Age and the means of bypassing stasis influence the intrinsic subtype of immortalized human mammary epithelial cells.

PubMed

Lee, Jonathan K; Garbe, James C; Vrba, Lukas; Miyano, Masaru; Futscher, Bernard W; Stampfer, Martha R; LaBarge, Mark A

2015-01-01

Based on molecular features, breast cancers are grouped into intrinsic subtypes that have different prognoses and therapeutic response profiles. With increasing age, breast cancer incidence increases, with hormone receptor-positive and other luminal-like subtype tumors comprising a majority of cases. It is not known at what stage of tumor progression subtype specification occurs, nor how the process of aging affects the intrinsic subtype. We examined subtype markers in immortalized human mammary epithelial cell lines established following exposure of primary cultured cell strains to a two-step immortalization protocol that targets the two main barriers to immortality: stasis (stress-associated senescence) and replicative senescence. Cell lines derived from epithelial cells obtained from non-tumorous pre- and post-menopausal breast surgery tissues were compared. Additionally, comparisons were made between lines generated using two different genetic interventions to bypass stasis: transduction of either an shRNA that down-regulated p16(INK4A), or overexpressed constitutive active cyclin D1/CDK2. In all cases, the replicative senescence barrier was bypassed by transduction of c-Myc. Cells from all resulting immortal lines exhibited normal karyotypes. Immunofluorescence, flow cytometry, and gene expression analyses of lineage-specific markers were used to categorize the intrinsic subtypes of the immortalized lines. Bypassing stasis with p16 shRNA in young strains generated cell lines that were invariably basal-like, but the lines examined from older strains exhibited some luminal features such as keratin 19 and estrogen receptor expression. Overexpression of cyclin D1/CDK2 resulted in keratin 19 positive, luminal-like cell lines from both young and old strains, and the lines examined from older strains exhibited estrogen receptor expression. Thus age and the method of bypassing stasis independently influence the subtype of immortalized human mammary epithelial cells.

Cutaneous perivascular epithelioid cell tumors: A review on an infrequent neoplasm

PubMed Central

Llamas-Velasco, Mar; Requena, Luis; Mentzel, Thomas

2016-01-01

“Perivascular epithelioid cutaneous” cell tumors (PEComa) are a family of mesenchymal tumors with shared microscopic and immunohistochemical properties: They exhibit both smooth muscle cell and melanocytic differentiation. Non-neoplastic counterpart of PEComa’s cells are unknown, as well as the relationship between extracutaneous PEComa and primary cutaneous ones. We will review the clinical setting, histopathologic features, chromosomal abnormalities, differential diagnosis and treatment options for cutaneous PEComa. PMID:27019799

Morphological Analysis of Live Undifferentiated Cells Derived from Induced Pluripotent Stem Cells.

PubMed

Osawa, Yukihiko; Miyamoto, Tomoyuki; Ohno, Setsuyo; Ohno, Eiji

2018-01-01

Induced pluripotent stem (iPS) cells possess pluripotency and self-renewal ability. Therefore, iPS cells are expected to be useful in regenerative medicine. However, iPS cells form malignant immature teratomas after transplantation into animals, even after differentiation induction. It has been suggested that undifferentiated cells expressing Nanog that remain after differentiation induction are responsible for teratoma formation. Various methods of removing these undifferentiated cells have therefore been investigated, but few methods involve morphological approaches, which may induce less cell damage. In addition, for cells derived from iPS cells to be applied in regenerative medicine, they must be alive. However, detailed morphological analysis of live undifferentiated cells has not been performed. For the above reasons, we assessed the morphological features of live undifferentiated cells remaining after differentiation induction as a basic investigation into the clinical application of iPS cells. As a result, live undifferentiated cells remaining after differentiation induction exhibited a round or oval cytoplasm about 12 μm in diameter and a nucleus. They exhibited nucleo-cytoplasmic (N/C) ratio of about 60% and eccentric nuclei, and they possessed partially granule-like structures in the cytoplasm and prominent nucleoli. Although they were similar to iPS cells, they were smaller than live iPS cells. Furthermore, very small cells were present among undifferentiated cells after differentiation induction. These results suggest that the removal of undifferentiated cells may be possible using the morphological features of live iPS cells and undifferentiated cells after differentiation induction. In addition, this study supports safe regenerative medicine using iPS cells.

Anti-Cancer Phytometabolites Targeting Cancer Stem Cells

PubMed Central

Torquato, Heron F.V.; Goettert, Márcia I.; Justo, Giselle Z.; Paredes-Gamero, Edgar J.

2017-01-01

Medicinal plants are a plentiful source of bioactive molecules with much structural diversity. In cancer treatment, molecules obtained from plants represent an attractive alternative to other treatments because several plant-derived compounds have exhibited lower toxicity and higher selectivity against cancer cells. In this review, we focus on the possible application of bioactive molecules obtained from plants against more primitive cell populations in cancers, cancer stem cells. Cancer stem cells are present in several kinds of tumors and are responsible for recurrences and metastases. Common anti-cancer drugs exhibit lower effectiveness against cancer stem cells because of their biological features. However, recently discovered natural phytometabolites exert cytotoxic effects on this rare population of cells in cancers. Therefore, this review presents the latest research on promising compounds from plants that can act as antitumor drugs and that mainly affect stem cell populations in cancers. PMID:28367074

Mapping the cellular and molecular heterogeneity of normal and malignant breast tissues and cultured cell lines

PubMed Central

2010-01-01

Introduction Normal and neoplastic breast tissues are comprised of heterogeneous populations of epithelial cells exhibiting various degrees of maturation and differentiation. While cultured cell lines have been derived from both normal and malignant tissues, it remains unclear to what extent they retain similar levels of differentiation and heterogeneity as that found within breast tissues. Methods We used 12 reduction mammoplasty tissues, 15 primary breast cancer tissues, and 20 human breast epithelial cell lines (16 cancer lines, 4 normal lines) to perform flow cytometry for CD44, CD24, epithelial cell adhesion molecule (EpCAM), and CD49f expression, as well as immunohistochemistry, and in vivo tumor xenograft formation studies to extensively analyze the molecular and cellular characteristics of breast epithelial cell lineages. Results Human breast tissues contain four distinguishable epithelial differentiation states (two luminal phenotypes and two basal phenotypes) that differ on the basis of CD24, EpCAM and CD49f expression. Primary human breast cancer tissues also contain these four cellular states, but in altered proportions compared to normal tissues. In contrast, cultured cancer cell lines are enriched for rare basal and mesenchymal epithelial phenotypes, which are normally present in small numbers within human tissues. Similarly, cultured normal human mammary epithelial cell lines are enriched for rare basal and mesenchymal phenotypes that represent a minor fraction of cells within reduction mammoplasty tissues. Furthermore, although normal human mammary epithelial cell lines exhibit features of bi-potent progenitor cells they are unable to differentiate into mature luminal breast epithelial cells under standard culture conditions. Conclusions As a group breast cancer cell lines represent the heterogeneity of human breast tumors, but individually they exhibit increased lineage-restricted profiles that fall short of truly representing the intratumoral heterogeneity of individual breast tumors. Additionally, normal human mammary epithelial cell lines fail to retain much of the cellular diversity found in human breast tissues and are enriched for differentiation states that are a minority in breast tissues, although they do exhibit features of bi-potent basal progenitor cells. These findings suggest that collections of cell lines representing multiple cell types can be used to model the cellular heterogeneity of tissues. PMID:20964822

P53 nuclear stabilization is associated with FHIT loss and younger age of onset in squamous cell carcinoma of oral tongue

PubMed Central

2014-01-01

Background Squamous cell carcinoma of tongue (SCCT) is expected to harbor unique clinico-pathological and molecular genetic features since a significant proportion of patients are young and exhibit no association with tobacco or alcohol. Methods We determined P53, epidermal growth factor receptor, microsatellite instability, human papilloma virus infection and loss of heterozygosity status at several tumor suppressor loci in one hundred and twenty one oral SCCT (SSCOT) samples and analyzed their association with clinico-pathological features and patient survival. Results Our results revealed a significantly higher incidence of p53 nuclear stabilization in early (as against late) onset SCCOT. FHIT loss was significantly associated with p53 nuclear stabilization and the association was stronger in patients with no history of tobacco use. Samples harboring mutation in p53 DNA binding domain or exhibiting p53 nuclear stabilization, were significantly associated with poor survival. Conclusion Our study has therefore identified distinct features in SCCOT tumorigenesis with respect to age and tobacco exposure and revealed possible prognostic utility of p53. PMID:25152695

Cytological and ultrastructural studies on root tissues

NASA Technical Reports Server (NTRS)

Slocum, R. D.; Gaynor, J. J.; Galston, A. W.

1984-01-01

The anatomy and fine structure of roots from oat and mung bean seedlings, grown under microgravity conditions for 8 days aboard the Space Shuttle, was examined and compared to that of roots from ground control plants grown under similar conditions. Roots from both sets of oat seedlings exhibited characteristic monocotyledonous tissue organization and normal ultrastructural features, except for cortex cell mitochondria, which exhibited a 'swollen' morphology. Various stages of cell division were observed in the meristematic tissues of oat roots. Ground control and flight-grown mung bean roots also showed normal tissue organization, but root cap cells in the flight-grown roots were collapsed and degraded in appearance, especially at the cap periphery. At the ultrastructural level, these cells exhibited a loss of organelle integrity and a highly-condensed cytoplasm. This latter observation perhaps suggests a differing tissue sensitivity for the two species to growth conditions employed in space flight. The basis for abnormal root cap cell development is not understood, but the loss of these putative gravity-sensing cells holds potential significance for long term plant growth orientation during space flight.

Immunohistochemical mismatch in a case of rhabdomyoblastic metastatic melanoma.

PubMed

Dumitru, Adrian Vasile; Tampa, Mircea Ştefan; Georgescu, Simona Roxana; Păunică, Stana; Matei, Clara Nicoleta; Nica, Adriana Elena; Costache, Mariana; Motofei, Ion; Sajin, Maria; Păunică, Ioana; Georgescu, Tiberiu Augustin

2018-01-01

Melanomas can exhibit a wide range of unusual morphologies due to the neural crest origin of melanocytes. Several authors have documented variations in size and shape of cells, cytoplasmic features and inclusions, nuclear features and cell architecture. Metastatic melanoma with rhabdomyoblastic differentiation is an extremely rare condition with poor prognosis. Few studies concerning rhabdoid or rhabdomyoblastic differentiation in melanoma are currently available and the current report highlights some of the most important immunohistochemical features of this rare entity. We report on a case of a rhabdomyoblastic metastatic melanoma showing intense positivity for both melanocytic and rhabdoid markers in two cell populations dissociated within the tumor with multiple mismatches in immunomarker expression. Improved recognition of this rare morphological pattern may provide the means for developing new techniques to identify novel therapeutic targets, which would improve the prognostic outlook for these patients.

Intracranial glioblastoma models in preclinical neuro-oncology: neuropathological characterization and tumor progression

PubMed Central

Candolfi, Marianela; Curtin, James F.; Stephen Nichols, W.; Muhammad, AKM. G.; King, Gwendalyn D.; Elizabeth Pluhar, G.; McNiel, Elizabeth A.; Ohlfest, John R.; Freese, Andrew B.; Moore, Peter F.; Lerner, Jonathan; Lowenstein, Pedro R.

2008-01-01

Although rodent glioblastoma (GBM) models have been used for over 30 years, the extent to which they recapitulate the characteristics encountered in human GBMs remains controversial. We studied the histopathological features of dog GBM and human xenograft GBM models in immune-deficient mice (U251 and U87 GBM in nude Balb/c), and syngeneic GBMs in immune-competent rodents (GL26 cells in C57BL/6 mice, CNS-1 cells in Lewis rats). All GBMs studied exhibited neovascularization, pleomorphism, vimentin immunoreactivity, and infiltration of T-cells and macrophages. All the tumors showed necrosis and hemorrhages, except the U87 human xenograft, in which the most salient feature was its profuse neovascularization. The tumors differed in the expression of astrocytic intermediate filaments: human and dog GBMs, as well as U251 xenografts expressed glial fibrillary acidic protein (GFAP) and vimentin, while the U87 xenograft and the syngeneic rodent GBMs were GFAP− and vimentin+. Also, only dog GBMs exhibited endothelial proliferation, a key feature that was absent in the murine models. In all spontaneous and implanted GBMs we found histopathological features compatible with tumor invasion into the non-neoplastic brain parenchyma. Our data indicate that murine models of GBM appear to recapitulate several of the human GBM histopathological features and, considering their reproducibility and availability, they constitute a valuable in vivo system for preclinical studies. Importantly, our results indicate that dog GBM emerges as an attractive animal model for testing novel therapies in a spontaneous tumor in the context of a larger brain. PMID:17874037

The Global Regulatory Architecture of Transcription during the Caulobacter Cell Cycle

PubMed Central

Zhou, Bo; Schrader, Jared M.; Kalogeraki, Virginia S.; Abeliuk, Eduardo; Dinh, Cong B.; Pham, James Q.; Cui, Zhongying Z.; Dill, David L.; McAdams, Harley H.; Shapiro, Lucy

2015-01-01

Each Caulobacter cell cycle involves differentiation and an asymmetric cell division driven by a cyclical regulatory circuit comprised of four transcription factors (TFs) and a DNA methyltransferase. Using a modified global 5′ RACE protocol, we globally mapped transcription start sites (TSSs) at base-pair resolution, measured their transcription levels at multiple times in the cell cycle, and identified their transcription factor binding sites. Out of 2726 TSSs, 586 were shown to be cell cycle-regulated and we identified 529 binding sites for the cell cycle master regulators. Twenty-three percent of the cell cycle-regulated promoters were found to be under the combinatorial control of two or more of the global regulators. Previously unknown features of the core cell cycle circuit were identified, including 107 antisense TSSs which exhibit cell cycle-control, and 241 genes with multiple TSSs whose transcription levels often exhibited different cell cycle timing. Cumulatively, this study uncovered novel new layers of transcriptional regulation mediating the bacterial cell cycle. PMID:25569173

The global regulatory architecture of transcription during the Caulobacter cell cycle.

