with abnormal lumen morphology. Analysis of mitotic cells in AKAP350KD cysts indicated defective spindle alignment. We established that AKAP350 interacts with EB1, a microtubule associated protein that regulates spindle orientation, at the spindle poles. Decrease of AKAP350 expression lead to a significant reduction of EB1 levels at spindle poles and astral microtubules. Conversely, overexpression of EB1 rescued the defective spindle orientation induced by deficient AKAP350 expression. The specific delocalization of the AKAP350/EB1complex from the centrosome decreased EB1 levels at astral microtubules and lead to the formation of 3D-organotypic structures which resembled AKAP350KD cysts. We conclude that AKAP350 recruits EB1 to the spindle poles, ensuring EB1 presence at astral microtubules and proper spindle orientation during epithelial morphogenesis.

Extreme lateral approach in a case of acute-onset quadriplegia due to high cervical neurenteric cyst.

PubMed

Abhishek, Agrawal; Anushree, Agrawal; Patir, Rana; Sehgal, A D

2007-01-01

Spinal neurenteric cysts are very rare intradural developmental lesions, predominantly localized anterior to the cervical cord and arising from misplaced endodermal cells in the 3rd week of embryonic life. An acute onset of symptoms can occur due to hemorrhage, but has not as yet been reported in relation to infection in the cyst. We report an 18-year-old male who presented with a rapid onset of respiratory distress and quadriplegia over a period of 6 h requiring intubation and ventilatory support. There was no respiratory effort with a dense sensory level from the neck. MRI of the cervical spine revealed an intradural extramedullary ventrally located cystic lesion at the C(2-3) level. There was no evidence of systemic infection elsewhere in the body. The lesion was radically excised using an extreme lateral approach as it provided excellent visualization of the cyst, thus permitting safe dissection without retraction of the cord. The cyst was tense and the contents turbid, thick, creamy and mucinous without any evidence of fresh or altered blood. Histopathological examination confirmed the cyst to be a neurenteric cyst. The cystic fluid, which was sent for culture, grew coagulase-negative Staphylococcus aureus. This is the first documented case of rapid neurological deterioration due to infection in a neurenteric cyst. In spite of an early effective surgical management, outcome was poor due to the rapid and profound neurological deficit. Copyright (c) 2007 S. Karger AG, Basel.

Role of resting cysts in Chilean Alexandrium catenella dinoflagellate blooms revisited.

PubMed

Mardones, Jorge I; Bolch, Chris; Guzmán, Leonardo; Paredes, Javier; Varela, Daniel; Hallegraeff, Gustaaf M

2016-05-01

The detection of sparse Alexandrium catenella-resting cysts in sediments of southern Chilean fjords has cast doubts on their importance in the recurrence of massive toxic dinoflagellate blooms in the region. The role of resting cysts and the existence of different regional Chilean populations was studied by culturing and genetic approaches to define: (1) cyst production; (2) dormancy period; (3) excystment success; (4) offspring viability and (5) strain mating compatibility. This study newly revealed a short cyst dormancy (minimum 69 days), the role of key abiotic factors (in decreasing order salinity, irradiance, temperature and nutrients) controlling cyst germination (max. 60%) and germling growth rates (up to 0.36-0.52div.day -1 ). Amplified fragment length polymorphism (AFLP) characterization showed significant differences in genetic distances (GD) among A. catenella populations that were primarily determined by the geographical origin of isolates and most likely driven by oceanographic dispersal barriers. A complex heterothallic mating system pointed to variable reproductive compatibility (RCs) among Chilean strains that was high among northern (Los Lagos/North Aysén) and southern populations (Magallanes), but limited among the genetically differentiated central (South Aysén) populations. Field cyst surveys after a massive 2009 bloom event revealed the existence of exceptional high cyst densities in particular areas of the fjords (max. 14.627cystscm -3 ), which contrast with low cyst concentrations (<221.3cystscm -3 ) detected by previous oceanographic campaigns. In conclusion, the present study suggests that A. catenella resting cysts play a more important role in the success of this species in Chilean fjords than previously thought. Results from in vitro experiments suggest that pelagic-benthic processes can maintain year-round low vegetative cell concentrations in the water column, but also can explain the detection of high cysts aggregations after the 2009-bloom event. Regional drivers that lead to massive outbreaks, however, are still unknown but potential scenarios are discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

Telangiectatic osteosarcoma--a case report.

PubMed Central

Suh, Y. L.; Chi, J. G.

1989-01-01

Telangiectatic osteosarcoma is a rare and special variant of osteogenic sarcoma with distinct radiologic, gross and microscopic features. This tumor is predominantly lytic, destructive tumor without sclerosis on roentgenogram, and is soft and cystic on gross examination. Histologically aneurysmally dilated spaces lined or traversed by stromal cells producing osteoid are noted. This report concerns a case of telangiectatic osteosarcoma occurring in a 7 years old boy. He presented with pathologic fracture of the right distal tibia, followed by a purely lytic lesion on X-ray examination. This lesion recurred five times during a span of one year. Microscopic features of the biopsy specimen was difficult to differentiate from aneurysmal bone cyst because of prominant blood-filled cyst formation. It was finally identified as osteosarcoma from the below-knee amputation specimen through the close examination for anaplastic osteoid-producing stromal cells in the septa that separate the blood cysts. PMID:2597366

Circumferential Ciliary Body Cysts Presenting as Acute Pigment Dispersion and Ocular Hypertension.

PubMed

Sarıgül Sezenöz, Almila; Güngör, Sirel Gür; Kıratlı, Hayyam; Akman, Ahmet

2017-09-15

To report a case of circumferential neuroepithelial cyst of the ciliary body presenting with pigment dispersion (PD) and ocular hypertension. 48-year-old female patient presented with a complaint of pain in the left eye. On examination, visual acuity of the left eye was 0.9, and the intraocular pressure was 48 mmHg. Biomicroscopic anterior segment examination of the left eye revealed 4+ pigmented cells in the anterior chamber. Active PD from the pupillary region at 11 o'clock was noticed at the time of the examination. Ultrasound biomicroscopy demonstrated 360º cystic lesions of the ciliary body in the left eye. The patient was diagnosed as neuroepithelial cyst of the ciliary body. Our case is unique as it is the first case of circumferential neuroepithelial ciliary body cyst presenting with acute PD and ocular hypertension.

Mycotic cysts: report of 21 cases including eight pheomycotic cysts from Saudi Arabia.

PubMed

Sheikh, Salwa S; Amr, Samir S

2007-04-01

Mycotic cysts are subcutaneous cystic granulomas caused by either dematiaceous (pigmented) fungi (pheomycotic cysts) or eumycotic (nonpigmented fungi) present in soil, wood, and decaying plant material. These fungi gain access to the tissues via a wooden splinter or thorn. No deep tissue involvement or extension to bone is known to occur. We reviewed our surgical pathology files for the last 32 years. All cases with the diagnosis of cysts with fungi, thorns, or splinters and associated granulomatous and acute inflammation were reviewed. Gomori's silver and periodic acid-Schiff stains were performed in all cases. Twenty-one cases of mycotic cyst were found, including eight pheomycotic cysts (one with a recurrent lesion seen 11 months after the initial excision of the cyst). Thirteen cysts had nonpigmented fungal hyphae. There were 14 males and seven females, with an age range of 5-76 years. The dorsum of the foot was the most frequently affected site (12 cases). Four cases involved the fingers, two involved the knee area, two involved the big toe, and one each involved the leg, ankle, and forearm. The cysts measured 0.6-4.5 cm in diameter. Histologically, there was granulomatous inflammation with a variable degree of neutrophilic infiltrate giving central abscess formation. Twelve cases showed a wooden splinter. All cases were positive for fungal organisms, mostly septate hyphae and spores that were highlighted by special stains. Fungal pigment, ranging from yellow-brown to light brown to black, was observed in eight cases. No extension to deep tissues was noted. The clinical impression varied widely including ganglion, sebaceous cyst, giant cell tumor of the tendon sheath, and lipoma. One patient was immunosuppressed following renal transplantation. All patients were treated by simple excision. No antifungal chemotherapy was needed or administered in any of the patients. One patient had a recurrence of his lesion within 1 year as a result of inadequate initial excision. A second re-excision was curative. Mycotic cysts are uncommonly encountered lesions that can be easily missed, especially in cases with scant fungal elements, thus requiring special stains to detect the organisms. We reported 21 cases of mycotic cyst, including eight pheomycotic cysts, with emphasis on the histopathologic recognition of this unusual entity.

Induction of protective immunity against toxoplasmosis in mice by immunization with Toxoplasma gondii RNA.

PubMed

Dimier-Poisson, Isabelle; Aline, Fleur; Bout, Daniel; Mévélec, Marie-Noëlle

2006-03-06

Toxoplasma gondii enters the mucosal surfaces of the host, and so immunity at these sites is of major interest. Due to the compartmentalization of the immune response, systemic immunization does not induce high levels of immunity at mucosal surfaces. Intranasal immunization has been shown to be very effective in inducing both systemic and mucosal immune responses. Immunization with mRNA can induce both humoral and cell-mediated immune responses, both of which are important in conferring immunity to T. gondii. The efficacy of RNA vaccination by the nasal route with T. gondii RNA was evaluated. We assessed the percentage of cumulative survival after an oral challenge with a lethal dose of T. gondii cysts (40 cysts), and the number of brain cysts following a challenge with a sublethal dose of T. gondii 76 K cysts (15 cysts). Vaccinated mice were found to be significantly better protected than non-immunized mice after a challenge with a lethal dose of cysts; and a challenge with a sublethal dose also resulted in fewer brain cysts than in non-immunized mice. Sera and intestinal secretions of immunized mice recognized T. gondii antigens, suggesting that a specific humoral immune response may occur. Moreover, a specific lymphoproliferative response observed in cervical lymph nodes may confer protection. These preliminary findings suggest that RNA vaccination by a mucosal route could be feasible.

Types of Stem Cells

MedlinePlus

... Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

Differential expression of cyclin D1 in keratin-producing odontogenic cysts.

PubMed

Vera-Sirera, Beatriz; Forner-Navarro, Leopoldo; Vera-Sempere, Francisco

2015-01-01

The aim of the present study was to analyze the expression levels of Cyclin D1 (CCD1), a nuclear protein that plays a crucial role in cell cycle progression, in a series of keratin-producing odontogenic cysts. A total of 58 keratin-producing odontogenic cysts, diagnosed over ten years and classified according to the WHO 2005 criteria, were immunohistochemically analyzed in terms of CCD1 expression, which was quantified in the basal, suprabasal and intermediate/superficial epithelial compartments. The extent of immunostaining was measured as a proportion of total epithelial thickness. Quantified immunohistochemical data were correlated with clinicopathological features and clinical recurrence. Keratin-producing odontogenic cysts were classified as 6 syndromic keratocystic odontogenic tumors (S-KCOT), 40 sporadic or non-syndromic KCOT (NS-KCOT) and 12 orthokeratinized odontogenic cysts (OOC). Immunohistochemically, CCD1 staining was evident predominantly in the parabasal region of all cystic lesions, but among-lesion differences were apparent, showing a clear expansion of parabasal compartment especially in the S-KCOT, followed to a lesser extent in the NS-KCOT, and being much more reduced in the OOC, which had the greatest average epithelial thickness. The differential expression of CCD1 noted in the present study suggests that dysregulation of cell cycle progression from G1 to the S phase contributes to the different aggressiveness of these lesions. However, CCD1 expression levels did not predict NS-KCOT recurrence, which is likely influenced by factors unrelated to lesion biology.

Atomic force microscopic imaging of Acanthamoeba castellanii and Balamuthia mandrillaris trophozoites and cysts.

PubMed

Aqeel, Yousuf; Siddiqui, Ruqaiyyah; Ateeq, Muhammad; Raza Shah, Muhammad; Kulsoom, Huma; Khan, Naveed Ahmed

2015-01-01

Light microscopy and electron microscopy have been successfully used in the study of microbes, as well as free-living protists. Unlike light microscopy, which enables us to observe living organisms or the electron microscope which provides a two-dimensional image, atomic force microscopy provides a three-dimensional surface profile. Here, we observed two free-living amoebae, Acanthamoeba castellanii and Balamuthia mandrillaris under the phase contrast inverted microscope, transmission electron microscope and atomic force microscope. Although light microscopy was of lower magnification, it revealed functional biology of live amoebae such as motility and osmoregulation using contractile vacuoles of the trophozoite stage, but it is of limited value in defining the cyst stage. In contrast, transmission electron microscopy showed significantly greater magnification and resolution to reveal the ultra-structural features of trophozoites and cysts including intracellular organelles and cyst wall characteristics but it only produced a snapshot in time of a dead amoeba cell. Atomic force microscopy produced three-dimensional images providing detailed topographic description of shape and surface, phase imaging measuring boundary stiffness, and amplitude measurements including width, height and length of A. castellanii and B. mandrillaris trophozoites and cysts. These results demonstrate the importance of the application of various microscopic methods in the biological and structural characterization of the whole cell, ultra-structural features, as well as surface components and cytoskeleton of protist pathogens. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

miRNA-regulated cancer stem cells: understanding the property and the role of miRNA in carcinogenesis.

PubMed

Chakraborty, Chiranjib; Chin, Kok-Yong; Das, Srijit

2016-10-01

Over the last few years, microRNAs (miRNA)-controlled cancer stem cells have drawn enormous attention. Cancer stem cells are a small population of tumor cells that possess the stem cell property of self-renewal. Recent data shows that miRNA regulates this small population of stem cells. In the present review, we explained different characteristics of cancer stem cells as well as miRNA regulation of self-renewal and differentiation in cancer stem cells. We also described the migration and tumor formation. Finally, we described the different miRNAs that regulate various types of cancer stem cells, such as prostate cancer stem cells, head and neck cancer stem cells, breast cancer stem cells, colorectal cancer stem cells, lung cancer stem cells, gastric cancer stem cells, pancreatic cancer stem cells, etc. Extensive research is needed in order to employ miRNA-based therapeutics to control cancer stem cell population in various cancers in the future.

A case of dedifferentiated chondrosarcoma arising in the cricoid cartilage that mimicked an aneurysmal bone cyst.

PubMed

Chen, Lixiao; Yu, Ziwei; Jiang, Rui; Dong, Pin; Shen, Bin; Li, Yu

2018-03-01

Dedifferentiated chondrosarcoma of the larynx is a rare and highly malignant tumor. We present the report of a 59-year-old man with dedifferentiated laryngeal chondrosarcoma, which was difficult to diagnose even under microscopic examination. The original diagnosis was an aneurysmal bone cyst, and the final diagnosis was established only after careful consideration of the imaging, surgical, and microscopic findings. In clinical practice, there are many similarities between dedifferentiated chondrosarcoma and aneurysmal bone cysts. Furthermore, it is difficult to identify dedifferentiated laryngeal chondrosarcoma with a giant-cell malignant mesenchymal component. This report describes our experience and discusses this phenomenon.

What is a stem cell?

PubMed

Slack, Jonathan M W

2018-05-15

The historical roots of the stem cell concept are traced with respect to its usage in embryology and in hematology. The modern consensus definition of stem cells, comprising both pluripotent stem cells in culture and tissue-specific stem cells in vivo, is explained and explored. Methods for identifying stem cells are discussed with respect to cell surface markers, telomerase, label retention and transplantability, and properties of the stem cell niche are explored. The CreER method for identifying stem cells in vivo is explained, as is evidence in favor of a stochastic rather than an obligate asymmetric form of cell division. In conclusion, it is found that stem cells do not possess any unique and specific molecular markers; and stem cell behavior depends on the environment of the cell as well as the stem cell's intrinsic qualities. Furthermore, the stochastic mode of division implies that stem cell behavior is a property of a cell population not of an individual cell. In this sense, stem cells do not exist in isolation but only as a part of multicellular system. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Methods and Principles Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells. © 2018 Wiley Periodicals, Inc.

Effect of red cyst cell inoculation and iron(II) supplementation on autotrophic astaxanthin production by Haematococcus pluvialis under outdoor summer conditions.

PubMed

Hong, Min-Eui; Choi, Yoon Young; Sim, Sang Jun

2016-01-20

The negative effect of heat stress on the autotrophic astaxanthin production by Haematococcus pluvialis has been observed during outdoor culture in summer. Under the summer conditions, the proliferation of vegetative cells was highly halted in the green stage and the inducibility in the biosynthesis of astaxanthin was partly hindered in the red stage. Herein, under outdoor summer conditions in which variations of the diurnal temperature occur, heat-stress-driven inefficient vegetative growth of H. pluvialis was highly improved by inoculating the red cyst cells; thereby, maintaining relatively moderate intracellular carotenoid levels in the green stage. Subsequently, a remarkably enhanced astaxanthin titer was successfully obtained by supplementing 50 μM iron(II) to induce the heat stress-driven Haber-Weiss reaction in the red stage. As a result, the productivity of astaxanthin in the cells cultured under summer temperature conditions (23.4-33.5 °C) using the two methods of red cell (cyst) inoculation and the iron(Fe(2+)) supplementation was increased by 147% up to 5.53 mg/L day compared with that of the cells cultured under spring temperature conditions (17.5-27.3 °C). Our technical solutions will definitely improve the annual natural astaxanthin productivity in H. pluvialis in locations confronted by hot summer weather, particularly in large-scale closed photobioreactor systems. Copyright © 2015 Elsevier B.V. All rights reserved.

Acanthamoebicidal activity of periglaucine A and betulinic acid from Pericampylus glaucus (Lam.) Merr. in vitro.

PubMed

Mahboob, Tooba; Azlan, Abdul-Majid; Shipton, Fiona Natalia; Boonroumkaew, Patcharaporn; Nor Azman, Nadiah Syafiqah; Sekaran, Shamala Devi; Ithoi, Init; Tan, Tian-Chye; Samudi, Chandramathi; Wiart, Christophe; Nissapatorn, Veeranoot

2017-12-01

Acanthamoeba species are pathogenic protozoa which account for amoebic keratitis, conjunctivitis and granulomatous amoebic encephalitis. These amoebae form cysts which resist drugs and more effective acanthamoebicidal agents are needed. Medicinal plants could be useful in improving the current treatment strategies for Acanthamoeba infections. In the present study, we examined the amoebicidal effects of Pericampylus glaucus (Lam.) Merr., a medicinal plant used for the treatment of conjunctivitis in Malaysia. Pathogenic Acanthamoeba triangularis were isolated from environmental water samples and treated with different concentrations of fractions obtained from Pericampylus glaucus (Lam.) Merr. as well as main constituents for 24-72 h. Chlorhexidine was used as a reference drug. Ethanol fraction of stem showed significant (p < 0.05) inhibition of trophozoites survival. Betulinic acid and periglaucine A from this plant at 100 μg/mL inhibited more than 70% survival of both cysts and trophozoites. The calculated therapeutic index for betulinic acid and periglaucine A was 170 and 1.5 for trophozoites stage and 3.75 and 8.5 for cysts stage. The observed amoebicidal efficacies indicate the beneficial aspects of this plant in the treatment of Acanthamoeba infection. Periglaucine A could also be of value for the treatment of Acanthamoeba infection. Copyright © 2017 Elsevier Inc. All rights reserved.

A Telomerase Immortalized Human Proximal Tubule Cell Line with a Truncation Mutation (Q4004X) in Polycystin-1

PubMed Central

Herbert, Brittney-Shea; Grimes, Brenda R.; Xu, Wei Min; Werner, Michael; Ward, Christopher; Rossetti, Sandro; Harris, Peter; Bello-Reuss, Elsa; Ward, Heather H.; Miller, Caroline; Gattone, Vincent H.; Phillips, Carrie L.; Wandinger-Ness, Angela; Bacallao, Robert L.

2013-01-01

Autosomal dominant polycystic kidney disease (ADPKD) is associated with a variety of cellular phenotypes in renal epithelial cells. Cystic epithelia are secretory as opposed to absorptive, have higher proliferation rates in cell culture and have some characteristics of epithelial to mesenchymal transitions [1], [2]. In this communication we describe a telomerase immortalized cell line that expresses proximal tubule markers and is derived from renal cysts of an ADPKD kidney. These cells have a single detectable truncating mutation (Q4004X) in polycystin-1. These cells make normal appearing but shorter cilia and fail to assemble polycystin-1 in the cilia, and less uncleaved polycystin-1 in membrane fractions. This cell line has been maintained in continuous passage for over 35 passages without going into senescence. Nephron segment specific markers suggest a proximal tubule origin for these cells and the cell line will be useful to study mechanistic details of cyst formation in proximal tubule cells. PMID:23383103

Near-bottom circulation and dispersion of sediment containing Alexandrium fundyense cysts in the Gulf of Maine during 2010-2011

USGS Publications Warehouse

Aretxabaleta, Alfredo L.; Butman, Bradford; Signell, Richard P.; Dalyander, P. Soupy; Sherwood, Christopher R.; Sheremet, Vitalii A.; McGillicuddy, Dennis J.

2014-01-01

The life cycle of Alexandrium fundyense in the Gulf of Maine includes a dormant cyst stage that spends the winter predominantly in the bottom sediment. Wave-current bottom stress caused by storms and tides induces resuspension of cyst-containing sediment during winter and spring. Resuspended sediment could be transported by water flow to different locations in the Gulf and the redistribution of sediment containing A. fundyense cysts could alter the spatial and temporal manifestation of its spring bloom. The present study evaluates model near-bottom flow during storms, when sediment resuspension and redistribution are most likely to occur, between October and May when A. fundyense cells are predominantly in cyst form. Simulated water column sediment (mud) concentrations from representative locations of the Gulf are used to initialize particle tracking simulations for the period October 2010–May 2011. Particles are tracked in full three-dimensional model solutions including a sinking velocity characteristic of cyst and aggregated mud settling (0.1 mm s−1). Although most of the material was redeposited near the source areas, small percentages of total resuspended sediment from some locations in the western (~4%) and eastern (2%) Maine shelf and the Bay of Fundy (1%) traveled distances longer than 100 km before resettling. The redistribution changed seasonally and was sensitive to the prescribed sinking rate. Estimates of the amount of cysts redistributed with the sediment were small compared to the inventory of cysts in the upper few centimeters of sediment but could potentially have more relevance immediately after deposition.

Literature Review of Periclitoral Cysts in the Prepubertal Population.

PubMed

Nelson, Kayla L; McQuillan, Sarah K; Brain, Philippa

2016-12-01

Clitoral cysts in the pediatric population are rare conditions that require careful evaluation. In this review of the literature we discuss the evaluation of clitoral abnormalities in the pediatric population, the development of clitoral cysts, and how to differentiate benign from malignant tumors. In addition, a summary of relevant cases of clitoral tumors in the literature are discussed. Literature review. A MedLine and advanced PubMed search was conducted of all English language articles published using the search terms "clitoris" and "cyst" until February 2015. Reference tracing was completed for all articles for completeness. Literature review of clitoral cysts in the prepubertal population. In total, we found 15 cases of benign, spontaneously forming clitoral cysts reported. Eleven of those cases document symptom onset before puberty. Reports of other benign clitoral lesions in the pediatric population include 1 angiokeratoma, 1 hemangiopericytoma, 1 granular cell tumor, 6 hemangiomas, and approximately 30 neurofibromas. Clitoral malignancies in the pediatric population are even more rare with only 3 cases of clitoral schwannomas, 2 rhabdomyosarcomas, 1 lymphoma, and 1 endodermal sinus tumor documented in the literature. Clitoral cysts must be considered as a possible cause of clitoral enlargement in the prepubertal population. Clitoral tumors are distinguished clinically from hormonal abnormalities and intersex disorders by their hormonal profile, and the presence of an underlying mass. Ultrasound and magnetic resonance imaging might be useful imaging modalities to further characterize the clitoral enlargement. When confirmed as the most likely diagnosis, surgical resection is the mainstay of treatment for clitoral cysts. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Proteomic Study of Entamoeba histolytica Trophozoites, Cysts, and Cyst-Like Structures

PubMed Central

Luna-Nácar, Milka; Navarrete-Perea, José; Moguel, Bárbara; Bobes, Raúl J.; Laclette, Juan P.; Carrero, Julio C.

2016-01-01

The cyst stage of Entamoeba histolytica is a promising therapeutic target against human amoebiasis. Our research team previously reported the production in vitro of Cyst-Like Structures (CLS) sharing structural features with cysts, including rounded shape, size reduction, multinucleation, and the formation of a chitin wall coupled to the overexpression of glucosamine 6-phosphate isomerase, the rate-limiting enzyme of the chitin synthesis pathway. A proteomic study of E. histolytica trophozoites, cysts, and in vitro-produced CLS is reported herein to determine the nature of CLS, widen our knowledge on the cyst stage, and identify possible proteins and pathways involved in the encystment process. Total protein extracts were obtained from E. histolytica trophozoites, CLS, and partially purified cysts recovered from the feces of amoebic human patients; extracts were trypsin-digested and analyzed by LC-MS/MS. In total, 1029 proteins were identified in trophozoites, 550 in CLS, and 411 in cysts, with 539, 299, and 84 proteins unique to each sample, respectively, and only 74 proteins shared by all three stages. About 70% of CLS proteins were shared with trophozoites, even though differences were observed in the relative protein abundance. While trophozoites showed a greater abundance of proteins associated to a metabolically active cell, CLS showed higher expression of proteins related to proteolysis, redox homeostasis, and stress response. In addition, the expression of genes encoding for the cyst wall proteins Jessie and Jacob was detected by RT-PCR and the Jacob protein identified by Western blotting and immunofluorescence in CLS. However, the proteomic profile of cysts as determined by LC-MS/MS was very dissimilar to that of trophozoites and CLS, with almost 40% of hypothetical proteins. Our global results suggest that CLS are more alike to trophozoites than to cysts, and they could be generated as a rapid survival response of trophozoites to a stressful condition, which allows the parasite to survive temporarily inside a chitin-like resistant cover containing Jacob protein. Our findings lead us to suggest that encystment and CLS formation could be distinct stress responses. In addition, we show that cysts express a high number of genes with unknown function, including four new, highly antigenic, possibly membrane-located proteins that could be targets of therapeutic and diagnostic usefulness. PMID:27228164

Cysteine proteases and cell differentiation: excystment of the ciliated protist Sterkiella histriomuscorum.

PubMed

Villalobo, Eduardo; Moch, Clara; Fryd-Versavel, Ghislaine; Fleury-Aubusson, Anne; Morin, Loïc

2003-12-01

The process of excystment of Sterkiella histriomuscorum (Ciliophora, Oxytrichidae) leads in a few hours, through a massive influx of water and the resorption of the cyst wall, from an undifferentiated resting cyst to a highly differentiated and dividing vegetative cell. While studying the nature of the genes involved in this process, we isolated three different cysteine proteases genes, namely, a cathepsin B gene, a cathepsin L-like gene, and a calpain-like gene. Excystation was selectively inhibited at a precise differentiating stage by cysteine proteases inhibitors, suggesting that these proteins are specifically required during the excystment process. Reverse transcription-PCR experiments showed that both genes display differential expression between the cyst and the vegetative cells. A phylogenetic analysis showed for the first time that the cathepsin B tree is paraphyletic and that the diverging S. histriomuscorum cathepsin B is closely related to its Giardia homologues, which take part in the cyst wall breakdown process. The deduced cathepsin L-like protein sequence displays the structural signatures and phylogenetic relationships of cathepsin H, a protein that is known only in plants and animals and that is involved in the degradation of extracellular matrix components in cancer diseases. The deduced calpain-like protein sequence does not display the calcium-binding domain of conventional calpains; it belongs to a diverging phylogenetic cluster that includes Aspergillus palB, a protein which is involved in a signal transduction pathway that is sensitive to ambient pH.

Reciprocal expression of integration host factor and HU in the developmental cycle and infectivity of Legionella pneumophila.

PubMed

Morash, Michael G; Brassinga, Ann Karen C; Warthan, Michelle; Gourabathini, Poornima; Garduño, Rafael A; Goodman, Steven D; Hoffman, Paul S

2009-04-01

Legionella pneumophila is an intracellular parasite of protozoa that differentiates late in infection into metabolically dormant cysts that are highly infectious. Regulation of this process is poorly understood. Here we report that the small DNA binding regulatory proteins integration host factor (IHF) and HU are reciprocally expressed over the developmental cycle, with HU expressed during exponential phase and IHF expressed postexponentially. To assess the role of these regulatory proteins in development, chromosomal deletions were constructed. Single (ihfA or ihfB) and double deletion (Deltaihf) IHF mutants failed to grow in Acanthamoeba castellanii unless complemented in trans when expressed temporally from the ihfA promoter but not under P(tac) (isopropyl-beta-d-thiogalactopyranoside). In contrast, IHF mutants were infectious for HeLa cells, though electron microscopic examination revealed defects in late-stage cyst morphogenesis (thickened cell wall, intracytoplasmic membranes, and inclusions of poly-beta-hydroxybutyrate), and were depressed for the developmental marker MagA. Green fluorescent protein promoter fusion assays indicated that IHF and the stationary-phase sigma factor RpoS were required for full postexponential expression of magA. Finally, defects in cyst morphogenesis noted for Deltaihf mutants in HeLa cells correlated with a loss of both detergent resistance and hyperinfectivity compared with results for wild-type cysts. These studies establish IHF and HU as markers of developmental stages and show that IHF function is required for both differentiation and full virulence of L. pneumophila in natural amoebic hosts.

Multiple non-syndromic odontogenic keratocysts in three siblings

PubMed Central

Nirwan, Amit; Wanjari, Sangeeta Panjab; Saikhedkar, Rashmi; Karun, Vinayak

2013-01-01

Occurrence of multiple cysts (MC) involving the jaw is rare. When multiple, it is usually associated with a syndrome. Occurrence of MC without syndromic association is extremely rare. Multiple odontogenic cysts mostly could be odontogenic keratocysts or dentigerous cysts. Odontogenic keratocyst shows involvement of mandible over maxilla, with peak incidence in second and third decade and it is exceedingly rare before 10 years of age. However multiple odontogenic keratocysts found in children are often reflective of nevoid basal cell carcinoma syndrome. Here is a case report which documents multiple jaw cysts involving both the jaws, in three siblings of ages 10, 13 and 17 years with negative parental history. All three reported cases were free of any systemic involvement. As odontogenic keratocyst spreads through bone marrow, destruction is more before any clinical manifestation. Therefore, early detection and intervention are essential in preventing extensive destruction. PMID:23505078

Differential marker expression by cultures rich in mesenchymal stem cells

PubMed Central

2013-01-01

Background Mesenchymal stem cells have properties that make them amenable to therapeutic use. However, the acceptance of mesenchymal stem cells in clinical practice requires standardized techniques for their specific isolation. To date, there are no conclusive marker (s) for the exclusive isolation of mesenchymal stem cells. Our aim was to identify markers differentially expressed between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. We compared and contrasted the phenotype of tissue cultures in which mesenchymal stem cells are rich and rare. By initially assessing mesenchymal stem cell differentiation, we established that bone marrow and breast adipose cultures are rich in mesenchymal stem cells while, in our hands, foreskin fibroblast and olfactory tissue cultures contain rare mesenchymal stem cells. In particular, olfactory tissue cells represent non-stem cell mesenchymal cells. Subsequently, the phenotype of the tissue cultures were thoroughly assessed using immuno-fluorescence, flow-cytometry, proteomics, antibody arrays and qPCR. Results Our analysis revealed that all tissue cultures, regardless of differentiation potential, demonstrated remarkably similar phenotypes. Importantly, it was also observed that common mesenchymal stem cell markers, and fibroblast-associated markers, do not discriminate between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. Examination and comparison of the phenotypes of mesenchymal stem cell and non-stem cell mesenchymal cell cultures revealed three differentially expressed markers – CD24, CD108 and CD40. Conclusion We indicate the importance of establishing differential marker expression between mesenchymal stem cells and non-stem cell mesenchymal cells in order to determine stem cell specific markers. PMID:24304471

Zebrafish mutations affecting cilia motility share similar cystic phenotypes and suggest a mechanism of cyst formation that differs from pkd2 morphants

PubMed Central

Sullivan-Brown, Jessica; Schottenfeld, Jodi; Okabe, Noriko; Hostetter, Christine L.; Serluca, Fabrizio C.; Thiberge, Stephan Y.; Burdine, Rebecca D.