PubMed

Zhou, Bo; Schrader, Jared M; Kalogeraki, Virginia S; Abeliuk, Eduardo; Dinh, Cong B; Pham, James Q; Cui, Zhongying Z; Dill, David L; McAdams, Harley H; Shapiro, Lucy

2015-01-01

Each Caulobacter cell cycle involves differentiation and an asymmetric cell division driven by a cyclical regulatory circuit comprised of four transcription factors (TFs) and a DNA methyltransferase. Using a modified global 5' RACE protocol, we globally mapped transcription start sites (TSSs) at base-pair resolution, measured their transcription levels at multiple times in the cell cycle, and identified their transcription factor binding sites. Out of 2726 TSSs, 586 were shown to be cell cycle-regulated and we identified 529 binding sites for the cell cycle master regulators. Twenty-three percent of the cell cycle-regulated promoters were found to be under the combinatorial control of two or more of the global regulators. Previously unknown features of the core cell cycle circuit were identified, including 107 antisense TSSs which exhibit cell cycle-control, and 241 genes with multiple TSSs whose transcription levels often exhibited different cell cycle timing. Cumulatively, this study uncovered novel new layers of transcriptional regulation mediating the bacterial cell cycle.

Choreography of the Mycobacterium Replication Machinery during the Cell Cycle

PubMed Central

Trojanowski, Damian; Ginda, Katarzyna; Pióro, Monika; Hołówka, Joanna; Skut, Partycja; Jakimowicz, Dagmara

2015-01-01

ABSTRACT It has recently been demonstrated that bacterial chromosomes are highly organized, with specific positioning of the replication initiation region. Moreover, the positioning of the replication machinery (replisome) has been shown to be variable and dependent on species-specific cell cycle features. Here, we analyzed replisome positions in Mycobacterium smegmatis, a slow-growing bacterium that exhibits characteristic asymmetric polar cell extension. Time-lapse fluorescence microscopy analyses revealed that the replisome is slightly off-center in mycobacterial cells, a feature that is likely correlated with the asymmetric growth of Mycobacterium cell poles. Estimates of the timing of chromosome replication in relation to the cell cycle, as well as cell division and chromosome segregation events, revealed that chromosomal origin-of-replication (oriC) regions segregate soon after the start of replication. Moreover, our data demonstrate that organization of the chromosome by ParB determines the replisome choreography. PMID:25691599

Cutaneous angiosarcoma mimicking xanthoma: a challenging histopathologic diagnosis with important consequences.

PubMed

Llamas-Velasco, Mar; Kutzner, Heinz; Requena, Luis

2016-09-01

Cutaneous angiosarcoma may show protean histopathologic features. Rare or uncommon variants include epithelioid, clear cell, granular cell, verrucous, pseudolymphomatous and signet-ring cell types. Perhaps the rarest type consists of cutaneous angiosarcoma with xanthomization of neoplastic cells. We report an extraordinary case with almost all neoplastic cells exhibiting a xanthomatous appearance that was studied both histopathologically and immunohistochemically. We discuss the histopathologic differential diagnosis of foamy cell angiosarcoma with other neoplasms that may show similar histopathology. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mitochondrial pyruvate carrier function is negatively linked to Warburg phenotype in vitro and malignant features in esophageal squamous cell carcinomas

PubMed Central

Li, Yaqing; Li, Xiaoran; Kan, Quancheng; Zhang, Mingzhi; Li, Xiaoli; Xu, Ruiping; Wang, Junsheng; Yu, Dandan; Goscinski, Mariusz Adam; Wen, Jian-Guo; Nesland, Jahn M.; Suo, Zhenhe

2017-01-01

Aerobic glycolysis is one of the emerging hallmarks of cancer cells. In this study, we investigated the relationship between blocking mitochondrial pyruvate carrier (MPC) with MPC blocker UK5099 and the metabolic alteration as well as aggressive features of esophageal squamous carcinoma. It was found that blocking pyruvate transportation into mitochondria attenuated mitochondrial oxidative phosphorylation (OXPHOS) and triggered aerobic glycolysis, a feature of Warburg effect. In addition, the HIF-1α expression and ROS production were also activated upon UK5099 application. It was further revealed that the UK5099-treated cells became significantly more resistant to chemotherapy and radiotherapy, and the UK5099-treated tumor cells also exhibited stronger invasive capacity compared to the parental cells. In contrast to esophageal squamous epithelium cells, decreased MPC protein expression was observed in a series of 157 human squamous cell carcinomas, and low/negative MPC1 expression predicted an unfavorable clinical outcome. All these results together revealed the potential connection of altered MPC expression/activity with the Warburg metabolic reprogramming and tumor aggressiveness in cell lines and clinical samples. Collectively, our findings highlighted a therapeutic strategy targeting Warburg reprogramming of human esophageal squamous cell carcinomas. PMID:27911865

Synovial mesenchymal stem cells from osteo- or rheumatoid arthritis joints exhibit good potential for cartilage repair using a scaffold-free tissue engineering approach.

PubMed

Koizumi, K; Ebina, K; Hart, D A; Hirao, M; Noguchi, T; Sugita, N; Yasui, Y; Chijimatsu, R; Yoshikawa, H; Nakamura, N

2016-08-01

To assess whether synovial mesenchymal stem cells (SMSCs) from patients with osteoarthritis (OA) or rheumatoid arthritis (RA) can be used as an alternative cell source for cartilage repair using allogenic tissue engineered construct (TEC). Twenty-five patients (17 female, average age 61.8 years) were divided according to their pathology (control trauma group; N = 6, OA group; N = 6) and RA patients were subdivided into two groups to evaluate the impact of biologics in accordance with whether treated with biologics [Bio(+)RA; N = 7] or not [Bio(-)RA; N = 6]. We compared the following characteristics among these groups: (1) The cell proliferation capacity of SMSCs; (2) The influence of passage number on features of SMSCs; (3) The weight and volume of TEC from the same number of SMSCs; (4) Inflammatory cytokine gene expressions levels of TEC; (5) The chondrogenic potential of TEC; and (6) Osteochondral repair using TEC in athymic nude rats. SMSCs from the four groups exhibited equivalent features in the above evaluation items. In in vivo studies, the TEC-treated repair tissues for all groups exhibited significantly better outcomes than those for the untreated group and no significant differences among the four TEC groups. SMSCs from OA or RA patients are no less appropriate for repairing cartilage than those from trauma patients and thus, may be an effective source for allogenic cell-based cartilage repair. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Comparisons of Supergranule Properties from SDO/HMI with Other Datasets

NASA Technical Reports Server (NTRS)

Pesnell, William Dean; Williams, Peter E.

2010-01-01

While supergranules, a component of solar convection, have been well studied through the use of Dopplergrams, other datasets also exhibit these features. Quiet Sun magnetograms show local magnetic field elements distributed around the boundaries of supergranule cells, notably clustering at the common apex points of adjacent cells, while more solid cellular features are seen near active regions. Ca II K images are notable for exhibiting the chromospheric network representing a cellular distribution of local magnetic field lines across the solar disk that coincides with supergranulation boundaries. Measurements at 304 A further above the solar surface also show a similar pattern to the chromospheric network, but the boundaries are more nebulous in nature. While previous observations of these different solar features were obtained with a variety of instruments, SDO provides a single platform, from which the relevant data products at a high cadence and high-definition image quality are delivered. The images may also be cross-referenced due to their coincidental time of observation. We present images of these different solar features from HMI & AIA and use them to make composite images of supergranules at different atmospheric layers in which they manifest. We also compare each data product to equivalent data from previous observations, for example HMI magnetograms with those from MDI.

Detection of abnormal extracellular matrix in the interstitium of regenerating renal tubules.

PubMed

Minuth, Will W; Denk, Lucia

2014-12-15

Stem/progenitor cells are promising candidates for the regeneration of parenchyma in acute and chronic renal failure. However, recent data exhibit that survival of stem/progenitor cells after implantation in diseased renal parenchyma is restricted. To elaborate basic parameters improving survival, cell seeding was simulated under advanced in vitro conditions. After isolation, renal stem/progenitor cells were mounted in a polyester interstitium for perfusion culture. During generation of tubules, chemically defined CO2 Independent Medium or Leibovitz's L-15 Medium was applied. Specimens were then fixed for transmission electron microscopy to analyze morphological features in generated tubules. Fixation in conventional glutaraldehyde (GA) solution shows development of tubules each exhibiting a polarized epithelium, an intact basal lamina and an inconspicuous interstitium. In contrast, special fixation of specimens in GA solution containing cupromeronic blue, ruthenium red or tannic acid unveils previously not visible extracellular matrix. Control experiments elucidate that a comparable extracellular matrix is not present in the interstitium of the matured kidney. Thus, generation of renal tubules in combination with advanced fixation of specimens for electron microscopy demonstrates that development of abnormal features in the newly developed interstitium has to be considered, when repair of renal parenchyma is performed by implantation of stem/progenitor cells.

Chromosomal instability: A common feature and a therapeutic target of cancer.

PubMed

Tanaka, Kozo; Hirota, Toru

2016-08-01

Most cancer cells are aneuploid, containing abnormal numbers of chromosomes, mainly caused by elevated levels of chromosome missegregation, known as chromosomal instability (CIN). These well-recognized, but poorly understood, features of cancers have recently been studied extensively, unraveling causal relationships between CIN and cancer. Here we review recent findings regarding how CIN and aneuploidy occur, how they affect cellular functions, how cells respond to them, and their relevance to diseases, especially cancer. Aneuploid cells are under various kinds of stresses that result in reduced cellular fitness. Nevertheless, genetic heterogeneity derived from CIN allows the selection of cells better adapted to their environment, which supposedly facilitates generation and progression of cancer. We also discuss how we can exploit the properties of cancer cells exhibiting CIN for effective cancer therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Aspects of vertebrate gustatory phylogeny: morphology and turnover of chick taste bud cells.

PubMed

Ganchrow, J R; Ganchrow, D; Royer, S M; Kinnamon, J C

1993-10-01

The taste bud is a receptor form observed across vertebrates. The present report compares chick taste buds to those of other vertebrates using light and electron microscopy. Unlike mammals, but common to many modern avians, the dorsal surface of chick anterior tongue lacks taste papillae and taste buds. Ultrastructurally, chick buds located in the anterior floor of the mouth (as in some reptiles and amphibians) and palate contain dark, intermediate, light, and basal cell types. Dark, intermediate, and light cells extend microvilli into intragemmal lumina and pores communicating with the oral cavity. As specialized features, dark cell apices lack dense granules and exhibit short microvilli relative to light and intermediate cells. Dark cell cytoplasmic fingers envelop intragemmal nerve fibers and cells as in other species, and sometimes contain abundant clear vesicles. Nerve profile expansions often are located adjacent to dark, intermediate, and light cell nuclei. Classical afferent synaptic contacts are rarely observed. Taste cell turnover is suggested by mitotic and degenerating figures in chick buds. In addition, tritiated thymidine injected into hatchlings, whose anterior mandibular oral taste bud population approximates that in adults, reveals a turnover rate of about 4.5 days. This is about half that observed in altricial mammals, reflecting a species difference or developmental factor in precocial avians. It is concluded that chick taste buds exhibit morphologic features common to other vertebrate buds with specializations reflecting the influences of niche, glandular relations, and/or age.

Lineage analysis of micromere 4d, a super-phylotypic cell for Lophotrochozoa, in the leech Helobdella and the sludgeworm Tubifex.

PubMed

Gline, Stephanie E; Nakamoto, Ayaki; Cho, Sung-Jin; Chi, Candace; Weisblat, David A

2011-05-01

The super-phylum Lophotrochozoa contains the plurality of extant animal phyla and exhibits a corresponding diversity of adult body plans. Moreover, in contrast to Ecdysozoa and Deuterostomia, most lophotrochozoans exhibit a conserved pattern of stereotyped early divisions called spiral cleavage. In particular, bilateral mesoderm in most lophotrochozoan species arises from the progeny of micromere 4d, which is assumed to be homologous with a similar cell in the embryo of the ancestral lophotrochozoan, more than 650 million years ago. Thus, distinguishing the conserved and diversified features of cell fates in the 4d lineage among modern spiralians is required to understand how lophotrochozoan diversity has evolved by changes in developmental processes. Here we analyze cell fates for the early progeny of the bilateral daughters (M teloblasts) of micromere 4d in the leech Helobdella sp. Austin, a clitellate annelid. We show that the first six progeny of the M teloblasts (em1-em6) contribute five different sets of progeny to non-segmental mesoderm, mainly in the head and in the lining of the digestive tract. The latter feature, associated with cells em1 and em2 in Helobdella, is seen with the M teloblast lineage in a second clitellate species, the sludgeworm Tubifex tubifex and, on the basis of previously published work, in the initial progeny of the M teloblast homologs in molluscan species, suggesting that it may be an ancestral feature of lophotrochozoan development. Copyright © 2011 Elsevier Inc. All rights reserved.