2008-01-01

Zebrafish are an attractive model for studying the earliest cellular defects occurring during renal cyst formation because its kidney (the pronephros) is simple and genes that cause cystic kidney diseases (CKD) in humans, cause pronephric dilations in zebrafish. By comparing phenotypes in three different mutants, locke, swt and kurly, we find that dilations occur prior to 48 hpf in the medial tubules, a location similar to where cysts form in some mammalian diseases. We demonstrate that the first observeable phenotypes associated with dilation include cilia motility and luminal remodeling defects. Importantly, we show that some phenotypes common to human CKD, such as an increased number of cells, are secondary consequences of dilation. Despite having differences in cilia motility, locke, swt and kurly share similar cystic phenotypes, suggesting that they function in a common pathway. To begin to understand the molecular mechanisms involved in cyst formation, we have cloned the swt mutation and find that it encodes a novel leucine rich repeat containing protein (LRRC50), which is thought to function in correct dynein assembly in cilia. Finally, we show that knockdown of polycystic kidney disease 2 (pkd2) specifically causes glomerular cysts and does not affect cilia motility, suggesting multiple mechanisms exist for cyst formation. PMID:18178183

Germline Proliferation Is Regulated by Somatic Endocytic Genes via JNK and BMP Signaling in Drosophila.

PubMed

Tang, Yaning; Geng, Qing; Chen, Di; Zhao, Shaowei; Liu, Xian; Wang, Zhaohui

2017-05-01

Signals derived from the microenvironment contribute greatly to tumorigenesis . The underlying mechanism requires thorough investigation. Here, we use Drosophila testis as a model system to address this question, taking the advantage of the ease to distinguish germline and somatic cells and to track the cell numbers. In an EMS mutagenesis screen, we identified Rab5 , a key factor in endocytosis, for its nonautonomous role in germline proliferation. The disruption of Rab5 in somatic cyst cells, which escort the development of germline lineage, induced the overproliferation of underdifferentiated but genetically wild-type germ cells. We demonstrated that this nonautonomous effect was mediated by the transcriptional activation of Dpp [the fly homolog of bone morphogenetic protein (BMP)] by examining the Dpp-reporter expression and knocking down Dpp to block germline overgrowth. Consistently, the protein levels of Bam, the germline prodifferentiation factor normally accumulated in the absence of BMP/Dpp signaling, decreased in the overproliferating germ cells. Further, we discovered that the JNK signaling pathway operated between Rab5 and Dpp, because simultaneously inhibiting the JNK pathway and Rab5 in cyst cells prevented both dpp transcription and germline tumor growth. Additionally, we found that multiple endocytic genes, such as avl , TSG101 , Vps25 , or Cdc42 , were required in the somatic cyst cells to restrict germline amplification. These findings indicate that when the endocytic state of the surrounding cells is impaired, genetically wild-type germ cells overgrow. This nonautonomous model of tumorigenesis provides a simple system to dissect the relation between tumor and its niche. Copyright © 2017 by the Genetics Society of America.

The Structure of the Statocyst of the Freshwater Snail Biomphalaria Glabrata (Pulmonata, Basommatophora)

NASA Technical Reports Server (NTRS)

Gao, Wenyuan; Wiederhold, Michael L.

1997-01-01

The structure of the statocyst of the freshwater snail Biomphalaria glabrata has been examined by light and electron microscopy. The two statocysts are located on the dorsal-lateral side of the left and right pedal ganglion. The statocysts are spherical, fluid-filled capsules with a diameter of approximately 60 microns for young and 110 microns for adult snails. The wall of the cyst is composed of large receptor cells and many smaller supporting cells. The receptor cells bear cilia which are evenly distributed on the apical surface. The cilia have the typical 9+2 internal tubule configuration. Striate rootlets originate from the base of the basal body and run downward into the cytoplasm. Side-roots arise from one side of the basal body and a basal foot from the other. For each receptor cell, the basal foot always points to the periphery of the surface, indicating that the receptor cell is non-polarized. The receptor cells contain cytoplasmic organelles such as mitochondria, ribosomes, rough and smooth endoplasmic reticulum, compact Golgi bodies and multivesicular bodies. Supporting cells bearing microvilli are interposed between the receptor cells. The junction complex between the supporting cells and the receptor cells is composed of adherens and septate junctions, while between supporting cells only the adherens junctions are present. The static nerve arises from the lateral side of the cyst and contains axons in which parallel neurotubules and mitochondria are found. The axons arise directly from the base of the receptor cells without synapse. In the cyst lumen there are unattached statoconia. The statoconia have a plate-like or concentric membranous ring structure. Based on the morphology, the function of the statocyst in Biomphalaria is discussed.

Canine ovarian neoplasms: a clinicopathologic study of 71 cases, including histology of 12 granulosa cell tumors.

PubMed

Patnaik, A K; Greenlee, P G

1987-11-01

In a retrospective study of 71 primary ovarian tumors in the dog, epithelial tumors (46%) were more common than sex cord stromal (34%) and germ cell tumors (20%). There were more adenocarcinomas (64%) than adenomas. Sex cord stromal tumors were equally divided into Sertoli-Leydig (12/24) and granulosa cell tumors (12/24). There were equal numbers (7/14) of dysgerminomas and teratomas among the germ cell tumors. Most teratomas (6/7) were malignant. Most granulosa cell tumors were solid; two were mostly cystic. Patterns included sheets of round and ovoid to spindle-shaped cells separated by thin, fibrovascular stroma; neoplastic cells formed rosettes or Call-Exner bodies. In some areas, neoplastic cells were in cords or columns and formed cyst-like structures. Four granulosa cell tumors were macrofollicular, having cysts lined with granulosa cells. Median ages of dogs with different ovarian neoplasms were similar; all were more than 10 years old, except the dogs with teratoma (mean age, 4 years). Most neoplasms were unilateral (84%), except the Sertoli-Leydig cell tumors, many of which were bilateral (36%). Size of ovarian neoplasms varied (2 cm3 to 15,000 cm3). Twenty-nine percent of neoplasms metastasized; adenocarcinomas (48%) and malignant teratomas (50%) had the highest rates, and distant metastasis was more common in malignant teratoma. Endometrial hyperplasia was in 67% of the dogs; it was most common in dogs with sex cord stromal tumors (95%). Uterine malignancy was not seen in dogs with granulosa cell tumors, although hyperplasia endometrium was in all dogs with this tumor. Cysts in the contralateral ovaries were most common in dogs with sex cord stromal tumors.

Learn About Stem Cells

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Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin.

PubMed

Dorn, Isabel; Klich, Katharina; Arauzo-Bravo, Marcos J; Radstaak, Martina; Santourlidis, Simeon; Ghanjati, Foued; Radke, Teja F; Psathaki, Olympia E; Hargus, Gunnar; Kramer, Jan; Einhaus, Martin; Kim, Jeong Beom; Kögler, Gesine; Wernet, Peter; Schöler, Hans R; Schlenke, Peter; Zaehres, Holm

2015-01-01

Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex vivo expansion of induced pluripotent stem cells into erythroid cells, we compared induced pluripotent stem cells from human neural stem cells and human cord blood-derived CD34(+) hematopoietic stem cells and evaluated their potential for differentiation into hematopoietic progenitor and mature red blood cells. Although genome-wide DNA methylation profiling at all promoter regions demonstrates that the epigenetic memory of induced pluripotent stem cells is influenced by the somatic cell type of origin of the stem cells, we found a similar hematopoietic induction potential and erythroid differentiation pattern of induced pluripotent stem cells of different somatic cell origin. All human induced pluripotent stem cell lines showed terminal maturation into normoblasts and enucleated reticulocytes, producing predominantly fetal hemoglobin. Differences were only observed in the growth rate of erythroid cells, which was slightly higher in the induced pluripotent stem cells derived from CD34(+) hematopoietic stem cells. More detailed methylation analysis of the hematopoietic and erythroid promoters identified similar CpG methylation levels in the induced pluripotent stem cell lines derived from CD34(+) cells and those derived from neural stem cells, which confirms their comparable erythroid differentiation potential. Copyright© Ferrata Storti Foundation.

[Progress in stem cells and regenerative medicine].

PubMed

Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

2015-06-01

Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

Application of Graphene Based Nanotechnology in Stem Cells Research.

PubMed

Hu, Shanshan; Zeng, Yongxiang; Yang, Shuying; Qin, Han; Cai, He; Wang, Jian

2015-09-01

The past several years have witnessed significant advances in stem cell therapy, tissue engineering and regenerative medicine. Graphene, with its unique properties such as high electrical conductivity, elasticity and good molecule absorption, have potential for creating the next generation of biomaterials. This review summarizes the interrelationship between graphene and stem cells. The analysis of graphene when applied on mesenchymal stem cells, neural stem cells, induced pluripotent stem cells, embryonic stem cells, periodontal ligament stem cells, human adipose-derived stem cells and cancer stem cells, and how graphene influences cell behavior and differentiation are discussed in details.

A revisionist history of adult marrow stem cell biology or 'they forgot about the discard'.

PubMed

Quesenberry, P; Goldberg, L

2017-08-01

The adult marrow hematopoietic stem cell biology has largely been based on studies of highly purified stem cells. This is unfortunate because during the stem cell purification the great bulk of stem cells are discarded. These cells are actively proliferating. The final purified stem cell is dormant and not representative of the whole stem cell compartment. Thus, a large number of studies on the cellular characteristics, regulators and molecular details of stem cells have been carried on out of non-represented cells. Niche studies have largely pursued using these purified stem cells and these are largely un-interpretable. Other considerations include the distinction between baseline and transplant stem cells and the modulation of stem cell phenotype by extracellular vesicles, to cite a non-inclusive list. Work needs to proceed on characterizing the true stem cell population.

Multiloculated solitary (unicameral) bone cyst in a young dog.

PubMed

Roode, Sarah C; Shive, Heather R; Hoorntje, Willemijn; Bernard, Jennifer; Stowe, Devorah M; Pool, Roy R; Grindem, Carol B

2018-05-21

A 20-month-old female spayed Staffordshire Terrier (22.3 kg) presented to the Orthopedic Surgery Service at North Carolina State University Veterinary Teaching Hospital for evaluation of a 6-week history of toe-touching to nonweight-bearing lameness in the right hind limb. Radiographs of the right stifle revealed a multiloculated lytic lesion of the distal femur, with a large open lytic zone centrally, numerous osseous septations peripherally, and focal areas of cortical thinning and loss. An aspirate of the right distal femoral lesion yielded mildly cloudy serosanguineous fluid. Cytologic examination of the fluid revealed a pleomorphic population of discrete cells that exhibited marked anisocytosis and anisokaryosis and a variable nucleus to cytoplasm (N:C) ratio, which were interpreted as probable neoplastic cells, with few macrophages, and evidence of hemorrhage. Given the clinical signs of pain, lesion size, and concern for malignant neoplasia, amputation of the right hind limb was performed. Histologically, the lesion had undulating walls 1-3 mm thick with a continuous outer layer of dense fibrous tissue and an inner layer composed of reactive cancellous bone with no cortical compacta remaining. Remnants of thin fibrous or fibro-osseous septa projected from the bony wall into the cyst lumen. The final histologic diagnosis was a benign multiloculated solitary (unicameral) bone cyst of the distal right femur. Based on the histopathologic findings, it was speculated that the cells identified on cytology were a mixture of developing osteoclasts, osteoblasts, endothelial, and stromal cells. This is the first report describing the cytologic examination of a solitary bone cyst in veterinary medicine. © 2018 American Society for Veterinary Clinical Pathology.

Comparison of titanium elastic intramedullary nailing versus injection of bone marrow in treatment of simple bone cysts in children: a retrospective study.

PubMed

Li, Wenchao; Xu, Ruijiang; Du, Minghua; Chen, Hui

2016-08-15

Simple bone cysts are common benign lytic bone lesions in children. The main goals of treatment for bone cysts are to prevent pathological fractures, support the healing process, and prevent recurrence. This retrospective study compared fixation with titanium elastic intramedullary nailing (TEN) versus aspiration and injection of autogenous bone marrow (ABM) for the treatment of simple bone cysts in children. Forty-six patients (mean follow-up, 62 months; range, 34-71 months) who presented with bone cysts (30 in the humerus, 16 in the femur) from January 2006 to December 2012 were retrospectively evaluated. Patients were treated with either TEN or ABM injection. Radiographs were evaluated according to previously established criteria. Clinical evaluations of pain, infection, additional fractures, and range of motion were performed. After treatment, all patients were pain-free and had normal range of motion in adjacent joints. In the ABM group, 14 (60.9 %) bone cysts completely healed, six (26.1 %) healed with small residuals after two injections, and three (13.0 %) recurred. In the TEN group, 16 (69.6 %) bone cysts completely healed, four (17.4 %) healed with small residuals, and three (13.0 %) recurred. There were no significant differences in radiographic outcomes between groups at the final follow-up (P > 0.05). Three patients developed skin irritation as a result of the nail ends. Additional fractures occurred in four patients who underwent ABM injection and in two patients who underwent TEN. No significant associations were found between pathological fractures and cyst activity, location, or treatment outcomes in the patients studied. Both TEN and ABM injection are safe and effective treatment for bone cysts. ABM injection promotes osteogenic differentiation of bone marrow stromal cells; multiple injections can reduce the likelihood of recurrence. TEN stabilizes the affected bone and thus allows early limb mobilization. It also reduces pressure in the capsule wall by continuous decompression to promote cyst healing. ABM injections can be used to treat cyst recurrence after previous TEN, with favorable results.

Inflammation and Fibrosis in Polycystic Kidney Disease.

PubMed

Song, Cheng Jack; Zimmerman, Kurt A; Henke, Scott J; Yoder, Bradley K

Polycystic kidney disease (PKD) is a commonly inherited disorder characterized by cyst formation and fibrosis (Wilson, N Engl J Med 350:151-164, 2004) and is caused by mutations in cilia or cilia-related proteins, such as polycystin 1 or 2 (Oh and Katsanis, Development 139:443-448, 2012; Kotsis et al., Nephrol Dial Transplant 28:518-526, 2013). A major pathological feature of PKD is the development of interstitial inflammation and fibrosis with an associated accumulation of inflammatory cells (Grantham, N Engl J Med 359:1477-1485, 2008; Zeier et al., Kidney Int 42:1259-1265, 1992; Ibrahim, Sci World J 7:1757-1767, 2007). It is unclear whether inflammation is a driving force for cyst formation or a consequence of the pathology (Ta et al., Nephrology 18:317-330, 2013) as in some murine models cysts are present prior to the increase in inflammatory cells (Phillips et al., Kidney Blood Press Res 30:129-144, 2007; Takahashi et al., J Am Soc Nephrol JASN 1:980-989, 1991), while in other models the increase in inflammatory cells is present prior to or coincident with cyst initiation (Cowley et al., Kidney Int 43:522-534, 1993, Kidney Int 60:2087-2096, 2001). Additional support for inflammation as an important contributor to cystic kidney disease is the increased expression of many pro-inflammatory cytokines in murine models and human patients with cystic kidney disease (Karihaloo et al., J Am Soc Nephrol JASN 22:1809-1814, 2011; Swenson-Fields et al., Kidney Int, 2013; Li et al., Nat Med 14:863-868, 2008a). Based on these data, an emerging model in the field is that disruption of primary cilia on tubule epithelial cells leads to abnormal cytokine cross talk between the epithelium and the inflammatory cells contributing to cyst growth and fibrosis (Ta et al., Nephrology 18:317-330, 2013). These cytokines are produced by interstitial fibroblasts, inflammatory cells, and tubule epithelial cells and activate multiple pathways including the JAK-STAT and NF-κB signaling (Qin et al., J Am Soc Nephrol JASN 23:1309-1318, 2012; Park et al., Am J Nephrol 32:169-178, 2010; Bhunia et al., Cell 109:157-168, 2002). Indeed, inflammatory cells are responsible for producing several of the pro-fibrotic growth factors observed in PKD patients with fibrosis (Nakamura et al., Am J Nephrol 20:32-36, 2000; Wilson et al., J Cell Physiol 150:360-369, 1992; Song et al., Hum Mol Genet 18:2328-2343, 2009; Schieren et al., Nephrol Dial Transplant 21:1816-1824, 2006). These growth factors trigger epithelial cell proliferation and myofibroblast activation that stimulate the production of extracellular matrix (ECM) genes including collagen types 1 and 3 and fibronectin, leading to reduced glomerular function with approximately 50% of ADPKD patients progressing to end-stage renal disease (ESRD). Therefore, treatments designed to reduce inflammation and slow the rate of fibrosis are becoming important targets that hold promise to improve patient life span and quality of life. In fact, recent studies in several PKD mouse models indicate that depletion of macrophages reduces cyst severity. In this chapter, we review the potential mechanisms of interstitial inflammation in PKD with a focus on ADPKD and discuss the role of interstitial inflammation in progression to fibrosis and ESRD.

Alexandrium fundyense cysts in the Gulf of Maine: long-term time series of abundance and distribution, and linkages to past and future blooms

USGS Publications Warehouse

Anderson, Donald M.; Keafer, Bruce A.; Kleindinst, Judith L.; McGillicuddy, Dennis J.; Martin, Jennifer L.; Norton, Kerry; Pilskaln, Cynthia H.; Smith, Juliette L.; Sherwood, Christopher R.; Butman, Bradford

2014-01-01

Here we document Alexandrium fundyense cyst abundance and distribution patterns over nine years (1997 and 2004–2011) in the coastal waters of the Gulf of Maine (GOM) and identify linkages between those patterns and several metrics of the severity or magnitude of blooms occurring before and after each autumn cyst survey. We also explore the relative utility of two measures of cyst abundance and demonstrate that GOM cyst counts can be normalized to sediment volume, revealing meaningful patterns equivalent to those determined with dry weight normalization. Cyst concentrations were highly variable spatially. Two distinct seedbeds (defined here as accumulation zones with>300 cysts cm−3) are evident, one in the Bay of Fundy (BOF) and one in mid-coast Maine. Overall, seedbed locations remained relatively constant through time, but their area varied 3–4 fold, and total cyst abundance more than 10 fold among years. A major expansion of the mid-coast Maine seedbed occurred in 2009 following an unusually intense A. fundyense bloom with visible red-water conditions, but that feature disappeared by late 2010. The regional system thus has only two seedbeds with the bathymetry, sediment characteristics, currents, biology, and environmental conditions necessary to persist for decades or longer. Strong positive correlations were confirmed between the abundance of cysts in both the 0–1 and the 0–3 cm layers of sediments in autumn and geographic measures of the extent of the bloom that occurred the next year (i.e., cysts→blooms), such as the length of coastline closed due to shellfish toxicity or the southernmost latitude of shellfish closures. In general, these metrics of bloom geographic extent did not correlate with the number of cysts in sediments following the blooms (blooms→cysts). There are, however, significant positive correlations between 0–3 cm cyst abundances and metrics of the preceding bloom that are indicative of bloom intensity or vegetative cell abundance (e.g., cumulative shellfish toxicity, duration of detectable toxicity in shellfish, and bloom termination date). These data suggest that it may be possible to use cyst abundance to empirically forecast the geographic extent of the forthcoming bloom and, conversely, to use other metrics from bloom and toxicity events to forecast the size of the subsequent cyst population as the inoculum for the next year's bloom. This is an important step towards understanding the excystment/encystment cycle in A. fundyense bloom dynamics while also augmenting our predictive capability for this HAB-forming species in the GOM.

Identification of Giardia lamblia DHHC Proteins and the Role of Protein S-palmitoylation in the Encystation Process

PubMed Central

Merino, María C.; Zamponi, Nahuel; Vranych, Cecilia V.; Touz, María C.; Rópolo, Andrea S.

2014-01-01

Protein S-palmitoylation, a hydrophobic post-translational modification, is performed by protein acyltransferases that have a common DHHC Cys-rich domain (DHHC proteins), and provides a regulatory switch for protein membrane association. In this work, we analyzed the presence of DHHC proteins in the protozoa parasite Giardia lamblia and the function of the reversible S-palmitoylation of proteins during parasite differentiation into cyst. Two specific events were observed: encysting cells displayed a larger amount of palmitoylated proteins, and parasites treated with palmitoylation inhibitors produced a reduced number of mature cysts. With bioinformatics tools, we found nine DHHC proteins, potential protein acyltransferases, in the Giardia proteome. These proteins displayed a conserved structure when compared to different organisms and are distributed in different monophyletic clades. Although all Giardia DHHC proteins were found to be present in trophozoites and encysting cells, these proteins showed a different intracellular localization in trophozoites and seemed to be differently involved in the encystation process when they were overexpressed. dhhc transgenic parasites showed a different pattern of cyst wall protein expression and yielded different amounts of mature cysts when they were induced to encyst. Our findings disclosed some important issues regarding the role of DHHC proteins and palmitoylation during Giardia encystation. PMID:25058047

Perspectives on stem cell therapy for cardiac regeneration. Advances and challenges.

PubMed

Choi, Sung Hyun; Jung, Seok Yun; Kwon, Sang-Mo; Baek, Sang Hong

2012-01-01

Ischemic heart disease (IHD) accelerates cardiomyocyte loss, but the developing stem cell research could be useful for regenerating a variety of tissue cells, including cardiomyocytes. Diverse sources of stem cells for IHD have been reported, including embryonic stem cells, induced pluripotent stem cells, skeletal myoblasts, bone marrow-derived stem cells, mesenchymal stem cells, and cardiac stem cells. However, stem cells have unique advantages and disadvantages for cardiac tissue regeneration, which are important considerations in determining the specific cells for improving cell survival and long-term engraftment after transplantation. Additionally, the dosage and administration method of stem cells need to be standardized to increase stability and efficacy for clinical applications. Accordingly, this review presents a summary of the stem cell therapies that have been studied for cardiac regeneration thus far, and discusses the direction of future cardiac regeneration research for stem cells.

Immunohistochemical evaluation of myofibroblast density in odontogenic cysts and tumors.

PubMed

Kouhsoltani, Maryam; Halimi, Monireh; Jabbari, Golchin

2016-01-01

Background. The aim of this study was to investigate myofibroblast (MF) density in a broad spectrum of odontogenic cysts and tumors and the relation between the density of MFs and the clinical behavior of these lesions. Methods. A total of 105 cases of odontogenic lesions, including unicystic ameloblastoma (UAM), solid ameloblastoma (SA), odontogenic keratocyst (OKC), dentigerous cyst (DC), radicular cyst (RC) (15 for each category), and odontogenic myxoma (OM), adenomatoid odontogenic tumor (AOT), calcifying odontogenic cyst (COC) (10 for each category), were immunohistochemically stained with anti-α-smooth muscle actin antibody. The mean percentage of positive cells in 10 high-power fields was considered as MF density for each case. Results. A statistically significant difference was observed in the mean scores between the study groups (P < 0.001). The intensity of MFs was significantly higher in odontogenic tumors compared to odontogenic cysts (P < 0.001). There was no statistically significant difference between odontogenic tumors, except between UAM and OM (P = 0.041). The difference between OKC and odontogenic tumors was not statistically significant (P > 0.05). The number of MFs was significantly higher in OKC and lower in COC compared to other odontogenic cysts (P = 0.007 and P = 0.045, respectively). Conclusion. The results of the present study suggest a role for MFs in the aggressive behavior of odontogenic lesions. MFs may represent an important target of therapy, especially for aggressive odontogenic lesions. Our findings support the classification of OKC in the category of odontogenic tumors.

The role of vascular endothelial growth factor in proliferation of odontogenic cysts and tumors: An immunohistochemical study.

PubMed

Gupta, Bhavana; Chandra, Shaleen; Singh, Anil; Sah, Kunal; Raj, Vineet; Gupta, Vivek

2016-01-01

Vascular endothelial growth factor (VEGF) is capable of initiating angiogenesis in blood vessels and may act as mitogenic agent for epithelium of odontogenic cysts and tumors. This study was conducted to evaluate the role of epithelial VEGF expression in odontogenic cysts and ameloblastoma and its correlation with argyrophilic nucleolar organizer region counts to assess its role in their biological behavior. In this retrospective cross-sectional study, 45 histologically confirmed cases, 15 cases of each of keratocystic odontogenic tumors (KCOTs), dentigerous cysts, and ameloblastomas were examined for immunohistochemical expression for epithelial VEGF, and argyrophilic nucleolar organizer regions (AgNORs) (used as secondary marker in this study) staining was done for comparing the proliferative capacity with VEGF. KCOT shows mild expression within the basal layers and strong expression in the suprabasal layer whereas, in dentigerous cysts, a majority showed no VEGF expression whereas ameloblastomas showed strong expression in all cases by stellate reticulum-like cells at the center of the follicles and suprabasal layers of epithelium. The results of AgNOR counts were higher in KCOTs as compared to ameloblastoma and least in dentigerous cysts. VEGF expression by the epithelium of odontogenic cysts and tumors may play a role in epithelial proliferation via autocrine mechanism as reflected by increased AgNOR counts. The angiogenic activity via paracrine pathway may be responsible for the difference in growth rate and neoplastic behavior of the lesions.

Immunohistochemical evaluation of myofibroblast density in odontogenic cysts and tumors

PubMed Central

Kouhsoltani, Maryam; Halimi, Monireh; Jabbari, Golchin

2016-01-01

Background. The aim of this study was to investigate myofibroblast (MF) density in a broad spectrum of odontogenic cysts and tumors and the relation between the density of MFs and the clinical behavior of these lesions. Methods. A total of 105 cases of odontogenic lesions, including unicystic ameloblastoma (UAM), solid ameloblastoma (SA), odontogenic keratocyst (OKC), dentigerous cyst (DC), radicular cyst (RC) (15 for each category), and odontogenic myxoma (OM), adenomatoid odontogenic tumor (AOT), calcifying odontogenic cyst (COC) (10 for each category), were immunohistochemically stained with anti-α-smooth muscle actin antibody. The mean percentage of positive cells in 10 high-power fields was considered as MF density for each case. Results. A statistically significant difference was observed in the mean scores between the study groups (P < 0.001). The intensity of MFs was significantly higher in odontogenic tumors compared to odontogenic cysts (P < 0.001). There was no statistically significant difference between odontogenic tumors, except between UAM and OM (P = 0.041). The difference between OKC and odontogenic tumors was not statistically significant (P > 0.05). The number of MFs was significantly higher in OKC and lower in COC compared to other odontogenic cysts (P = 0.007 and P = 0.045, respectively). Conclusion. The results of the present study suggest a role for MFs in the aggressive behavior of odontogenic lesions. MFs may represent an important target of therapy, especially for aggressive odontogenic lesions. Our findings support the classification of OKC in the category of odontogenic tumors. PMID:27092213

Oral immunization of BALB/c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts.

PubMed

Larocque, R; Nakagaki, K; Lee, P; Abdul-Wahid, A; Faubert, G M

2003-10-01

The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

Stem Cells

MedlinePlus

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

The Role of Integrin α6 (CD49f) in Stem Cells: More than a Conserved Biomarker.

PubMed

Krebsbach, Paul H; Villa-Diaz, Luis G

2017-08-01

Stem cells have the capacity for self-renewal and differentiation into specialized cells that form and repopulated all tissues and organs, from conception to adult life. Depending on their capacity for differentiation, stem cells are classified as totipotent (ie, zygote), pluripotent (ie, embryonic stem cells), multipotent (ie, neuronal stem cells, hematopoietic stem cells, epithelial stem cells, etc.), and unipotent (ie, spermatogonial stem cells). Adult or tissue-specific stem cells reside in specific niches located in, or nearby, their organ or tissue of origin. There, they have microenvironmental support to remain quiescent, to proliferate as undifferentiated cells (self-renewal), and to differentiate into progenitors or terminally differentiated cells that migrate from the niche to perform specialized functions. The presence of proteins at the cell surface is often used to identify, classify, and isolate stem cells. Among the diverse groups of cell surface proteins used for these purposes, integrin α6, also known as CD49f, may be the only biomarker commonly found in more than 30 different populations of stem cells, including some cancer stem cells. This broad expression among stem cell populations indicates that integrin α6 may play an important and conserved role in stem cell biology, which is reaffirmed by recent demonstrations of its role maintaining self-renewal of pluripotent stem cells and breast and glioblastoma cancer stem cells. Therefore, this review intends to highlight and synthesize new findings on the importance of integrin α6 in stem cell biology.

Donor CD8+ T Cells Prevent Toxoplasma gondii De-Encystation but Fail To Rescue the Exhausted Endogenous CD8+ T Cell Population

PubMed Central

Bhadra, Rajarshi; Cobb, Dustin A.

2013-01-01

Functional exhaustion of CD8+ T cells due to increased expression of inhibitory molecule PD-1 (Programmed Death-1) causes reactivation of latent disease during later phases of chronic toxoplasmosis. Onset of disease recrudescence results in decreased parasite cyst burden concomitant with parasites undergoing stage conversion from a primarily encysted, quiescent bradyzoite to a fast-replicating, highly motile tachyzoite. Thus, reduced cyst burden is one of the early hallmarks of disease recrudescence. This was further validated by depleting gamma interferon (IFN-γ), a cytokine known to control latent toxoplasmosis, in chronically infected prerecrudescent mice. Since CD8+ T cells (an important source of IFN-γ) lose their functionality during the later phases of chronic toxoplasmosis, we next examined if adoptive transfer of functional CD8+ T cells from acutely infected donors to the chronically infected prerecrudescent hosts could impede parasite de-encystation and rescue exhausted CD8+ T cells. While the transfer of immune CD8+ T cells temporarily restricted the breakdown of cysts, the exhausted endogenous CD8+ T cell population was not rescued. Over time, the donor population got deleted, resulting in parasite de-encystation and host mortality. Considering that donor CD8+ T cells fail to become long-lived, one of the cardinal features of memory CD8+ T cells, it bears the implication that memory CD8 differentiation is impaired during chronic toxoplasmosis. Moreover, our data strongly suggest that while adoptive immunotherapy can prevent parasite de-encystation transiently, reduced antigen burden in the chronic phase by itself is insufficient for rescue of exhausted CD8+ T cells. The conclusions of this study have profound ramifications in designing immunotherapeutics against chronic toxoplasmosis. PMID:23817617

The Complex Cell Wall Composition of Syncytia Induced by Plant Parasitic Cyst Nematodes Reflects Both Function and Host Plant.

PubMed

Zhang, Li; Lilley, Catherine J; Imren, Mustafa; Knox, J Paul; Urwin, Peter E

2017-01-01

Plant-parasitic cyst nematodes induce the formation of specialized feeding structures, syncytia, within their host roots. These unique plant organs serve as the sole nutrient resource for development and reproduction throughout the biotrophic interaction. The multinucleate syncytium, which arises through local dissolution of cell walls and protoplast fusion of multiple adjacent cells, has dense cytoplasm containing numerous organelles, surrounded by thickened outer cell walls that must withstand high turgor pressure. However, little is known about how the constituents of the syncytial cell wall and their conformation support its role during nematode parasitism. We used a set of monoclonal antibodies, targeted to a range of plant cell wall components, to reveal the microstructures of syncytial cell walls induced by four of the most economically important cyst nematode species, Globodera pallida , Heterodera glycines , Heterodera avenae and Heterodera filipjevi , in their respective potato, soybean, and spring wheat host roots. In situ fluorescence analysis revealed highly similar cell wall composition of syncytia induced by G. pallida and H. glycines . Both consisted of abundant xyloglucan, methyl-esterified homogalacturonan and pectic arabinan. In contrast, the walls of syncytia induced in wheat roots by H. avenae and H. filipjevi contain little xyloglucan but are rich in feruloylated xylan and arabinan residues, with variable levels of mixed-linkage glucan. The overall chemical composition of syncytial cell walls reflected the general features of root cell walls of the different host plants. We relate specific components of syncytial cell walls, such as abundant arabinan, methyl-esterification status of pectic homogalacturonan and feruloylation of xylan, to their potential roles in forming a network to support both the strength and flexibility required for syncytium function.