Adenoid cystic carcinoma of breast: Recent advances

PubMed Central

Miyai, Kosuke; Schwartz, Mary R; Divatia, Mukul K; Anton, Rose C; Park, Yong Wook; Ayala, Alberto G; Ro, Jae Y

2014-01-01

Adenoid cystic carcinoma (ACC) of the breast is a rare special subtype of breast cancer characterized by the presence of a dual cell population of luminal and basaloid cells arranged in specific growth patterns. Most breast cancers with triple-negative, basal-like breast features (i.e., tumors that are devoid of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression, and express basal cell markers) are generally high-grade tumors with an aggressive clinical course. Conversely, while ACCs also display a triple-negative, basal-like phenotype, they are usually low-grade and exhibit an indolent clinical behavior. Many discoveries regarding the molecular and genetic features of the ACC, including a specific chromosomal translocation t(6;9) that results in a MYB-NFIB fusion gene, have been made in recent years. This comprehensive review provides our experience with the ACC of the breast, as well as an overview of clinical, histopathological, and molecular genetic features. PMID:25516849

Single molecule and single cell epigenomics.

PubMed

Hyun, Byung-Ryool; McElwee, John L; Soloway, Paul D

2015-01-15

Dynamically regulated changes in chromatin states are vital for normal development and can produce disease when they go awry. Accordingly, much effort has been devoted to characterizing these states under normal and pathological conditions. Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is the most widely used method to characterize where in the genome transcription factors, modified histones, modified nucleotides and chromatin binding proteins are found; bisulfite sequencing (BS-seq) and its variants are commonly used to characterize the locations of DNA modifications. Though very powerful, these methods are not without limitations. Notably, they are best at characterizing one chromatin feature at a time, yet chromatin features arise and function in combination. Investigators commonly superimpose separate ChIP-seq or BS-seq datasets, and then infer where chromatin features are found together. While these inferences might be correct, they can be misleading when the chromatin source has distinct cell types, or when a given cell type exhibits any cell to cell variation in chromatin state. These ambiguities can be eliminated by robust methods that directly characterize the existence and genomic locations of combinations of chromatin features in very small inputs of cells or ideally, single cells. Here we review single molecule epigenomic methods under development to overcome these limitations, the technical challenges associated with single molecule methods and their potential application to single cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Single Molecule and Single Cell Epigenomics

PubMed Central

Hyun, Byung-Ryool; McElwee, John L.; Soloway, Paul D.

2014-01-01

Dynamically regulated changes in chromatin states are vital for normal development and can produce disease when they go awry. Accordingly, much effort has been devoted to characterizing these states under normal and pathological conditions. Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is the most widely used method to characterize where in the genome transcription factors, modified histones, modified nucleotides and chromatin binding proteins are found; bisulfite sequencing (BS-seq) and its variants are commonly used to characterize the locations of DNA modifications. Though very powerful, these methods are not without limitations. Notably, they are best at characterizing one chromatin feature at a time, yet chromatin features arise and function in combination. Investigators commonly superimpose separate ChIP-seq or BS-seq datasets, and then infer where chromatin features are found together. While these inferences might be correct, they can be misleading when the chromatin source has distinct cell types, or when a given cell type exhibits any cell to cell variation in chromatin state. These ambiguities can be eliminated by robust methods that directly characterize the existence and genomic locations of combinations of chromatin features in very small inputs of cells or ideally, single cells. Here we review single molecule epigenomic methods under development to overcome these limitations, the technical challenges associated with single molecule methods and their potential application to single cells. PMID:25204781

Induced pluripotent stem cells derived from rabbits exhibit some characteristics of naïve pluripotency

PubMed Central

Osteil, Pierre; Tapponnier, Yann; Markossian, Suzy; Godet, Murielle; Schmaltz-Panneau, Barbara; Jouneau, Luc; Cabau, Cédric; Joly, Thierry; Blachère, Thierry; Gócza, Elen; Bernat, Agnieszka; Yerle, Martine; Acloque, Hervé; Hidot, Sullivan; Bosze, Zsuzsanna; Duranthon, Véronique; Savatier, Pierre; Afanassieff, Marielle

2013-01-01

Summary Not much is known about the molecular and functional features of pluripotent stem cells (PSCs) in rabbits. To address this, we derived and characterized 2 types of rabbit PSCs from the same breed of New Zealand White rabbits: 4 lines of embryonic stem cells (rbESCs), and 3 lines of induced PSCs (rbiPSCs) that were obtained by reprogramming adult skin fibroblasts. All cell lines required fibroblast growth factor 2 for their growth and proliferation. All rbESC lines showed molecular and functional properties typically associated with primed pluripotency. The cell cycle of rbESCs had a prolonged G1 phase and a DNA damage checkpoint before entry into the S phase, which are the 2 features typically associated with the somatic cell cycle. In contrast, the rbiPSC lines exhibited some characteristics of naïve pluripotency, including resistance to single-cell dissociation by trypsin, robust activity of the distal enhancer of the mouse Oct4 gene, and expression of naïve pluripotency-specific genes, as defined in rodents. According to gene expression profiles, rbiPSCs were closer to the rabbit inner cell mass (ICM) than rbESCs. Furthermore, rbiPSCs were capable of colonizing the ICM after aggregation with morulas. Therefore, we propose that rbiPSCs self-renew in an intermediate state between naïve and primed pluripotency, which represents a key step toward the generation of bona fide naïve PSC lines in rabbits. PMID:23789112

Stimulus encoding and feature extraction by multiple sensory neurons.

PubMed

Krahe, Rüdiger; Kreiman, Gabriel; Gabbiani, Fabrizio; Koch, Christof; Metzner, Walter

2002-03-15

Neighboring cells in topographical sensory maps may transmit similar information to the next higher level of processing. How information transmission by groups of nearby neurons compares with the performance of single cells is a very important question for understanding the functioning of the nervous system. To tackle this problem, we quantified stimulus-encoding and feature extraction performance by pairs of simultaneously recorded electrosensory pyramidal cells in the hindbrain of weakly electric fish. These cells constitute the output neurons of the first central nervous stage of electrosensory processing. Using random amplitude modulations (RAMs) of a mimic of the fish's own electric field within behaviorally relevant frequency bands, we found that pyramidal cells with overlapping receptive fields exhibit strong stimulus-induced correlations. To quantify the encoding of the RAM time course, we estimated the stimuli from simultaneously recorded spike trains and found significant improvements over single spike trains. The quality of stimulus reconstruction, however, was still inferior to the one measured for single primary sensory afferents. In an analysis of feature extraction, we found that spikes of pyramidal cell pairs coinciding within a time window of a few milliseconds performed significantly better at detecting upstrokes and downstrokes of the stimulus compared with isolated spikes and even spike bursts of single cells. Coincident spikes can thus be considered "distributed bursts." Our results suggest that stimulus encoding by primary sensory afferents is transformed into feature extraction at the next processing stage. There, stimulus-induced coincident activity can improve the extraction of behaviorally relevant features from the stimulus.

Effect of cell-size on the energy absorption features of closed-cell aluminium foams

NASA Astrophysics Data System (ADS)

Nammi, S. K.; Edwards, G.; Shirvani, H.

2016-11-01

The effect of cell-size on the compressive response and energy absorption features of closed-cell aluminium (Al) foam were investigated by finite element method. Micromechanical models were constructed with a repeating unit-cell (RUC) which was sectioned from tetrakaidecahedra structure. Using this RUC, three Al foam models with different cell-sizes (large, medium and small) and all of same density, were built. These three different cell-size pieces of foam occupy the same volume and their domains contained 8, 27 and 64 RUCs respectively. However, the smaller cell-size foam has larger surface area to volume ratio compared to other two. Mechanical behaviour was modelled under uniaxial loading. All three aggregates (3D arrays of RUCs) of different cell-sizes showed an elastic region at the initial stage, then followed by a plateau, and finally, a densification region. The smaller cell size foam exhibited a higher peak-stress and a greater densification strain comparing other two cell-sizes investigated. It was demonstrated that energy absorption capabilities of smaller cell-size foams was higher compared to the larger cell-sizes examined.

pH-responsive, gluconeogenic renal epithelial LLC-PK1-FBPase+cells: a versatile in vitro model to study renal proximal tubule metabolism and function

PubMed Central

Curthoys, Norman P.

2014-01-01

Ammoniagenesis and gluconeogenesis are prominent metabolic features of the renal proximal convoluted tubule that contribute to maintenance of systemic acid-base homeostasis. Molecular analysis of the mechanisms that mediate the coordinate regulation of the two pathways required development of a cell line that recapitulates these features in vitro. By adapting porcine renal epithelial LLC-PK1 cells to essentially glucose-free medium, a gluconeogenic subline, termed LLC-PK1-FBPase+ cells, was isolated. LLC-PK1-FBPase+ cells grow in the absence of hexoses and pentoses and exhibit enhanced oxidative metabolism and increased levels of phosphate-dependent glutaminase. The cells also express significant levels of the key gluconeogenic enzymes, fructose-1,6-bisphosphatase (FBPase) and phosphoenolpyruvate carboxykinase (PEPCK). Thus the altered phenotype of LLC-PK1-FBPase+ cells is pleiotropic. Most importantly, when transferred to medium that mimics a pronounced metabolic acidosis (9 mM HCO3−, pH 6.9), the LLC-PK1-FBPase+ cells exhibit a gradual increase in NH4+ ion production, accompanied by increases in glutaminase and cytosolic PEPCK mRNA levels and proteins. Therefore, the LLC-PK1-FBPase+ cells retained in culture many of the metabolic pathways and pH-responsive adaptations characteristic of renal proximal tubules. The molecular mechanisms that mediate enhanced expression of the glutaminase and PEPCK in LLC-PK1-FBPase+ cells have been extensively reviewed. The present review describes novel properties of this unique cell line and summarizes the molecular mechanisms that have been defined more recently using LLC-PK1-FBPase+ cells to model the renal proximal tubule. It also identifies future studies that could be performed using these cells. PMID:24808535

Two-Photon Microscopy Imaging of thy1GFP-M Transgenic Mice: A Novel Animal Model to Investigate Brain Dendritic Cell Subsets In Vivo

PubMed Central

Laperchia, Claudia; Allegra Mascaro, Anna L.; Sacconi, Leonardo; Andrioli, Anna; Mattè, Alessandro; De Franceschi, Lucia; Grassi-Zucconi, Gigliola; Bentivoglio, Marina; Buffelli, Mario; Pavone, Francesco S.

2013-01-01

Transgenic mice expressing fluorescent proteins in specific cell populations are widely used for in vivo brain studies with two-photon fluorescence (TPF) microscopy. Mice of the thy1GFP-M line have been engineered for selective expression of green fluorescent protein (GFP) in neuronal populations. Here, we report that TPF microscopy reveals, at the brain surface of these mice, also motile non-neuronal GFP+ cells. We have analyzed the behavior of these cells in vivo and characterized in brain sections their immunophenotype. With TPF imaging, motile GFP+ cells were found in the meninges, subarachnoid space and upper cortical layers. The striking feature of these cells was their ability to move across the brain parenchyma, exhibiting evident shape changes during their scanning-like motion. In brain sections, GFP+ cells were immunonegative to antigens recognizing motile cells such as migratory neuroblasts, neuronal and glial precursors, mast cells, and fibroblasts. GFP+ non-neuronal cells exhibited instead the characteristic features and immunophenotype (CD11c and major histocompatibility complex molecule class II immunopositivity) of dendritic cells (DCs), and were immunonegative to the microglial marker Iba-1. GFP+ cells were also identified in lymph nodes and blood of thy1GFP-M mice, supporting their identity as DCs. Thus, TPF microscopy has here allowed the visualization for the first time of the motile behavior of brain DCs in situ. The results indicate that the thy1GFP-M mouse line provides a novel animal model for the study of subsets of these professional antigen-presenting cells in the brain. Information on brain DCs is still very limited and imaging in thy1GFP-M mice has a great potential for analyses of DC-neuron interaction in normal and pathological conditions. PMID:23409142

The Paramyxea Levine 1979: An original example of evolution towards multicellularity

NASA Astrophysics Data System (ADS)

Desportes, Isabelle

1984-03-01

The Paramyxea are parasitic in marine invertebrates. Their development is a sporulation involving the differentiation within a stem cell of several sporonts which produce spores made of cells enclosed inside each other. Three genera are recognized according to the number of spores and sporal cells, and the taxonomic position of the host (Polychaeta, Mollusca, Crustacea). The Paramyxea exhibit both protistan and metazoan characters. Their nine singlets centrioles are observed in different Protoctists whereas the fact that their sporal cells acquire distinctive cytological features may be interpreted as an evolution towards multicellularity.