The Complex Cell Wall Composition of Syncytia Induced by Plant Parasitic Cyst Nematodes Reflects Both Function and Host Plant

PubMed Central

Zhang, Li; Lilley, Catherine J.; Imren, Mustafa; Knox, J. Paul; Urwin, Peter E.

2017-01-01

Plant–parasitic cyst nematodes induce the formation of specialized feeding structures, syncytia, within their host roots. These unique plant organs serve as the sole nutrient resource for development and reproduction throughout the biotrophic interaction. The multinucleate syncytium, which arises through local dissolution of cell walls and protoplast fusion of multiple adjacent cells, has dense cytoplasm containing numerous organelles, surrounded by thickened outer cell walls that must withstand high turgor pressure. However, little is known about how the constituents of the syncytial cell wall and their conformation support its role during nematode parasitism. We used a set of monoclonal antibodies, targeted to a range of plant cell wall components, to reveal the microstructures of syncytial cell walls induced by four of the most economically important cyst nematode species, Globodera pallida, Heterodera glycines, Heterodera avenae and Heterodera filipjevi, in their respective potato, soybean, and spring wheat host roots. In situ fluorescence analysis revealed highly similar cell wall composition of syncytia induced by G. pallida and H. glycines. Both consisted of abundant xyloglucan, methyl-esterified homogalacturonan and pectic arabinan. In contrast, the walls of syncytia induced in wheat roots by H. avenae and H. filipjevi contain little xyloglucan but are rich in feruloylated xylan and arabinan residues, with variable levels of mixed-linkage glucan. The overall chemical composition of syncytial cell walls reflected the general features of root cell walls of the different host plants. We relate specific components of syncytial cell walls, such as abundant arabinan, methyl-esterification status of pectic homogalacturonan and feruloylation of xylan, to their potential roles in forming a network to support both the strength and flexibility required for syncytium function. PMID:28680436

Thymic cystic degeneration, pseudoepitheliomatous hyperplasia, and hemorrhage in a dog with brodifacoum toxicosis.

PubMed

Rickman, B H; Gurfield, N

2009-05-01

Thymic cysts with pseudoepitheliomatous hyperplasia are described in a 7-month-old female American Eskimo Dog that died of complications from brodifacoum poisoning. Grossly, there was hemothorax with marked cranial mediastinal hemorrhage. Histologically, thymic lobules were expanded and distorted by irregular cysts, lined by single to multiple layers of plump to slightly attenuated polygonal squamous epithelial cells supported by a basement membrane (pseudoepitheliomatous hyperplasia). The thymus had a paucity of lymphocytes and lacked corticomedullary differentiation. Extensive hemorrhage within the cysts and thymic parenchyma extended into the adjacent adipose tissue. To the authors' knowledge, this is the first report of cystic thymic degeneration with pseudoepitheliomatous hyperplasia in a nonhuman species.

Simulation of lung alveolar epithelial wound healing in vitro

PubMed Central

Kim, Sean H. J.; Matthay, Michael A.; Mostov, Keith; Hunt, C. Anthony

2010-01-01

The mechanisms that enable and regulate alveolar type II (AT II) epithelial cell wound healing in vitro and in vivo remain largely unknown and need further elucidation. We used an in silico AT II cell-mimetic analogue to explore and better understand plausible wound healing mechanisms for two conditions: cyst repair in three-dimensional cultures and monolayer wound healing. Starting with the analogue that validated for key features of AT II cystogenesis in vitro, we devised an additional cell rearrangement action enabling cyst repair. Monolayer repair was enabled by providing ‘cells’ a control mechanism to switch automatically to a repair mode in the presence of a distress signal. In cyst wound simulations, the revised analogue closed wounds by adhering to essentially the same axioms available for alveolar-like cystogenesis. In silico cell proliferation was not needed. The analogue recovered within a few simulation cycles but required a longer recovery time for larger or multiple wounds. In simulated monolayer wound repair, diffusive factor-mediated ‘cell’ migration led to repair patterns comparable to those of in vitro cultures exposed to different growth factors. Simulations predicted directional cell locomotion to be critical for successful in vitro wound repair. We anticipate that with further use and refinement, the methods used will develop as a rigorous, extensible means of unravelling mechanisms of lung alveolar repair and regeneration. PMID:20236957

Synchronous Microscopic Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma of the Adrenal and Lymphoplasmacytic Lymphoma: De Novo Disease or Transformation?

PubMed

Moonim, Mufaddal T; Nasir, Alia; Hubbard, Jonathan; Ketley, Nicholas; Fields, Paul

2017-06-01

Lymphomas arising in the adrenal are rare, and to our knowledge, 2 cases of Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphomas (DLBCL) in an adrenal pseudocyst have been reported. We report an incidental EBV-positive DLBCL arising in an adrenal pseudocyst in a 58-year-old man with a 7-year history of lymphoplasmacytic lymphoma (LPL). The DLBCL was present in the fibrinous exudate, while the LPL resided in the cyst wall. The patient underwent de-roofing of the same cyst 3 years previously; review of histology revealed foci of LPL in the cyst wall, but not of DLBCL. There have been reports of similar microscopic EBV-positive DLBCLs within enclosed cystic spaces. However, all these cases were incidental extranodal primary DLBCLs. Since residual LPL was present alongside DLBCL, with similar light chain restriction, we propose that this may represent transformation, rather than a de novo primary EBV-driven lymphoma.

Immunohistochemical expression of glucose transporter 1 in keratin-producing odontogenic cysts.

PubMed

Vera-Sirera, Beatriz; Forner-Navarro, Leopoldo; Vera-Sempere, Francisco

2016-03-10

Keratin-producing odontogenic cysts (KPOCs) are a group of cystic lesions that are often aggressive, with high rates of recurrence and multifocality. KPOCs included orthokeratinised odontogenic cyst (OOC) and parakeratotic odontogenic cysts, which are now considered true tumours denominated keratocystic odontogenic tumours (KCOTs). GLUT1 is a protein transporter that is involved in the active uptake of glucose across cell membranes and that is overexpressed in tumours in close correlation with the proliferation rate and positron emission tomography (PET) imaging results. A series of 58 keratin-producing odontogenic cysts was evaluated histologically and immunohistochemically in terms of GLUT1 expression. Different data were correlated using the beta regression model in relation to histological type and immunohistochemical expression of GLUT1, which was quantified using two different morphological methods. KPOC cases comprised 12 OOCs and 46 KCOTs, the latter corresponding to 6 syndromic and 40 sporadic KCOTs. GLUT1 expression was very low in OOC cases compared with KCOT cases, with statistical significant differences when quantification was considered. Different GLUT1 localisation patterns were revealed by immunostaining, with the parabasal cells showing higher reactivity in KCOTs. However, among KCOTs cases, GLUT1 expression was unable to establish differences between syndromic and sporadic cases. GLUT1 expression differentiated between OOC and KCOT cases, with significantly higher expression in KCOTs, but did not differentiate between syndromic and sporadic KCOT cases. However, given the structural characteristics of KCOTs, we hypothesised that PET imaging methodology is probably not a useful diagnostic tool for KCOTs. Further studies of GLUT1 expression and PET examination in KCOT series are needed to confirm this last hypothesis.

Drosophila's contribution to stem cell research.

PubMed

Singh, Gyanesh

2015-01-01

The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila.

Drosophila's contribution to stem cell research

PubMed Central

Singh, Gyanesh

2016-01-01

The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila. PMID:26180635

Current overview on dental stem cells applications in regenerative dentistry.

PubMed

Bansal, Ramta; Jain, Aditya

2015-01-01

Teeth are the most natural, noninvasive source of stem cells. Dental stem cells, which are easy, convenient, and affordable to collect, hold promise for a range of very potential therapeutic applications. We have reviewed the ever-growing literature on dental stem cells archived in Medline using the following key words: Regenerative dentistry, dental stem cells, dental stem cells banking, and stem cells from human exfoliated deciduous teeth. Relevant articles covering topics related to dental stem cells were shortlisted and the facts are compiled. The objective of this review article is to discuss the history of stem cells, different stem cells relevant for dentistry, their isolation approaches, collection, and preservation of dental stem cells along with the current status of dental and medical applications.

Comparison of antioxidant enzymes activity and the concentration of uric acid in the saliva of patients with oral cavity cancer, odontogenic cysts and healthy subjects.

PubMed

Giebułtowicz, Joanna; Wroczyński, Piotr; Samolczyk-Wanyura, Danuta

2011-10-01

Chronic inflammation is related to oxidative stress and is still believed to be the cause of carcinogenesis. Patients with oral cavity cancer (OCC) exhibited lower total antioxidant capacity, uric acid (UA) concentration, salivary peroxidise (SPO) and superoxide dismutase (SOD) activity in their saliva than did healthy subjects. This could be a risk factor for tumour induction. Odontogenic cysts also arise in response to locally acting proinflammatory factors, for example, a gangrenous tooth. Furthermore, cyst development is accompanied by chronic inflammation. There are some reports in the literature concerning primary tumours such as squamous cell carcinomas arising from odontogenic cysts. The reason for this transformation is still unknown. The aim of this study was to compare the status of the antioxidant defence system in the saliva of the group with odontogenic cysts and OCC with that of the healthy control. Saliva samples were collected in the morning. SOD, SPO activity and UA concentration were determined using standard methods. Patients with odontogenic cysts and OCC exhibited lower activity of major antioxidants in their saliva (SPO, UA) than did healthy people. SOD activity and age are the main factors that distinguish these diseases. Discriminant function analysis showed that once data such as antioxidant status of saliva, age and smoking status are known 80% cases can be correctly classified as healthy, 80% as having odontogenic cysts and 40% as cancerous. To conclude, the decrease in concentrations of major antioxidants in the saliva of patients with cysts may increase the risk of neoplastic transformation especially in advanced age. © 2011 John Wiley & Sons A/S.

The longest telomeres: a general signature of adult stem cell compartments

PubMed Central

Flores, Ignacio; Canela, Andres; Vera, Elsa; Tejera, Agueda; Cotsarelis, George; Blasco, María A.

2008-01-01

Identification of adult stem cells and their location (niches) is of great relevance for regenerative medicine. However, stem cell niches are still poorly defined in most adult tissues. Here, we show that the longest telomeres are a general feature of adult stem cell compartments. Using confocal telomere quantitative fluorescence in situ hybridization (telomapping), we find gradients of telomere length within tissues, with the longest telomeres mapping to the known stem cell compartments. In mouse hair follicles, we show that cells with the longest telomeres map to the known stem cell compartments, colocalize with stem cell markers, and behave as stem cells upon treatment with mitogenic stimuli. Using K15-EGFP reporter mice, which mark hair follicle stem cells, we show that GFP-positive cells have the longest telomeres. The stem cell compartments in small intestine, testis, cornea, and brain of the mouse are also enriched in cells with the longest telomeres. This constitutes the description of a novel general property of adult stem cell compartments. Finally, we make the novel finding that telomeres shorten with age in different mouse stem cell compartments, which parallels a decline in stem cell functionality, suggesting that telomere loss may contribute to stem cell dysfunction with age. PMID:18283121

Bloom of the Yessotoxin producing dinoflagellate Protoceratium reticulatum (Dinophyceae) in Northern Chile

NASA Astrophysics Data System (ADS)

Álvarez, Gonzalo; Uribe, Eduardo; Díaz, Rosario; Braun, Mauricio; Mariño, Carmen; Blanco, Juan

2011-05-01

In summer 2007, a dinoflagellate preliminarily identified as Protoceratium reticulatum bloomed in Bahía Mejillones, northern Chile. Phytoplankton samples were analyzed in detail by light and scanning electron microscopy revealing the presence of resting cyst and motile cells of P. reticulatum. Oceanographic and phytoplankton data suggest that the bloom was initiated offshore by motile cells and germinated cysts during an upwelling pulse. These cells were advected into the bay when upwelling relaxed and grew without any relevant competitor. Phytoplankton net samples were found to contain yessotoxin as the only toxin in an estimated proportion of 0.2 and 0.4 pg cell - 1 , thus confirming that P. reticulatum is a source of yessotoxin in northern Chilean waters and consequently that it poses a risk for human health and mollusk exploitation in the area.

Context clues: the importance of stem cell-material interactions

PubMed Central

Murphy, William L.

2014-01-01

Understanding the processes by which stem cells give rise to de novo tissues is an active focus of stem cell biology and bioengineering disciplines. Instructive morphogenic cues surrounding the stem cell during morphogenesis create what is referred to as the stem cell microenvironment. An emerging paradigm in stem cell bioengineering involves “biologically driven assembly,” in which stem cells are encouraged to largely define their own morphogenesis processes. However, even in the case of biologically driven assembly, stem cells do not act alone. The properties of the surrounding microenvironment can be critical regulators of cell fate. Stem cell-material interactions are among the most well-characterized microenvironmental effectors of stem cell fate, and they establish a signaling “context” that can define the mode of influence for morphogenic cues. Here we describe illustrative examples of cell-material interactions that occur during in vitro stem cell studies, with an emphasis on how cell-material interactions create instructive contexts for stem cell differentiation and morphogenesis. PMID:24369691

Cancer stem cells and differentiation therapy.

PubMed

Jin, Xiong; Jin, Xun; Kim, Hyunggee

2017-10-01

Cancer stem cells can generate tumors from only a small number of cells, whereas differentiated cancer cells cannot. The prominent feature of cancer stem cells is its ability to self-renew and differentiate into multiple types of cancer cells. Cancer stem cells have several distinct tumorigenic abilities, including stem cell signal transduction, tumorigenicity, metastasis, and resistance to anticancer drugs, which are regulated by genetic or epigenetic changes. Like normal adult stem cells involved in various developmental processes and tissue homeostasis, cancer stem cells maintain their self-renewal capacity by activating multiple stem cell signaling pathways and inhibiting differentiation signaling pathways during cancer initiation and progression. Recently, many studies have focused on targeting cancer stem cells to eradicate malignancies by regulating stem cell signaling pathways, and products of some of these strategies are in preclinical and clinical trials. In this review, we describe the crucial features of cancer stem cells related to tumor relapse and drug resistance, as well as the new therapeutic strategy to target cancer stem cells named "differentiation therapy."

Light microscopic study of periapical lesions associated with asymptomatic apical periodontitis.

PubMed

Kabak, S L; Kabak, Y S; Anischenko, S L

2005-04-01

The purpose of the study has been to evaluate the degree of chronic inflammation in tissues surrounding the apex of the tooth root in patients with apical periodontitis in the remission phase. The material included 37 apical granulomas and radicular cysts obtained as a result of apiectomy, and 20 teeth which were removed together with the focus of the periapical inflammation. Routine histological techniques, as well as the immunofluorescent and immuno-chemical methods were used to examine the material. Despite the absence of clinical symptoms in 23 of 57 cases, the morphological signs of chronic inflammation were observed in the apical area of the tooth root. Morphological signs of viral invasion of epithelial and stromal cells in the radicular cyst wall were revealed in six cases. The presence of the virus of Herpes simplex I in epithelial cells (five cases) and adenoviral invasion (one case) was confirmed by immuno-fluorescent and immuno-chemical methods. Histological examination often reveals morphological signs of an active inflammatory process in the periapical tissues of patients treated during clinical remission. In our opinion, the presence of viruses in the epithelial cells of the radicular cyst may contribute to the persistence of the active stage of the inflammatory process.

Orpk mouse model of polycystic kidney disease reveals essential role of primary cilia in pancreatic tissue organization.

PubMed

Cano, David A; Murcia, Noel S; Pazour, Gregory J; Hebrok, Matthias

2004-07-01

Polycystic kidney disease (PKD) includes a group of disorders that are characterized by the presence of cysts in the kidney and other organs, including the pancreas. Here we show that in orpk mice, a model system for PKD that harbors a mutation in the gene that encodes the polaris protein, pancreatic defects start to occur at the end of gestation, with an initial expansion of the developing pancreatic ducts. Ductal dilation continues rapidly after birth and results in the formation of large, interconnected cysts. Expansion of pancreatic ducts is accompanied by apoptosis of neighboring acinar cells, whereas endocrine cell differentiation and islet formation appears to be unaffected. Polaris has been shown to co-localize with primary cilia, and these structures have been implicated in the formation of renal cysts. In the orpk pancreas, cilia numbers are reduced and cilia length is decreased. Expression of polycystin-2, a protein involved in PKD, is mislocalized in orpk mice. Furthermore, the cellular localization of beta-catenin, a protein involved in cell adhesion and Wnt signaling, is altered. Thus, polaris and primary cilia function are required for the maturation and maintenance of proper tissue organization in the pancreas.

Clinical trials for stem cell transplantation: when are they needed?

PubMed

Van Pham, Phuc

2016-04-27

In recent years, both stem cell research and the clinical application of these promising cells have increased rapidly. About 1000 clinical trials using stem cells have to date been performed globally. More importantly, more than 10 stem cell-based products have been approved in some countries. With the rapid growth of stem cell applications, some countries have used clinical trials as a tool to diminish the rate of clinical stem cell applications. However, the point at which stem cell clinical trials are essential remains unclear. This commentary discusses when stem cell clinical trials are essential for stem cell transplantation therapies.

Stem cells - biological update and cell therapy progress

PubMed Central

GIRLOVANU, MIHAI; SUSMAN, SERGIU; SORITAU, OLGA; RUS-CIUCA, DAN; MELINCOVICI, CARMEN; CONSTANTIN, ANNE-MARIE; MIHU, CARMEN MIHAELA

2015-01-01

In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods to prevent teratoma formation or the ethical and religious issues regarding especially the embryonic stem cell research. The direct differentiation of stem cells into specialized cells: cardiac myocytes, neural cells, pancreatic islets cells, may represent an option in treating incurable diseases such as: neurodegenerative diseases, type I diabetes, hematologic or cardiac diseases. Nevertheless, stem cell-based therapies, based on stem cell transplantation, remain mainly at the experimental stages and their major limitation is the development of teratoma and cancer after transplantation. The induced pluripotent stem cells (hiPSCs) represent a prime candidate for future cell therapy research because of their significant self-renewal and differentiation potential and the lack of ethical issues. This article presents an overview of the biological advances in the study of stem cells and the current progress made in the field of regenerative medicine. PMID:26609255

Establishment of mouse expanded potential stem cells

PubMed Central

Gao, Xuefei; Antunes, Liliana; Yu, Yong; Zhu, Zhexin; Wang, Juexuan; Kolodziejczyk, Aleksandra A.; Campos, Lia S.; Wang, Cui; Yang, Fengtang; Zhong, Zhen; Fu, Beiyuan; Eckersley-Maslin, Melanie A.; Woods, Michael; Tanaka, Yosuke; Chen, Xi; Wilkinson, Adam C.; Bussell, James; White, Jacqui; Ramirez-Solis, Ramiro; Reik, Wolf; Göttgens, Berthold; Teichmann, Sarah A.; Tam, Patrick P. L.; Nakauchi, Hiromitsu; Zou, Xiangang; Lu, Liming; Liu, Pentao

2018-01-01

Mouse embryonic stem cells derived from the epiblast1 contribute to the somatic lineages and the germline but are excluded from the extra-embryonic tissues that are derived from the trophectoderm and the primitive endoderm2 upon reintroduction to the blastocyst. Here we report that cultures of expanded potential stem cells can be established from individual eight-cell blastomeres, and by direct conversion of mouse embryonic stem cells and induced pluripotent stem cells. Remarkably, a single expanded potential stem cell can contribute both to the embryo proper and to the trophectoderm lineages in a chimaera assay. Bona fide trophoblast stem cell lines and extra-embryonic endoderm stem cells can be directly derived from expanded potential stem cells in vitro. Molecular analyses of the epigenome and single-cell transcriptome reveal enrichment for blastomere-specific signature and a dynamic DNA methylome in expanded potential stem cells. The generation of mouse expanded potential stem cells highlights the feasibility of establishing expanded potential stem cells for other mammalian species. PMID:29019987

Oral lymphoepithelial cyst: A clinicopathological study of 26 cases and review of the literature

PubMed Central

Sykara, Maria; Ntovas, Panagiotis; Tosios, Konstantinos I.; Sklavounou, Alexandra

2017-01-01

Introduction Τo describe the clinicopathological features of 26 oral lymphoepithelial cysts (LECs) and review the literature. Material and Methods Twenty-six cases of oral LECs diagnosed during a 37-year period were retrospectively collected. The patients’ gender and age, as well as the main clinical features of the cysts were retrieved from the requisition forms. The main microscopic features were recorded after reevaluation of all cases. Pubmed and Google Scholar electronic databases were searched with the key word “oral LEC”. Inclusion criteria were the microscopic confirmation of LEC diagnosis and the report at least two of three main clinical features (gender, age and cyst’s location). Results The 26 oral LECs represented 0.08% of 31,564 biopsies accessioned during the study period. They affected 25 patients, 14 females and 11 males with a mean age of 33.04±9.81 years. They appeared as smooth (92%) nodules, with soft (24%) or firm (76%) consistency and normal (28%), yellow to normal (20%), yellow (32%) or white (20%) hue, in the tongue (69.23%) or the floor of mouth (30.77%). They were covered by parakeratinized squamous (92.31%) or non-keratinized (7.69%) epithelium and contained desquamated epithelial cells, amorphous eosinophilic material and/or inflammatory cells (100%). The lymphoid tissue surrounded the cystic cavity partially (34.62%) or completely (65.38%), often in a follicular pattern with prominent germinal centers (53.85%). Literature review yielded 316 cases of oral LECs derived from 25 case reports, 3 case studies/retrospective studies with detailed information for each case and 7 studies with summarized data. Conclusions Oral LEC is a pathologic entity with discrete clinical presentation that is, however, commonly misdiagnosed in clinical practice as other, mostly benign, entities. Its pathogenesis remains obscure, as its clinicopathologic features are consistent with both theories suggested up to date. Key words:Oral lymphoepithelial cyst; developmental cyst; non odontogenic cyst; lymphoid tissue; oral tonsil. PMID:28936296

Immunoexpression of interleukin 17, transforming growth factor β1, and forkhead box P3 in periapical granulomas, radicular cysts, and residual radicular cysts.

PubMed

Andrade, Ana Luiza Dias Leite de; Nonaka, Cassiano Francisco Weege; Gordón-Núñez, Manuel Antonio; Freitas, Roseana de Almeida; Galvão, Hébel Cavalcanti

2013-08-01

Different cell types and cytokines have been identified as contributors to the formation of periapical lesions. In this perspective, this study aimed to evaluate the immunoexpression of interleukin (IL)-17, transforming growth factor (TGF)-β1, and the forkhead box P3 (FoxP3) in periapical lesions, correlating them with the type of lesion, the intensity of the inflammatory infiltrate, and the thickness of the cystic epithelial lining. Twenty periapical granulomas (PGs), 20 radicular cysts (RCs), and 20 residual radicular cysts (RRCs) were submitted to immunohistochemical analysis using anti-IL-17, anti-TGF-β1, and anti-FoxP3 antibodies. In comparison with PGs and RCs, RRCs exhibited a lower immunoexpression of IL-17 and TGF-β1 (P = .021 and P < .001, respectively). The number of FoxP3+ cells increased in this order: RRCs, RCs, and PGs (P < .001). In comparison with lesions with inflammatory infiltrates grades I and II, lesions with inflammatory infiltrate grade III exhibited a higher number of FoxP3+ cells (P = .002). Similarly, in comparison with lesions with inflammatory infiltrates grades II and III, lesions with inflammatory infiltrate grade I showed a tendency for a lower expression of IL-17 and TGF-β1 (P = .085 and P = .051, respectively). For all groups, there was a positive correlation between the immunoexpressions of IL-17 and TGF-β1 (P < .05). Positive correlations between the number of FoxP3+ cells and the immunoexpressions of IL-17 and TGF-β1 (P < .05) were found only in PGs. Th17 and Treg cells seem to interact at the site of injury, suggesting the involvement of proinflammatory and immunoregulatory cytokines in the pathogenesis of periapical lesions. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Analysis of gene expression profiles for cell wall modifying proteins and ACC synthases in soybean cyst nematode colonized roots, adventitious rooting hypocotyls, root tips, flooded roots, and IBA and ACC treatment roots

USDA-ARS?s Scientific Manuscript database

We hypothesized that soybean cyst nematode (SCN) co-opts a part or all of one or more innate developmental process in soybean to establish its feeding structure, syncytium, in soybean roots. The syncytium in soybean roots is formed in a predominantly lateral direction within the vascular bundle by ...

Reverse Osmosis Water Purification Unit: Efficacy of Cartridge Filters for Removal of Bacteria and Protozoan Cysts when Ro Elements are Bypassed

DTIC Science & Technology

1993-04-01

were Klebsiella terrigena, Cryptosporidium parvum oocysts, Rhodotorula rubra, and 3.7 pm latex beads. Challenge waters were dechlorinated tap water and...The morphological and size characteristics of Rhodotorula rubra (ATCC 36053) made the yeast suitable as a protozoan cyst simulant. The yeast cells...representative enteric bacterium), Cryptosporidium parvum (an enteric protozoan pathogen) oocysts, Rhodotorula rubra (a yeast, used to test prefilters only

Adult Stem Cell Therapy for Stroke: Challenges and Progress

PubMed Central

Bang, Oh Young; Kim, Eun Hee; Cha, Jae Min; Moon, Gyeong Joon

2016-01-01

Stroke is one of the leading causes of death and physical disability among adults. It has been 15 years since clinical trials of stem cell therapy in patients with stroke have been conducted using adult stem cells like mesenchymal stem cells and bone marrow mononuclear cells. Results of randomized controlled trials showed that adult stem cell therapy was safe but its efficacy was modest, underscoring the need for new stem cell therapy strategies. The primary limitations of current stem cell therapies include (a) the limited source of engraftable stem cells, (b) the presence of optimal time window for stem cell therapies, (c) inherited limitation of stem cells in terms of growth, trophic support, and differentiation potential, and (d) possible transplanted cell-mediated adverse effects, such as tumor formation. Here, we discuss recent advances that overcome these hurdles in adult stem cell therapy for stroke. PMID:27733032

Immunity in the spleen and blood of mice immunized with irradiated Toxoplasma gondii tachyzoites.

PubMed

Zorgi, Nahiara Esteves; Galisteo, Andrés Jimenez; Sato, Maria Notomi; do Nascimento, Nanci; de Andrade, Heitor Franco

2016-08-01

Toxoplasma gondii infection induces a strong and long-lasting immune response that is able to prevent most reinfections but allows tissue cysts. Irradiated, sterilized T. gondii tachyzoites are an interesting vaccine, and they induce immunity that is similar to infection, but without cysts. In this study, we evaluated the cellular immune response in the blood and spleen of mice immunized with this preparation by mouth (v.o.) or intraperitoneally (i.p.) and analyzed the protection after challenge with viable parasites. BALB/c mice were immunized with three i.p. or v.o. doses of irradiated T. gondii tachyzoites. Oral challenge with ten cysts of the ME-49 or VEG strain at 90 days after the last dose resulted in high levels of protection with low parasite burden in the immunized animals. There were higher levels of specific IgG, IgA and IgM antibodies in the serum, and the i.p. immunized mice had higher levels of the high-affinity IgG and IgM antibodies than the orally immunized mice, which had more high-affinity IgA antibodies. B cells (CD19(+)), plasma cells (CD138(+)) and the CD4(+) and CD8(+) T cell populations were increased in both the blood and spleen. Cells from the spleen of the i.p. immunized mice also showed antigen-induced production of interleukin-10 (IL-10), interferon gamma (IFN-γ) and interleukin 4 (IL-4). The CD4(+) T cells, B cells and likely CD8(+) T cells from the spleens of the i.p. immunized mice proliferated with a specific antigen. The protection was correlated with the spleen and blood CD8(+) T cell, high-affinity IgG and IgM and antigen-induced IL-10 and IL-4 production. Immunization with irradiated T. gondii tachyzoites induces an immune response that is mediated by B cells and CD4(+) and CD8(+) T cells, with increased humoral and cellular immune responses that are necessary for host protection after infection. The vaccine is similar to natural infection, but free of tissue cysts; this immunity restrains infection at challenge and can be an attractive and efficient model for vaccine development in toxoplasmosis.

Two sides of the same coin? Unraveling subtle differences between human embryonic and induced pluripotent stem cells by Raman spectroscopy.

PubMed

Parrotta, Elvira; De Angelis, Maria Teresa; Scalise, Stefania; Candeloro, Patrizio; Santamaria, Gianluca; Paonessa, Mariagrazia; Coluccio, Maria Laura; Perozziello, Gerardo; De Vitis, Stefania; Sgura, Antonella; Coluzzi, Elisa; Mollace, Vincenzo; Di Fabrizio, Enzo Mario; Cuda, Giovanni

2017-11-28

Human pluripotent stem cells, including embryonic stem cells and induced pluripotent stem cells, hold enormous promise for many biomedical applications, such as regenerative medicine, drug testing, and disease modeling. Although induced pluripotent stem cells resemble embryonic stem cells both morphologically and functionally, the extent to which these cell lines are truly equivalent, from a molecular point of view, remains controversial. Principal component analysis and K-means cluster analysis of collected Raman spectroscopy data were used for a comparative study of the biochemical fingerprint of human induced pluripotent stem cells and human embryonic stem cells. The Raman spectra analysis results were further validated by conventional biological assays. Raman spectra analysis revealed that the major difference between human embryonic stem cells and induced pluripotent stem cells is due to the nucleic acid content, as shown by the strong positive peaks at 785, 1098, 1334, 1371, 1484, and 1575 cm -1 , which is enriched in human induced pluripotent stem cells. Here, we report a nonbiological approach to discriminate human induced pluripotent stem cells from their native embryonic stem cell counterparts.

The dynamics of cereal cyst nematode infection differ between susceptible and resistant barley cultivars and lead to changes in (1,3;1,4)-β-glucan levels and HvCslF gene transcript abundance.

PubMed

Aditya, Jessika; Lewis, John; Shirley, Neil J; Tan, Hwei-Ting; Henderson, Marilyn; Fincher, Geoffrey B; Burton, Rachel A; Mather, Diane E; Tucker, Matthew R

2015-07-01

Heterodera avenae (cereal cyst nematode, CCN) infects the roots of barley (Hordeum vulgare) forming syncytial feeding sites. In resistant host plants, relatively few females develop to maturity. Little is known about the physiological and biochemical changes induced during CCN infection. Responses to CCN infection were investigated in resistant (Rha2) and susceptible barley cultivars through histological, compositional and transcriptional analysis. Two phases were identified that influence CCN viability, including feeding site establishment and subsequent cyst maturation. Syncytial development progressed faster in the resistant cultivar Chebec than in the susceptible cultivar Skiff, and was accompanied by changes in cell wall polysaccharide abundance, particularly (1,3;1,4)-β-glucan. Transcriptional profiling identified several glycosyl transferase genes, including CELLULOSE SYNTHASE-LIKE F10 (HvCslF10), which may contribute to differences in polysaccharide abundance between resistant and susceptible cultivars. In barley, Rha2-mediated CCN resistance drives rapid deterioration of CCN feeding sites, specific changes in cell wall-related transcript abundance and changes in cell wall composition. During H. avenae infection, (1,3;1,4)-β-glucan may influence CCN feeding site development by limiting solute flow, similar to (1,3)-β-glucan during dicot cyst nematode infections. Dynamic transcriptional changes in uncharacterized HvCslF genes, possibly involved in (1,3;1,4)-β-glucan synthesis, suggest a role for these genes in the CCN infection process. © 2015 The University of Adelaide. New Phytologist © 2015 New Phytologist Trust.

A family business: stem cell progeny join the niche to regulate homeostasis.