Influence of non-adherent yeast cells on electrical characteristics of diamond-based field-effect transistors

NASA Astrophysics Data System (ADS)

Procházka, Václav; Cifra, Michal; Kulha, Pavel; Ižák, Tibor; Rezek, Bohuslav; Kromka, Alexander

2017-02-01

Diamond thin films provide unique features as substrates for cell cultures and as bio-electronic sensors. Here we employ solution-gated field effect transistors (SGFET) based on nanocrystalline diamond thin films with H-terminated surface which exhibits the sub-surface p-type conductive channel. We study an influence of yeast cells (Saccharomyces cerevisiae) on electrical characteristics of the diamond SGFETs. Two different cell culture solutions (sucrose and yeast peptone dextrose-YPD) are used, with and without the cells. We have found that transfer characteristics of the SGFETs exhibit a negative shift of the gate voltage by -26 mV and -42 mV for sucrose and YPD with cells in comparison to blank solutions without the cells. This effect is attributed to a local pH change in close vicinity of the H-terminated diamond surface due to metabolic processes of the yeast cells. The pH sensitivity of the diamond-based SGFETs, the role of cell and protein adhesion on the gate surface and the role of negative surface charge of yeast cells on the SGFETs electrical characteristics are discussed as well.

High performance polymer chemical hydrogel-based electrode binder materials for direct borohydride fuel cells

NASA Astrophysics Data System (ADS)

Choudhury, Nurul A.; Ma, Jia; Sahai, Yogeshwar; Buchheit, Rudolph G.

Novel, cost-effective, high-performance, and environment-friendly electrode binders, comprising polyvinyl alcohol chemical hydrogel (PCH) and chitosan chemical hydrogel (CCH), are reported for direct borohydride fuel cells (DBFCs). PCH and CCH binders-based electrodes have been fabricated using a novel, simple, cost-effective, time-effective, and environmentally benign technique. Morphologies and electrochemical performance in DBFCs of the chemical hydrogel binder-based electrodes have been compared with those of Nafion ® binder-based electrodes. Relationships between the performance of binders in DBFCs with structural features of the polymers and the polymer-based chemical hydrogels are discussed. The CCH binder exhibited better performance than a Nafion ® binder whereas the PCH binder exhibited comparable performance to Nafion ® in DBFCs operating at elevated cell temperatures. The better performance of CCH binder at higher operating cell temperatures has been ascribed to the hydrophilic nature and water retention characteristics of chitosan. DBFCs employing CCH binder-based electrodes and a Nafion ®-117 membrane as an electrolyte exhibited a maximum peak power density of about 589 mW cm -2 at 70 °C.

Loss of Hfe Leads to Progression of Tumor Phenotype in Primary Retinal Pigment Epithelial Cells

PubMed Central

Gnana-Prakasam, Jaya P.; Veeranan-Karmegam, Rajalakshmi; Coothankandaswamy, Veena; Reddy, Sushma K.; Martin, Pamela M.; Thangaraju, Muthusamy; Smith, Sylvia B.; Ganapathy, Vadivel

2013-01-01

Purpose. Hemochromatosis is a disorder of iron overload arising mostly from mutations in HFE. HFE is expressed in retinal pigment epithelium (RPE), and Hfe−/− mice develop age-related iron accumulation and retinal degeneration associated with RPE hyperproliferation. Here, the mechanism underlying the hyperproliferative phenotype in RPE was investigated. Methods. Cellular senescence was monitored by β-galactosidase activity. Gene expression was monitored by real-time PCR. Survivin was analyzed by Western blot and immunofluorescence. Migration and invasion were monitored using appropriate kits. Glucose transporters (GLUTs) were monitored by 3-O-methyl-D-glucose uptake. Histone deacetylases (HDACs) were studied by monitoring catalytic activity and acetylation status of histones H3/H4. Results. Hfe−/− RPE cells exhibited slower senescence rate and higher survivin expression than wild type cells. Hfe−/− cells migrated faster and showed greater glucose uptake and increased expression of GLUTs. The expression of HDACs and DNA methyltransferase (DNMTs) also was increased. Similarly, RPE cells from hemojuvelin (Hjv)-knockout mice, another model of hemochromatosis, also had increased expression of GLUTs, HDACs, and DNMTs. The expression of Slc5a8 was decreased in Hfe−/− RPE cells, but treatment with a DNA methylation inhibitor restored the transporter expression, indicating involvement of DNA methylation in the silencing of Slc5a8 in Hfe−/− cells. Conclusions. RPE cells from iron-overloaded mice exhibit several features of tumor cells: decreased senescence, enhanced migration, increased glucose uptake, and elevated levels of HDACs and DNMTs. These features are seen in Hfe−/− RPE cells as well as in Hjv−/− RPE cells, providing a molecular basis for the hyperproliferative phenotype of Hfe−/− and Hjv−/− RPE cells. PMID:23169885

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.

Chronic myelomonocytic leukemia masquerading as cutaneous indeterminate dendritic cell tumor: Expanding the spectrum of skin lesions in chronic myelomonocytic leukemia.

PubMed

Loghavi, Sanam; Curry, Jonathan L; Garcia-Manero, Guillermo; Patel, Keyur P; Xu, Jie; Khoury, Joseph D; Torres-Cabala, Carlos A; Nagarajan, Priyadharsini; Aung, Phyu P; Gibson, Bernard R; Goodwin, Brandon P; Kelly, Brent C; Korivi, Brinda R; Medeiros, L Jeffrey; Prieto, Victor G; Kantarjian, Hagop M; Bueso-Ramos, Carlos E; Tetzlaff, Michael T

2017-12-01

Chronic myelomonocytic leukemia (CMML) is a hematopoietic stem cell neoplasm exhibiting both myelodysplastic and myeloproliferative features. Cutaneous involvement by CMML is critical to recognize as it typically is a harbinger of disease progression and an increased incidence of transformation to acute myeloid leukemia. Cutaneous lesions of CMML exhibit heterogeneous histopathologic features that can be challenging to recognize as CMML. We describe a 67-year-old man with a 3-year history of CMML who had been managed on single-agent azacitidine with stable disease before developing splenomegaly and acute onset skin lesions. Examination of these skin lesions revealed a dense infiltrate of histiocytic cells morphologically resembling Langerhans type cells (lacking frank histopathologic atypia), and with the immunophenotype of an indeterminate cell histiocytosis (S100+ CD1a+ and langerin-). Given the history of CMML, next-generation sequencing studies were performed on the skin biopsy. These revealed a KRAS (p.G12R) mutation identical to that seen in the CMML 3 years prior, establishing a clonal relationship between the 2 processes. This case expands the spectrum for and underscores the protean nature of cutaneous involvement by CMML and underscores the importance of heightened vigilance when evaluating skin lesions of CMML patients. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Expression of Immunoglobulin Receptors with Distinctive Features Indicating Antigen Selection by Marginal Zone B Cells from Human Spleen

PubMed Central

Colombo, Monica; Cutrona, Giovanna; Reverberi, Daniele; Bruno, Silvia; Ghiotto, Fabio; Tenca, Claudya; Stamatopoulos, Kostas; Hadzidimitriou, Anastasia; Ceccarelli, Jenny; Salvi, Sandra; Boccardo, Simona; Calevo, Maria Grazia; De Santanna, Amleto; Truini, Mauro; Fais, Franco; Ferrarini, Manlio

2013-01-01

Marginal zone (MZ) B cells, identified as surface (s)IgMhighsIgDlowCD23low/−CD21+CD38− B cells, were purified from human spleens, and the features of their V(D)J gene rearrangements were investigated and compared with those of germinal center (GC), follicular mantle (FM) and switched memory (SM) B cells. Most MZ B cells were CD27+ and exhibited somatic hypermutations (SHM), although to a lower extent than SM B cells. Moreover, among MZ B-cell rearrangements, recurrent sequences were observed, some of which displayed intraclonal diversification. The same diversifying sequences were detected in very low numbers in GC and FM B cells and only when a highly sensitive, gene-specific polymerase chain reaction was used. This result indicates that MZ B cells could expand and diversify in situ and also suggested the presence of a number of activation-induced cytidine deaminase (AID)-expressing B cells in the MZ. The notion of antigen-driven expansion/selection in situ is further supported by the VH CDR3 features of MZ B cells with highly conserved amino acids at specific positions and by the finding of shared (“stereotyped”) sequences in two different spleens. Collectively, the data are consistent with the notion that MZ B cells are a special subset selected by in situ antigenic stimuli. PMID:23877718

Targetable genetic features of primary testicular and primary central nervous system lymphomas

PubMed Central

Chapuy, Bjoern; Roemer, Margaretha G. M.; Stewart, Chip; Tan, Yuxiang; Abo, Ryan P.; Zhang, Liye; Dunford, Andrew J.; Meredith, David M.; Thorner, Aaron R.; Jordanova, Ekaterina S.; Liu, Gang; Feuerhake, Friedrich; Ducar, Matthew D.; Illerhaus, Gerald; Gusenleitner, Daniel; Linden, Erica A.; Sun, Heather H.; Homer, Heather; Aono, Miyuki; Pinkus, Geraldine S.; Ligon, Azra H.; Ligon, Keith L.; Ferry, Judith A.; Freeman, Gordon J.; van Hummelen, Paul; Golub, Todd R.; Getz, Gad; Rodig, Scott J.; de Jong, Daphne; Monti, Stefano

2016-01-01

Primary central nervous system lymphomas (PCNSLs) and primary testicular lymphomas (PTLs) are extranodal large B-cell lymphomas (LBCLs) with inferior responses to current empiric treatment regimens. To identify targetable genetic features of PCNSL and PTL, we characterized their recurrent somatic mutations, chromosomal rearrangements, copy number alterations (CNAs), and associated driver genes, and compared these comprehensive genetic signatures to those of diffuse LBCL and primary mediastinal large B-cell lymphoma (PMBL). These studies identify unique combinations of genetic alterations in discrete LBCL subtypes and subtype-selective bases for targeted therapy. PCNSLs and PTLs frequently exhibit genomic instability, and near-uniform, often biallelic, CDKN2A loss with rare TP53 mutations. PCNSLs and PTLs also use multiple genetic mechanisms to target key genes and pathways and exhibit near-uniform oncogenic Toll-like receptor signaling as a result of MYD88 mutation and/or NFKBIZ amplification, frequent concurrent B-cell receptor pathway activation, and deregulation of BCL6. Of great interest, PCNSLs and PTLs also have frequent 9p24.1/PD-L1/PD-L2 CNAs and additional translocations of these loci, structural bases of immune evasion that are shared with PMBL. PMID:26702065

Nanofluidics in cellular tubes under oscillatory extension

NASA Astrophysics Data System (ADS)

Nassoy, P.; Cuvelier, D.; Bruinsma, R.; Brochard-Wyart, F.

2008-10-01

Membrane nanotubes or tethers extruded from cells exhibit dynamic features that are believed to exhibit viscoelastic rheological properties. We have performed typical microrheology experiments on tethers pulled from red blood cells by measuring the force response to small oscillatory extensions or compressions. Our data, supported by a simple theoretical model, show that the force response does not reflect any intrinsic viscoelastic properties of the tethers themselves, but instead is dominated by the drainage of the internal cellular fluid into and out of the oscillating nanoconduit over a frequency-dependent penetration depth. The simplicity of tether rheology suggests its usage as a probe for measuring the local viscosity of the cytosol near the plasma membrane.

Material- and feature-dependent effects on cell adhesion to micro injection moulded medical polymers.

PubMed

Choi, Seong Ying; Habimana, Olivier; Flood, Peter; Reynaud, Emmanuel G; Rodriguez, Brian J; Zhang, Nan; Casey, Eoin; Gilchrist, Michael D

2016-09-01

Two polymers, polymethylmethacrylate (PMMA) and cyclic olefin copolymer (COC), containing a range of nano- to micron- roughness surfaces (Ra 0.01, 0.1, 0.4, 1.0, 2.0, 3.2 and 5.0μm) were fabricated using electrical discharge machining (EDM) and replicated using micro injection moulding (μIM). Polymer samples were characterized using optical profilometry, atomic force microscopy (AFM) and water surface contact angle. Cell adhesion tests were carried out using bacterial Pseudomonas fluorescens and mammalian Madin-Darby Canine Kidney (MDCK) cells to determine the effect of surface hydrophobicity, surface roughness and stiffness. It is found that there are features which gave insignificant differences (feature-dependent effect) in cell adhesion, albeit a significant difference in the physicochemical properties (material-dependent effect) of substrata. In bacterial cell adhesion, the strongest feature-dependence is found at Ra 0.4μm surfaces, with material-dependent effects strongest at Ra 0.01μm. Ra 0.1μm surfaces exhibited strongest feature-dependent effects and Ra 5.0μm has strongest material-dependent effects on mammalian cell adhesion. Bacterial cell adhesion is found to be favourable to hydrophobic surfaces (COC), with the lowest adhesion at Ra 0.4μm for both materials. Mammalian cell adhesion is lowest in Ra 0.1μm and highest in Ra 1.0μm, and generally favours hydrophilic surfaces (PMMA). These findings can be used as a basis for developing medical implants or microfluidic devices using micro injection moulding for diagnostic purposes, by tuning the cell adhesion on different areas containing different surface roughnesses on the diagnostic microfluidic devices or medical implants. Copyright © 2016 Elsevier B.V. All rights reserved.