PubMed

Hsu, Ya-Chieh; Fuchs, Elaine

2012-01-23

Stem cell niches, the discrete microenvironments in which the stem cells reside, play a dominant part in regulating stem cell activity and behaviours. Recent studies suggest that committed stem cell progeny become indispensable components of the niche in a wide range of stem cell systems. These unexpected niche inhabitants provide versatile feedback signals to their stem cell parents. Together with other heterologous cell types that constitute the niche, they contribute to the dynamics of the microenvironment. As progeny are often located in close proximity to stem cell niches, similar feedback regulations may be the underlying principles shared by different stem cell systems.

A family business: stem cell progeny join the niche to regulate homeostasis

PubMed Central

Hsu, Ya-Chieh; Fuchs, Elaine

2012-01-01

Stem cell niches, the discrete microenvironments in which the stem cells reside, play a dominant part in regulating stem cell activity and behaviours. Recent studies suggest that committed stem cell progeny become indispensable components of the niche in a wide range of stem cell systems. These unexpected niche inhabitants provide versatile feedback signals to their stem cell parents. Together with other heterologous cell types that constitute the niche, they contribute to the dynamics of the microenvironment. As progeny are often located in close proximity to stem cell niches, similar feedback regulations may be the underlying principles shared by different stem cell systems. PMID:22266760

Stem Cell Therapy for Erectile Dysfunction.

PubMed

Matz, Ethan L; Terlecki, Ryan; Zhang, Yuanyuan; Jackson, John; Atala, Anthony

2018-04-06

The prevalence of erectile dysfunction (ED) is substantial and continues to rise. Current therapeutics for ED consist of oral medications, intracavernosal injections, vacuum erection devices, and penile implants. While such options may manage the disease state, none of these modalities, however, restore function. Stem cell therapy has been evaluated for erectile restoration in animal models. These cells have been derived from multiple tissues, have varied potential, and may function via local engraftment or paracrine signaling. Bone marrow-derived stem cells (BMSC) and adipose-derived stem cells (ASC) have both been used in these models with noteworthy effects. Herein, we will review the pathophysiology of ED, animal models, current and novel stem-cell based therapeutics, clinical trials and areas for future research. The relevant literature and contemporary data using keywords, "stem cells and erectile dysfunction" was reviewed. Examination of evidence supporting the association between erectile dysfunction and adipose derived stem cells, bone marrow derived stem cells, placental stem cells, urine stem cells and stem cell therapy respectively. Placental-derived stem cells and urine-derived stem cells possess many similar properties as BMSC and ASC, but the methods of acquisition are favorable. Human clinical trials have already demonstrated successful use of stem cells for improvement of erectile function. The future of stem cell research is constantly being evaluated, although, the evidence suggests a place for stem cells in erectile dysfunction therapeutics. Matz EL, Terlecki R, Zhang Y, et al. Stem Cell Therapy for Erectile Dysfunction. Sex Med Rev 2018;XX:XXX-XXX. Copyright © 2018 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

A new prospect in cancer therapy: targeting cancer stem cells to eradicate cancer.

PubMed

Chen, Li-Sha; Wang, An-Xin; Dong, Bing; Pu, Ke-Feng; Yuan, Li-Hua; Zhu, Yi-Min

2012-12-01

According to the cancer stem cell theory, cancers can be initiated by cancer stem cells. This makes cancer stem cells prime targets for therapeutic intervention. Eradicating cancer stem cells by efficient targeting agents may have the potential to cure cancer. In this review, we summarize recent breakthroughs that have improved our understanding of cancer stem cells, and we discuss the therapeutic strategy of targeting cancer stem cells, a promising future direction for cancer stem cell research.

Adult bone marrow-derived stem cells for organ regeneration and repair.

PubMed

Tögel, Florian; Westenfelder, Christof

2007-12-01

Stem cells have been recognized as a potential tool for the development of innovative therapeutic strategies. There are in general two types of stem cells, embryonic and adult stem cells. While embryonic stem cell therapy has been riddled with problems of allogeneic rejection and ethical concerns, adult stem cells have long been used in the treatment of hematological malignancies. With the recognition of additional, potentially therapeutic characteristics, bone marrow-derived stem cells have become a tool in regenerative medicine. The bone marrow is an ideal source of stem cells because it is easily accessible and harbors two types of stem cells. Hematopoietic stem cells give rise to all blood cell types and have been shown to exhibit plasticity, while multipotent marrow stromal cells are the source of osteocytes, chondrocytes, and fat cells and have been shown to support and generate a large number of different cell types. This review describes the general characteristics of these stem cell populations and their current and potential future applications in regenerative medicine. 2007 Wiley-Liss, Inc

Immunoexpression of tryptase-positive mast cells in periapical granulomas and radicular cysts.

PubMed

Costa Neto, H; de Andrade, A L D L; Gordón-Núñez, M A; Freitas, R de A; Galvão, H C

2015-08-01

To evaluate and compare the immunoexpression of tryptase in samples of periapical granulomas (PGs) and radicular cysts (RCs) correlating it with the type of lesion, localization, intensity of the inflammatory infiltrate and thickness of the cystic epithelial lining, in order to gain insight into the phlogistic role of these cells in the lesions studied. Twenty-five PGs and twenty-five RCs obtained from human teeth without endodontic treatment were submitted to morphological and immunohistochemical analysis using anti-tryptase antibody. Mast cells were identified and counted in three regions: intra-epithelial, central/superficial and deep portions. The data were analysed using the Mann-Whitney U-test (P < 0.05). In comparison with RCs, PGs exhibited higher immunoexpression of tryptase-positive mast cells located in both central/superficial and deep regions (P < 0.001 and P < 0.001, respectively). When considering the total number of mast cells and disregarding the location, the number of tryptase-positive mast cells increased gradually from RCs to PGs (P < 0.001). Lesions with inflammatory infiltrate grade III had greater number of tryptase-positive mast cells located in both central/superficial and deep regions than lesions with inflammatory infiltrates grade II (P = 0.045 and P = 0.025). When the location was ignored, the lesions with inflammatory infiltrate grade III also exhibited higher immunostaining of tryptase-positive mast cells (P = 0.01). Tryptase-positive mast cells were present in chronic periapical lesions in a larger number in periapical granulomas than in radicular cysts, in both central/superficial and deep regions. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Stem cells.

PubMed

Behr, Björn; Ko, Sae Hee; Wong, Victor W; Gurtner, Geoffrey C; Longaker, Michael T

2010-10-01

Stem cells are self-renewing cells capable of differentiating into multiple cell lines and are classified according to their origin and their ability to differentiate. Enormous potential exists in use of stem cells for regenerative medicine. To produce effective stem cell-based treatments for a range of diseases, an improved understanding of stem cell biology and better control over stem cell fate are necessary. In addition, the barriers to clinical translation, such as potential oncologic properties of stem cells, need to be addressed. With renewed government support and continued refinement of current stem cell methodologies, the future of stem cell research is exciting and promises to provide novel reconstructive options for patients and surgeons limited by traditional paradigms.

Some Ethical Concerns About Human Induced Pluripotent Stem Cells.

PubMed

Zheng, Yue Liang

2016-10-01

Human induced pluripotent stem cells can be obtained from somatic cells, and their derivation does not require destruction of embryos, thus avoiding ethical problems arising from the destruction of human embryos. This type of stem cell may provide an important tool for stem cell therapy, but it also results in some ethical concerns. It is likely that abnormal reprogramming occurs in the induction of human induced pluripotent stem cells, and that the stem cells generate tumors in the process of stem cell therapy. Human induced pluripotent stem cells should not be used to clone human beings, to produce human germ cells, nor to make human embryos. Informed consent should be obtained from patients in stem cell therapy.

Cystic tumors of the liver: A practical approach

PubMed Central

Poggio, Paolo Del; Buonocore, Marco

2008-01-01

Biliary cyst tumors (cystadenoma and cystadeno-carcinoma) are an indication for liver resection. They account for only 5% of all solitary cystic lesions of the liver, but differential diagnosis with multiloculated or complicated biliary cysts, atypical hemangiomas, hamartomas and lymphangiomas may be difficult. The most frequent challenge is to differentiate biliary cyst tumors from hemorrhagic cysts. Computerized tomography (CT) and magnetic resonance imaging (MRI) are often not diagnostic and in these cases fine needle aspiration (FNA) is used to confirm the presence of atypical biliary cells. FNA, however, lacks adequate sensitivity and specificity and should always be used in conjunction with imaging. Pre-operative differentiation of cystadenoma from cystadenocarcinoma is impossible and surgery must be performed if a biliary cyst tumor is suspected. When multiple cystic lesions are observed throughout the liver parenchyma, it is important to exclude liver metastasis, of which colonic cancer is the most common primary site. Multiple biliary hamartomas (von Meyenburg complex) can appear as a mixture of solid and cystic lesions and can be confused with cystic metastasis. Strong and uniform T2 hyperintensity on MRI is usually diagnostic, but occasionally a percutaneous biopsy may be required. PMID:18595127

Influence of surgical decompression on the expression of inflammatory and tissue repair biomarkers in periapical cysts.

PubMed

Rodrigues, Janderson Teixeira; Dos Santos Antunes, Henrique; Armada, Luciana; Pires, Fábio Ramôa

2017-12-01

The biologic effects of surgical decompression on the epithelium and connective tissues of periapical cysts are not fully understood. The aim of this study was to evaluate the expression of tissue repair and inflammatory biomarkers in periapical cysts before and after surgical decompression. Nine specimens of periapical cysts treated with decompression before undergoing complete enucleation were immunohistochemically analyzed to investigate the expression of interleukin-1β, tumor necrosis factor-α, transforming growth factor-β1, matrix metalloproteinase-9, Ki-67, and epidermal growth factor receptor. Expression of the biomarkers was classified as positive, focal, or negative. Ki-67 immunoexpression was calculated as a cell proliferation index. The expression of the biomarkers was compared in the specimens from decompression and from the final surgical procedure. Computed tomography demonstrated that volume was reduced in all cysts after decompression. There were no differences in the immunoexpression of the proinflammatory and tissue repair biomarkers when comparing the specimens obtained before and after the decompression. Surgical decompression was efficient in reducing the volume of periapical cysts before complete enucleation. When comparing the specimens obtained from surgical decompression and from complete surgical removal, the immunohistochemical analysis did not show a decrease in proinflammatory biomarkers; neither did it show an increase in tissue repair biomarkers. Copyright © 2017 Elsevier Inc. All rights reserved.

Laser biomodulation on stem cells

NASA Astrophysics Data System (ADS)

Liu, Timon C.; Duan, Rui; Li, Yan; Li, Xue-Feng; Tan, Li-Ling; Liu, Songhao

2001-08-01

Stem cells are views from the perspectives of their function, evolution, development, and cause. Counterintuitively, most stem cells may arise late in development, to act principally in tissue renewal, thus ensuring an organisms long-term survival. Surprisingly, recent reports suggest that tissue-specific adult stem cells have the potential to contribute to replenishment of multiple adult tissues. Stem cells are currently in the news for two reasons: the successful cultivation of human embryonic stem cell lines and reports that adult stem cells can differentiate into developmentally unrelated cell types, such as nerve cells into blood cells. The spotlight on stem cells has revealed gaps in our knowledge that must be filled if we are to take advantage of their full potential for treating devastating degenerative diseases such as Parkinsons's disease and muscular dystrophy. We need to know more about the intrinsic controls that keep stem cells as stem cells or direct them along particular differentiation pathways. Such intrinsic regulators are, in turn, sensitive to the influences of the microenvironment, or niche, where stem cells normally reside. Both intrinsic and extrinsic signals regular stem cell fate and some of these signals have now been identified. Vacek et al and Wang et al have studied the effect of low intensity laser on the haemopoietic stem cells in vitro. There experiments show there is indeed the effect of low intensity laser on the haemopoietic stem cells in vitro, and the present effect is the promotion of haemopoietic stem cells proliferation. In other words, low intensity laser irradiation can act as an extrinsic signal regulating stem cell fate. In this paper, we study how low intensity laser can be used to regulate stem cell fate from the viewpoint of collective phototransduction.

Potential antitumor therapeutic strategies of human amniotic membrane and amniotic fluid-derived stem cells.

PubMed

Kang, N-H; Hwang, K-A; Kim, S U; Kim, Y-B; Hyun, S-H; Jeung, E-B; Choi, K-C

2012-08-01

As stem cells are capable of self-renewal and can generate differentiated progenies for organ development, they are considered as potential source for regenerative medicine and tissue replacement after injury or disease. Along with this capacity, stem cells have the therapeutic potential for treating human diseases including cancers. According to the origins, stem cells are broadly classified into two types: embryonic stem cells (ESCs) and adult stem cells. In terms of differentiation potential, ESCs are pluripotent and adult stem cells are multipotent. Amnion, which is a membranous sac that contains the fetus and amniotic fluid and functions in protecting the developing embryo during gestation, is another stem cell source. Amnion-derived stem cells are classified as human amniotic membrane-derived epithelial stem cells, human amniotic membrane-derived mesenchymal stem cells and human amniotic fluid-derived stem cells. They are in an intermediate stage between pluripotent ESCs and lineage-restricted adult stem cells, non-tumorigenic, and contribute to low immunogenicity and anti-inflammation. Furthermore, they are easily available and do not cause any controversial issues in their recovery and applications. Not only are amnion-derived stem cells applicable in regenerative medicine, they have anticancer capacity. In non-engineered stem cells transplantation strategies, amnion-derived stem cells effectively target the tumor and suppressed the tumor growth by expressing cytotoxic cytokines. Additionally, they also have a potential as novel delivery vehicles transferring therapeutic genes to the cancer formation sites in gene-directed enzyme/prodrug combination therapy. Owing to their own advantageous properties, amnion-derived stem cells are emerging as a new candidate in anticancer therapy.

In vitro differentiation of primordial germ cells and oocyte-like cells from stem cells.

PubMed

Costa, José J N; Souza, Glaucinete B; Soares, Maria A A; Ribeiro, Regislane P; van den Hurk, Robert; Silva, José R V

2018-02-01

Infertility is the result of failure due to an organic disorder of the reproductive organs, especially their gametes. Recently, much progress has been made on generating germ cells, including oocytes, from various types of stem cells. This review focuses on advances in female germ cell differentiation from different kinds of stem cells, with emphasis on embryonic stem cells, adult stem cells, and induced pluripotent stem cells. The advantages and disadvantages of the derivation of female germ cells from several types of stem cells are also highlighted, as well as the ability of stem cells to generate mature and functional female gametes. This review shows that stem cell therapies have opened new frontiers in medicine, especially in the reproductive area, with the possibility of regenerating fertility.

Reduced hematopoietic stem cell frequency predicts outcome in acute myeloid leukemia.

PubMed

Wang, Wenwen; Stiehl, Thomas; Raffel, Simon; Hoang, Van T; Hoffmann, Isabel; Poisa-Beiro, Laura; Saeed, Borhan R; Blume, Rachel; Manta, Linda; Eckstein, Volker; Bochtler, Tilmann; Wuchter, Patrick; Essers, Marieke; Jauch, Anna; Trumpp, Andreas; Marciniak-Czochra, Anna; Ho, Anthony D; Lutz, Christoph

2017-09-01

In patients with acute myeloid leukemia and low percentages of aldehyde-dehydrogenase-positive cells, non-leukemic hematopoietic stem cells can be separated from leukemic cells. By relating hematopoietic stem cell frequencies to outcome we detected poor overall- and disease-free survival of patients with low hematopoietic stem cell frequencies. Serial analysis of matched diagnostic and follow-up samples further demonstrated that hematopoietic stem cells increased after chemotherapy in patients who achieved durable remissions. However, in patients who eventually relapsed, hematopoietic stem cell numbers decreased dramatically at the time of molecular relapse demonstrating that hematopoietic stem cell levels represent an indirect marker of minimal residual disease, which heralds leukemic relapse. Upon transplantation in immune-deficient mice cases with low percentages of hematopoietic stem cells of our cohort gave rise to leukemic or no engraftment, whereas cases with normal hematopoietic stem cell levels mostly resulted in multi-lineage engraftment. Based on our experimental data, we propose that leukemic stem cells have increased niche affinity in cases with low percentages of hematopoietic stem cells. To validate this hypothesis, we developed new mathematical models describing the dynamics of healthy and leukemic cells under different regulatory scenarios. These models suggest that the mechanism leading to decreases in hematopoietic stem cell frequencies before leukemic relapse must be based on expansion of leukemic stem cells with high niche affinity and the ability to dislodge hematopoietic stem cells. Thus, our data suggest that decreasing numbers of hematopoietic stem cells indicate leukemic stem cell persistence and the emergence of leukemic relapse. Copyright© 2017 Ferrata Storti Foundation.

Evaluation of the secretion and release of vascular endothelial growth factor from two-dimensional culture and three-dimensional cell spheroids formed with stem cells and osteoprecursor cells.

PubMed

Lee, Hyunjin; Lee, Sung-Il; Ko, Youngkyung; Park, Jun-Beom

2018-05-18

Co-culture has been applied in cell therapy, including stem cells, and has been reported to give enhanced functionality. In this study, stem-cell spheroids were formed in concave micromolds at different ratios of stem cells to osteoprecursor cells, and the amount of secretion of vascular endothelial growth factor (VEGF) was evaluated. Gingiva-derived stem cells and osteoprecursor cells in the amount of 6 × 105 were seeded on a 24-well culture plate or concave micromolds. The ratios of stem cells to osteoprecursor cells included: 0:4 (group 1), 1:3 (group 2), 2:2 (group 3), 3:1 (group 4), and 4:0 (group 5). The morphology of cells in a 2-dimensional culture (groups 1-5) showed a fibroblast-like appearance. The secretion of VEGF increased with the increase in stem cells, and a statistically significant increase was noted in groups 3, 4 and 5 when compared with the media-only group (p < 0.05). Osteoprecursor cells formed spheroids in concave microwells, and no noticeable change in the morphology was noted with the increase in stem cells. Spheroids containing stem cells were positive for the stem-cell markers SSEA-4. The secretion of VEGF from cell spheroids increased with the increase in stem cells. This study showed that cell spheroids formed with stem cells and osteoprecursor cells with different ratios, using microwells, had paracrine effects on the stem cells. The secretion of VEGF increased with the increase in stem cells. This stem-cell spheroid may be applied for tissue-engineering purposes.

The Role of Stem Cells in Aesthetic Surgery: Fact or Fiction?

PubMed Central

McArdle, Adrian; Senarath-Yapa, Kshemendra; Walmsley, Graham G.; Hu, Michael; Atashroo, David A.; Tevlin, Ruth; Zielins, Elizabeth; Gurtner, Geoffrey C.; Wan, Derrick C.; Longaker, Michael T.

2014-01-01

Stem cells are attractive candidates for the development of novel therapies, targeting indications that involve functional restoration of defective tissue. Although most stem cell therapies are new and highly experimental, there are clinics around the world that exploit vulnerable patients with the hope of offering supposed stem cell therapies, many of which operate without credible scientific merit, oversight, or other patient protection. We review the potential, as well as drawbacks, for incorporation of stem cells in cosmetic procedures. A review of FDA-approved indications and ongoing clinical trials with adipose stem cells is provided. Furthermore, a “snapshot” analysis of websites using the search terms “stem cell therapy” or “stem cell treatment” or “stem cell facelift” was performed. Despite the protective net cast by regulatory agencies such as the FDA and professional societies such as the American Society of Plastic Surgeons, we are witnessing worrying advertisements for procedures such as stem cell facelifts, stem cell breast augmentations, and even stem cell vaginal rejuvenation. The marketing and promotion of stem cell procedures in aesthetic surgery is not adequately supported by clinical evidence in the majority of cases. Stem cells offer tremendous potential, but the marketplace is saturated with unsubstantiated and sometimes fraudulent claims that may place patients at risk. With plastic surgeons at the forefront of stem cell-based regenerative medicine, it is critically important that we provide an example of a rigorous approach to research, data collection, and advertising of stem cell therapies. PMID:24732654

Cyst fluid analysis in the differential diagnosis of pancreatic cystic lesions: a pooled analysis.

PubMed

van der Waaij, Laurens A; van Dullemen, Hendrik M; Porte, Robert J

2005-09-01

Pancreatic cystic tumors commonly include serous cystadenoma (SCA), mucinous cystadenoma (MCA), and mucinous cystadenocarcinoma (MCAC). A differential diagnosis with pseudocysts (PC) can be difficult. Radiologic criteria are not reliable. The objective of the study is to investigate the value of cyst fluid analysis in the differential diagnosis of benign (SCA, PC) vs. premalignant or malignant (MCA, MCAC) lesions. A search in PubMed was performed with the search terms cyst, pancrea, and fluid. Articles about cyst fluid analysis of pancreatic lesions that contained the individual data of at least 7 patients were included in the study. Data of all individual patients were combined and were plotted in scatter grams. Cutoff levels were determined. Twelve studies were included, which comprised data of 450 patients. Cysts with an amylase concentration <250 U/L were SCA, MCA, or MCAC (sensitivity 44%, specificity 98%) and, thus, virtually excluded PC. A carcinoembryonic antigen (CEA) <5 ng/mL suggested a SCA or PC (sensitivity 50%, specificity 95%). A CEA >800 ng/mL strongly suggested MCA or MCAC (sensitivity 48%, specificity 98%). A carbohydrate-associated antigen (CA) 19-9 <37 U/mL strongly suggested PC or SCA (sensitivity 19%, specificity 98%). Cytologic examination revealed malignant cells in 48% of MCAC (n = 111). Most pancreatic cystic tumors should be resected without the need for cyst fluid analysis. However, in asymptomatic patients, in patients with an increased surgical risk, and, in patients in whom there is a diagnostic uncertainty about the presence of a PC, cyst fluid analysis helps to determine the optimal therapeutic strategy.

An Alexandrium Spp. Cyst Record from Sequim Bay, Washington State, USA, and its Relation to Past Climate Variability(1).

PubMed

Feifel, Kirsten M; Moore, Stephanie K; Horner, Rita A

2012-06-01

Since the 1970s, Puget Sound, Washington State, USA, has experienced an increase in detections of paralytic shellfish toxins (PSTs) in shellfish due to blooms of the harmful dinoflagellate Alexandrium. Natural patterns of climate variability, such as the Pacific Decadal Oscillation (PDO), and changes in local environmental factors, such as sea surface temperature (SST) and air temperature, have been linked to the observed increase in PSTs. However, the lack of observations of PSTs in shellfish prior to the 1950s has inhibited statistical assessments of longer-term trends in climate and environmental conditions on Alexandrium blooms. After a bloom, Alexandrium cells can enter a dormant cyst stage, which settles on the seafloor and then becomes entrained into the sedimentary record. In this study, we created a record of Alexandrium spp. cysts from a sediment core obtained from Sequim Bay, Puget Sound. Cyst abundances ranged from 0 to 400 cysts · cm(-3) and were detected down-core to a depth of 100 cm, indicating that Alexandrium has been present in Sequim Bay since at least the late 1800s. The cyst record allowed us to statistically examine relationships with available environmental parameters over the past century. Local air temperature and sea surface temperature were positively and significantly correlated with cyst abundances from the late 1800s to 2005; no significant relationship was found between PDO and cyst abundances. This finding suggests that local environmental variations more strongly influence Alexandrium population dynamics in Puget Sound when compared to large-scale changes. © 2012 Phycological Society of America.

Mesothelial Cysts of the Round Ligament of the Uterus in 9 Patients: a 15-year experience.

PubMed

Tirnaksiz, Mehmet; Erkan, Arman; Dogrul, Ahmet Bulent; Abbasoglu, Osman

2016-04-04

Aim of this study was to evaluate the characteristic features of patients with mesothelial cyst of the round ligament of the uterus and the incidence of this entity. This was a retrospective review of 3065 patients who underwent inguinal exploration for groin mass from 1998 to 2013. Clinical, radiological and histopathological features of patients with a diagnosis of mesothelial cyst of the round ligament were analyzed. Of the 405 female patients reviewed 9 mesothelial cysts of the round ligament were identified (2.2%). The median age was 37 (range 19-82 years). In all patients the groin mass was manually irreducible on physical examination. The lesions were on the right side in 6 (66.6%) patients. These were identified before surgery in 4 (all by groin ultrasonography). Three were misidentified as a hernia before surgery. The remaining 2 (22%) had both hernia and the mesothelial cyst of the round ligament. The cysts were identified after surgery at the time of histopathological examination in these two patients. In all patients histopathological examination revealed multilobular cystic lesion lined by a single layer of mesothelial cells. Cystic lesions arising from the round ligament were identified and excised along with the round ligament in 7 patients. In the remaining 2, a hernia repair was also performed. There was no recurrence at follow-up. Mesothelial cysts of the round ligament are rare. They are easily misidentified as groin hernia. An accurate diagnosis requires a high index of suspicion and is greatly aided by preoperative imaging studies.

Adhesive arachnoiditis after percutaneous fibrin glue treatment of a sacral meningeal cyst.

PubMed

Hayashi, Kazunori; Nagano, Junji; Hattori, Satoshi

2014-06-01

The authors present the case of a 64-year-old woman who was referred for severe sacral pain. She reported that her pain had been longstanding, and had greatly increased after percutaneous fibrin glue placement therapy for a sacral meningeal cyst 2 months earlier at a different hospital. An MRI scan obtained immediately after fibrin glue placement at that hospital suggested that fibrin glue had migrated superiorly into the subarachnoid space from the sacral cyst to the level of L-4. On admission to the authors' institution, physical examination demonstrated no abnormal findings except for perianal hypesthesia. An MRI study obtained at admission demonstrated a cystic lesion in the peridural space from the level of S-2 to S-4. Inhomogeneous intensity was identified in this region on T2-weighted images. Because the cauda equina and nerve roots appeared to be compressed by the lesion, total cyst excision was performed. The cyst cavity was filled with fluid that resembled CSF, plus gelatinous material. Histopathological examination revealed that the cyst wall was composed of hyaline connective tissue with some calcification. No nervous tissue or ganglion cells were found in the tissue. The gelatinous material was acellular, and appeared to be degenerated fibrin glue. Sacral pain persisted to some extent after surgery. The authors presumed that migrated fibrin glue caused the development of adhesive arachnoiditis. The risk of adhesive arachnoiditis should be considered when this therapy is planned. Communication between a cyst and the subarachnoid space should be confirmed to be sufficiently narrow to prevent the migration of injected fibrin glue.

A WUSCHEL-Independent Stem Cell Specification Pathway Is Repressed by PHB, PHV and CNA in Arabidopsis.

PubMed

Lee, Chunghee; Clark, Steven E

2015-01-01

The homeostatic maintenance of stem cells that carry out continuous organogenesis at the shoot meristem is crucial for plant development. Key known factors act to signal between the stem cells and an underlying group of cells thought to act as the stem cell niche. In Arabidopsis thaliana the homeodomain transcription factor WUSCHEL (WUS) is essential for stem cell initiation and maintenance at shoot and flower meristems. Recent data suggest that the WUS protein may move from the niche cells directly into the stem cells to maintain stem cell identity. Here we provide evidence for a second, previously unknown, pathway for stem cell specification at shoot and flower meristems that bypasses the requirement for WUS. We demonstrate that this novel stem cell specification pathway is normally repressed by the activity of the HD-zip III transcription factors PHABULOSA (PHB), PHAVOLUTA (PHV) and CORONA (CNA). When de-repressed, this second stem cell pathway leads to an accumulation of stem cells and an enlargement of the stem cell niche. When de-repressed in a wus mutant background, this second stem cell pathway leads to functional meristems with largely normal cell layering and meristem morphology, activation of WUS cis regulatory elements, and extensive, but not indeterminate, organogenesis. Thus, WUS is largely dispensable for stem cell specification and meristem function, suggesting a set of key stem cell specification factors, competitively regulated by WUS and PHB/PHV/CNA, remain unidentified.

A WUSCHEL-Independent Stem Cell Specification Pathway Is Repressed by PHB, PHV and CNA in Arabidopsis

PubMed Central

Lee, Chunghee; Clark, Steven E.

2015-01-01

The homeostatic maintenance of stem cells that carry out continuous organogenesis at the shoot meristem is crucial for plant development. Key known factors act to signal between the stem cells and an underlying group of cells thought to act as the stem cell niche. In Arabidopsis thaliana the homeodomain transcription factor WUSCHEL (WUS) is essential for stem cell initiation and maintenance at shoot and flower meristems. Recent data suggest that the WUS protein may move from the niche cells directly into the stem cells to maintain stem cell identity. Here we provide evidence for a second, previously unknown, pathway for stem cell specification at shoot and flower meristems that bypasses the requirement for WUS. We demonstrate that this novel stem cell specification pathway is normally repressed by the activity of the HD-zip III transcription factors PHABULOSA (PHB), PHAVOLUTA (PHV) and CORONA (CNA). When de-repressed, this second stem cell pathway leads to an accumulation of stem cells and an enlargement of the stem cell niche. When de-repressed in a wus mutant background, this second stem cell pathway leads to functional meristems with largely normal cell layering and meristem morphology, activation of WUS cis regulatory elements, and extensive, but not indeterminate, organogenesis. Thus, WUS is largely dispensable for stem cell specification and meristem function, suggesting a set of key stem cell specification factors, competitively regulated by WUS and PHB/PHV/CNA, remain unidentified. PMID:26011610

Generation, characterization and potential therapeutic applications of mature and functional hepatocytes from stem cells.

PubMed

Zhang, Zhenzhen; Liu, Jianfang; Liu, Yang; Li, Zheng; Gao, Wei-Qiang; He, Zuping

2013-02-01

Liver cancer is the sixth most common tumor in the world and the majority of patients with this disease usually die within 1 year. The effective treatment for end-stage liver disease (also known as liver failure), including liver cancer or cirrhosis, is liver transplantation. However, there is a severe shortage of liver donors worldwide, which is the major handicap for the treatment of patients with liver failure. Scarcity of liver donors underscores the urgent need of using stem cell therapy to the end-stage liver disease. Notably, hepatocytes have recently been generated from hepatic and extra-hepatic stem cells. We have obtained mature and functional hepatocytes from rat hepatic stem cells. Here, we review the advancements on hepatic differentiation from various stem cells, including hepatic stem cells, embryonic stem cells, the induced pluripotent stem cells, hematopoietic stem cells, mesenchymal stem cells, and probably spermatogonial stem cells. The advantages, disadvantages, and concerns on differentiation of these stem cells into hepatic cells are highlighted. We further address the methodologies, phenotypes, and functional characterization on the differentiation of numerous stem cells into hepatic cells. Differentiation of stem cells into mature and functional hepatocytes, especially from an extra-hepatic stem cell source, would circumvent the scarcity of liver donors and human hepatocytes, and most importantly it would offer an ideal and promising source of hepatocytes for cell therapy and tissue engineering in treating liver disease. Copyright © 2012 Wiley Periodicals, Inc.

Transfundal puncture of a large ovarian cyst with hysteroscopic and ultrasonographic guidance.

PubMed

Zolnierczyk, Piotr; Cendrowski, Krzysztof; Sawicki, Wlodzimierz

2015-01-01

This paper describes the case of an 83-year-old patient with hypertension, diabetes, obesity (body mass index - 38), congestive heart failure, and history of cardiac surgery, who was referred for a diagnostic-therapeutic decompression of a large, symptomatic ovarian cyst. Due to anatomical conditions, the only safe way was a transfundal puncture under mini-hysteroscopic and ultrasound guidance. A puncture with aspiration of 300 mL of serous fluid from the cyst was performed without technical problems and complications. Cytology showed no cancer cells in the examined liquid. Relief from pain and compression discomfort was achieved in the patient. This case shows the possibility of combining ultrasound and minimally invasive diagnostic methods like hysteroscopy in selected clinical situations.