DUX4 Immunohistochemistry Is a Highly Sensitive and Specific Marker for CIC-DUX4 Fusion-positive Round Cell Tumor.

PubMed

Siegele, Bradford; Roberts, Jon; Black, Jennifer O; Rudzinski, Erin; Vargas, Sara O; Galambos, Csaba

2017-03-01

The histologic differential diagnosis of pediatric and adult round cell tumors is vast and includes the recently recognized entity CIC-DUX4 fusion-positive round cell tumor. The diagnosis of CIC-DUX4 tumor can be suggested by light microscopic and immunohistochemical features, but currently, definitive diagnosis requires ancillary genetic testing such as conventional karyotyping, fluorescence in situ hybridization, or molecular methods. We sought to determine whether DUX4 expression would serve as a fusion-specific immunohistochemical marker distinguishing CIC-DUX4 tumor from potential histologic mimics. A cohort of CIC-DUX4 fusion-positive round cell tumors harboring t(4;19)(q35;q13) and t(10;19)(q26;q13) translocations was designed, with additional inclusion of a case with a translocation confirmed to involve the CIC gene without delineation of the partner. Round cell tumors with potentially overlapping histologic features were also collected. Staining with a monoclonal antibody raised against the C-terminus of the DUX4 protein was applied to all cases. DUX4 immunohistochemistry exhibited diffuse, crisp, strong nuclear staining in all CIC-DUX4 fusion-positive round cell tumors (5/5, 100% sensitivity), and exhibited negative staining in nuclei of all of the other tested round cell tumors, including 20 Ewing sarcomas, 1 Ewing-like sarcoma, 11 alveolar rhabdomyosarcomas, 9 embryonal rhabdomyosarcomas, 12 synovial sarcomas, 7 desmoplastic small round cell tumors, 3 malignant rhabdoid tumors, 9 neuroblastomas, and 4 clear cell sarcomas (0/76, 100% specificity). Thus, in our experience, DUX4 immunostaining distinguishes CIC-DUX4 tumors from other round cell mimics. We recommend its use when CIC-DUX4 fusion-positive round cell tumor enters the histologic differential diagnosis.

Postirradiation malignant fibrous histiocytoma of the lung. Demonstration of alpha 1-antitrypsin-like material in neoplastic cells.

PubMed

Chowdhury, L N; Swerdlow, M A; Jao, W; Kathpalia, S; Desser, R K

1980-12-01

A metastasizing fibrous histiocytoma arising in the lung of a patient who received radiation therapy and long-term chemotherapy for malignant lymphoma is presented. Ultrastructural studies revealed fibroblast-like and histiocyte-like cells, cells of intermediate type showing ultrastructural features of both fibroblast-like and histiocyte-like cells, primitive mesenchymal cells, multinucleate tumor cells, and xanthomatous cells. The neoplastic cells showed dilated rough endoplasmic reticula with intracisternal accumulation of electron-dense material forming lattice-like structures. Direct immunofluorescence staining of the neoplastic cells using antihuman alpha 1-antitrypsin showed specific activity, with fluorescent deposits exhibiting interlacing globular formations. These findings and their implications are discussed.

Quantitative and qualitative features of heterologous virus-vector-induced antigen-specific CD8+ T cells against Trypanosoma cruzi infection.

PubMed

Takayama, Eiji; Ono, Takeshi; Carnero, Elena; Umemoto, Saori; Yamaguchi, Yoko; Kanayama, Atsuhiro; Oguma, Takemi; Takashima, Yasuhiro; Tadakuma, Takushi; García-Sastre, Adolfo; Miyahira, Yasushi

2010-11-01

We studied some aspects of the quantitative and qualitative features of heterologous recombinant (re) virus-vector-induced, antigen-specific CD8(+) T cells against Trypanosoma cruzi. We used three different, highly attenuated re-viruses, i.e., influenza virus, adenovirus and vaccinia virus, which all expressed a single, T. cruzi antigen-derived CD8(+) T-cell epitope. The use of two out of three vectors or the triple virus-vector vaccination regimen not only confirmed that the re-vaccinia virus, which was placed last in order for sequential immunisation, was an effective booster for the CD8(+) T-cell immunity in terms of the number of antigen-specific CD8(+) T cells, but also demonstrated that (i) the majority of cells exhibit the effector memory (T(EM)) phenotype, (ii) robustly secrete IFN-γ, (iii) express higher intensity of the CD122 molecule and (iv) present protective activity against T. cruzi infection. In contrast, placing the re-influenza virus last in sequential immunisation had a detrimental effect on the quantitative and qualitative features of CD8(+) T cells. The triple virus-vector vaccination was more effective at inducing a stronger CD8(+) T-cell immunity than using two re-viruses. The different quantitative and qualitative features of CD8(+) T cells induced by different immunisation regimens support the notion that the refinement of the best choice of multiple virus-vector combinations is indispensable for the induction of a maximum number of CD8(+) T cells of high quality. Copyright © 2010 Australian Society for Parasitology Inc. All rights reserved.

Targeting Adenosine A2A Receptors in Parkinson’s Disease

DTIC Science & Technology

2006-11-01

events, which are important for information processing within the nucleus accumbens and more largely in the striatum, should have a high impact on basal...half that of men who do not consume caffeine, whereas consumption of decaffeinated coffee is unrelated to PD risk. Results among women, however, are...immunopositive cells showed swollen and hyper-trophic cell bodies as well as processes and exhibited morphological features of activated microglia. In the

Cell communities and robustness in development.

PubMed

Monk, N A

1997-11-01

The robustness of patterning events in development is a key feature that must be accounted for in proposed models of these events. When considering explicitly cellular systems, robustness can be exhibited at different levels of organization. Consideration of two widespread patterning mechanisms suggests that robustness at the level of cell communities can result from variable development at the level of individual cells; models of these mechanisms show how interactions between participating cells guarantee community-level robustness. Cooperative interactions enhance homogeneity within communities of like cells and the sharpness of boundaries between communities of distinct cells, while competitive interactions amplify small inhomogeneities within communities of initially equivalent cells, resulting in fine-grained patterns of cell specialization.

Coupling of lipid membrane elasticity and in-plane dynamics

NASA Astrophysics Data System (ADS)

Tsang, Kuan-Yu; Lai, Yei-Chen; Chiang, Yun-Wei; Chen, Yi-Fan

2017-07-01

Biomembranes exhibit liquid and solid features concomitantly with their in-plane fluidity and elasticity tightly regulated by cells. Here, we present experimental evidence supporting the existence of the dynamics-elasticity correlations for lipid membranes and propose a mechanism involving molecular packing densities to explain them. This paper thereby unifies, at the molecular level, the aspects of the continuum mechanics long used to model the two membrane features. This ultimately may elucidate the universal physical principles governing the cellular phenomena involving biomembranes.

Energy management by enhanced glycolysis in G1-phase in human colon cancer cells in vitro and in vivo.

PubMed

Bao, Yan; Mukai, Kuniaki; Hishiki, Takako; Kubo, Akiko; Ohmura, Mitsuyo; Sugiura, Yuki; Matsuura, Tomomi; Nagahata, Yoshiko; Hayakawa, Noriyo; Yamamoto, Takehiro; Fukuda, Ryo; Saya, Hideyuki; Suematsu, Makoto; Minamishima, Yoji Andrew

2013-09-01

Activation of aerobic glycolysis in cancer cells is well known as the Warburg effect, although its relation to cell- cycle progression remains unknown. In this study, human colon cancer cells were labeled with a cell-cycle phase-dependent fluorescent marker Fucci to distinguish cells in G1-phase and those in S + G2/M phases. Fucci-labeled cells served as splenic xenograft transplants in super-immunodeficient NOG mice and exhibited multiple metastases in the livers, frozen sections of which were analyzed by semiquantitative microscopic imaging mass spectrometry. Results showed that cells in G1-phase exhibited higher concentrations of ATP, NADH, and UDP-N-acetylglucosamine than those in S and G2-M phases, suggesting accelerated glycolysis in G1-phase cells in vivo. Quantitative determination of metabolites in cells synchronized in S, G2-M, and G1 phases suggested that efflux of lactate was elevated significantly in G1-phase. By contrast, ATP production in G2-M was highly dependent on mitochondrial respiration, whereas cells in S-phase mostly exhibited an intermediary energy metabolism between G1 and G2-M phases. Isogenic cells carrying a p53-null mutation appeared more active in glycolysis throughout the cell cycle than wild-type cells. Thus, as the cell cycle progressed from G2-M to G1 phases, the dependency of energy production on glycolysis was increased while the mitochondrial energy production was reciprocally decreased. These results shed light on distinct features of the phase-specific phenotypes of metabolic systems in cancer cells. ©2013 AACR.

Azide derivatized anticancer agents of Vitamin K 3: X-ray structural, DSC, resonance spectral and API studies

NASA Astrophysics Data System (ADS)

Badave, Kirti; Patil, Yogesh; Gonnade, Rajesh; Srinivas, Darbha; Dasgupta, Rajan; Khan, Ayesha; Rane, Sandhya

2011-12-01

Compound 1 [1-imino (acetyl hydrazino)-Vitamin K 3], displays valence tautomerically related electronic isomers as Form I and Form II. Form I exhibits 2D packing fragment with 1D ribbon chains of N-H⋯O hydrogen bonds and shows EPR silent features. While Form II is EPR active and exhibits biradical nature with double quantum transitions at g = 2.0040. 1H NMR of compound 2, [1-imino (hydrazino carboxylate)-Vitamin K 3] and Form II exhibit π delocalization via resonance assisted H-bonding [RAHB] effect compared to Form I. Molecular interactions in Form I and II are visualized by DSC. The electronic structures of compounds 1 and 2 have been correlated to their API values by measuring anticancer activities, mitochondrial potentials and DNA shearing patterns. Form II and compound 2 indicate mitochondria mediated apoptosis (˜75% cell death) while Form I causes 35% cell death.

Cyto-histopathological and outcome features of the prepuce squamous cell carcinoma of a mixed breed dog

PubMed Central

2014-01-01

Abstract Background Squamous cell carcinomas (SCCs) are uncommon, high-grade tumors, predominantly composed of round cells in the prepuce. The aim of this study is to better define the clinicopathologic features of this neoplasm. Case report We conducted cyto-histopathologic analysis on the manifestations of the prepuce SCC by H & E staining in a terrier mix dog. Grossly, tumor was large, multiple erythematous patch, and ulcerated masses frequently affecting the prepuce and deeply invading to distal prepuce out from the ventro-lateral of penis and the tumor covered by a necrotic discharge. Cytological evaluation of fine-needle aspirates from the cutaneous mass from the prepuce comprised of round nuclei, coarse chromatin pattern, distinct nucleoli and nuclear pleomorphism. Furthermore, the neoplastic cells were pleomorphic, round to caudate in shape, exhibiting prominent anisokaryosis and anisocytosis with rare mitotic features. Microscopically, the lesions were predominantly composed of atypical round cells disposed in interlacing fascicles. Frequent findings include keratin formation, horn pearls, mitoses and cellular atypia. The cells showed distinct borders, ranged from polygonal to round or elongate and had moderate amounts of eosinophilic cytoplasm. Conclusion The histopathologic features coupled with the cytopathology findings led to a diagnosis of squamous cell carcinoma. To the authors’ knowledge, this is the first time that multiple erythematous plaques have undergone malignant transformation in a terrier mix dog. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5748771971272873 PMID:24903567

Mesoporous stilbene-based lanthanide metal organic frameworks: synthesis, photoluminescence and radioluminescence characteristics.

PubMed

Mathis Ii, Stephan R; Golafale, Saki T; Bacsa, John; Steiner, Alexander; Ingram, Conrad W; Doty, F Patrick; Auden, Elizabeth; Hattar, Khalid

2017-01-03

Ultra large pore isostructural metal organic frameworks (MOFs) which exhibit both photoluminescence and scintillation properties, were synthesized from trans-4,4'-stilbenedicarboxylic acid (H 2 L) and trivalent lanthanide (Ln) metal salts under solvothermal conditions (Ln = Er 3+ (1) and Tm 3+ (2)). This new class of mesoporous materials is a non-interpenetrating network that features ultra-large diamond shaped pores of dimensions with approximate cross-sectional dimensions of 28 Å × 12 Å. The fully deprotonated ligand, L, is isolated and rigidified as it serves as the organic linker component of the MOF structure. Its low density unit cells possess asymmetric units with two crystallographically independent Ln 3+ ions in seven coordinate arrangements. A distinct feature of the structure is the bis-bidentate carboxylate groups. They serve as a ligand that coordinates two Ln(iii) ions while each L connects four Ln(iii) ions yielding an exceptionally large diamond-shaped rectangular network. The structure exhibits ligand-based photoluminescence with increased lifetime compared to free stilbene molecules on exposure to UV radiation, and also exhibits strong scintillation characteristics, comprising of both prompt and delayed radioluminescence features, on exposure to ionizing radiation.

Silicon Whisker and Carbon Nanofiber Composite Anode

NASA Technical Reports Server (NTRS)

Lang, Christopher M.