Transfundal puncture of a large ovarian cyst with hysteroscopic and ultrasonographic guidance

PubMed Central

Zolnierczyk, Piotr; Cendrowski, Krzysztof; Sawicki, Wlodzimierz

2015-01-01

This paper describes the case of an 83-year-old patient with hypertension, diabetes, obesity (body mass index – 38), congestive heart failure, and history of cardiac surgery, who was referred for a diagnostic–therapeutic decompression of a large, symptomatic ovarian cyst. Due to anatomical conditions, the only safe way was a transfundal puncture under mini-hysteroscopic and ultrasound guidance. A puncture with aspiration of 300 mL of serous fluid from the cyst was performed without technical problems and complications. Cytology showed no cancer cells in the examined liquid. Relief from pain and compression discomfort was achieved in the patient. This case shows the possibility of combining ultrasound and minimally invasive diagnostic methods like hysteroscopy in selected clinical situations. PMID:25999768

Superficial Enhanced Fluid Fat Injection (SEFFI) to Correct Volume Defects and Skin Aging of the Face and Periocular Region.

PubMed

Bernardini, Francesco P; Gennai, Alessandro; Izzo, Luigi; Zambelli, Alessandra; Repaci, Erica; Baldelli, Ilaria; Fraternali-Orcioni, G; Hartstein, Morris E; Santi, Pier Luigi; Quarto, Rodolfo

2015-07-01

Although recent research on micro fat has shown the potential advantages of superficial implantation and high stem cell content, clinical applications thus far have been limited. The authors report their experience with superficial enhanced fluid fat injection (SEFFI) for the correction of volume loss and skin aging of the face in general and in the periocular region. The finer SEFFI preparation (0.5 mL) was injected into the orbicularis in the periorbital and perioral areas, and the 0.8-mL preparation was injected subdermally elsewhere in the face. The records of 98 consecutive patients were reviewed. Average follow-up time was 6 months, and average volume of implanted fat was 20 mL and 51.4 mL for the 0.5-mL and 0.8-mL preparations, respectively. Good or excellent results were achieved for volume restoration and skin improvement in all patients. Complications were minor and included an oil cyst in 3 patients. The smaller SEFFI quantity (0.5 mL) was well suited to correct volume loss in the eyelids, especially the deep upper sulcus and tear trough, whereas the larger SEFFI content was effective for larger volume deficits in other areas of the face, including the brow, temporal fossa, zygomatic-malar region, nasolabial folds, marionette lines, chin, and lips. The fat administered by SEFFI is easily harvested via small side-port cannulae, yielding micro fat that is rich in viable adipocytes and stem cells. Both volumes of fat (0.5 mL and 0.8 mL) were effective for treating age-related lipoatrophy, reducing facial rhytids, and improving skin quality. 4 Therapeutic. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Stem cells in dentistry--part I: stem cell sources.

PubMed

Egusa, Hiroshi; Sonoyama, Wataru; Nishimura, Masahiro; Atsuta, Ikiru; Akiyama, Kentaro

2012-07-01

Stem cells can self-renew and produce different cell types, thus providing new strategies to regenerate missing tissues and treat diseases. In the field of dentistry, adult mesenchymal stem/stromal cells (MSCs) have been identified in several oral and maxillofacial tissues, which suggests that the oral tissues are a rich source of stem cells, and oral stem and mucosal cells are expected to provide an ideal source for genetically reprogrammed cells such as induced pluripotent stem (iPS) cells. Furthermore, oral tissues are expected to be not only a source but also a therapeutic target for stem cells, as stem cell and tissue engineering therapies in dentistry continue to attract increasing clinical interest. Part I of this review outlines various types of intra- and extra-oral tissue-derived stem cells with regard to clinical availability and applications in dentistry. Additionally, appropriate sources of stem cells for regenerative dentistry are discussed with regard to differentiation capacity, accessibility and possible immunomodulatory properties. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Plant stem cell niches.

PubMed

Stahl, Yvonne; Simon, Rüdiger

2005-01-01

Stem cells are required to support the indeterminate growth style of plants. Meristems are a plants stem cell niches that foster stem cell survival and the production of descendants destined for differentiation. In shoot meristems, stem cell fate is decided at the populational level. The size of the stem cell domain at the meristem tip depends on signals that are exchanged with cells of the organizing centre underneath. In root meristems, individual stem cells are controlled by direct interaction with cells of the quiescent centre that lie in the immediate neighbourhood. Analysis of the interactions and signaling processes in the stem cell niches has delivered some insights into the molecules that are involved and revealed that the two major niches for plant stem cells are more similar than anticipated.

CD74 in Kidney Disease

PubMed Central

Valiño-Rivas, Lara; Baeza-Bermejillo, Ciro; Gonzalez-Lafuente, Laura; Sanz, Ana Belen; Ortiz, Alberto; Sanchez-Niño, Maria Dolores

2015-01-01

CD74 (invariant MHC class II) regulates protein trafficking and is a receptor for macrophage migration inhibitory factor (MIF) and d-dopachrome tautomerase (d-DT/MIF-2). CD74 expression is increased in tubular cells and/or glomerular podocytes and parietal cells in human metabolic nephropathies, polycystic kidney disease, graft rejection and kidney cancer and in experimental diabetic nephropathy and glomerulonephritis. Stressors like abnormal metabolite (glucose, lyso-Gb3) levels and inflammatory cytokines increase kidney cell CD74. MIF activates CD74 to increase inflammatory cytokines in podocytes and tubular cells and proliferation in glomerular parietal epithelial cells and cyst cells. MIF overexpression promotes while MIF targeting protects from experimental glomerular injury and kidney cysts, and interference with MIF/CD74 signaling or CD74 deficiency protected from crescentic glomerulonephritis. However, CD74 may protect from interstitial kidney fibrosis. Furthermore, CD74 expression by stressed kidney cells raises questions about the kidney safety of cancer therapy strategies delivering lethal immunoconjugates to CD74-expressing cells. Thus, understanding CD74 biology in kidney cells is relevant for kidney therapeutics. PMID:26441987

Stem cells in the Drosophila digestive system.

PubMed

Zeng, Xiankun; Chauhan, Chhavi; Hou, Steven X

2013-01-01

Adult stem cells maintain tissue homeostasis by continuously replenishing damaged, aged and dead cells in any organism. Five types of region and organ-specific multipotent adult stem cells have been identified in the Drosophila digestive system: intestinal stem cells (ISCs) in the posterior midgut; hindgut intestinal stem cells (HISCs) at the midgut/hindgut junction; renal and nephric stem cells (RNSCs) in the Malpighian Tubules; type I gastric stem cells (GaSCs) at foregut/midgut junction; and type II gastric stem cells (GSSCs) at the middle of the midgut. Despite the fact that each type of stem cell is unique to a particular organ, they share common molecular markers and some regulatory signaling pathways. Due to the simpler tissue structure, ease of performing genetic analysis, and availability of abundant mutants, Drosophila serves as an elegant and powerful model system to study complex stem cell biology. The recent discoveries, particularly in the Drosophila ISC system, have greatly advanced our understanding of stem cell self-renewal, differentiation, and the role of stem cells play in tissue homeostasis/regeneration and adaptive tissue growth.

Induced cancer stem cells generated by radiochemotherapy and their therapeutic implications.

PubMed

Chen, Xiewan; Liao, Rongxia; Li, Dezhi; Sun, Jianguo

2017-03-07

Local and distant recurrence of malignant tumors following radio- and/or chemotherapy correlates with poor prognosis of patients. Among the reasons for cancer recurrence, preexisting cancer stem cells (CSCs) are considered the most likely cause due to their properties of self-renewal, pluripotency, plasticity and tumorigenicity. It has been demonstrated that preexisting cancer stem cells derive from normal stem cells and differentiated somatic cells that undergo transformation and dedifferentiation respectively under certain conditions. However, recent studies have revealed that cancer stem cells can also be induced from non-stem cancer cells by radiochemotherapy, constituting the subpopulation of induced cancer stem cells (iCSCs). These findings suggest that radiochemotherapy has the side effect of directly transforming non-stem cancer cells into induced cancer stem cells, possibly contributing to tumor recurrence and metastasis. Therefore, drugs targeting cancer stem cells or preventing dedifferentiation of non-stem cancer cells can be combined with radiochemotherapy to improve its antitumor efficacy. The current review is to investigate the mechanisms by which induced cancer stem cells are generated by radiochemotherapy and hence provide new strategies for cancer treatment.

Stem cells in gastroenterology and hepatology

PubMed Central

Quante, Michael; Wang, Timothy C.

2010-01-01

Cellular and tissue regeneration in the gastrointestinal tract and liver depends on stem cells with properties of longevity, self-renewal and multipotency. Progress in stem cell research and the identification of potential esophageal, gastric, intestinal, colonic, hepatic and pancreatic stem cells provides hope for the use of stem cells in regenerative medicine and treatments for disease. Embryonic stem cells and induced pluripotent stem cells have the potential to give rise to any cell type in the human body, but their therapeutic application remains challenging. The use of adult or tissue-restricted stem cells is emerging as another possible approach for the treatment of gastrointestinal diseases. The same self-renewal properties that allow stem cells to remain immortal and generate any tissue can occasionally make their proliferation difficult to control and make them susceptible to malignant transformation. This Review provides an overview of the different types of stem cell, focusing on tissue-restricted adult stem cells in the fields of gastroenterology and hepatology and summarizing the potential benefits and risks of using stems cells to treat gastroenterological and liver disorders. PMID:19884893

Lower Oncogenic Potential of Human Mesenchymal Stem Cells Derived from Cord Blood Compared to Induced Pluripotent Stem Cells

PubMed Central

Foroutan, T.; Najmi, M.; Kazemi, N.; Hasanlou, M.; Pedram, A.

2015-01-01

Background: In regenerative medicine, use of each of the mesenchymal stem cells derived from bone marrow, cord blood, and adipose tissue, has several cons and pros. Mesenchymal stem cells derived from cord blood have been considered the best source for precursor transplantation. Direct reprogramming of a somatic cell into induced pluripotent stem cells by over-expression of 6 transcription factors Oct4, Sox2, Klf4, lin28, Nanog, and c-Myc has great potential for regenerative medicine, eliminating the ethical issues of embryonic stem cells and the rejection problems of using non-autologous cells. Objective: To compare reprogramming and pluripotent markers OCT4, Sox-2, c-Myc, Klf4, Nanog, and lin28 in mesenchymal stem cells derived from cord blood and induced pluripotent stem cells. Methods: We analyzed the expression level of OCT4, Sox-2, c-Myc, Klf4, Nanog and lin28 genes in human mesenchymal stem cells derived from cord blood and induced pluripotent stem cells by cell culture and RT-PCR. Results: The expression level of pluripotent genes OCT4 and Sox-2, Nanog and lin28 in mesenchymal stem cells derived from cord blood were significantly higher than those in induced pluripotent stem cells. In contrast to OCT-4A and Sox-2, Nanog and lin28, the expression level of oncogenic factors c-Myc and Klf4 were significantly higher in induced pluripotent stem cells than in mesenchymal stem cells derived from cord blood. Conclusion: It could be concluded that mesenchymal stem cells derived from human cord blood have lower oncogenic potential compared to induced pluripotent stem cells. PMID:26306155

Eckol suppresses maintenance of stemness and malignancies in glioma stem-like cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyun, Kyung-Hwan; Yoon, Chang-Hwan; Kim, Rae-Kwon

A subpopulation of cancer cells with stem cell properties is responsible for tumor maintenance and progression, and may contribute to resistance to anticancer treatments. Thus, compounds that target cancer stem-like cells could be usefully applied to destroy cancer. In this study, we investigated the effect of Eckol, a phlorotannin compound, on stemness and malignancies in glioma stem-like cells. To determine whether Eckol targets glioma stem-like cells, we examined whether Eckol treatment could change the expression levels of glioma stem-like cell markers and self-renewal-related proteins as well as the sphere forming ability, and the sensitivity to anticancer treatments. Alterations in themore » malignant properties of sphere-derived cells by Eckol were also investigated by soft-agar colony forming assay, by xenograft assay in nude mice, and by cell invasion assay. Treatment of sphere-forming glioma cells with Eckol effectively decreased the sphere formation as well as the CD133{sup +} cell population. Eckol treatment suppressed expression of the glioma stem-like cell markers and the self-renewal-related proteins without cell death. Moreover, treatment of glioma stem-like cells with Eckol significantly attenuated anchorage-independent growth on soft agar and tumor formation in xenograft mice. Importantly, Eckol treatment effectively reduced the resistance of glioma stem-like cells to ionizing radiation and temozolomide. Treatment of glioma stem-like cells with Eckol markedly blocked both phosphoinositide 3-kinase-Akt and Ras-Raf-1-Erk signaling pathways. These results indicate that the natural phlorotannin Eckol suppresses stemness and malignancies in glioma stem-like cells, and thereby makes glioma stem-like cells more sensitive to anticancer treatments, providing novel therapeutic strategies targeting specifically cancer stem-like cells.« less

Flagellin preconditioning enhances the efficacy of mesenchymal stem cells in an irradiation-induced proctitis model.

PubMed

Linard, Christine; Strup-Perrot, Carine; Lacave-Lapalun, Jean-Victor; Benderitter, Marc

2016-09-01

The success of mesenchymal stem cell transplantation for proctitis depends not only on cell donors but also on host microenvironmental factors, which play a major role in conditioning mesenchymal stem cell immunosuppressive action and repair. This study sought to determine if flagellin, a TLR5 ligand, can enhance the mesenchymal stem cell treatment efficacy in radiation-induced proctitis. With the use of a colorectal model of 27 Gy irradiation in rats, we investigated and compared the effects on immune capacity and remodeling at 28 d after irradiation of the following: 1) systemic mesenchymal stem cell (5 × 10(6)) administration at d 7 after irradiation, 2) administration of flagellin at d 3 and systemic mesenchymal stem cell administration at d 7, and 3) in vitro preconditioning of mesenchymal stem cells with flagellin, 24 h before their administration on d 7. The mucosal CD8(+) T cell population was normalized after treatment with flagellin-preconditioned mesenchymal stem cells or flagellin plus mesenchymal stem cells, whereas mesenchymal stem cells alone did not alter the radiation-induced elevation of CD8(+) T cell frequency. Mesenchymal stem cell treatment returned the irradiation-elevated frequency of CD25(+) cells in the mucosa-to-control levels, whereas both flagellin-preconditioned mesenchymal stem cell and flagellin-plus-mesenchymal stem cell treatment each significantly increased not only CD25(+) cell frequency but also forkhead box p3 and IL-2Rα expression. Specifically, IL-10 was overexpressed after flagellin-preconditioned mesenchymal stem cell treatment. Analysis of collagen expression showed that the collagen type 1/collagen type 3 ratio, an indicator of wound-healing maturation, was low in the irradiated and mesenchymal stem cell-treated groups and returned to the normal level only after the flagellin-preconditioned mesenchymal stem cell treatment. This was associated with a reduction in myofibroblast accumulation. In a proctitis model, flagellin-preconditioned mesenchymal stem cells improved colonic immune capacity and enhanced tissue remodeling. © Society for Leukocyte Biology.

Acute Exposure of Medaka to Carcinogens: An Ultrastructural, Cytochemical and Morphometric Analysis of Liver and Kidney.

DTIC Science & Technology

1992-02-24

specific indicators of cytotoxicity. Livers from three fish were distinguished by the presence of multilocular cyst -like lesions that resemble...plankton 4 times a week and brine shrimp 3 days a week. Nematodes were also a component of the diet with the amount given dependent upon the age of... cyst -like lesions termed spongiosis hepatis. The structural framework of the spongiotic lesions was formed by attenuated cells with small irregular

Effects of pH, sodium chloride, and curing salt on the infectivity of Toxoplasma gondii tissue cysts.

PubMed

Pott, S; Koethe, M; Bangoura, B; Zöller, B; Daugschies, A; Straubinger, R K; Fehlhaber, K; Ludewig, M

2013-06-01

Toxoplasma gondii is one of the most common zoonotic parasites in the world. The parasite causes no or mild symptoms in immunocompetent humans. However, a high potential hazard exists for seronegative pregnant women and immunocompromised patients. The consumption of meat containing tissue cysts or oocyst-contaminated vegetables and fruits or the handling of cat feces poses a high risk of infection with T. gondii. It is known that raw minced meat, raw fresh sausages, and locally produced raw meat products are possible causes of T. gondii infection. The infectivity of T. gondii tissue cysts in meat products depends, among other factors, on the pH and the salt concentration. Therefore, the impact of these two factors on the tissue cysts was examined. For this purpose, dissected musculature and brain from experimentally infected mice (donor mice) were placed in a cell culture medium (RPMI 1640). The medium was adjusted to different pH values (pH 5, 6, and 7) with lactic acid and to different salt concentrations (2.0, 2.5, and 3.0%) with sodium chloride (NaCl) or nitrite-enriched curing salt (NCS) for the various tests. After storage at 4°C for different time periods, the materials were fed to bioassay mice. Later, the brains were examined for presence of T. gondii to assess the infectivity. The data show that T. gondii tissue cysts have a high pH tolerance. Cysts were infectious in the muscle for up to 26 days (pH 5). In contrast to their tolerance to pH, cysts were very sensitive to salt. Muscle cysts survived at an NaCl concentration of up to 2.0% only, and for no longer than 8 days. At NaCl concentrations of 2.5 and 3.0%, the cysts lost their infectivity after 1 day. When NCS instead of NaCl was used under the same conditions, T. gondii muscle cysts retained infectivity for only 4 days at 2.0%. Consequently, NCS (NaCl plus 0.5% nitrite) has a stronger effect on T. gondii cysts than does common table salt. Sausages produced with low NaCl concentration and short contact times pose a potential risk for susceptible individuals.

Disruption of IFT Complex A Causes Cystic Kidneys without Mitotic Spindle Misorientation

PubMed Central

Jonassen, Julie A.; SanAgustin, Jovenal; Baker, Stephen P.

2012-01-01

Intraflagellar transport (IFT) complexes A and B build and maintain primary cilia. In the mouse, kidney-specific or hypomorphic mutant alleles of IFT complex B genes cause polycystic kidneys, but the influence of IFT complex A proteins on renal development is not well understood. In the present study, we found that HoxB7-Cre–driven deletion of the complex A gene Ift140 from collecting ducts disrupted, but did not completely prevent, cilia assembly. Mutant kidneys developed collecting duct cysts by postnatal day 5, with rapid cystic expansion and renal dysfunction by day 15 and little remaining parenchymal tissue by day 20. In contrast to many models of polycystic kidney disease, precystic Ift140-deleted collecting ducts showed normal centrosomal positioning and no misorientation of the mitotic spindle axis, suggesting that disruption of oriented cell division is not a prerequisite to cyst formation in these kidneys. Precystic collecting ducts had an increased mitotic index, suggesting that cell proliferation may drive cyst expansion even with normal orientation of the mitotic spindle. In addition, we observed significant increases in expression of canonical Wnt pathway genes and mediators of Hedgehog and tissue fibrosis in highly cystic, but not precystic, kidneys. Taken together, these studies indicate that loss of Ift140 causes pronounced renal cystic disease and suggest that abnormalities in several different pathways may influence cyst progression. PMID:22282595

Epidermal stem cells: location, potential and contribution to cancer.

PubMed

Ambler, C A; Määttä, A

2009-01-01

Epidermal stem cells have been classically characterized as slow-cycling, long-lived cells that reside in discrete niches in the skin. Gene expression studies of niche-resident cells have revealed a number of stem cell markers and regulators, including the Wnt/beta-catenin, Notch, p63, c-Myc and Hedgehog pathways. A new study challenges the traditional developmental paradigm of slow-cycling stem cells and rapid-cycling transit amplifying cells in some epidermal regions, and there is mounting evidence to suggest that multi-lineage epidermal progenitors can be isolated from highly proliferative, non-niche regions. Whether there is a unique microenvironment surrounding these progenitors remains to be determined. Interestingly, cancer stem cells derived from epidermal tumours exist independent of the classic skin stem cell niche, yet also have stem cell properties, including multi-lineage differentiation. This review summarizes recent studies identifying the location and regulators of mouse and human epidermal stem cells and highlights the strategies used to identify cancer stem cells, including expression of normal epidermal stem cell markers, expression of cancer stem cell markers identified in other epidermal tumours and characterization of side-population tumour cells.

Macrophage depletion and Schwann cell transplantation reduce cyst size after rat contusive spinal cord injury.

PubMed

Lee, Yee-Shuan; Funk, Lucy H; Lee, Jae K; Bunge, Mary Bartlett

2018-04-01

Schwann cell transplantation is a promising therapy for the treatment of spinal cord injury (SCI) and is currently in clinical trials. In our continuing efforts to improve Schwann cell transplantation strategies, we sought to determine the combined effects of Schwann cell transplantation with macrophage depletion. Since macrophages are major inflammatory contributors to the acute spinal cord injury, and are the major phagocytic cells, we hypothesized that transplanting Schwann cells after macrophage depletion will improve cell survival and integration with host tissue after SCI. To test this hypothesis, rat models of contusive SCI at thoracic level 8 were randomly subjected to macrophage depletion or not. In rat subjected to macrophage depletion, liposomes filled with clodronate were intraperitoneally injected at 1, 3, 6, 11, and 18 days post injury. Rats not subjected to macrophage depletion were intraperitoneally injected with liposomes filled with phosphate buffered saline. Schwann cells were transplanted 1 week post injury in all rats. Biotinylated dextran amine (BDA) was injected at thoracic level 5 to evalute axon regeneration. The Basso, Beattie, and Bresnahan locomotor test, Gridwalk test, and sensory test using von Frey filaments were performed to assess functional recovery. Immunohistochemistry was used to detect glial fibrillary acidic protein, neurofilament, and green fluorescent protein (GFP), and also to visulize BDA-labelled axons. The GFP labeled Schwann cell and cyst and lesion volumes were quantified using stained slides. The numbers of BDA-positive axons were also quantified. At 8 weeks after Schwann cell transplantation, there was a significant reduction in cyst and lesion volumes in the combined treatment group compared to Schwann cell transplantation alone. These changes were not associated, however, with improved Schwann cell survival, axon growth, or locomotor recovery. Although combining Schwann cell transplantation with macrophage depletion does improve histopathology of the injury site, the effect on axon growth and behavioral recovery appears no better than what can be achieved with Schwann cell transplants alone.

Macrophage depletion and Schwann cell transplantation reduce cyst size after rat contusive spinal cord injury

PubMed Central

Lee, Yee-Shuan; Funk, Lucy H.; Lee, Jae K.; Bunge, Mary Bartlett

2018-01-01

Schwann cell transplantation is a promising therapy for the treatment of spinal cord injury (SCI) and is currently in clinical trials. In our continuing efforts to improve Schwann cell transplantation strategies, we sought to determine the combined effects of Schwann cell transplantation with macrophage depletion. Since macrophages are major inflammatory contributors to the acute spinal cord injury, and are the major phagocytic cells, we hypothesized that transplanting Schwann cells after macrophage depletion will improve cell survival and integration with host tissue after SCI. To test this hypothesis, rat models of contusive SCI at thoracic level 8 were randomly subjected to macrophage depletion or not. In rat subjected to macrophage depletion, liposomes filled with clodronate were intraperitoneally injected at 1, 3, 6, 11, and 18 days post injury. Rats not subjected to macrophage depletion were intraperitoneally injected with liposomes filled with phosphate buffered saline. Schwann cells were transplanted 1 week post injury in all rats. Biotinylated dextran amine (BDA) was injected at thoracic level 5 to evalute axon regeneration. The Basso, Beattie, and Bresnahan locomotor test, Gridwalk test, and sensory test using von Frey filaments were performed to assess functional recovery. Immunohistochemistry was used to detect glial fibrillary acidic protein, neurofilament, and green fluorescent protein (GFP), and also to visulize BDA-labelled axons. The GFP labeled Schwann cell and cyst and lesion volumes were quantified using stained slides. The numbers of BDA-positive axons were also quantified. At 8 weeks after Schwann cell transplantation, there was a significant reduction in cyst and lesion volumes in the combined treatment group compared to Schwann cell transplantation alone. These changes were not associated, however, with improved Schwann cell survival, axon growth, or locomotor recovery. Although combining Schwann cell transplantation with macrophage depletion does improve histopathology of the injury site, the effect on axon growth and behavioral recovery appears no better than what can be achieved with Schwann cell transplants alone. PMID:29722321

Metastatic squamous cell carcinoma of the gingiva appearing as a solitary branchial cyst carcinoma: diagnostic role of PET/CT.

PubMed

Zhang, Xiong-Xin; Zhao, Kui; Zhou, Shui-Hong; Wang, Qin-Ying; Liu, Jian-Hua; Lu, Zhong-Jie

2014-01-01

We herein present a case of a left cervical cystic mass, for which the initial pathological diagnosis was branchial cleft cyst carcinoma (following complete mass excision). Thorough postoperative examinations, including with FDG positron emission tomography/computed tomography (PET/CT), revealed a primary tumor in the retromolar region of the left mandible. A 52-year-old female presented with a 2-month history of a painless, progressively enlarged left-sided neck mass. Fine-needle aspiration biopsy suggested a branchial cleft cyst. Physical examination revealed a 3 × 3-cm smooth, tender mass in the upper-left neck and anterior border of the sternocleidomastoid muscle. Examination using nasendoscopy and a strobolaryngoscope revealed no abnormalities of the nasal cavity, nasopharynx, oropharynx, hypopharynx or larynx. MRI of the neck revealed a solitary, round, cystic mass under the left parotid gland. The mass was excised completely. Pathologic results indicated a branchial cleft cyst carcinoma. According to the diagnostic criteria for a branchial cleft cystic carcinoma, PET/CT was performed to detect the occult primary site. PET/CT revealed high FDG uptake in the tooth root of the left mandible. Frozen sections of the mass were indicative of moderate, differentiated squamous cell carcinoma. The carcinoma in the retromolar region of the left mandible was locally excised under general anesthesia. A partial left maxillectomy, partial mandibulectomy, and left radical neck dissection were performed. The patient received postoperative concurrent chemoradiotherapy, and was disease-free at the 8-month follow-up. True branchial cleft cyst carcinoma is rare: once diagnosed, it should be distinguished from metastatic cystic cervical lymph and occult primary carcinoma. FDG PET/CT is useful in the identification of occult primary tumor.

MicroRNAs: key regulators of stem cells.

PubMed

Gangaraju, Vamsi K; Lin, Haifan

2009-02-01

The hallmark of a stem cell is its ability to self-renew and to produce numerous differentiated cells. This unique property is controlled by dynamic interplays between extrinsic signalling, epigenetic, transcriptional and post-transcriptional regulations. Recent research indicates that microRNAs (miRNAs) have an important role in regulating stem cell self-renewal and differentiation by repressing the translation of selected mRNAs in stem cells and differentiating daughter cells. Such a role has been shown in embryonic stem cells, germline stem cells and various somatic tissue stem cells. These findings reveal a new dimension of gene regulation in controlling stem cell fate and behaviour.

[Progress in epidermal stem cells].

PubMed

Wang, Li-Juan; Wang, You-Liang; Yang, Xiao

2010-03-01

Mammalian skin epidermis contains different epidermal stem cell pools which contribute to the homeostasis and repair of skin epithelium. Epidermal stem cells possess two essential features common to all stem cells: self-renewal and differentiation. Disturbing the balance between self-renewal and differentiation of epidermal stem cell often causes tumors or other skin diseases. Epidermal stem cell niches provide a special microenvironment that maintains a balance of stem cell quiescence and activity. This review primarily concentrates on the following points of the epidermal stem cells: the existing evidences, the self-renewal and differentiation, the division pattern, the signal pathways regulating self-renewal and differentiation, and the microenvironment (niche) and macroenvironment maintaining the homeostasis of stem cells.

[Research progress of intervertebral disc endogenous stem cells for intervertebral disc regeneration].

PubMed

Liang, Hang; Deng, Xiangyu; Shao, Zengwu

2017-10-01

To summarize the research progress of intervertebral disc endogenous stem cells for intervertebral disc regeneration and deduce the therapeutic potential of endogenous repair for intervertebral disc degeneration. The original articles about intervertebral disc endogenous stem cells for intervertebral disc regeneration were extensively reviewed; the reparative potential in vivo and the extraction and identification in vitro of intervertebral disc endogenous stem cells were analyzed; the prospect of endogenous stem cells for intervertebral disc regeneration was predicted. Stem cell niche present in the intervertebral discs, from which stem cells migrate to injured tissues and contribute to tissues regeneration under certain specific microenvironment. Moreover, the migration of stem cells is regulated by chemokines system. Tissue specific progenitor cells have been identified and successfully extracted and isolated. The findings provide the basis for biological therapy of intervertebral disc endogenous stem cells. Intervertebral disc endogenous stem cells play a crucial role in intervertebral disc regeneration. Therapeutic strategy of intervertebral disc endogenous stem cells is proven to be a promising biological approach for intervertebral disc regeneration.

Amnion-derived stem cells: in quest of clinical applications

PubMed Central

2011-01-01

In the promising field of regenerative medicine, human perinatal stem cells are of great interest as potential stem cells with clinical applications. Perinatal stem cells could be isolated from normally discarded human placentae, which are an ideal cell source in terms of availability, the fewer number of ethical concerns, less DNA damage, and so on. Numerous studies have demonstrated that some of the placenta-derived cells possess stem cell characteristics like pluripotent differentiation ability, particularly in amniotic epithelial (AE) cells. Term human amniotic epithelium contains a relatively large number of stem cell marker-positive cells as an adult stem cell source. In this review, we introduce a model theory of why so many AE cells possess stem cell characteristics. We also describe previous work concerning the therapeutic applications and discuss the pluripotency of the AE cells and potential pitfalls for amnion-derived stem cell research. PMID:21596003

The role of stem cells in aesthetic surgery: fact or fiction?

PubMed

McArdle, Adrian; Senarath-Yapa, Kshemendra; Walmsley, Graham G; Hu, Michael; Atashroo, David A; Tevlin, Ruth; Zielins, Elizabeth; Gurtner, Geoffrey C; Wan, Derrick C; Longaker, Michael T

2014-08-01

Stem cells are attractive candidates for the development of novel therapies, targeting indications that involve functional restoration of defective tissue. Although most stem cell therapies are new and highly experimental, there are clinics around the world that exploit vulnerable patients with the hope of offering supposed stem cell therapies, many of which operate without credible scientific merit, oversight, or other patient protection. The authors review the potential and the drawbacks of incorporation of stem cells in cosmetic procedures. A review of U.S. Food and Drug Administration-approved indications and ongoing clinical trials with adipose stem cells is provided. Furthermore, a "snapshot" analysis of Web sites using the search terms "stem cell therapy" or "stem cell treatment" or "stem cell facelift" was performed. Despite the protective net cast by regulatory agencies such as the U.S. Food and Drug Administration and professional societies such as the American Society of Plastic Surgeons, the authors are witnessing worrying advertisements for procedures such as stem cell face lifts, stem cell breast augmentations, and even stem cell vaginal rejuvenation. The marketing and promotion of stem cell procedures in aesthetic surgery is not adequately supported by clinical evidence in the majority of cases. Stem cells offer tremendous potential, but the marketplace is saturated with unsubstantiated and sometimes fraudulent claims that may place patients at risk. With plastic surgeons at the forefront of stem cell-based regenerative medicine, it is critically important that they provide an example of a rigorous approach to research, data collection, and advertising of stem cell therapies.

Polymer microarray technology for stem cell engineering

PubMed Central

Coyle, Robert; Jia, Jia; Mei, Ying

2015-01-01

Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. During the past decade, significant progress has been made in developing soluble factors (e.g., small molecules and growth factors) to direct stem cells into a desired phenotype. However, the current lack of suitable synthetic materials to regulate stem cell activity has limited the realization of the enormous potential of stem cells. This can be attributed to a large number of materials properties (e.g., chemical structures and physical properties of materials) that can affect stem cell fate. This makes it challenging to design biomaterials to direct stem cell behavior. To address this, polymer microarray technology has been developed to rapidly identify materials for a variety of stem cell applications. In this article, we summarize recent developments in polymer array technology and their applications in stem cell engineering. Statement of significance Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. In the last decade, significant progress has been made in developing chemically defined media to direct stem cells into a desired phenotype. However, the current lack of the suitable synthetic materials to regulate stem cell activities has been limiting the realization of the potential of stem cells. This can be attributed to the number of variables in material properties (e.g., chemical structures and physical properties) that can affect stem cells. Polymer microarray technology has shown to be a powerful tool to rapidly identify materials for a variety of stem cell applications. Here we summarize recent developments in polymer array technology and their applications in stem cell engineering. PMID:26497624

Stem cells in kidney regeneration.

PubMed

Yokote, Shinya; Yokoo, Takashi

2012-01-01

Currently many efforts are being made to apply regenerative medicine to kidney diseases using several types of stem/progenitor cells, such as mesenchymal stem cells, renal stem/progenitor cells, embryonic stem cells and induced pluripotent stem cells. Stem cells have the ability to repair injured organs and ameliorate damaged function. The strategy for kidney tissue repair is the recruitment of stem cells and soluble reparative factors to the kidney to elicit tissue repair and the induction of dedifferentiation of resident renal cells. On the other hand, where renal structure is totally disrupted, absolute kidney organ regeneration is needed to rebuild a whole functional kidney. In this review, we describe current advances in stem cell research for kidney tissue repair and de novo organ regeneration.

Stem Cell Sciences plc.

PubMed

Daniels, Sebnem

2006-09-01

Stem Cell Sciences' core objective is to develop safe and effective stem cell-based therapies for currently incurable diseases. In order to achieve this goal, Stem Cell Sciences recognizes the need for multiple technologies and a globally integrated stem cell initiative. The key challenges for the successful application of stem cells in the clinic is the need for a reproducible supply of pure, fully characterized stem cells that have been grown in suitable conditions for use in the clinic.

Fusion with stem cell makes the hepatocellular carcinoma cells similar to liver tumor-initiating cells.

PubMed

Wang, Ran; Chen, Shuxun; Li, Changxian; Ng, Kevin Tak Pan; Kong, Chi-wing; Cheng, Jinping; Cheng, Shuk Han; Li, Ronald A; Lo, Chung Mau; Man, Kwan; Sun, Dong

2016-02-04

Cell fusion is a fast and highly efficient technique for cells to acquire new properties. The fusion of somatic cells with stem cells can reprogram somatic cells to a pluripotent state. Our research on the fusion of stem cells and cancer cells demonstrates that the fused cells can exhibit stemness and cancer cell-like characteristics. Thus, tumor-initiating cell-like cells are generated. We employed laser-induced single-cell fusion technique to fuse the hepatocellular carcinoma cells and human embryonic stem cells (hESC). Real-time RT-PCR, flow cytometry and in vivo tumorigenicity assay were adopted to identify the gene expression difference. We successfully produced a fused cell line that coalesces the gene expression information of hepatocellular carcinoma cells and stem cells. Experimental results showed that the fused cells expressed cancer and stemness markers as well as exhibited increased resistance to drug treatment and enhanced tumorigenesis. Fusion with stem cells transforms liver cancer cells into tumor initiating-like cells. Results indicate that fusion between cancer cell and stem cell may generate tumor initiating-like cells.

The characterization of small hypoattenuating renal masses on contrast-enhanced CT☆

PubMed Central

Patel, Neesha S.; Poder, Liina; Wang, Zhen J.; Yeh, Benjamin M.; Qayyum, Aliya; Jin, Hua; Coakley, Fergus V.

2011-01-01

Purpose To determine if small hypoattenuating renal masses can be characterized as simple cysts or renal cell carcinomas on contrast-enhanced computed tomography (CT). Materials and methods We retrospectively identified 20 small (≤1.5 cm) hypoattenuating renal masses seen on contrast enhanced CT, consisting of 14 simple cysts and six renal cell carcinomas. Three independent readers recorded subjective visual impression (five-point scale from 1=definitely fluid to 5=definitely solid), CT attenuation, border (well circumscribed or ill defined), and shape (ovoid or irregular) for each lesion. Results The overall area under the receiver operator characteristic curves for subjective visual impression, CT attenuation, border, and shape were 0.97, 0.82, 0.59, and 0.55, respectively. Using dichotomized ratings (1–2=cyst and 3–5=carcinoma), subjective impression had a sensitivity and specificity of 100% and 79–100%, respectively, for the diagnosis of renal cell carcinoma. Using a threshold of 50 Hounsfield Units (HU) or more, CT attenuation had a sensitivity and specificity of 100% and 43–64%, respectively. Conclusion Small hypoattenuating renal masses can be characterized with reasonable accuracy by subjective impression and CT attenuation; lesions that appear solid on visual inspection or have an attenuation value of 50 HU or more are likely to be renal cell carcinoma. © 2009 Elsevier Inc. All rights reserved. PMID:19559352

Stem cell-derived vascular endothelial cells and their potential application in regenerative medicine

USDA-ARS?s Scientific Manuscript database

Although a 'vascular stem cell' population has not been identified or generated, vascular endothelial and mural cells (smooth muscle cells and pericytes) can be derived from currently known pluripotent stem cell sources, including human embryonic stem cells and induced pluripotent stem cells. We rev...

Hematopoietic cell differentiation from embryonic and induced pluripotent stem cells

PubMed Central

2013-01-01

Pluripotent stem cells, both embryonic stem cells and induced pluripotent stem cells, are undifferentiated cells that can self-renew and potentially differentiate into all hematopoietic lineages, such as hematopoietic stem cells (HSCs), hematopoietic progenitor cells and mature hematopoietic cells in the presence of a suitable culture system. Establishment of pluripotent stem cells provides a comprehensive model to study early hematopoietic development and has emerged as a powerful research tool to explore regenerative medicine. Nowadays, HSC transplantation and hematopoietic cell transfusion have successfully cured some patients, especially in malignant hematological diseases. Owing to a shortage of donors and a limited number of the cells, hematopoietic cell induction from pluripotent stem cells has been regarded as an alternative source of HSCs and mature hematopoietic cells for intended therapeutic purposes. Pluripotent stem cells are therefore extensively utilized to facilitate better understanding in hematopoietic development by recapitulating embryonic development in vivo, in which efficient strategies can be easily designed and deployed for the generation of hematopoietic lineages in vitro. We hereby review the current progress of hematopoietic cell induction from embryonic stem/induced pluripotent stem cells. PMID:23796405

Stem Cell Basics

MedlinePlus

... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... Basics » Stem Cell Basics I. Back to top Stem Cell Basics I. Introduction: What are stem cells, and ...

TOPICAL REVIEW: Stem cells engineering for cell-based therapy

NASA Astrophysics Data System (ADS)

Taupin, Philippe

2007-09-01

Stem cells carry the promise to cure a broad range of diseases and injuries, from diabetes, heart and muscular diseases, to neurological diseases, disorders and injuries. Significant progresses have been made in stem cell research over the past decade; the derivation of embryonic stem cells (ESCs) from human tissues, the development of cloning technology by somatic cell nuclear transfer (SCNT) and the confirmation that neurogenesis occurs in the adult mammalian brain and that neural stem cells (NSCs) reside in the adult central nervous system (CNS), including that of humans. Despite these advances, there may be decades before stem cell research will translate into therapy. Stem cell research is also subject to ethical and political debates, controversies and legislation, which slow its progress. Cell engineering has proven successful in bringing genetic research to therapy. In this review, I will review, in two examples, how investigators are applying cell engineering to stem cell biology to circumvent stem cells' ethical and political constraints and bolster stem cell research and therapy.

From Banking to International Governance: Fostering Innovation in Stem Cell Research

PubMed Central

Isasi, Rosario; Knoppers, Bartha M.

2011-01-01

Stem cell banks are increasingly recognized as an essential resource of biological materials for both basic and translational stem cell research. By providing transnational access to quality controlled and ethically sourced stem cell lines, stem cell banks seek to foster international collaboration and innovation. However, given that national stem cell banks operate under different policy, regulatory and commercial frameworks, the transnational sharing of stem cell materials and data can be complicating. This paper will provide an overview of the most pressing challenges regarding the governance of stem cell banks, and the difficulties in designing regulatory and commercial frameworks that foster stem cell research. Moreover, the paper will shed light on the numerous international initiatives that have arisen to help harmonize and standardize stem cell banking and research processes to overcome such challenges. PMID:21904557

Stem Cells Transplantation in the Treatment of Patients with Liver Failure.

PubMed

Tao, Ya-Chao; Wang, Meng-Lan; Chen, En-Qiang; Tang, Hong

2018-02-23

Liver failure is a life-threatening liver disease encompassing severe acute deterioration of liver function. Emergency liver transplantation is the only curative treatment for liver failure, but is restricted by the severe shortage of organ donors. Stem cell, including embroyonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, hematopoietic stem cells and hepatic progenitor cells, have capacity to proliferate and differentiate and could be used in a variety of liver diseases including hereditary liver diseases, cirrhosis and liver failure. We summarized the basic experimental and clinical advances of stem cell transplantation in liver failure treatment, and also discussed the advantages and disadvantage of different stem cells subtype in this field, aiming to provide a perspective on the stem cell-based therapy for liver failure. Stem cells, especially mesenchymal stem cells (mainly low immunogenicity and paracrine characteristics) and induced pluripotent stem cells (generation of desired cell type from somatic cell), are feasible candidates for cell therapy in the treatment of liver failure, but there are some drawbacks remaining to be resolved, such as low engraftment, cryotpreservation methods and tumorigenesis. Stem cell transplantation is a promising but challenging strategy and paves a new way for curing liver failure. But more efforts need to be made to overcome problems before this new strategy could be safely and effectively applied to humans. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Recent Progress in Stem Cell Modification for Cardiac Regeneration

PubMed Central

Voronina, Natalia; Steinhoff, Gustav

2018-01-01

During the past decades, stem cell-based therapy has acquired a promising role in regenerative medicine. The application of novel cell therapeutics for the treatment of cardiovascular diseases could potentially achieve the ambitious aim of effective cardiac regeneration. Despite the highly positive results from preclinical studies, data from phase I/II clinical trials are inconsistent and the improvement of cardiac remodeling and heart performance was found to be quite limited. The major issues which cardiac stem cell therapy is facing include inefficient cell delivery to the site of injury, accompanied by low cell retention and weak effectiveness of remaining stem cells in tissue regeneration. According to preclinical and clinical studies, various stem cells (adult stem cells, embryonic stem cells, and induced pluripotent stem cells) represent the most promising cell types so far. Beside the selection of the appropriate cell type, researchers have developed several strategies to produce “second-generation” stem cell products with improved regenerative capacity. Genetic and nongenetic modifications, chemical and physical preconditioning, and the application of biomaterials were found to significantly enhance the regenerative capacity of transplanted stem cells. In this review, we will give an overview of the recent developments in stem cell engineering with the goal to facilitate stem cell delivery and to promote their cardiac regenerative activity. PMID:29535769

Eat, breathe, ROS: controlling stem cell fate through metabolism.

PubMed

Kubli, Dieter A; Sussman, Mark A

2017-05-01

Research reveals cardiac regeneration exists at levels previously deemed unattainable. Clinical trials using stem cells demonstrate promising cardiomyogenic and regenerative potential but insufficient contractile recovery. Incomplete understanding of the biology of administered cells likely contributes to inconsistent patient outcomes. Metabolism is a core component of many well-characterized stem cell types, and metabolic changes fundamentally alter stem cell fate from self-renewal to lineage commitment, and vice versa. However, the metabolism of stem cells currently studied for cardiac regeneration remains incompletely understood. Areas covered: Key metabolic features of stem cells are reviewed and unique stem cell metabolic characteristics are discussed. Metabolic changes altering stem cell fate are considered from quiescence and self-renewal to lineage commitment. Key metabolic concepts are applied toward examining cardiac regeneration through stem cell-based approaches, and clinical implications of current cell therapies are evaluated to identify potential areas of improvement. Expert commentary: The metabolism and biology of stem cells used for cardiac therapy remain poorly characterized. A growing appreciation for the fundamental relationship between stem cell functionality and metabolic phenotype is developing. Future studies unraveling links between cardiac stem cell metabolism and regenerative potential may considerably improve treatment strategies and therapeutic outcomes.

Eat, breathe, ROS: controlling stem cell fate through metabolism

PubMed Central

Kubli, Dieter A.; Sussman, Mark A.

2017-01-01

Introduction Research reveals cardiac regeneration exists at levels previously deemed unattainable. Clinical trials using stem cells demonstrate promising cardiomyogenic and regenerative potential but insufficient contractile recovery. Incomplete understanding of the biology of administered cells likely contributes to inconsistent patient outcomes. Metabolism is a core component of many well-characterized stem cell types, and metabolic changes fundamentally alter stem cell fate from self-renewal to lineage commitment, and vice versa. However, the metabolism of stem cells currently studied for cardiac regeneration remains incompletely understood. Areas covered Key metabolic features of stem cells are reviewed and unique stem cell metabolic characteristics are discussed. Metabolic changes altering stem cell fate are considered from quiescence and self-renewal to lineage commitment. Key metabolic concepts are applied toward examining cardiac regeneration through stem cell-based approaches, and clinical implications of current cell therapies are evaluated to identify potential areas of improvement. Expert commentary The metabolism and biology of stem cells used for cardiac therapy remain poorly characterized. A growing appreciation for the fundamental relationship between stem cell functionality and metabolic phenotype is developing. Future studies unraveling links between cardiac stem cell metabolism and regenerative potential may considerably improve treatment strategies and therapeutic outcomes. PMID:28406333

Therapeutic strategies involving uterine stem cells in reproductive medicine.

PubMed

Simoni, Michael; Taylor, Hugh S

2018-06-01

The current review provides an update on recent advances in stem cell biology relevant to female reproduction. Stem cells are undifferentiated cells that often serve as a reservoir of cells to regenerate tissue in settings or injury or cell loss. The endometrium has progenitor stem cells that can replace all of the endometrium during each menstrual cycle. In addition, multipotent endometrial cells replace these progenitor cells when depleted. Recruitment of stem cells from outside of the uterus occurs in setting of increased demand such as ischemia or injury. Bone marrow-derived multipotent stem cells are recruited to the uterus by estrogen or injury-induced expression of the chemokine CXCL12. In the setting of overwhelming injury, especially in the setting of low estrogen levels, there may be insufficient stem cell recruitment to adequately repair the uterus resulting in conditions such as Asherman syndrome or other endometrial defects. In contrast, excessive recruitment of stem cells underlies endometriosis. Enhanced understanding of stem-cell mobilization, recruitment, and engraftment has created the possibility of improved therapy for endometrial defects and endometriosis through enhanced manipulation of stem-cell trafficking. Further, the normal endometrium is a rich source of multipotent stem cells that can be used for numerous applications in regenerative medicine beyond reproduction. A better understanding of reproductive stem-cell biology may allow improved treatment of endometrial disease such as Asherman syndrome and other endometrial receptivity defects. Inhibiting stem-cell mobilization may also be helpful in endometriosis therapy. Finally, endometrial derived multipotent stem cells may play a crucial role in cell therapy for regenerative medicine.

Gene screening of Wharton's jelly derived stem cells.

PubMed

Mechiche Alami, S; Velard, F; Draux, F; Siu Paredes, F; Josse, J; Lemaire, F; Gangloff, S C; Graesslin, O; Laurent-Maquin, D; Kerdjoudj, H

2014-01-01

Stem cells are the most powerful candidate for the treatment of various diseases. Suitable stem cell source should be harvested with minimal invasive procedure, found in great quantity, and transplanted with no risk of immune response and tumor formation. Fetal derived stem cells have been introduced as an excellent alternative to adult and embryonic stem cells use, but unfortunately, their degree of "stemness" and molecular characterization is still unclear. Several studies have been performed deciphering whether fetal stem cells meet the needs of regenerative medicine. We believe that a transcriptomic screening of Wharton's jelly stem cells will bring insights on cell population features.

Stem Cell Banking for Regenerative and Personalized Medicine

PubMed Central

Harris, David T.

2014-01-01

Regenerative medicine, tissue engineering and gene therapy offer the opportunity to treat and cure many of today’s intractable afflictions. These approaches to personalized medicine often utilize stem cells to accomplish these goals. However, stem cells can be negatively affected by donor variables such as age and health status at the time of collection, compromising their efficacy. Stem cell banking offers the opportunity to cryogenically preserve stem cells at their most potent state for later use in these applications. Practical stem cell sources include bone marrow, umbilical cord blood and tissue, and adipose tissue. Each of these sources contains stem cells that can be obtained from most individuals, without too much difficulty and in an economical fashion. This review will discuss the advantages and disadvantages of each stem cell source, factors to be considered when contemplating banking each stem cell source, the methodology required to bank each stem cell source, and finally, current and future clinical uses of each stem cell source. PMID:28548060

Chir99021 and Valproic acid reduce the proliferative advantage of Apc mutant cells.

PubMed

Langlands, Alistair J; Carroll, Thomas D; Chen, Yu; Näthke, Inke

2018-02-15

More than 90% of colorectal cancers carry mutations in Apc that drive tumourigenesis. A 'just-right' signalling model proposes that Apc mutations stimulate optimal, but not excessive Wnt signalling, resulting in a growth advantage of Apc mutant over wild-type cells. Reversal of this growth advantage constitutes a potential therapeutic approach. We utilised intestinal organoids to compare the growth of Apc mutant and wild-type cells. Organoids derived from Apc Min/+ mice recapitulate stages of intestinal polyposis in culture. They eventually form spherical cysts that reflect the competitive growth advantage of cells that have undergone loss of heterozygosity (LOH). We discovered that this emergence of cysts was inhibited by Chiron99021 and Valproic acid, which potentiates Wnt signalling. Chiron99021 and Valproic acid restrict the growth advantage of Apc mutant cells while stimulating that of wild-type cells, suggesting that excessive Wnt signalling reduces the relative fitness of Apc mutant cells. As a proof of concept, we demonstrated that Chiron99021-treated Apc mutant organoids were rendered susceptible to TSA-induced apoptosis, while wild-type cells were protected.

Nine Things to Know About Stem Cell Treatments

MedlinePlus

... Toggle Nav Nine Things To Know About Stem Cell Treatments Home > Stem Cells and Medicine > Nine Things ... About Stem Cell Treatments Many clinics offering stem cell treatments make claims that are not supported by ...

Cancer (stem) cell differentiation: An inherent or acquired property?

PubMed

Mohr, Marieke; Zänker, Kurt S; Dittmar, Thomas

2015-12-01

There is a growing list of data indicating that cancer (stem) cells could functionally adapt foreign tissue features, such as endothelial-like cells or neuroendocrine cells, express lineage markers or could differentiate into various lineages in response to appropriate differentiation criteria. The finding that cancer (stem) cells may possess some kind of differentiation capacity poses the question whether this might be an inherent or acquired property. Cancer stem cells share stem cell characteristics and may thus possess an inherent differentiation capacity enabling the cells to respond to various differentiation stimuli. Considering the plasticity of cancer (stem) cells, even non-tumorigenic (and putatively non-differentiable) tumor cells could give rise to tumorigenic tumor stem cells, exhibiting stem cell characteristics including an inherent differentiation capacity. On the contrary, cancer (stem) cells may have acquired differentiation capacity as a consequence of a previous cell fusion event with cell types exhibiting differentiation potential and being fusogenic, such as macrophages or stem cells. Of pivotal interest in a tumor context are macrophages, which chiefly foster the chronically inflamed tumor microenvironment. Because chronically inflamed tissue is a well-known trigger for cell fusion and both macrophages and stem cells are highly fusogenic we conclude that cell fusion events between these cell types and cancer (stem) cells should frequently occur, thereby giving rise to hybrid cells exhibiting not only novel properties, like an enhanced metastatogenic phenotype, but also parental characteristics, such as differentiation capacity. Conceivably, the combination of both properties might be advantageous for metastasizing cancer (stem) cells to adapt better and faster to a foreign organ tissue environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sox10+ adult stem cells contribute to biomaterial encapsulation and microvascularization

PubMed Central

Wang, Dong; Wang, Aijun; Wu, Fan; Qiu, Xuefeng; Li, Ye; Chu, Julia; Huang, Wen-Chin; Xu, Kang; Gong, Xiaohua; Li, Song

2017-01-01

Implanted biomaterials and biomedical devices generally induce foreign body reaction and end up with encapsulation by a dense avascular fibrous layer enriched in extracellular matrix. Fibroblasts/myofibroblasts are thought to be the major cell type involved in encapsulation, but it is unclear whether and how stem cells contribute to this process. Here we show, for the first time, that Sox10+ adult stem cells contribute to both encapsulation and microvessel formation. Sox10+ adult stem cells were found sparsely in the stroma of subcutaneous loose connective tissues. Upon subcutaneous biomaterial implantation, Sox10+ stem cells were activated and recruited to the biomaterial scaffold, and differentiated into fibroblasts and then myofibroblasts. This differentiation process from Sox10+ stem cells to myofibroblasts could be recapitulated in vitro. On the other hand, Sox10+ stem cells could differentiate into perivascular cells to stabilize newly formed microvessels. Sox10+ stem cells and endothelial cells in three-dimensional co-culture self-assembled into microvessels, and platelet-derived growth factor had chemotactic effect on Sox10+ stem cells. Transplanted Sox10+ stem cells differentiated into smooth muscle cells to stabilize functional microvessels. These findings demonstrate the critical role of adult stem cells in tissue remodeling and unravel the complexity of stem cell fate determination. PMID:28071739

Tumor suppressors Sav/Scrib and oncogene Ras regulate stem cell transformation in adult Drosophila Malpighian Tubules

PubMed Central

Zeng, Xiankun; Singh, Shree Ram; Hou, David; Hou, Steven X.

2012-01-01

An increasing body of evidence suggests that tumors might originate from a few transformed cells that share many properties with normal stem cells. However, it remains unclear how normal stem cells are transformed into cancer stem cells. Here, we demonstrated that mutations causing the loss of tumor suppressor Sav or Scrib or activation of the oncogene Ras transform normal stem cells into cancer stem cells through a multistep process in the adult Drosophila Malpighian Tubules (MTs). In wild-type MTs, each stem cell generates one self-renewing and one differentiating daughter cell. However, in flies with loss-of-function sav or scrib or gain-of-function Ras mutations, both daughter cells grew and behaved like stem cells, leading to the formation of tumors in MTs. Ras functioned downstream of Sav and Scrib in regulating the stem cell transformation. The Ras-transformed stem cells exhibited many of the hallmarks of cancer, such as increased proliferation, reduced cell death, and failure to differentiate. We further demonstrated that several signal transduction pathways (including MEK/MAPK, RhoA, PKA, and TOR) mediate Rasṕ function in the stem cell transformation. Therefore, we have identified a molecular mechanism that regulates stem cell transformation, and this finding may lead to strategies for preventing tumor formation in certain organs. PMID:20432470

The king is dead, long live the king: entering a new era of stem cell research and clinical development.

PubMed

Ichim, Thomas; Riordan, Neil H; Stroncek, David F

2011-12-20

In mid November the biopharma industry was shocked by the announcement from Geron that they were ending work on embryonic stem cell research and therapy. For more than 10 years the public image of all stem cell research has been equated with embryonic stem cells. Unfortunately, a fundamentally important medical and financial fact was being ignored: embryonic stem cell therapy is extremely immature. In parallel to efforts in embryonic stem cell research and development, scientists and physicians in the field of adult stem cells realized that the natural role of adult stem cells in the body is to promote healing and to act like endogenous "repair cells" and, as a result, numerous companies have entered the field of adult stem cell therapy with the goal of expanding numbers of adult stem cells for administration to patients with various conditions. In contrast to embryonic stem cells, which are extremely expensive and potentially dangerous, adult cell cells are inexpensive and have an excellent safety record when used in humans. Many studies are now showing that adult stem cells are practical, patient-applicable, therapeutics that are very close to being available for incorporation into the practice of medicine. These events signal the entrance of the field of stem cells into a new era: an era where hype and misinformation no longer triumph over economic and medical realities.

Control of stem cell fate by engineering their micro and nanoenvironment

PubMed Central

Griffin, Michelle F; Butler, Peter E; Seifalian, Alexander M; Kalaskar, Deepak M

2015-01-01

Stem cells are capable of long-term self-renewal and differentiation into specialised cell types, making them an ideal candidate for a cell source for regenerative medicine. The control of stem cell fate has become a major area of interest in the field of regenerative medicine and therapeutic intervention. Conventional methods of chemically inducing stem cells into specific lineages is being challenged by the advances in biomaterial technology, with evidence highlighting that material properties are capable of driving stem cell fate. Materials are being designed to mimic the clues stem cells receive in their in vivo stem cell niche including topographical and chemical instructions. Nanotopographical clues that mimic the extracellular matrix (ECM) in vivo have shown to regulate stem cell differentiation. The delivery of ECM components on biomaterials in the form of short peptides sequences has also proved successful in directing stem cell lineage. Growth factors responsible for controlling stem cell fate in vivo have also been delivered via biomaterials to provide clues to determine stem cell differentiation. An alternative approach to guide stem cells fate is to provide genetic clues including delivering DNA plasmids and small interfering RNAs via scaffolds. This review, aims to provide an overview of the topographical, chemical and molecular clues that biomaterials can provide to guide stem cell fate. The promising features and challenges of such approaches will be highlighted, to provide directions for future advancements in this exciting area of stem cell translation for regenerative medicine. PMID:25621104

The Neurovascular Properties of Dental Stem Cells and Their Importance in Dental Tissue Engineering

PubMed Central

Ratajczak, Jessica; Bronckaers, Annelies; Dillen, Yörg; Gervois, Pascal; Vangansewinkel, Tim; Driesen, Ronald B.; Wolfs, Esther; Lambrichts, Ivo

2016-01-01

Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs) have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair. PMID:27688777

Multipotent Stem Cell and Reproduction.

PubMed

Khanlarkhani, Neda; Baazm, Maryam; Mohammadzadeh, Farzaneh; Najafi, Atefeh; Mehdinejadiani, Shayesteh; Sobhani, Aligholi

Stem cells are self-renewing and undifferentiated cell types that can be differentiate into functional cells. Stem cells can be classified into two main types based on their source of origin: Embryonic and Adult stem cells. Stem cells also classified based on the range of differentiation potentials into Totipotent, Pluripotent, Multipotent, and Unipotent. Multipotent stem cells have the ability to differentiate into all cell types within one particular lineage. There are plentiful advantages and usages for multipotent stem cells. Multipotent Stem cells act as a significant key in procedure of development, tissue repair, and protection. The accessibility and adaptability of these amazing cells create them a great therapeutic choice for different part of medical approaches, and it becomes interesting topic in the scientific researches to found obvious method for the most advantageous use of MSC-based therapies. Recent studies in the field of stem cell biology have provided new perspectives and opportunities for the treatment of infertility disorders.

Strategies to improve homing of mesenchymal stem cells for greater efficacy in stem cell therapy.

PubMed

Naderi-Meshkin, Hojjat; Bahrami, Ahmad Reza; Bidkhori, Hamid Reza; Mirahmadi, Mahdi; Ahmadiankia, Naghmeh

2015-01-01

Stem/progenitor cell-based therapeutic approach in clinical practice has been an elusive dream in medical sciences, and improvement of stem cell homing is one of major challenges in cell therapy programs. Stem/progenitor cells have a homing response to injured tissues/organs, mediated by interactions of chemokine receptors expressed on the cells and chemokines secreted by the injured tissue. For improvement of directed homing of the cells, many techniques have been developed either to engineer stem/progenitor cells with higher amount of chemokine receptors (stem cell-based strategies) or to modulate the target tissues to release higher level of the corresponding chemokines (target tissue-based strategies). This review discusses both of these strategies involved in the improvement of stem cell homing focusing on mesenchymal stem cells as most frequent studied model in cellular therapies. © 2014 International Federation for Cell Biology.

College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning

ERIC Educational Resources Information Center

Concannon, James P.; Siegel, Marcelle A.; Halverson, Kristy; Freyermuth, Sharyn

2010-01-01

In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before…

Stem cell biobanks.

PubMed

Bardelli, Silvana

2010-04-01

Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment.

Muscle Stem Cells: A Model System for Adult Stem Cell Biology.

PubMed

Cornelison, Ddw; Perdiguero, Eusebio

2017-01-01

Skeletal muscle stem cells, originally termed satellite cells for their position adjacent to differentiated muscle fibers, are absolutely required for the process of skeletal muscle repair and regeneration. In the last decade, satellite cells have become one of the most studied adult stem cell systems and have emerged as a standard model not only in the field of stem cell-driven tissue regeneration but also in stem cell dysfunction and aging. Here, we provide background in the field and discuss recent advances in our understanding of muscle stem cell function and dysfunction, particularly in the case of aging, and the potential involvement of muscle stem cells in genetic diseases such as the muscular dystrophies.

Redox regulation of plant stem cell fate.

PubMed

Zeng, Jian; Dong, Zhicheng; Wu, Haijun; Tian, Zhaoxia; Zhao, Zhong

2017-10-02

Despite the importance of stem cells in plant and animal development, the common mechanisms of stem cell maintenance in both systems have remained elusive. Recently, the importance of hydrogen peroxide (H 2 O 2 ) signaling in priming stem cell differentiation has been extensively studied in animals. Here, we show that different forms of reactive oxygen species (ROS) have antagonistic roles in plant stem cell regulation, which were established by distinct spatiotemporal patterns of ROS-metabolizing enzymes. The superoxide anion (O2·-) is markedly enriched in stem cells to activate WUSCHEL and maintain stemness, whereas H 2 O 2 is more abundant in the differentiating peripheral zone to promote stem cell differentiation. Moreover, H 2 O 2 negatively regulates O2·- biosynthesis in stem cells, and increasing H 2 O 2 levels or scavenging O2·- leads to the termination of stem cells. Our results provide a mechanistic framework for ROS-mediated control of plant stem cell fate and demonstrate that the balance between O2·- and H 2 O 2 is key to stem cell maintenance and differentiation. © 2017 The Authors.

Ocular Stem Cell Research from Basic Science to Clinical Application: A Report from Zhongshan Ophthalmic Center Ocular Stem Cell Symposium

PubMed Central

Ouyang, Hong; Goldberg, Jeffrey L.; Chen, Shuyi; Li, Wei; Xu, Guo-Tong; Li, Wei; Zhang, Kang; Nussenblatt, Robert B.; Liu, Yizhi; Xie, Ting; Chan, Chi-Chao; Zack, Donald J.

2016-01-01

Stem cells hold promise for treating a wide variety of diseases, including degenerative disorders of the eye. The eye is an ideal organ for stem cell therapy because of its relative immunological privilege, surgical accessibility, and its being a self-contained system. The eye also has many potential target diseases amenable to stem cell-based treatment, such as corneal limbal stem cell deficiency, glaucoma, age-related macular degeneration (AMD), and retinitis pigmentosa (RP). Among them, AMD and glaucoma are the two most common diseases, affecting over 200 million people worldwide. Recent results on the clinical trial of retinal pigment epithelial (RPE) cells from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) in treating dry AMD and Stargardt’s disease in the US, Japan, England, and China have generated great excitement and hope. This marks the beginning of the ocular stem cell therapy era. The recent Zhongshan Ophthalmic Center Ocular Stem Cell Symposium discussed the potential applications of various stem cell types in stem cell-based therapies, drug discoveries and tissue engineering for treating ocular diseases. PMID:27102165

StemTextSearch: Stem cell gene database with evidence from abstracts.

PubMed

Chen, Chou-Cheng; Ho, Chung-Liang

2017-05-01

Previous studies have used many methods to find biomarkers in stem cells, including text mining, experimental data and image storage. However, no text-mining methods have yet been developed which can identify whether a gene plays a positive or negative role in stem cells. StemTextSearch identifies the role of a gene in stem cells by using a text-mining method to find combinations of gene regulation, stem-cell regulation and cell processes in the same sentences of biomedical abstracts. The dataset includes 5797 genes, with 1534 genes having positive roles in stem cells, 1335 genes having negative roles, 1654 genes with both positive and negative roles, and 1274 with an uncertain role. The precision of gene role in StemTextSearch is 0.66, and the recall is 0.78. StemTextSearch is a web-based engine with queries that specify (i) gene, (ii) category of stem cell, (iii) gene role, (iv) gene regulation, (v) cell process, (vi) stem-cell regulation, and (vii) species. StemTextSearch is available through http://bio.yungyun.com.tw/StemTextSearch.aspx. Copyright © 2017. Published by Elsevier Inc.