2015-01-01

Phase II Objectives: Demonstrate production levels of grams per batch; Achieve full cell anode capacity of greater than 1,000 mAh/g at a charge rate of 10 (C/10) and 0 degree C; Establish a full cell cycle life of over 300 cycles; Display an operating temperature of negative 30 degrees C to plus 30 degrees C; Demonstrate a rate capability of C/5 or higher; Deliver to NASA three 2.5 Ah cells (energy density greater than 220 Wh/kg); Exhibit the safety features of the anode and full cells; Design a 1 kWh prismatic battery pack.

Nanometer polymer surface features: the influence on surface energy, protein adsorption and endothelial cell adhesion

NASA Astrophysics Data System (ADS)

Carpenter, Joseph; Khang, Dongwoo; Webster, Thomas J.

2008-12-01

Current small diameter (<5 mm) synthetic vascular graft materials exhibit poor long-term patency due to thrombosis and intimal hyperplasia. Tissue engineered solutions have yielded functional vascular tissue, but some require an eight-week in vitro culture period prior to implantation—too long for immediate clinical bedside applications. Previous in vitro studies have shown that nanostructured poly(lactic-co-glycolic acid) (PLGA) surfaces elevated endothelial cell adhesion, proliferation, and extracellular matrix synthesis when compared to nanosmooth surfaces. Nonetheless, these studies failed to address the importance of lateral and vertical surface feature dimensionality coupled with surface free energy; nor did such studies elicit an optimum specific surface feature size for promoting endothelial cell adhesion. In this study, a series of highly ordered nanometer to submicron structured PLGA surfaces of identical chemistry were created using a technique employing polystyrene nanobeads and poly(dimethylsiloxane) (PDMS) molds. Results demonstrated increased endothelial cell adhesion on PLGA surfaces with vertical surface features of size less than 18.87 nm but greater than 0 nm due to increased surface energy and subsequently protein (fibronectin and collagen type IV) adsorption. Furthermore, this study provided evidence that the vertical dimension of nanometer surface features, rather than the lateral dimension, is largely responsible for these increases. In this manner, this study provides key design parameters that may promote vascular graft efficacy.

Clinicopathological features of pulmonary cryptococcosis with cryptococcal titan cells: a comparative analysis of 27 cases.

PubMed

Wang, Jing-Mei; Zhou, Qiang; Cai, Hou-Rong; Zhuang, Yi; Zhang, Yi-Fen; Xin, Xiao-Yan; Meng, Fan-Qing; Wang, Ya-Ping

2014-01-01

In addition to the typical size, Cryptococcus neoformans can enlarge its size to form titan cells during infection, and its diameter can reach up to 100 μm. Clinical reports about cryptococcal titan cells are rare. Most studies focus on aspects of animal models of infection with titan cells. Herein, we report the clinical and imaging characteristics and histopathologic features of 3 patients with titan cells and 27 patients with pathogens of typical size, and describe the morphological characteristics of titan cells in details. Histologically, 3 patients with titan cells show necrosis, fibrosis and macrophage accumulation. The titan cells appear in necrotic tissue and between macrophages, and have thick wall with unstained halo around them and diameters range from 20 to 80 μm with characteristic of narrow-necked single budding. There are also organisms with typical size. All 27 patients with normal pathogens show epithelioid granulomatous lesions. There is no significantly difference in clinical and imaging feature between the two groups. Cryptococcus neoformans exhibits a striking morphological change for the formation of titan cells during pulmonary infection, which will result in misdiagnosis and under diagnosis. The histopathological changes may be new manifestation, which need to be further confirmed by the study with animal models of infection and the observation of more clinical cases. Careful observation of the tissue sections is necessary.

Real space flight travel is associated with ultrastructural changes, cytoskeletal disruption and premature senescence of HUVEC.

PubMed

Kapitonova, M Y; Muid, S; Froemming, G R A; Yusoff, W N W; Othman, S; Ali, A M; Nawawi, H M

2012-12-01

Microgravity, hypergravity, vibration, ionizing radiation and temperature fluctuations are major factors of outer space flight affecting human organs and tissues. There are several reports on the effect of space flight on different human cell types of mesenchymal origin while information regarding changes to vascular endothelial cells is scarce. Ultrastructural and cytophysiological features of macrovascular endothelial cells in outer space flight and their persistence during subsequent culturing were demonstrated in the present investigation. At the end of the space flight, endothelial cells displayed profound changes indicating cytoskeletal lesions and increased cell membrane permeability. Readapted cells of subsequent passages exhibited persisting cytoskeletal changes, decreased metabolism and cell growth indicating cellular senescence.

Glycosylation and immunocytochemistry of binucleate cells in pronghorn (Antilocapra americana, Antilocapridae) show features of both Giraffidae and Bovidae.

PubMed

Jones, Carolyn J P; Silvia, W J; Hamilton, C H; Geary, T W; Zezeski, A L; Wooding, F B P

2017-09-01

Although the pronghorn (Antilocapra americana) resembles an antelope, its nearest relatives are the giraffe and okapi. In this study we have examined the placentae of 6 pronghorns using lectin- and immunocytochemistry to identify giraffid and bovid features. Binucleate cells (BNC) of the placenta exhibited features intermediate between those of the giraffe and bovine; Dolichos biflorus agglutinin binding - strong in the bovine BNC and absent in the giraffe - was evident in only a subpopulation of BNC while binding to blood vessels, as in the giraffe. Binding of Phytolacca americana agglutinin resembled that of the giraffe and okapi whereas many other glycans were found in all four clades. PAG antigens were similar to bovine and okapi but not giraffe. In summary, although the pronghorn outwardly resembles an antelope, placental BNC show giraffid features. Although each clade has its own individual characteristics, there are far more similarities than differences between them, emphasizing the common ancestry of all four clades. Copyright © 2017 Elsevier Ltd. All rights reserved.

A generalized reaction diffusion model for spatial structure formed by motile cells.

PubMed

Ochoa, F L

1984-01-01

A non-linear stability analysis using a multi-scale perturbation procedure is carried out on a model of a generalized reaction diffusion mechanism which involves only a single equation but which nevertheless exhibits bifurcation to non-uniform states. The patterns generated by this model by variation in a parameter related to the scalar dimensions of domain of definition, indicate its capacity to represent certain key morphogenetic features of multicellular systems formed by motile cells.

Complex, multi-scale small intestinal topography replicated in cellular growth substrates fabricated via chemical vapor deposition of Parylene C.

PubMed

Koppes, Abigail N; Kamath, Megha; Pfluger, Courtney A; Burkey, Daniel D; Dokmeci, Mehmet; Wang, Lin; Carrier, Rebecca L

2016-08-22

Native small intestine possesses distinct multi-scale structures (e.g., crypts, villi) not included in traditional 2D intestinal culture models for drug delivery and regenerative medicine. The known impact of structure on cell function motivates exploration of the influence of intestinal topography on the phenotype of cultured epithelial cells, but the irregular, macro- to submicron-scale features of native intestine are challenging to precisely replicate in cellular growth substrates. Herein, we utilized chemical vapor deposition of Parylene C on decellularized porcine small intestine to create polymeric intestinal replicas containing biomimetic irregular, multi-scale structures. These replicas were used as molds for polydimethylsiloxane (PDMS) growth substrates with macro to submicron intestinal topographical features. Resultant PDMS replicas exhibit multiscale resolution including macro- to micro-scale folds, crypt and villus structures, and submicron-scale features of the underlying basement membrane. After 10 d of human epithelial colorectal cell culture on PDMS substrates, the inclusion of biomimetic topographical features enhanced alkaline phosphatase expression 2.3-fold compared to flat controls, suggesting biomimetic topography is important in induced epithelial differentiation. This work presents a facile, inexpensive method for precisely replicating complex hierarchal features of native tissue, towards a new model for regenerative medicine and drug delivery for intestinal disorders and diseases.

From 2D to 3D: The morphology, proliferation and differentiation of MC3T3-E1 on silk fibroin/chitosan matrices.

PubMed

Li, Da-Wei; He, Feng-Li; He, Jin; Deng, Xudong; Liu, Ya-Li; Liu, Yang-Yang; Ye, Ya-Jing; Yin, Da-Chuan

2017-12-15

It has been widely accepted that cell culture in two-dimensional (2D) conditions may not be able to represent growth in three-dimensional (3D) conditions. Systematic comparisons between 2D and 3D cell cultures are needed to appropriately use the existing 2D results. In this work, we conducted a comparative study between 2D and 3D cell cultures of MC3T3-E1 using the same type of material (a mixture of silk fibroin (SF) and chitosan (CS)). Our results showed 3D SF/CS scaffold exhibited different effects on cell culture compared with the 2D cases. 1) The cells grown in 3D scaffold showed multiple morphologies. 2) The proliferation of cells in 3D scaffold was long-term and sustainable. 3) Cell differentiation occurred throughout the entire 3D scaffold. The results showed that cell culture in 3D SF/CS scaffold exhibited different features than 2D cases and 3D SF/CS scaffold could be a promising material for 3D cell culture. Copyright © 2017 Elsevier Ltd. All rights reserved.

EGFR, ALK, RET, KRAS and BRAF alterations in never-smokers with non-small cell lung cancer.

PubMed

Dong, Y U; Ren, Weihong; Qi, Jun; Jin, B O; Li, Ying; Tao, Huiqing; Xu, Ren; Li, Yanqing; Zhang, Qinxian; Han, Baohui

2016-04-01

Non-small cell lung cancer (NSCLC), caused by various mutations in a spectrum of cancer driver genes, may have distinct pathological characteristics and drug responses. Extensive genetic screening and pathological characterization is required for the design of customized therapies to improve patient outcomes. Notably, NSCLC in never-smokers exhibits distinctive clinicopathological features, which are frequently associated with tumorigenic mutations, and thus may be treated as a unique disease entity. However, to the best of our knowledge, these mutations have not been extensively and accurately characterized in an NSCLC study with a large sample size. Therefore, the present study enrolled a large cohort of NSCLC patients, which consisted of 358 never-smokers, for the screening of genetic alterations in the epidermal growth factor receptor (EGFR), ret proto-oncogene (RET), anaplastic lymphoma kinase (ALK), Kirsten rat sarcoma viral oncogene homolog (KRAS) and B-Raf proto-oncogene serine/threonine kinase (BRAF) tumorigenic genes. It was identified that the mutation rate was 47.8, 7.5, 3.6, 1.4 and 0.3% for EGFR, ALK, KRAS, RET and BRAF, respectively. In addition, clinicopathological features associated with these mutations were characterized. EGFR mutations were more frequently observed in female and older patients. By contrast, KRAS mutations were more frequently detected in male patients, and ALK and RET translocations in younger patients. The cancer cells were frequently well-differentiated in carcinoma cases exhibiting EGFR mutations, however, were less differentiated in those with ALK translocations. In conclusion, the present study determined the frequency of oncogenic alterations and associated clinicopathological features in NSCLC exhibited by never-smokers using a large sample size. The results of the present study may enrich our knowledge of NSCLC in never-smokers and provide useful insights for improvement of the outcome of molecularly targeted therapies for the treatment of NSCLC.

Dynamic biophotonics: female squid exhibit sexually dimorphic tunable leucophores and iridocytes.

PubMed

DeMartini, Daniel G; Ghoshal, Amitabh; Pandolfi, Erica; Weaver, Aaron T; Baum, Mary; Morse, Daniel E

2013-10-01

Loliginid squid use tunable multilayer reflectors to modulate the optical properties of their skin for camouflage and communication. Contained inside specialized cells called iridocytes, these photonic structures have been a model for investigations into bio-inspired adaptive optics. Here, we describe two distinct sexually dimorphic tunable biophotonic features in the commercially important species Doryteuthis opalescens: bright stripes of rainbow iridescence on the mantle just beneath each fin attachment and a bright white stripe centered on the dorsal surface of the mantle between the fins. Both of these cellular features are unique to the female; positioned in the same location as the conspicuously bright white testis in the male, they are completely switchable, transitioning between transparency and high reflectivity. The sexual dimorphism, location and tunability of these features suggest that they may function in mating or reproduction. These features provide advantageous new models for investigation of adaptive biophotonics. The intensely reflective cells of the iridescent stripes provide a greater signal-to-noise ratio than the adaptive iridocytes studied thus far, while the cells constituting the white stripe are adaptive leucophores--unique biological tunable broadband scatterers containing Mie-scattering organelles activated by acetylcholine, and a unique complement of reflectin proteins.

Titan Cell Production Enhances the Virulence of Cryptococcus neoformans

PubMed Central

Crabtree, Juliet N.; Okagaki, Laura H.; Wiesner, Darin L.; Strain, Anna K.; Nielsen, Judith N.

2012-01-01

Infection with Cryptococcus neoformans begins when desiccated yeast cells or spores are inhaled and lodge in the alveoli of the lungs. A subset of cryptococcal cells in the lungs differentiate into enlarged cells, referred to as titan cells. Titan cells can be as large as 50 to 100 μm in diameter and exhibit a number of features that may affect interactions with host immune defenses. To characterize the effect of titan cell formation on the host-pathogen interaction, we utilized a previously described C. neoformans mutant, the gpr4Δ gpr5Δ mutant, which has minimal titan cell production in vivo. The gpr4Δ gpr5Δ mutant strain had attenuated virulence, a lower CFU, and reduced dissemination compared to the wild-type strain. Titan cell production by the wild-type strain also resulted in increased eosinophil accumulation and decreased phagocytosis in the lungs compared to those with the gpr4Δ gpr5Δ mutant strain. Phagocytosed cryptococcal cells exhibited less viability than nonphagocytosed cells, which potentially explains the reduced cell survival and overall attenuation of virulence in the absence of titan cells. These data show that titan cell formation is a novel virulence factor in C. neoformans that promotes establishment of the initial pulmonary infection and plays a key role in disease progression. PMID:22890995

Titan cell production enhances the virulence of Cryptococcus neoformans.

PubMed

Crabtree, Juliet N; Okagaki, Laura H; Wiesner, Darin L; Strain, Anna K; Nielsen, Judith N; Nielsen, Kirsten

2012-11-01

Infection with Cryptococcus neoformans begins when desiccated yeast cells or spores are inhaled and lodge in the alveoli of the lungs. A subset of cryptococcal cells in the lungs differentiate into enlarged cells, referred to as titan cells. Titan cells can be as large as 50 to 100 μm in diameter and exhibit a number of features that may affect interactions with host immune defenses. To characterize the effect of titan cell formation on the host-pathogen interaction, we utilized a previously described C. neoformans mutant, the gpr4Δ gpr5Δ mutant, which has minimal titan cell production in vivo. The gpr4Δ gpr5Δ mutant strain had attenuated virulence, a lower CFU, and reduced dissemination compared to the wild-type strain. Titan cell production by the wild-type strain also resulted in increased eosinophil accumulation and decreased phagocytosis in the lungs compared to those with the gpr4Δ gpr5Δ mutant strain. Phagocytosed cryptococcal cells exhibited less viability than nonphagocytosed cells, which potentially explains the reduced cell survival and overall attenuation of virulence in the absence of titan cells. These data show that titan cell formation is a novel virulence factor in C. neoformans that promotes establishment of the initial pulmonary infection and plays a key role in disease progression.

Multilayered membranes with tuned well arrays to be used as regenerative patches.

PubMed

Martins, Nádia I; Sousa, Maria P; Custódio, Catarina A; Pinto, Vânia C; Sousa, Paulo J; Minas, Graça; Cleymand, Franck; Mano, João F

2017-07-15

Membranes have been explored as patches in tissue repair and regeneration, most of them presenting a flat geometry or a patterned texture at the nano/micrometer scale. Herein, a new concept of a flexible membrane featuring well arrays forming pore-like environments to accommodate cell culture is proposed. The processing of such membranes using polysaccharides is based on the production of multilayers using the layer-by-layer methodology over a patterned PDMS substrate. The detached multilayered membrane exhibits a layer of open pores at one side and a total thickness of 38±2.2µm. The photolithography technology used to produce the molds allows obtaining wells on the final membranes with a tuned shape and micro-scale precision. The influence of post-processing procedures over chitosan/alginate films with 100 double layers, including crosslinking with genipin or fibronectin immobilization, on the adhesion and proliferation of human osteoblast-like cells is also investigated. The results suggest that the presence of patterned wells affects positively cell adhesion, morphology and proliferation. In particular, it is seen that cells colonized preferentially the well regions. The geometrical features with micro to sub-millimeter patterned wells, together with the nano-scale organization of the polymeric components along the thickness of the film will allow to engineer highly versatile multilayered membranes exhibiting a pore-like microstructure in just one of the sides, that could be adaptable in the regeneration of multiple tissues. Flexible multilayered membranes containing multiple micro-reservoirs are found as potential regenerative patches. Layer-by-layer (LbL) methodology over a featured PDMS substrate is used to produce patterned membranes, composed only by natural-based polymers, that can be easily detached from the PDMS substrate. The combination of nano-scale control of the polymeric organization along the thickness of the chitosan/alginate (CHT/ALG) membranes, provided by LbL, together with the geometrical micro-scale features of the patterned membranes offers a uniqueness system that allows cells to colonize 3-dimensionally. This study provides a promising strategy to control cellular spatial organization that can face the region of the tissue to regenerate. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

PTTG1 Attenuates Drug-Induced Cellular Senescence

PubMed Central

Tong, Yunguang; Zhao, Weijiang; Zhou, Cuiqi; Wawrowsky, Kolja; Melmed, Shlomo

2011-01-01

As PTTG1 (pituitary tumor transforming gene) abundance correlates with adverse outcomes in cancer treatment, we determined mechanisms underlying this observation by assessing the role of PTTG1 in regulating cell response to anti-neoplastic drugs. HCT116 cells devoid of PTTG1 (PTTG1−/−) exhibited enhanced drug sensitivity as assessed by measuring BrdU incorporation in vitro. Apoptosis, mitosis catastrophe or DNA damage were not detected, but features of senescence were observed using low doses of doxorubicin and TSA. The number of drug-induced PTTG1−/− senescent cells increased ∼4 fold as compared to WT PTTG1-replete cells (p<0.001). p21, an important regulator of cell senescence, was induced ∼3 fold in HCT116 PTTG1−/− cells upon doxorubicin or Trichostatin A treatment. Binding of Sp1, p53 and p300 to the p21 promoter was enhanced in PTTG1−/− cells after treatment, suggesting transcriptional regulation of p21. p21 knock down abrogated the observed senescent effects of these drugs, indicating that PTTG1 likely suppresses p21 to regulate drug-induced senescence. PTTG1 also regulated SW620 colon cancer cells response to doxorubicin and TSA mediated by p21. Subcutaneously xenografted PTTG1−/− HCT116 cells developed smaller tumors and exhibited enhanced responses to doxorubicin. PTTG1−/− tumor tissue derived from excised tumors exhibited increased doxorubicin-induced senescence. As senescence is a determinant of cell responses to anti-neoplastic treatments, these findings suggest PTTG1 as a tumor cell marker to predict anti-neoplastic treatment outcomes. PMID:21858218

CD8+ recent thymic emigrants exhibit increased responses to low affinity ligands and improved access to peripheral sites of inflammation

PubMed Central

Berkley, Amy M.; Fink, Pamela J.

2014-01-01

To explore the TCR sensitivity of recent thymic emigrants (RTEs), we triggered T cells with altered peptide ligands (APLs). Upon peptide stimulation in vitro, RTEs exhibited increased TCR signal transduction, and following infection in vivo with APL-expressing bacteria, CD8 RTEs expanded to a greater extent in response to low affinity antigens than their mature T cell counterparts. RTEs skewed to short-lived effector cells in response to all APLs but were also characterized by diminished cytokine production. RTEs responding to infection expressed increased levels of VLA-4, with consequent improved entry into inflamed tissue and pathogen clearance. These positive outcomes were offset by the capacity of RTEs to elicit autoimmunity. Overall, salient features of CD8 RTE biology should inform strategies to improve neonatal vaccination and therapies for cancer and HIV, as RTEs make up a large proportion of the T cells in lymphodepleted environments. PMID:25172492

Cutting edge: CD8+ recent thymic emigrants exhibit increased responses to low-affinity ligands and improved access to peripheral sites of inflammation.

PubMed

Berkley, Amy M; Fink, Pamela J

2014-10-01

To explore the TCR sensitivity of recent thymic emigrants (RTEs), we triggered T cells with altered peptide ligands (APLs). Upon peptide stimulation in vitro, RTEs exhibited increased TCR signal transduction, and following infection in vivo with APL-expressing bacteria, CD8 RTEs expanded to a greater extent in response to low-affinity Ags than did their mature T cell counterparts. RTEs skewed to short-lived effector cells in response to all APLs but also were characterized by diminished cytokine production. RTEs responding to infection expressed increased levels of VLA-4, with consequent improved entry into inflamed tissue and pathogen clearance. These positive outcomes were offset by the capacity of RTEs to elicit autoimmunity. Overall, salient features of CD8 RTE biology should inform strategies to improve neonatal vaccination and therapies for cancer and HIV, because RTEs make up a large proportion of the T cells in lymphodepleted environments. Copyright © 2014 by The American Association of Immunologists, Inc.

Infectious dengue vesicles derived from CD61+ cells in acute patient plasma exhibited a diaphanous appearance

PubMed Central

Hsu, Alan Yi-Hui; Wu, Shang-Rung; Tsai, Jih-Jin; Chen, Po-Lin; Chen, Ya-Ping; Chen, Tsai-Yun; Lo, Yu-Chih; Ho, Tzu-Chuan; Lee, Meed; Chen, Min-Ting; Chiu, Yen-Chi; Perng, Guey Chuen

2015-01-01

The levels of neutralizing antibody to a pathogen are an effective indicator to predict efficacy of a vaccine in trial. And yet not all the trial vaccines are in line with the theory. Using dengue virus (DENV) to investigate the viral morphology affecting the predictive value, we evaluated the viral morphology in acute dengue plasma compared to that of Vero cells derived DENV. The virions in plasma were infectious and heterogeneous in shape with a “sunny-side up egg” appearance, viral RNA was enclosed with CD61+ cell-derived membrane interspersed by the viral envelope protein, defined as dengue vesicles. The unique viral features were also observed from ex vivo infected human bone marrow. Dengue vesicles were less efficiently neutralized by convalescent patient serum, compared to virions produced from Vero cells. Our results exhibit a reason why potencies of protective immunity fail in vivo and significantly impact dengue vaccine and drug development. PMID:26657027

Lymphatic endothelial cell line (CH3) from a recurrent retroperitoneal lymphangioma.

PubMed

Way, D; Hendrix, M; Witte, M; Witte, C; Nagle, R; Davis, J

1987-09-01

An endothelial cell line derived from a massive recurrent chyle-containing retroperitoneal lymphangioma was isolated in monolayer culture. Scanning and transmission electron microscopy and immunohistochemistry confirmed a close resemblance to blood vascular endothelium with typical cobblestone morphology, positive immunofluorescence staining for endothelial marker Factor VIII-associated antigen and fibronectin, and prominent Weibel-Palade bodies. The endothelial cells also exhibited other ultrastructural features characteristic of lymphatic endothelium, including sparse microvillous surface projections, overlapping intercellular junctions, and abundant intermediate filaments. This endothelial cell line represents a new source of proliferating lymphatic endothelium for future study, including structural and functional comparison to blood vascular endothelium.

Elevated Na+/H+ exchanger-1 expression enhances the metastatic collective migration of head and neck squamous cell carcinoma cells.

PubMed

Kaminota, Teppei; Yano, Hajime; Shiota, Kohei; Nomura, Noriko; Yaguchi, Haruna; Kirino, Yui; Ohara, Kentaro; Tetsumura, Issei; Sanada, Tomoyoshi; Ugumori, Toru; Tanaka, Junya; Hato, Naohito

2017-04-22

Cancer cells can migrate as collectives during invasion and/or metastasis; however, the precise molecular mechanisms of this form of migration are less clear compared with single cell migration following epithelial-mesenchymal transition. Elevated Na + /H + exchanger1 (NHE1) expression has been suggested to have malignant roles in a number of cancer cell lines and in vivo tumor models. Furthermore, a metastatic human head and neck squamous cell carcinoma (HNSCC) cell line (SASL1m) that was isolated based on its increased metastatic potential also exhibited higher NHE1 expression than its parental line SAS. Time-lapse video recordings indicated that both cell lines migrate as collectives, although with different features, e.g., SASL1m was much more active and changed the direction of migration more frequently than SAS cells, whereas locomotive activities were comparable. SASL1m cells also exhibited higher invasive activity than SAS in Matrigel invasion assays. shRNA-mediated NHE1 knockdown in SASL1m led to reduced locomotive and invasive activities, suggesting a critical role for NHE1 in the collective migration of SASL1m cells. SASL1m cells also exhibited a higher metastatic rate than SAS cells in a mouse lymph node metastasis model, while NHE1 knockdown suppressed in vivo SASL1m metastasis. Finally, elevated NHE1 expression was observed in human HNSCC tissue, and Cariporide, a specific NHE1 inhibitor, reduced the invasive activity of SASL1m cells, implying NHE1 could be a target for anti-invasion/metastasis therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Thermochromic halide perovskite solar cells.

PubMed

Lin, Jia; Lai, Minliang; Dou, Letian; Kley, Christopher S; Chen, Hong; Peng, Fei; Sun, Junliang; Lu, Dylan; Hawks, Steven A; Xie, Chenlu; Cui, Fan; Alivisatos, A Paul; Limmer, David T; Yang, Peidong

2018-03-01

Smart photovoltaic windows represent a promising green technology featuring tunable transparency and electrical power generation under external stimuli to control the light transmission and manage the solar energy. Here, we demonstrate a thermochromic solar cell for smart photovoltaic window applications utilizing the structural phase transitions in inorganic halide perovskite caesium lead iodide/bromide. The solar cells undergo thermally-driven, moisture-mediated reversible transitions between a transparent non-perovskite phase (81.7% visible transparency) with low power output and a deeply coloured perovskite phase (35.4% visible transparency) with high power output. The inorganic perovskites exhibit tunable colours and transparencies, a peak device efficiency above 7%, and a phase transition temperature as low as 105 °C. We demonstrate excellent device stability over repeated phase transition cycles without colour fade or performance degradation. The photovoltaic windows showing both photoactivity and thermochromic features represent key stepping-stones for integration with buildings, automobiles, information displays, and potentially many other technologies.