Application of Stem Cell Technology in Dental Regenerative Medicine.

PubMed

Feng, Ruoxue; Lengner, Chistopher

2013-07-01

In this review, we summarize the current literature regarding the isolation and characterization of dental tissue-derived stem cells and address the potential of these cell types for use in regenerative cell transplantation therapy. Looking forward, platforms for the delivery of stem cells via scaffolds and the use of growth factors and cytokines for enhancing dental stem cell self-renewal and differentiation are discussed. We aim to understand the developmental origins of dental tissues in an effort to elucidate the molecular pathways governing the genesis of somatic dental stem cells. The advantages and disadvantages of several dental stem cells are discussed, including the developmental stage and specific locations from which these cells can be purified. In particular, stem cells from human exfoliated deciduous teeth may act as a very practical and easily accessibly reservoir for autologous stem cells and hold the most value in stem cell therapy. Dental pulp stem cells and periodontal ligament stem cells should also be considered for their triple lineage differentiation ability and relative ease of isolation. Further, we address the potentials and limitations of induced pluripotent stem cells as a cell source in dental regenerative. From an economical and a practical standpoint, dental stem cell therapy would be most easily applied in the prevention of periodontal ligament detachment and bone atrophy, as well as in the regeneration of dentin-pulp complex. In contrast, cell-based tooth replacement due to decay or other oral pathology seems, at the current time, an untenable approach.

Genetics Home Reference: megalencephalic leukoencephalopathy with subcortical cysts

MedlinePlus

... is unable to correctly transport GlialCAM and MLC1 proteins to cell junctions. It is unknown how a lack of functional MLC1 or GlialCAM protein at cell junctions in the brain impairs brain development and ...

The UK Stem Cell Bank: a UK government-funded, international resource center for stem cell research.

PubMed

Stacey, Glyn; Hunt, Charles J

2006-01-01

The UK Stem Cell Bank is a UK Research Council-funded initiative that aims to provide ethically sourced and quality controlled stocks of cells for researchers and also establish seed stocks of cell lines for clinical trials. Whilst the Bank is prohibited from carrying out basic stem cell research (to avoid conflicts of interest) it is working to improve stem cell banking procedures including cryopreservation, characterization and quality control. The Bank also supports training activities and has provided the hub for the International Stem Cell Initiative, which includes 17 expert stem cell centers aiming to characterize a large number of human embryonic stem cell lines in a standardized way to improve our understanding of the characteristics of these cells.

Methods for Stem Cell Production and Therapy

NASA Technical Reports Server (NTRS)

Valluri, Jagan V. (Inventor); Claudio, Pier Paolo (Inventor)

2015-01-01

The present invention relates to methods for rapidly expanding a stem cell population with or without culture supplements in simulated microgravity conditions. The present invention relates to methods for rapidly increasing the life span of stem cell populations without culture supplements in simulated microgravity conditions. The present invention also relates to methods for increasing the sensitivity of cancer stem cells to chemotherapeutic agents by culturing the cancer stem cells under microgravity conditions and in the presence of omega-3 fatty acids. The methods of the present invention can also be used to proliferate cancer cells by culturing them in the presence of omega-3 fatty acids. The present invention also relates to methods for testing the sensitivity of cancer cells and cancer stem cells to chemotherapeutic agents by culturing the cancer cells and cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce tissue for use in transplantation by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors to promote differentiation of cancer stem cells under microgravity conditions.

Dental pulp stem cells in regenerative dentistry.

PubMed

Casagrande, Luciano; Cordeiro, Mabel M; Nör, Silvia A; Nör, Jacques E

2011-01-01

Stem cells constitute the source of differentiated cells for the generation of tissues during development, and for regeneration of tissues that are diseased or injured postnatally. In recent years, stem cell research has grown exponentially owing to the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that span from Alzheimer's disease to cardiac ischemia to bone or tooth loss. Growing evidence demonstrates that stem cells are primarily found in niches and that certain tissues contain more stem cells than others. Among these tissues, the dental pulp is considered a rich source of mesenchymal stem cells that are suitable for tissue engineering applications. It is known that dental pulp stem cells have the potential to differentiate into several cell types, including odontoblasts, neural progenitors, osteoblasts, chondrocytes, and adipocytes. The dental pulp stem cells are highly proliferative. This characteristic facilitates ex vivo expansion and enhances the translational potential of these cells. Notably, the dental pulp is arguably the most accessible source of postnatal stem cells. Collectively, the multipotency, high proliferation rates, and accessibility make the dental pulp an attractive source of mesenchymal stem cells for tissue regeneration. This review discusses fundamental concepts of stem cell biology and tissue engineering within the context of regenerative dentistry.

Translating stem cell therapies: the role of companion animals in regenerative medicine

PubMed Central

Volk, Susan W.; Theoret, Christine

2013-01-01

Veterinarians and veterinary medicine have been integral to the development of stem cell therapies. The contributions of large animal experimental models to the development and refinement of modern hematopoietic stem cell transplantation were noted nearly five decades ago. More recent advances in adult stem cell/regenerative cell therapies continue to expand knowledge of the basic biology and clinical applications of stem cells. A relatively liberal legal and ethical regulation of stem cell research in veterinary medicine has facilitated the development and in some instances clinical translation of a variety of cell-based therapies involving hematopoietic (HSC) and mesenchymal stem cells (MSC) as well as other adult regenerative cells and recently embryonic stem cells (ESC) and induced pluripotent stem cells (iPSC). In fact, many of the pioneering developments in these fields of stem cell research have been achieved through collaborations of veterinary and human scientists. This review aims to provide an overview of the contribution of large animal veterinary models in advancing stem cell therapies for both human and clinical veterinary applications. Moreover, in the context of the “One Health Initiative”, the role veterinary patients may play in the future evolution of stem cell therapies for both human and animal patients will be explored. PMID:23627495

Wnt6 maintains anterior escort cells as an integral component of the germline stem cell niche

PubMed Central

2018-01-01

ABSTRACT Stem cells reside in a niche, a local environment whose cellular and molecular complexity is still being elucidated. In Drosophila ovaries, germline stem cells depend on cap cells for self-renewing signals and physical attachment. Germline stem cells also contact the anterior escort cells, and here we report that anterior escort cells are absolutely required for germline stem cell maintenance. When escort cells die from impaired Wnt signaling or hid expression, the loss of anterior escort cells causes loss of germline stem cells. Anterior escort cells function as an integral niche component by promoting DE-cadherin anchorage and by transiently expressing the Dpp ligand to promote full-strength BMP signaling in germline stem cells. Anterior escort cells are maintained by Wnt6 ligands produced by cap cells; without Wnt6 signaling, anterior escort cells die leaving vacancies in the niche, leading to loss of germline stem cells. Our data identify anterior escort cells as constituents of the germline stem cell niche, maintained by a cap cell-produced Wnt6 survival signal. PMID:29361569

Wnt6 maintains anterior escort cells as an integral component of the germline stem cell niche.

PubMed

Wang, Xiaoxi; Page-McCaw, Andrea

2018-02-07

Stem cells reside in a niche, a local environment whose cellular and molecular complexity is still being elucidated. In Drosophila ovaries, germline stem cells depend on cap cells for self-renewing signals and physical attachment. Germline stem cells also contact the anterior escort cells, and here we report that anterior escort cells are absolutely required for germline stem cell maintenance. When escort cells die from impaired Wnt signaling or hid expression, the loss of anterior escort cells causes loss of germline stem cells. Anterior escort cells function as an integral niche component by promoting DE-cadherin anchorage and by transiently expressing the Dpp ligand to promote full-strength BMP signaling in germline stem cells. Anterior escort cells are maintained by Wnt6 ligands produced by cap cells; without Wnt6 signaling, anterior escort cells die leaving vacancies in the niche, leading to loss of germline stem cells. Our data identify anterior escort cells as constituents of the germline stem cell niche, maintained by a cap cell-produced Wnt6 survival signal. © 2018. Published by The Company of Biologists Ltd.

Amoebicidal Activity of Caffeine and Maslinic Acid by the Induction of Programmed Cell Death in Acanthamoeba

PubMed Central

Martín-Navarro, Carmen M.; López-Arencibia, Atteneri; Sifaoui, Ines; Reyes-Batlle, María; Fouque, Emilie; Osuna, Antonio; Valladares, Basilio; Piñero, José E.; Héchard, Yann; Maciver, Sutherland K.

2017-01-01

ABSTRACT Free-living amoebae of the genus Acanthamoeba are the causal agents of a sight-threatening ulceration of the cornea called Acanthamoeba keratitis, as well as the rare but usually fatal disease granulomatous amoebic encephalitis. Although there are many therapeutic options for the treatment of Acanthamoeba infections, they are generally lengthy and/or have limited efficacy. For the best clinical outcome, treatments should target both the trophozoite and the cyst stages, as cysts are known to confer resistance to treatment. In this study, we document the activities of caffeine and maslinic acid against both the trophozoite and the cyst stages of three clinical strains of Acanthamoeba. These drugs were chosen because they are reported to inhibit glycogen phosphorylase, which is required for encystation. Maslinic acid is also reported to be an inhibitor of extracellular proteases, which may be relevant since the protease activities of Acanthamoeba species are correlated with their pathogenicity. We also provide evidence for the first time that both drugs exert their anti-amoebal effects through programmed cell death. PMID:28320723

21st Nantes Actualités Transplantation: "When Stem Cells Meet Immunology".

PubMed

Anegon, Ignacio; Nguyen, Tuan Huy

2017-01-01

"When Stem Cells Meet Immunology" has been the topic of the 21st annual "Nantes Actualités en Transplantation" meeting (June 9-10, 2016, Nantes, France). This meeting brought together pioneers and leading experts in the fields of stem cells, biomaterials and immunoregulation. Presentations covered multipotent (mesenchymal and hematopoietic) and pluripotent stem cells (embryonic and induced) for regenerative medicine of incurable diseases, immunotherapy and blood transfusions. An additional focus had been immune rejections and responses of allogeneic or autologous stem cells. Conversely, stem cells are also able to directly modulate the immune response through the production of immunoregulatory molecules. Moreover, stem cells may also provide an unlimited source of immune cells (DCs, NK cells, B cells, and T cells) that can operate as "super" immune cells, for example, through genetic engineering with chimeric antigen receptors.This meeting report puts presentations into an overall context highlighting new potential biomarkers for potency prediction of mesenchymal stem cell-derived and pluripotent stem cell-derived multicellular organoids. Finally, we propose future directions arising from the flourishing encounter of stem cell and immune biology.

Differential sensitivity of Glioma stem cells to Aurora kinase A inhibitors: implications for stem cell mitosis and centrosome dynamics.

PubMed

Mannino, Mariella; Gomez-Roman, Natividad; Hochegger, Helfrid; Chalmers, Anthony J

2014-07-01

Glioma stem-cell-like cells are considered to be responsible for treatment resistance and tumour recurrence following chemo-radiation in glioblastoma patients, but specific targets by which to kill the cancer stem cell population remain elusive. A characteristic feature of stem cells is their ability to undergo both symmetric and asymmetric cell divisions. In this study we have analysed specific features of glioma stem cell mitosis. We found that glioma stem cells appear to be highly prone to undergo aberrant cell division and polyploidization. Moreover, we discovered a pronounced change in the dynamic of mitotic centrosome maturation in these cells. Accordingly, glioma stem cell survival appeared to be strongly dependent on Aurora A activity. Unlike differentiated cells, glioma stem cells responded to moderate Aurora A inhibition with spindle defects, polyploidization and a dramatic increase in cellular senescence, and were selectively sensitive to Aurora A and Plk1 inhibitor treatment. Our study proposes inhibition of centrosomal kinases as a novel strategy to selectively target glioma stem cells. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Effect of aging on stem cells

PubMed Central

Ahmed, Abu Shufian Ishtiaq; Sheng, Matilda HC; Wasnik, Samiksha; Baylink, David J; Lau, Kin-Hing William

2017-01-01

Pluripotent stem cells have the remarkable self-renewal ability and are capable of differentiating into multiple diverse cells. There is increasing evidence that the aging process can have adverse effects on stem cells. As stem cells age, their renewal ability deteriorates and their ability to differentiate into the various cell types is altered. Accordingly, it is suggested aging-induced deterioration of stem cell functions may play a key role in the pathophysiology of the various aging-associated disorders. Understanding the role of the aging process in deterioration of stem cell function is crucial, not only in understanding the pathophysiology of aging-associated disorders, but also in future development of novel effective stem cell-based therapies to treat aging-associated diseases. This review article first focuses on the basis of the various aging disease-related stem cell dysfunction. It then addresses the several concepts on the potential mechanism that causes aging-related stem cell dysfunction. It also briefly discusses the current potential therapies under development for aging-associated stem cell defects. PMID:28261550

Engineering Stem Cells for Biomedical Applications

PubMed Central

Yin, Perry T.; Han, Edward

2018-01-01

Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer. PMID:25772134

Therapeutic potential of dental stem cells

PubMed Central

Chalisserry, Elna Paul; Nam, Seung Yun; Park, Sang Hyug; Anil, Sukumaran

2017-01-01

Stem cell biology has become an important field in regenerative medicine and tissue engineering therapy since the discovery and characterization of mesenchymal stem cells. Stem cell populations have also been isolated from human dental tissues, including dental pulp stem cells, stem cells from human exfoliated deciduous teeth, stem cells from apical papilla, dental follicle progenitor cells, and periodontal ligament stem cells. Dental stem cells are relatively easily obtainable and exhibit high plasticity and multipotential capabilities. The dental stem cells represent a gold standard for neural-crest-derived bone reconstruction in humans and can be used for the repair of body defects in low-risk autologous therapeutic strategies. The bioengineering technologies developed for tooth regeneration will make substantial contributions to understand the developmental process and will encourage future organ replacement by regenerative therapies in a wide variety of organs such as the liver, kidney, and heart. The concept of developing tooth banking and preservation of dental stem cells is promising. Further research in the area has the potential to herald a new dawn in effective treatment of notoriously difficult diseases which could prove highly beneficial to mankind in the long run. PMID:28616151

Single-cell sequencing in stem cell biology.

PubMed

Wen, Lu; Tang, Fuchou

2016-04-15

Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

The Implications of the Cancer Stem Cell Hypothesis for Neuro-Oncology and Neurology.

PubMed

Rich, Jeremy N

2008-05-01

The cancer stem cell hypothesis posits that cancers contain a subset of neoplastic cells that propagate and maintain tumors through sustained self-renewal and potent tumorigenecity. Recent excitement has been generated by a number of reports that have demonstrated the existence of cancer stem cells in several types of brain tumors. Brain cancer stem cells - also called tumor initiating cells or tumor propagating cells - share features with normal neural stem cells but do not necessarily originate from stem cells. Although most cancers have only a small fraction of cancer stem cells, these tumor cells have been shown in laboratory studies to contribute to therapeutic resistance, formation of new blood vessels to supply the tumor, and tumor spread. As malignant brain tumors rank among the deadliest of all neurologic diseases, the identification of new cellular targets may have profound implications in neuro-oncology. Novel drugs that target stem cell pathways active in brain tumors have been efficacious against cancer stem cells suggesting that anti-cancer stem cell therapies may advance brain tumor therapy. The cancer stem cell hypothesis may have several implications for other neurologic diseases as caution must be exercised in activating stem cell maintenance pathways in cellular therapies for neurodegenerative diseases. The ability for a small fraction of cells to determine the overall course of a disease may also inform new paradigms of disease that may translate into improved patient outcomes.

Early development of the zebrafish pronephros and analysis of mutations affecting pronephric function.

PubMed

Drummond, I A; Majumdar, A; Hentschel, H; Elger, M; Solnica-Krezel, L; Schier, A F; Neuhauss, S C; Stemple, D L; Zwartkruis, F; Rangini, Z; Driever, W; Fishman, M C

1998-12-01

The zebrafish pronephric kidney provides a simplified model of nephron development and epithelial cell differentiation which is amenable to genetic analysis. The pronephros consists of two nephrons with fused glomeruli and paired pronephric tubules and ducts. Nephron formation occurs after the differentiation of the pronephric duct with both the glomeruli and tubules being derived from a nephron primordium. Fluorescent dextran injection experiments demonstrate that vascularization of the zebrafish pronephros and the onset of glomerular filtration occurs between 40 and 48 hpf. We isolated fifteen recessive mutations that affect development of the pronephros. All have visible cysts in place of the pronephric tubule at 2-2.5 days of development. Mutants were grouped in three classes: (1) a group of twelve mutants with defects in body axis curvature and manifesting the most rapid and severe cyst formation involving the glomerulus, tubule and duct, (2) the fleer mutation with distended glomerular capillary loops and cystic tubules, and (3) the mutation pao pao tang with a normal glomerulus and cysts limited to the pronephric tubules. double bubble was analyzed as a representative of mutations that perturb the entire length of the pronephros and body axis curvature. Cyst formation begins in the glomerulus at 40 hpf at the time when glomerular filtration is established suggesting a defect associated with the onset of pronephric function. Basolateral membrane protein targeting in the pronephric duct epithelial cells is also severely affected, suggesting a failure in terminal epithelial cell differentiation and alterations in electrolyte transport. These studies reveal the similarity of normal pronephric development to kidney organogenesis in all vertebrates and allow for a genetic dissection of genes needed to establish the earliest renal function.

The immunoprofile of odontogenic keratocyst (keratocystic odontogenic tumor) that includes expression of PTCH, SMO, GLI-1 and bcl-2 is similar to ameloblastoma but different from odontogenic cysts.

PubMed

Vered, M; Peleg, O; Taicher, S; Buchner, A

2009-08-01

The aggressive biological behavior of odontogenic keratocysts (OKCs), unlike that of other odontogenic cysts, has argued for its recent re-classification as a neoplasm, 'keratocystic odontogenic tumor'. Identification of mutations in the PTCH gene in some of the OKCs that were expected to produce truncated proteins, resulting in loss of control of the cell cycle, provided additional support for OKCs having a neoplastic nature. We investigated the immunohistochemical expression of the sonic hedgehog (SHH) signaling pathway-related proteins, PTCH, smoothened (SMO) and GLI-1, and of the SHH-induced bcl-2 oncoprotein in a series of primary OKC (pOKC), recurrent OKC (rOKC) and nevoid basal cell carcinoma syndrome-associated OKCs (NBCCS-OKCs), and compared them to solid ameloblastomas (SAMs), unicystic ameloblastomas (UAMs), 'orthokeratinized' OKCs (oOKCs), dentigerous cysts (DCs) and radicular cysts (RCs). All studied lesions expressed the SHH pathway-related proteins in a similar pattern. The expression of bcl-2 in OKCs (pOKCs and NBCCS-OKCs) and SAMs was significantly higher than in oOKCs, DCs and RCs (P < 0.001). The present results of the immunoprofile of OKCs (that includes the expression of the SHH-related proteins and the SHH-induced bcl-2 oncoprotein) further support the notion of OKC having a neoplastic nature. As OKCs vary considerably in their biologic behavior, it is suggested that the quality and quantity of interactions between the SHH and other cell cycle regulatory pathways are likely to work synergistically to define the individual phenotype and corresponding biological behavior of this lesion.

Can bone marrow differentiate into renal cells?

PubMed

Imai, Enyu; Ito, Takahito

2002-10-01

A considerable plasticity of adult stem cells has been confirmed in a wide variety of tissues. In particular, the pluripotency of bone marrow-derived stem cells may influence the regeneration of injured tissues and may provide novel avenues in regenerative medicine. Bone marrow contains at least hematopoietic and mesenchymal stem cells, and both can differentiate into a wide range of differentiated cells. Side population (SP) cells, which are originally defined in bone marrow cells by high efflux of DNA-binding dye, seem to be a new class of multipotent stem cells. Irrespective of the approach used to obtain stem cells, the fates of marrow-derived cells following bone marrow transplantation can be traced by labeling donor cells with green fluorescence protein or by identifying donor Y chromosome in female recipients. So far, bone marrow-derived cells have been reported to differentiate into renal cells, including mesangial cells, endothelial cells, podocytes, and tubular cells in the kidney, although controversy exists. Further studies are required to address this issue. Cell therapy will be promising when we learn to control stem cells such as bone marrow-derived stem cells, embryonic stem cells, and resident stem cells in the kidney. Identification of factors that support stem cells or promote their differentiation should provide a relevant step towards cell therapy.

Modeling Alveolar Epithelial Cell Behavior In Spatially Designed Hydrogel Microenvironments

NASA Astrophysics Data System (ADS)

Lewis, Katherine Jean Reeder

The alveolar epithelium consists of two cell phenotypes, elongated alveolar type I cells (AT1) and rounded alveolar type II cells (ATII), and exists in a complex three-dimensional environment as a polarized cell layer attached to a thin basement membrane and enclosing a roughly spherical lumen. Closely surrounding the alveolar cysts are capillary endothelial cells as well as interstitial pulmonary fibroblasts. Many factors are thought to influence alveolar epithelial cell differentiation during lung development and wound repair, including physical and biochemical signals from the extracellular matrix (ECM), and paracrine signals from the surrounding mesenchyme. In particular, disrupted signaling between the alveolar epithelium and local fibroblasts has been implicated in the progression of several pulmonary diseases. However, given the complexity of alveolar tissue architecture and the multitude of signaling pathways involved, designing appropriate experimental platforms for this biological system has been difficult. In order to isolate key factors regulating cellular behavior, the researcher ideally should have control over biophysical properties of the ECM, as well as the ability to organize multiple cell types within the scaffold. This thesis aimed to develop a 3D synthetic hydrogel platform to control alveolar epithelial cyst formation, which could then be used to explore how extracellular cues influence cell behavior in a tissue-relevant cellular arrangement. To accomplish this, a poly(ethylene glycol) (PEG) hydrogel network containing enzymatically-degradable crosslinks and bioadhesive pendant peptides was employed as a base material for encapsulating primary alveolar epithelial cells. First, an array of microwells of various cross-sectional shapes was photopatterned into a PEG gel containing photo-labile crosslinks, and primary ATII cells were seeded into the wells to examine the role of geometric confinement on differentiation and multicellular arrangement. Aggregate formation in these microwells motivated us to develop a templating technique to create hollow cyst-like epithelial structures within PEG hydrogels. Photodegradable microspheres were used to form spherical epithelial layers, which were then encapsulated in a PEG hydrogel followed by template erosion with cytocompatible light. With these model alveoli, we investigated the interplay between the epithelium and mesenchyme by co-encapsulating healthy and diseased pulmonary fibroblasts with healthy and diseased epithelial cysts and measuring important cellular behaviors (i.e. proliferation, migration, and protein expression). This model of alveolar tissue represents a significant advance in culture platforms available to researchers interested in identifying the mechanisms involved in disease progression and for testing potential therapeutics in a controlled, tissue-appropriate setting.

[The emerging technology of tissue engineering : Focus on stem cell niche].

PubMed

Schlötzer-Schrehardt, U; Freudenberg, U; Kruse, F E

2017-04-01

Limbal stem cells reside in a highly specialized complex microenvironment that is known as the stem cell niche, an anatomically protected region at the bottom of the Palisades of Vogt, where the stem cells are located and where their quiescence, proliferation and differentiation are maintained in balance. Besides the epithelial stem and progenitor cell clusters, the limbal niche comprises several types of supporting niche cells and a specific extracellular matrix mediating biochemical and biophysical signals. Stem cell-based tissue engineering aims to mimic the native stem cell niche and to present appropriate microenvironmental cues in a controlled and reproducible fashion in order to maintain stem cell function within the graft. Current therapeutic approaches for ex vivo expansion of limbal stem cells only take advantage of surrogate niches. However, new insights into the molecular composition of the limbal niche and innovative biosynthetic scaffolds have stimulated novel strategies for niche-driven stem cell cultivation. Promising experimental approaches include collagen-based organotypic coculture systems of limbal epithelial stem cells with their niche cells and biomimetic hydrogel platforms prefunctionalized with appropriate biomolecular and biophysical signals. Future translation of these novel regenerative strategies into clinical application is expected to improve long-term outcomes of limbal stem cell transplantation for ocular surface reconstruction.

Combination cell therapy with mesenchymal stem cells and neural stem cells for brain stroke in rats.

PubMed

Hosseini, Seyed Mojtaba; Farahmandnia, Mohammad; Razi, Zahra; Delavari, Somayeh; Shakibajahromi, Benafsheh; Sarvestani, Fatemeh Sabet; Kazemi, Sepehr; Semsar, Maryam

2015-05-01

Brain stroke is the second most important events that lead to disability and morbidity these days. Although, stroke is important, there is no treatment for curing this problem. Nowadays, cell therapy has opened a new window for treating central nervous system disease. In some previous studies the Mesenchymal stem cells and neural stem cells. In this study, we have designed an experiment to assess the combination cell therapy (Mesenchymal and Neural stem cells) effects on brain stroke. The Mesenchymal stem cells were isolated from adult rat bone marrow and the neural stem cells were isolated from ganglion eminence of rat embryo 14 days. The Mesenchymal stem cells were injected 1 day after middle cerebral artery occlusion (MCAO) and the neural stem cells transplanted 7 day after MCAO. After 28 days, the neurological outcomes and brain lesion volumes were evaluated. Also, the activity of Caspase 3 was assessed in different groups. The group which received combination cell therapy had better neurological examination and less brain lesion. Also the combination cell therapy group had the least Caspase 3 activity among the groups. The combination cell therapy is more effective than Mesenchymal stem cell therapy and neural stem cell therapy separately in treating the brain stroke in rats.

Application of Stem Cells in Oral Disease Therapy: Progresses and Perspectives

PubMed Central

Yang, Bo; Qiu, Yi; Zhou, Niu; Ouyang, Hong; Ding, Junjun; Cheng, Bin; Sun, Jianbo

2017-01-01

Stem cells are undifferentiated and pluripotent cells that can differentiate into specialized cells with a more specific function. Stem cell therapies become preferred methods for the treatment of multiple diseases. Oral and maxillofacial defect is one kind of the diseases that could be most possibly cured by stem cell therapies. Here we discussed oral diseases, oral adult stem cells, iPS cells, and the progresses/challenges/perspectives of application of stem cells for oral disease treatment. PMID:28421002

Diploid, but not haploid, human embryonic stem cells can be derived from microsurgically repaired tripronuclear human zygotes

PubMed Central

Fan, Yong; Li, Rong; Huang, Jin; Yu, Yang; Qiao, Jie

2013-01-01

Human embryonic stem cells have shown tremendous potential in regenerative medicine, and the recent progress in haploid embryonic stem cells provides new insights for future applications of embryonic stem cells. Disruption of normal fertilized embryos remains controversial; thus, the development of a new source for human embryonic stem cells is important for their usefulness. Here, we investigated the feasibility of haploid and diploid embryo reconstruction and embryonic stem cell derivation using microsurgically repaired tripronuclear human zygotes. Diploid and haploid zygotes were successfully reconstructed, but a large proportion of them still had a tripolar spindle assembly. The reconstructed embryos developed to the blastocyst stage, although the loss of chromosomes was observed in these zygotes. Finally, triploid and diploid human embryonic stem cells were derived from tripronuclear and reconstructed zygotes (from which only one pronucleus was removed), but haploid human embryonic stem cells were not successfully derived from the reconstructed zygotes when two pronuclei were removed. Both triploid and diploid human embryonic stem cells showed the general characteristics of human embryonic stem cells. These results indicate that the lower embryo quality resulting from abnormal spindle assembly contributed to the failure of the haploid embryonic stem cell derivation. However, the successful derivation of diploid embryonic stem cells demonstrated that microsurgical tripronuclear zygotes are an alternative source of human embryonic stem cells. In the future, improving spindle assembly will facilitate the application of triploid zygotes to the field of haploid embryonic stem cells. PMID:23255130

The study of apoptotic bifunctional effects in relationship between host and parasite in cystic echinococcosis: a new approach to suppression and survival of hydatid cyst.

PubMed

Spotin, Adel; Majdi, Monireh Mokhtari Amir; Sankian, Mojtaba; Varasteh, Abdolreza

2012-05-01

Cystic echinococcosis (hydatidosis) is a zoonotic helminthic disease of human and other intermediated hosts wherein infection is caused by the larval stages of tapeworm Echinococcus granulosus. Growth of the larval stage is formed throughout the internal organs, the liver and lung, causing their destruction. Important pathways are unknown about suppression and survival of cysts in human body. In this study, apoptotic bifunctional effects are evaluated in relationship between host and parasite in cystic echinococcosis. Human lymphocytes were treated with hydatid fluid (HF). After 6 h of exposure, caspase-3 activity was measured by fluorometric assay in the HF-treated lymphocytes and control cells. Also, the expression of Bax (as pro-apoptotic protein) and Bcl-2 (an anti-apoptotic protein) mRNA was assessed by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) after 12 h of exposure. For surveying of apoptosis-inducing ligands TNF-related apoptosis-inducing ligand and Fas-L, germinal layer and accompaniment peripheral tissues as healthy control were separated by scalpel from each cyst in sterile condition, then were assess by semiquantitative RT-PCR method in mRNA expression. Both the ratio of Bax/Bcl-2 mRNA expression and caspase-3 activity were higher in the fertile fluid-treated lymphocytes relative to infertile fluid-treated lymphocytes and control group versus the expression level of apoptosis-inducing ligands having a relatively high level in germinal layer of infertile cyst in comparison to fertile cyst and healthy tissue. Apoptosis of germinal layer of fertile cysts is possibly one of the suppression mechanisms in hydatidosis patients, in contrast to lymphocytes apoptosis by modulator of hydatid fluid, one of the hydatid cyst survival mechanisms.

BRAFV600E mutation in the diagnosis of unicystic ameloblastoma.

PubMed

Pereira, Núbia Braga; Pereira, Karuza Maria Alves; Coura, Bruna Pizziolo; Diniz, Marina Gonçalves; de Castro, Wagner Henriques; Gomes, Carolina Cavalieri; Gomez, Ricardo Santiago

2016-11-01

Unicystic ameloblastoma, an odontogenic neoplasm, presents clinical and radiographic similarities with dentigerous and radicular cysts, non-neoplastic lesions. It is not always possible to reach a final diagnosis with the incisional biopsy, leading to inappropriate treatment. The BRAFV600E activating mutation has been reported in a high proportion of ameloblastomas. The purpose of the study was to assess the utility of the detection of the BRAFV600E mutation in the differential diagnosis of unicystic ameloblastoma with dentigerous and radicular cysts. Twenty-six archival samples were included, comprising eight unicystic ameloblastomas (UAs), nine dentigerous and nine radicular cysts. The mutation was assessed in all samples by anti-BRAFV600E (clone VE1) immunohistochemistry (IHC) and by TaqMan mutation detection qPCR assay. Sanger sequencing was further carried out when samples showed conflicting results in the IHC and qPCR. Although all UAs (8/8) showed positive uniform BRAFV600E staining along the epithelial lining length, the mutation was not confirmed by qPCR and Sanger sequencing in three samples. Positive staining for the BRAFV600E protein was observed in one dentigerous cyst, but it was not confirmed by the molecular methods. Furthermore, 2/9 dentigerous cysts and 2/9 radicular cysts showed non-specific immunostaining of the epithelium or plasma cells. None of the dentigerous or radicular cysts cases presented the BRAFV600E mutation in the qPCR assay. The BRAFV600E antibody (clone VE1) IHC may show non-specific staining, but molecular assays may be useful for the diagnosis of unicystic ameloblastoma, in conjunction with clinical, radiological and histopathological features. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effect of parasitic infection on dopamine biosynthesis in dopaminergic cells

PubMed Central

Martin, H.L.; Alsaady, I.; Howell, G.; Prandovszky, E.; Peers, C.; Robinson, P.; McConkey, G.A.

2015-01-01

Infection by the neurotropic agent Toxoplasma gondii alters rodent behavior and can result in neuropsychiatric symptoms in humans. Little is understood regarding the effects of infection on host neural processes but alterations to dopaminergic neurotransmission are implicated. We have previously reported elevated levels of dopamine (DA) in infected dopaminergic cells however the involvement of the host enzymes and fate of the produced DA were not defined. In order to clarify the effects of infection on host DA biosynthetic enzymes and DA packaging we examined enzyme levels and activity and DA accumulation and release in T. gondii-infected neurosecretory cells. Although the levels of the host tyrosine hydroxylase (TH) and DOPA decarboxylase and AADC (DDC) did not change significantly in infected cultures, DDC was found within the parasitophorous vacuole (PV), the vacuolar compartment where the parasites reside, as well as in the host cytosol in infected dopaminergic cells. Strikingly, DDC was found within the intracellular parasite cysts in infected brain tissue. This finding could provide some explanation for observations of DA within tissue cysts in infected brain as a parasite-encoded enzyme with TH activity was also localized within tissue cysts. In contrast, cellular DA packaging appeared unchanged in single-cell microamperometry experiments and only a fraction of the increased DA was accessible to high potassium-induced release. This study provides some understanding of how this parasite produces elevated DA within dopaminergic cells without the toxic ramifications of free cytosolic DA. The mechanism for synthesis and packaging of DA by T. gondii-infected dopaminergic cells may have important implications for the effects of chronic T. gondii infection on humans and animals. PMID:26297895

Nano scaffolds and stem cell therapy in liver tissue engineering

NASA Astrophysics Data System (ADS)

Montaser, Laila M.; Fawzy, Sherin M.

2015-08-01

Tissue engineering and regenerative medicine have been constantly developing of late due to the major progress in cell and organ transplantation, as well as advances in materials science and engineering. Although stem cells hold great potential for the treatment of many injuries and degenerative diseases, several obstacles must be overcome before their therapeutic application can be realized. These include the development of advanced techniques to understand and control functions of micro environmental signals and novel methods to track and guide transplanted stem cells. A major complication encountered with stem cell therapies has been the failure of injected cells to engraft to target tissues. The application of nanotechnology to stem cell biology would be able to address those challenges. Combinations of stem cell therapy and nanotechnology in tissue engineering and regenerative medicine have achieved significant advances. These combinations allow nanotechnology to engineer scaffolds with various features to control stem cell fate decisions. Fabrication of Nano fiber cell scaffolds onto which stem cells can adhere and spread, forming a niche-like microenvironment which can guide stem cells to proceed to heal damaged tissues. In this paper, current and emergent approach based on stem cells in the field of liver tissue engineering is presented for specific application. The combination of stem cells and tissue engineering opens new perspectives in tissue regeneration for stem cell therapy because of the potential to control stem cell behavior with the physical and chemical characteristics of the engineered scaffold environment.

Stem-Cell-Based Tumorigenesis in Adult Drosophila.

PubMed

Hou, S X; Singh, S R

2017-01-01

Recent studies suggest that a small subset of cells within a tumor, the so-called cancer stem cells (CSCs), are responsible for tumor propagation, relapse, and the eventual death of most cancer patients. CSCs may derive from a few tumor-initiating cells, which are either transformed normal stem cells or reprogrammed differentiated cells after acquiring initial cancer-causing mutations. CSCs and normal stem cells share some properties, but CSCs differ from normal stem cells in their tumorigenic ability. Notably, CSCs are usually resistant to chemo- and radiation therapies. Despite the apparent roles of CSCs in human cancers, the biology underlying their behaviors remains poorly understood. Over the past few years, studies in Drosophila have significantly contributed to this new frontier of cancer research. Here, we first review how stem-cell tumors are initiated and propagated in Drosophila, through niche appropriation in the posterior midgut and through stem-cell competition for niche occupancy in the testis. We then discuss the differences between normal and tumorigenic stem cells, revealed by studying Ras V12 -transformed stem-cell tumors in the Drosophila kidney. Finally, we review the biology behind therapy resistance, which has been elucidated through studies of stem-cell resistance and sensitivity to death inducers using female germline stem cells and intestinal stem cells of the posterior midgut. We expect that screens using adult Drosophila neoplastic stem-cell tumor models will be valuable for identifying novel and effective compounds for treating human cancers. © 2017 Elsevier Inc. All rights reserved.

Stem cells with potential to generate insulin producing cells in man.

PubMed

Zulewski, Henryk

2006-10-14

Replacement of insulin-producing cells represents an almost ideal treatment for patients with diabetes mellitus type 1. Transplantation of pancreatic islets of Langerhans--although successful in experienced centres--is limited by the lack of donor organs. Generation of insulin-producing cells from stem cells represents an attractive alternative. Stem cells with the potential to differentiate into insulin-producing cells include embryonic stem cells (ESC) as well as adult stem cells from various tissues including the pancreas, liver, central nervous system, bone marrow and adipose tissue. The use of human ESC is hampered by ethical concerns and the inability to create patient specific ESC with therapeutic cloning. Among adult stem cells mesenchymal stem cells appear to have a particular developmental plasticity ex vivo that include their ability to adopt a pancreatic endocrine phenotype. The present review summarises the current knowledge on the development of insulin-producing cells from stem cells with special emphasis on human mesenchymal stem cells isolated from the pancreas and adipose tissue.

Stem cells with potential to generate insulin-producing cells in man.

PubMed

Zulewski, Henryk

2007-03-02

Replacement of insulin-producing cells represents an almost ideal treatment for patients with diabetes mellitus type 1. Transplantation of pancreatic islets of Langerhans--although successful in experienced centres--is limited by the lack of donor organs. Generation of insulin-producing cells from stem cells represents an attractive alternative. Stem cells with the potential to differentiate into insulin-producing cells include embryonic stem cells (ESC) as well as adult stem cells from various tissues including the pancreas, liver, central nervous system, bone marrow and adipose tissue. The use of human ESC is hampered by ethical concerns and the inability to create patient specific ESC with therapeutic cloning. Among adult stem cells mesenchymal stem cells appear to have a particular developmental plasticity ex vivo that include their ability to adopt a pancreatic endocrine phenotype. The present review summarises the current knowledge on the development of insulin-producing cells from stem cells with special emphasis on human mesenchymal stem cells isolated from the pancreas and adipose tissue.

Mechanical forces direct stem cell behaviour in development and regeneration

PubMed Central

Vining, Kyle H.; Mooney, David J.

2018-01-01

Stem cells and their local microenvironment, or niche, communicate through mechanical, cues to regulate cell fate and cell behaviour, and to guide developmental processes. During embryonic development, mechanical forces are involved in patterning and organogenesis. The physical environment of pluripotent stem cells regulates their differentiation and self-renewal. Mechanical and physical cues are also important in adult tissues, where adult stem cells require physical interactions with the extracellular matrix to maintain their potency. In vitro, synthetic models of the stem cell niche can be used to precisely control and manipulate the biophysical and biochemical properties of the stem cell microenvironment and examine how the mode and magnitude of mechanical cues, such as matrix stiffness or applied forces, direct stem cell differentiation and function. Fundamental insights on the mechanobiology of stem cells also inform the design of artificial niches to support stem cells for regenerative therapies. PMID:29115301

Recent Advances towards the Clinical Application of Stem Cells for Retinal Regeneration

PubMed Central

Becker, Silke; Jayaram, Hari; Limb, G. Astrid

2012-01-01

Retinal degenerative diseases constitute a major cause of irreversible blindness in the world. Stem cell-based therapies offer hope for these patients at risk of or suffering from blindness due to the deterioration of the neural retina. Various sources of stem cells are currently being investigated, ranging from human embryonic stem cells to adult-derived induced pluripotent stem cells as well as human Müller stem cells, with the first clinical trials to investigate the safety and tolerability of human embryonic stem cell-derived retinal pigment epithelium cells having recently commenced. This review aims to summarize the latest advances in the development of stem cell strategies for the replacement of retinal neurons and their supportive cells, the retinal pigment epithelium (RPE) affected by retinal degenerative conditions. Particular emphasis will be given to the advances in stem cell transplantation and the challenges associated with their translation into clinical practice. PMID:24710533

Anomalous optic discs in a patient with a Dandy-Walker cyst.

PubMed

Orcutt, J C; Bunt, A H

1982-03-01

A 19-month-old female infant with a Dandy-Walker cyst had anomalous optic discs, each of which appeared to divide to form an accessory optic nerve. The discs probably lie within the spectrum of anomalous discs including optic nerve aplasia and hypoplasia, megallopapillae, morning glory disc, optic disc dysplasia, and optic nerve colobomas. The association of anomalous optic discs with a Dandy-Walker cyst has not been previously recognized. The ocular and brain malformations in this patient likely occurred during the fourth to eighth week of gestation, when the retinal ganglion cell axons were penetrating the optic nerve, and the rhombic lips were enlarging in early cerebellar development. The etiology of these anomalies is not known; however, teratogens, sporadic events, and genetic disorders should be considered.

Stem-Cell Therapy Advances in China.

PubMed

Hu, Lei; Zhao, Bin; Wang, Songlin

2018-02-01

Stem-cell therapy is a promising method for treating patients with a wide range of diseases and injuries. Increasing government funding of scientific research has promoted rapid developments in stem-cell research in China, as evidenced by the substantial increase in the number and quality of publications in the past 5 years. Multiple high-quality studies have been performed in China that concern cell reprogramming, stem-cell homeostasis, gene modifications, and immunomodulation. The number of translation studies, including basic and preclinical investigations, has also increased. Around 100 stem-cell banks have been established in China, 10 stem-cell drugs are currently in the approval process, and >400 stem cell-based clinical trials are currently registered in China. With continued state funding, advanced biotechnical support, and the development of regulatory standards for the clinical application of stem cells, further innovations are expected that will lead to a boom in stem-cell therapies. This review highlights recent achievements in stem-cell research in China and discusses future prospects.

New insights into mechanisms of stem cell daughter fate determination in regenerative tissues.

PubMed

Sada, Aiko; Tumbar, Tudorita

2013-01-01

Stem cells can self-renew and differentiate over extended periods of time. Understanding how stem cells acquire their fates is a central question in stem cell biology. Early work in Drosophila germ line and neuroblast showed that fate choice is achieved by strict asymmetric divisions that can generate each time one stem and one differentiated cell. More recent work suggests that during homeostasis, some stem cells can divide symmetrically to generate two differentiated cells or two identical stem cells to compensate for stem cell loss that occurred by direct differentiation or apoptosis. The interplay of all these factors ensures constant tissue regeneration and the maintenance of stem cell pool size. This interplay can be modeled as a population-deterministic dynamics that, at least in some systems, may be described as stochastic behavior. Here, we overview recent progress made on the characterization of stem cell dynamics in regenerative tissues. Copyright © 2013 Elsevier Inc. All rights reserved.

Selection of Phage Display Peptides Targeting Human Pluripotent Stem Cell-Derived Progenitor Cell Lines.

PubMed

Bignone, Paola A; Krupa, Rachel A; West, Michael D; Larocca, David

2016-01-01

The ability of human pluripotent stem cells (hPS) to both self-renew and differentiate into virtually any cell type makes them a promising source of cells for cell-based regenerative therapies. However, stem cell identity, purity, and scalability remain formidable challenges that need to be overcome for translation of pluripotent stem cell research into clinical applications. Directed differentiation from hPS cells is inefficient and residual contamination with pluripotent cells that have the potential to form tumors remains problematic. The derivation of scalable (self-renewing) embryonic progenitor stem cell lines offers a solution because they are well defined and clonally pure. Clonally pure progenitor stem cell lines also provide a means for identifying cell surface targeting reagents that are useful for identification, tracking, and repeated derivation of the corresponding progenitor stem cell types from additional hPS cell sources. Such stem cell targeting reagents can then be applied to the manufacture of genetically diverse banks of human embryonic progenitor cell lines for drug screening, disease modeling, and cell therapy. Here we present methods to identify human embryonic progenitor stem cell targeting peptides by selection of phage display libraries on clonal embryonic progenitor cell lines and demonstrate their use for targeting quantum dots (Qdots) for stem cell labeling.

Extinction models for cancer stem cell therapy

PubMed Central

Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S.; Lange, Kenneth L.

2012-01-01

Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth–death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives. PMID:22001354

Extinction models for cancer stem cell therapy.

PubMed

Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S; Lange, Kenneth L

2011-12-01

Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth-death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives. Copyright © 2011 Elsevier Inc. All rights reserved.

Significant Reduction of Brain Cysts Caused by Toxoplasma gondii after Treatment with Spiramycin Coadministered with Metronidazole in a Mouse Model of Chronic Toxoplasmosis

PubMed Central

Chew, Wai Kit; Ambu, Stephen; Mak, Joon Wah

2012-01-01

Toxoplasma gondii is a parasite that generates latent cysts in the brain; reactivation of these cysts may lead to fatal toxoplasmic encephalitis, for which treatment remains unsuccessful. We assessed spiramycin pharmacokinetics coadministered with metronidazole, the eradication of brain cysts and the in vitro reactivation. Male BALB/c mice were fed 1,000 tachyzoites orally to develop chronic toxoplasmosis. Four weeks later, infected mice underwent different treatments: (i) infected untreated mice (n = 9), which received vehicle only; (ii) a spiramycin-only group (n = 9), 400 mg/kg daily for 7 days; (iii) a metronidazole-only group (n = 9), 500 mg/kg daily for 7 days; and (iv) a combination group (n = 9), which received both spiramycin (400 mg/kg) and metronidazole (500 mg/kg) daily for 7 days. An uninfected control group (n = 10) was administered vehicle only. After treatment, the brain cysts were counted, brain homogenates were cultured in confluent Vero cells, and cysts and tachyzoites were counted after 1 week. Separately, pharmacokinetic profiles (plasma and brain) were assessed after a single dose of spiramycin (400 mg/kg), metronidazole (500 mg/kg), or both. Metronidazole treatment increased the brain spiramycin area under the concentration-time curve from 0 h to ∞ (AUC0–∞) by 67% without affecting its plasma disposition. Metronidazole plasma and brain AUC0–∞ values were reduced 9 and 62%, respectively, after spiramycin coadministration. Enhanced spiramycin brain exposure after coadministration reduced brain cysts 15-fold (79 ± 23 for the combination treatment versus 1,198 ± 153 for the untreated control group [P < 0.05]) and 10-fold versus the spiramycin-only group (768 ± 125). Metronidazole alone showed no effect (1,028 ± 149). Tachyzoites were absent in the brain. Spiramycin reduced in vitro reactivation. Metronidazole increased spiramycin brain penetration, causing a significant reduction of T. gondii brain cysts, with potential clinical translatability for chronic toxoplasmosis treatment. PMID:22271863

Post-treatment Vascular Leakage and Inflammatory Responses around Brain Cysts in Porcine Neurocysticercosis

PubMed Central

Mahanty, Siddhartha; Orrego, Miguel Angel; Mayta, Holger; Marzal, Miguel; Cangalaya, Carla; Paredes, Adriana; Gonzales-Gustavson, Eloy; Arroyo, Gianfranco; Gonzalez, Armando E.; Guerra-Giraldez, Cristina; García, Hector H.; Nash, Theodore E.

2015-01-01

Cysticidal treatment of neurocysticercosis, an infection of humans and pig brains with Taenia solium, results in an early inflammatory response directed to cysts causing seizures and focal neurological manifestations. Treatment-induced pericystic inflammation and its association with blood brain barrier (BBB) dysfunction, as determined by Evans blue (EB) extravasation, was studied in infected untreated and anthelmintic-treated pigs. We compared the magnitude and extent of the pericystic inflammation, presence of EB-stained capsules, the level of damage to the parasite, expression of genes for proinflammatory and regulatory cytokines, chemokines, and tissue remodeling by quantitative PCR assays between treated and untreated infected pigs and between EB-stained (blue) and non stained (clear) cysts. Inflammatory scores were higher in pericystic tissues from EB-stained cysts compared to clear cysts from untreated pigs and also from anthelmintic-treated pigs 48 hr and 120 hr after treatment. The degree of inflammation correlated with the severity of cyst wall damage and both increased significantly at 120 hours. Expression levels of the proinflammatory genes for IL-6, IFN-γ, TNF-α were higher in EB-stained cysts compared to clear cysts and unaffected brain tissues, and were generally highest at 120 hr. Additionally, expression of some markers of immunoregulatory activity (IL-10, IL-2Rα) were decreased in EB-stained capsules. An increase in other markers for regulatory T cells (CTLA4, FoxP3) was found, as well as significant increases in expression of two metalloproteases, MMP1 and MMP2 at 48 hr and 120 hr post-treatment. We conclude that the increase in severity of the inflammation caused by treatment is accompanied by both a proinflammatory and a complex regulatory response, largely limited to pericystic tissues with compromised vascular integrity. Because treatment induced inflammation occurs in porcine NCC similar to that in human cases, this model can be used to investigate mechanisms involved in host damaging inflammatory responses and agents or modalities that may control damaging post treatment inflammation. PMID:25774662

Aging and stem cell therapy: AMPK as an applicable pharmacological target for rejuvenation of aged stem cells and achieving higher efficacy in stem cell therapy.

PubMed

Khorraminejad-Shirazi, Mohammadhossein; Farahmandnia, Mohammad; Kardeh, Bahareh; Estedlal, Alireza; Kardeh, Sina; Monabati, Ahmad

2017-10-19

In recent years, tissue regeneration has become a promising field for developing stem cell-based transplantation therapies for human patients. Adult stem cells are affected by the same aging mechanisms that involve somatic cells. One of the mechanisms involved in cellular aging is hyperactivation of mechanistic target of rapamycin complex 1 (mTORC1) and disruption of 5' adenosine monophosphate-activated protein kinase (AMPK). Aging of stem cells results in their impaired regenerative capacity and depletion of stem cell pools in adult tissue, which results in lower efficacy of stem cell therapy. By utilizing an effective therapeutic intervention for aged stem cells, stem cell therapy can become more promising for future application. mTORC1 inhibition is a practical approach to preserve the stem cell pool. In this article, we review the dynamic interaction between sirtuin (silent mating type information regulation 2 homolog) 1, AMPK, and mTORC1. We propose that using AMPK activators such as 5-aminoimidazole-4-carboxamide ribonucleotide, A769662, metformin, and oxidized nicotinamide adenine dinucleotide (NAD + ) are practical ways to be employed for achieving better optimized results in stem cell-based transplantation therapies. Copyright © 2017 King Faisal Specialist Hospital & Research Centre. Published by Elsevier B.V. All rights reserved.

Stemness of spermatogonial stem cells encapsulated in alginate hydrogel during cryopreservation.

PubMed

Pirnia, A; Parivar, K; Hemadi, M; Yaghmaei, P; Gholami, M

2017-06-01

This study investigated the effect of spermatogonial stem cell encapsulated in alginate hydrogel during cryopreservation, as cells were protected against damage during cryopreservation within the hydrogel. Spermatogonial stem cells were isolated from the testes of Balb/c mice pups (6 days old), purified in laminin-coated dishes and CD90.1 microbeads, encapsulated in alginate hydrogel and then cryopreserved. After thawing, cell viability and Spermatogonial stem cell (SSC) colony diameter were evaluated. After RNA was isolated and cDNA was synthesised, the expression of stemness genes was considered using RT real-time PCR. Finally, spermatogonial stem cells labelled with BrdU were transplanted to busulfan azoospermic mouse models. Lin28a and Sall4 genes were significantly upregulated after cryopreservation in alginate hydrogel. However, cell viability was significantly decreased. The diameter of colonies consisting of spermatogonial stem cells freeze-thawed in alginate microbeads showed no significant difference with fresh spermatogonial stem cells and the control group. The injection of freeze-thawed spermatogonial stem cells encapsulated in alginate hydrogel resulted in spermatogenesis recovery. Alginate mimics the extracellular matrices (ECM) for spermatogonial stem cells; therefore, it can support stemness potential during the cell cryopreservation process and restart spermatogenesis after transplantation. © 2016 Blackwell Verlag GmbH.

Normal and cancer mammary stem cells evade interferon-induced constraint through the miR-199a-LCOR Axis

PubMed Central

Celià-Terrassa, Toni; Liu, Daniel; Choudhury, Abrar; Hang, Xiang; Wei, Yong; Zamalloa, Jose; Alfaro-Aco, Raymundo; Chakrabarti, Rumela; Jiang, Yi-Zhou; Koh, Bong Ihn; Smith, Heath; DeCoste, Christina; Li, Jun-Jing; Shao, Zhi-Ming; Kang, Yibin

2017-01-01

Tumor-initiating cells (TICs), or cancer stem cells (CSC), possess stem cell-like properties observed in normal adult tissue stem cells. Normal and cancerous stem cells may therefore share regulatory mechanisms for maintaining self-renewing capacity and resisting differentiation elicited by cell-intrinsic or microenvironmental cues. Here, we show that miR-199a promotes stem cell properties in mammary stem cells (MaSCs) and breast CSCs by directly repressing nuclear receptor corepressor LCOR, which primes interferon (IFN) responses. Elevated miR-199a expression in stem cell-enriched populations protects normal and malignant stem-like cells from differentiation and senescence induced by IFNs that are produced by epithelial and immune cells in the mammary gland. Importantly, the miR-199a-LCOR-IFN axis is activated in poorly differentiated ER− breast tumors, functionally promotes tumor initiation and metastasis, and is associated with poor clinical outcome. Our study therefore reveals a common mechanism shared by normal and malignant stem cells to protect them from suppressive immune cytokine signaling. PMID:28530657

The Role of Epithelial-Mesenchymal Transition in the Formation of Normal and Neoplastic Mammary Epithelial Stem Cells

DTIC Science & Technology

2011-09-01

separating stem cell and non- stem cell populations of normal and breast cancer cells and identified EMT transcription factors most likely involved in... stem cell biology. Preliminary results directly demonstrate that transient induction of EMT increases the number of mammary epithelial stem cells...EMT and entrance into a stem - cell state. The outcome of these experiments holds important implications for the mechanisms controlling the formation of

Role of the Stem Cell Niche in Hormone-Induced Tumorigenesis in Fetal Mouse Mammary Epithelium

DTIC Science & Technology

2005-08-01

responsive, self renewing and pluripotent. A structure specialized to contain and regulate stem cell activity has been structurally and molecularly...described in Drosophila and some mammalian tissues. The structure, the stem cell niche, functions to 1) shield the stem cell from the burden of incoming...directing stem cell renewal and maturation, 3) prevent stem cells from wandering through the tissue and producing new cells inappropriately, 4) prevent

The Effect of Laser Irradiation on Adipose Derived Stem Cell Proliferation and Differentiation

NASA Astrophysics Data System (ADS)

Abrahamse, H.; de Villiers, J.; Mvula, B.

2009-06-01

There are two fundamental types of stem cells: Embryonic Stem cells and Adult Stem cells. Adult Stem cells have a more restricted potential and can usually differentiate into a few different cell types. In the body these cells facilitate the replacement or repair of damaged or diseased cells in organs. Low intensity laser irradiation was shown to increase stem cell migration and stimulate proliferation and it is thought that treatment of these cells with laser irradiation may increase the stem cell harvest and have a positive effect on the viability and proliferation. Our research is aimed at determining the effect of laser irradiation on differentiation of Adipose Derived Stem Cells (ADSCs) into different cell types using a diode laser with a wavelength of 636 nm and at 5 J/cm2. Confirmation of stem cell characteristics and well as subsequent differentiation were assessed using Western blot analysis and cellular morphology supported by fluorescent live cell imaging. Functionality of subsequent differentiated cells was confirmed by measuring adenosine triphosphate (ATP) production and cell viability.

Alpha-fetoprotein, stem cells and cancer: how study of the production of alpha-fetoprotein during chemical hepatocarcinogenesis led to reaffirmation of the stem cell theory of cancer.

PubMed

Sell, Stewart

2008-01-01

Identification of the cells in the liver that produce alpha-fetoprotein during development, in response to liver injury and during the early stages of chemical hepatocarcinogenesis led to the conclusion that maturation arrest of liver-determined tissue stem cells was the cellular process that gives rise to hepatocellular carcinomas. When the cellular changes in these processes were compared to that of the formation of teratocarcinomas, the hypothesis arose that all cancers arise from maturation arrest of tissue-determined stem cells. This was essentially a reinterpretation of the embryonal rest theory of cancer whereby tissue stem cells take the role of embryonal rests. A corollary of the stem cell theory of the origin of cancer is that cancers contain the same functional cell populations as normal tissues: stem cells, transit-amplifying cells and mature cells. Cancer stem cells retain the essential feature of normal stem cells: the ability to self-renew. Growth of cancers is due to continued proliferation of cancer transit-amplifying cells that do not differentiate to mature cells (maturation arrest). On the other hand, cancer stem cells generally divide very rarely and contribute little to tumor growth. However, the presence of cancer stem cells in tumors is believed to be responsible for the properties of immortalization, transplantability and resistance to therapy characteristic of cancers. Current therapies for cancer (chemotherapy, radiotherapy, antiangiogenesis and differentiation therapy) are directed against the cancer transit-amplifying cells. When these therapies are discontinued, the cancer reforms from the cancer stem cells. Therapy directed toward interruption of the cell signaling pathways that maintain cancer stem cells could lead to new modalities to the prevention of regrowth of the cancer. Copyright 2008 S. Karger AG, Basel.

ALPHA-FETOPROTEIN (AFP), STEM CELLS, AND CANCER: HOW STUDY OF THE PRODUCTION OF AFP DURING CHEMICAL HEPATOCARCINOGENESIS LED TO REAFFIRMATION OF THE STEM CELL THEORY OF CANCER

PubMed Central

Sell, Stewart

2008-01-01

Identification of the cells in the liver that produce alpha-fetoprotein (AFP) during development, in response to liver injury, and during the early stages of chemical hepatocarcinogenesis led to the conclusion that maturation arrest of liver-determined tissue stem cells was the cellular process that gives rise to hepatocellular carcinomas (HCC). When the cellular changes in these processes were compared that of the formation of teratocarcinomas, the hypothesis arose that all cancers arise from maturation arrest of tissue determined stem cells. This was essentially a reinterpretation of the embryonal rest theory of cancer whereby tissue stem cells take the role of embryonal rests. A corollary of the stem cell theory of the origin of cancer is that cancers contain the same functional cell populations as do normal tissues: stem cells, transit-amplifying cells, and mature cells. Cancer stem cells retain the essential feature of normal stem cells: the ability to self-renew. Growth of cancers is due to continued proliferation of cancer transit-amplifying cells that do not differentiate to mature cells (maturation arrest). On the other hand, cancer stem cells generally divide very rarely and contribute little to tumor growth. However, the presence of cancer stem cells in tumors is believed to be responsible for the properties of immortalization, transplantability and resistance to therapy characteristic of cancers. Current therapies for cancer (chemotherapy, radiotherapy, anti-angiogenesis and differentiation therapy) are directed against the cancer transit amplifying cells. When these therapies are discontinued, the cancer re-forms from the cancer stem cells. Therapy directed toward interruption of the cell-signaling pathways that maintain cancer stem cells could lead to new modalities to the prevention of re-growth of the cancer. PMID:18612221

A Comparative Transcriptomic Analysis Reveals Conserved Features of Stem Cell Pluripotency in Planarians and Mammals

PubMed Central

Labbé, Roselyne M.; Irimia, Manuel; Currie, Ko W.; Lin, Alexander; Zhu, Shu Jun; Brown, David D.R.; Ross, Eric J.; Voisin, Veronique; Bader, Gary D.; Blencowe, Benjamin J.; Pearson, Bret J.

2014-01-01

Many long-lived species of animals require the function of adult stem cells throughout their lives. However, the transcriptomes of stem cells in invertebrates and vertebrates have not been compared, and consequently, ancestral regulatory circuits that control stem cell populations remain poorly defined. In this study, we have used data from high-throughput RNA sequencing to compare the transcriptomes of pluripotent adult stem cells from planarians with the transcriptomes of human and mouse pluripotent embryonic stem cells. From a stringently defined set of 4,432 orthologs shared between planarians, mice and humans, we identified 123 conserved genes that are ≥5-fold differentially expressed in stem cells from all three species. Guided by this gene set, we used RNAi screening in adult planarians to discover novel stem cell regulators, which we found to affect the stem cell-associated functions of tissue homeostasis, regeneration, and stem cell maintenance. Examples of genes that disrupted these processes included the orthologs of TBL3, PSD12, TTC27, and RACK1. From these analyses, we concluded that by comparing stem cell transcriptomes from diverse species, it is possible to uncover conserved factors that function in stem cell biology. These results provide insights into which genes comprised the ancestral circuitry underlying the control of stem cell self-renewal and pluripotency. PMID:22696458

Study of DNA extraction methods for use in loop-mediated isothermal amplification detection of single resting cysts in the toxic dinoflagellates Alexandrium tamarense and A. catenella.

PubMed

Nagai, Satoshi; Yamamoto, Keigo; Hata, Naotugu; Itakura, Shigeru

2012-09-01

In a previous study, we experienced instable amplification and a low amplification success in loop-mediated isothermal amplification (LAMP) reactions from naturally occurring vegetative cells or resting cysts of the toxic dinoflagellates Alexandrium tamarense and Alexandrium catenella. In this study, we examined 4 methods for extracting DNA from single resting cysts of A. tamarense and A. catenella to obtain more stable and better amplification success and to facilitate unambiguous detection using the LAMP method. Apart from comparing the 4 different DNA extraction methods, namely, (1) boiling in Tris-EDTA (TE) buffer, (2) heating at 65 °C in hexadecyltrimethylammonium bromide buffer, (3) boiling in 0.5% Chelex buffer, and (4) boiling in 5% Chelex buffer, we also examined the need for homogenization to crush the resting cysts before DNA extraction in each method. Homogenization of resting cysts was found to be essential for DNA extraction in all 4 methods. The detection time was significantly shorter in 5% Chelex buffer than in the other buffers and the amplification success was 100% (65/65), indicating the importance of DNA extraction and the effectiveness of 5% Chelex buffer in the Alexandrium LAMP. Copyright © 2012 Elsevier B.V. All rights reserved.

Arabidopsis HIPP27 is a host susceptibility gene for the beet cyst nematode Heterodera schachtii.

PubMed

Radakovic, Zoran S; Anjam, Muhammad Shahzad; Escobar, Elizabeth; Chopra, Divykriti; Cabrera, Javier; Silva, Ana Cláudia; Escobar, Carolina; Sobczak, Miroslaw; Grundler, Florian M W; Siddique, Shahid

2018-02-22

Sedentary plant-parasitic cyst nematodes are obligate biotrophs that infect the roots of their host plant. Their parasitism is based on the modification of root cells to form a hypermetabolic syncytium from which the nematodes draw their nutrients. The aim of this study was to identify nematode susceptibility genes in Arabidopsis thaliana and to characterize their roles in supporting the parasitism of Heterodera schachtii. By selecting genes that were most strongly upregulated in response to cyst nematode infection, we identified HIPP27 (HEAVY METAL-ASSOCIATED ISOPRENYLATED PLANT PROTEIN 27) as a host susceptibility factor required for beet cyst nematode infection and development. Detailed expression analysis revealed that HIPP27 is a cytoplasmic protein and that HIPP27 is strongly expressed in leaves, young roots and nematode-induced syncytia. Loss-of-function Arabidopsis hipp27 mutants exhibited severely reduced susceptibility to H. schachtii and abnormal starch accumulation in syncytial and peridermal plastids. Our results suggest that HIPP27 is a susceptibility gene in Arabidopsis whose loss of function reduces plant susceptibility to cyst nematode infection without increasing the susceptibility to other pathogens or negatively affecting the plant phenotype. © 2018 UNIVERSITY BONN. MOLECULAR PLANT PATHOLOGY © 2018 BSPP AND JOHN WILEY & SONS LTD.