Thermochromic halide perovskite solar cells

NASA Astrophysics Data System (ADS)

Lin, Jia; Lai, Minliang; Dou, Letian; Kley, Christopher S.; Chen, Hong; Peng, Fei; Sun, Junliang; Lu, Dylan; Hawks, Steven A.; Xie, Chenlu; Cui, Fan; Alivisatos, A. Paul; Limmer, David T.; Yang, Peidong

2018-03-01

Smart photovoltaic windows represent a promising green technology featuring tunable transparency and electrical power generation under external stimuli to control the light transmission and manage the solar energy. Here, we demonstrate a thermochromic solar cell for smart photovoltaic window applications utilizing the structural phase transitions in inorganic halide perovskite caesium lead iodide/bromide. The solar cells undergo thermally-driven, moisture-mediated reversible transitions between a transparent non-perovskite phase (81.7% visible transparency) with low power output and a deeply coloured perovskite phase (35.4% visible transparency) with high power output. The inorganic perovskites exhibit tunable colours and transparencies, a peak device efficiency above 7%, and a phase transition temperature as low as 105 °C. We demonstrate excellent device stability over repeated phase transition cycles without colour fade or performance degradation. The photovoltaic windows showing both photoactivity and thermochromic features represent key stepping-stones for integration with buildings, automobiles, information displays, and potentially many other technologies.

Perivascular epithelioid cell tumor (PEComa) with TFE3 gene rearrangement: clinicopathological, immunohistochemical, and molecular features.

PubMed

Shen, Qin; Rao, Qiu; Xia, Qiu-Yuan; Yu, Bo; Shi, Qun-Li; Zhang, Ru-Song; Zhou, Xiao-Jun

2014-11-01

Perivascular epithelioid cell tumors (PEComas) have been increasingly associated with gene rearrangement of the transcription factor E3 (TFE3). We present three cases of PEComa with a TFE3 gene abnormality detected by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Their clinical features, pathological morphology, and prognosis were investigated. Histologically, the tumors in these three cases showed predominantly epithelioid cells arranged in nests or sheets separated by a delicate vascular network, within two of the three cases nuclear atypia, mitotic figures, and necrosis. All three cases showed strong TFE3 and cathepsin K immunoreactivity and weak to strong reactivity for HMB45. One case of PEComa with TFE3 gene fusion exhibited a benign course. The other two cases of PEComa with both TFE3 translocation and X-chromosome polysomy were histologically malignant and showed aggressive growth. In summary, unusual cases of PEComa with TFE3 gene rearrangement might present malignant histological features and aggressive clinical behavior. Our results add cases to the literature and describe an association of polysomy with aggressive behavior.

Structure-activity models of oral clearance, cytotoxicity, and LD50: a screen for promising anticancer compounds

PubMed Central

Boik, John C; Newman, Robert A

2008-01-01

Background Quantitative structure-activity relationship (QSAR) models have become popular tools to help identify promising lead compounds in anticancer drug development. Few QSAR studies have investigated multitask learning, however. Multitask learning is an approach that allows distinct but related data sets to be used in training. In this paper, a suite of three QSAR models is developed to identify compounds that are likely to (a) exhibit cytotoxic behavior against cancer cells, (b) exhibit high rat LD50 values (low systemic toxicity), and (c) exhibit low to modest human oral clearance (favorable pharmacokinetic characteristics). Models were constructed using Kernel Multitask Latent Analysis (KMLA), an approach that can effectively handle a large number of correlated data features, nonlinear relationships between features and responses, and multitask learning. Multitask learning is particularly useful when the number of available training records is small relative to the number of features, as was the case with the oral clearance data. Results Multitask learning modestly but significantly improved the classification precision for the oral clearance model. For the cytotoxicity model, which was constructed using a large number of records, multitask learning did not affect precision but did reduce computation time. The models developed here were used to predict activities for 115,000 natural compounds. Hundreds of natural compounds, particularly in the anthraquinone and flavonoids groups, were predicted to be cytotoxic, have high LD50 values, and have low to moderate oral clearance. Conclusion Multitask learning can be useful in some QSAR models. A suite of QSAR models was constructed and used to screen a large drug library for compounds likely to be cytotoxic to multiple cancer cell lines in vitro, have low systemic toxicity in rats, and have favorable pharmacokinetic properties in humans. PMID:18554402

Structure-activity models of oral clearance, cytotoxicity, and LD50: a screen for promising anticancer compounds.

PubMed

Boik, John C; Newman, Robert A

2008-06-13

Quantitative structure-activity relationship (QSAR) models have become popular tools to help identify promising lead compounds in anticancer drug development. Few QSAR studies have investigated multitask learning, however. Multitask learning is an approach that allows distinct but related data sets to be used in training. In this paper, a suite of three QSAR models is developed to identify compounds that are likely to (a) exhibit cytotoxic behavior against cancer cells, (b) exhibit high rat LD50 values (low systemic toxicity), and (c) exhibit low to modest human oral clearance (favorable pharmacokinetic characteristics). Models were constructed using Kernel Multitask Latent Analysis (KMLA), an approach that can effectively handle a large number of correlated data features, nonlinear relationships between features and responses, and multitask learning. Multitask learning is particularly useful when the number of available training records is small relative to the number of features, as was the case with the oral clearance data. Multitask learning modestly but significantly improved the classification precision for the oral clearance model. For the cytotoxicity model, which was constructed using a large number of records, multitask learning did not affect precision but did reduce computation time. The models developed here were used to predict activities for 115,000 natural compounds. Hundreds of natural compounds, particularly in the anthraquinone and flavonoids groups, were predicted to be cytotoxic, have high LD50 values, and have low to moderate oral clearance. Multitask learning can be useful in some QSAR models. A suite of QSAR models was constructed and used to screen a large drug library for compounds likely to be cytotoxic to multiple cancer cell lines in vitro, have low systemic toxicity in rats, and have favorable pharmacokinetic properties in humans.

Zipf's Law in Gene Expression

NASA Astrophysics Data System (ADS)

Furusawa, Chikara; Kaneko, Kunihiko

2003-02-01

Using data from gene expression databases on various organisms and tissues, including yeast, nematodes, human normal and cancer tissues, and embryonic stem cells, we found that the abundances of expressed genes exhibit a power-law distribution with an exponent close to -1; i.e., they obey Zipf’s law. Furthermore, by simulations of a simple model with an intracellular reaction network, we found that Zipf’s law of chemical abundance is a universal feature of cells where such a network optimizes the efficiency and faithfulness of self-reproduction. These findings provide novel insights into the nature of the organization of reaction dynamics in living cells.

Effect of electrode sub-micron surface feature size on current generation of Shewanella oneidensis in microbial fuel cells

NASA Astrophysics Data System (ADS)

Ye, Zhou; Ellis, Michael W.; Nain, Amrinder S.; Behkam, Bahareh

2017-04-01

Microbial fuel cells (MFCs) are envisioned to serve as compact and sustainable sources of energy; however, low current and power density have hindered their widespread use. Introduction of 3D micro/nanostructures on the MFC anode is known to improve its performance by increasing the surface area available for bacteria attachment; however, the role of the feature size remains poorly understood. To delineate the role of feature size from the ensuing surface area increase, nanostructures with feature heights of 115 nm and 300 nm, both at a height to width aspect ratio of 0.3, are fabricated in a grid pattern on glassy carbon electrodes (GCEs). Areal current densities and bacteria attachment densities of the patterned and unpatterned GCEs are compared using Shewanella oneidensis Δbfe in a three-electrode bioreactor. The 115 nm features elicit a remarkable 40% increase in current density and a 78% increase in bacterial attachment density, whereas the GCE with 300 nm pattern does not exhibit significant change in current density or bacterial attachment density. The current density dependency on feature size is maintained over the entire 160 h experiment. Thus, optimally sized surface features have a substantial effect on current production that is independent of their effect on surface area.

Evidence for label-retaining tumour-initiating cells in human glioblastoma

PubMed Central

Deleyrolle, Loic P.; Harding, Angus; Cato, Kathleen; Siebzehnrubl, Florian A.; Rahman, Maryam; Azari, Hassan; Olson, Sarah; Gabrielli, Brian; Osborne, Geoffrey; Vescovi, Angelo

2011-01-01

Individual tumour cells display diverse functional behaviours in terms of proliferation rate, cell–cell interactions, metastatic potential and sensitivity to therapy. Moreover, sequencing studies have demonstrated surprising levels of genetic diversity between individual patient tumours of the same type. Tumour heterogeneity presents a significant therapeutic challenge as diverse cell types within a tumour can respond differently to therapies, and inter-patient heterogeneity may prevent the development of general treatments for cancer. One strategy that may help overcome tumour heterogeneity is the identification of tumour sub-populations that drive specific disease pathologies for the development of therapies targeting these clinically relevant sub-populations. Here, we have identified a dye-retaining brain tumour population that displays all the hallmarks of a tumour-initiating sub-population. Using a limiting dilution transplantation assay in immunocompromised mice, label-retaining brain tumour cells display elevated tumour-initiation properties relative to the bulk population. Importantly, tumours generated from these label-retaining cells exhibit all the pathological features of the primary disease. Together, these findings confirm dye-retaining brain tumour cells exhibit tumour-initiation ability and are therefore viable targets for the development of therapeutics targeting this sub-population. PMID:21515906

Fluid phase biopsy for detection and characterization of circulating endothelial cells in myocardial infarction

NASA Astrophysics Data System (ADS)

Bethel, Kelly; Luttgen, Madelyn S.; Damani, Samir; Kolatkar, Anand; Lamy, Rachelle; Sabouri-Ghomi, Mohsen; Topol, Sarah; Topol, Eric J.; Kuhn, Peter

2014-02-01

Elevated levels of circulating endothelial cells (CECs) occur in response to various pathological conditions including myocardial infarction (MI). Here, we adapted a fluid phase biopsy technology platform that successfully detects circulating tumor cells in the blood of cancer patients (HD-CTC assay), to create a high-definition circulating endothelial cell (HD-CEC) assay for the detection and characterization of CECs. Peripheral blood samples were collected from 79 MI patients, 25 healthy controls and six patients undergoing vascular surgery (VS). CECs were defined by positive staining for DAPI, CD146 and von Willebrand Factor and negative staining for CD45. In addition, CECs exhibited distinct morphological features that enable differentiation from surrounding white blood cells. CECs were found both as individual cells and as aggregates. CEC numbers were higher in MI patients compared with healthy controls. VS patients had lower CEC counts when compared with MI patients but were not different from healthy controls. Both HD-CEC and CellSearch® assays could discriminate MI patients from healthy controls with comparable accuracy but the HD-CEC assay exhibited higher specificity while maintaining high sensitivity. Our HD-CEC assay may be used as a robust diagnostic biomarker in MI patients.

Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

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

Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva

2011-10-28

Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth ofmore » undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.« less

Isogambogenic acid induces apoptosis-independent autophagic cell death in human non-small-cell lung carcinoma cells.

PubMed

Yang, Jianhong; Zhou, Yongzhao; Cheng, Xia; Fan, Yi; He, Shichao; Li, Shucai; Ye, Haoyu; Xie, Caifeng; Wu, Wenshuang; Li, Chunyan; Pei, Heying; Li, Luyuan; Wei, Zhe; Peng, Aihua; Wei, Yuquan; Li, Weimin; Chen, Lijuan

2015-01-09

To overcome drug resistance caused by apoptosis deficiency in patients with non-small cell lung carcinoma (NSCLC), there is a need to identify other means of triggering apoptosis-independent cancer cell death. We are the first to report that isogambogenic acid (iso-GNA) can induce apoptosis-independent autophagic cell death in human NSCLC cells. Several features of the iso-GNA-treated NSCLC cells indicated that iso-GNA induced autophagic cell death. First, there was no evidence of apoptosis or cleaved caspase 3 accumulation and activation. Second, iso-GNA treatment induced the formation of autophagic vacuoles, increased LC3 conversion, caused the appearance of autophagosomes and increased the expression of autophagy-related proteins. These findings provide evidence that iso-GNA induces autophagy in NSCLC cells. Third, iso-GNA-induced cell death was inhibited by autophagic inhibitors or by selective ablation of Atg7 and Beclin 1 genes. Furthermore, the mTOR inhibitor rapamycin increased iso-GNA-induced cell death by enhancing autophagy. Finally, a xenograft model provided additional evidence that iso-GNA exhibited anticancer effect through inducing autophagy-dependent cell death in NSCLC cells. Taken together, our results demonstrated that iso-GNA exhibited an anticancer effect by inducing autophagy-dependent cell death in NSCLC cells, which may be an effective chemotherapeutic agent that can be used against NSCLC in a clinical setting.

Isogambogenic acid induces apoptosis-independent autophagic cell death in human non-small-cell lung carcinoma cells

PubMed Central

Yang, Jianhong; Zhou, Yongzhao; Cheng, Xia; Fan, Yi; He, Shichao; Li, Shucai; Ye, Haoyu; Xie, Caifeng; Wu, Wenshuang; Li, Chunyan; Pei, Heying; Li, Luyuan; Wei, Zhe; Peng, Aihua; Wei, Yuquan; Li, Weimin; Chen, Lijuan

2015-01-01

To overcome drug resistance caused by apoptosis deficiency in patients with non-small cell lung carcinoma (NSCLC), there is a need to identify other means of triggering apoptosis-independent cancer cell death. We are the first to report that isogambogenic acid (iso-GNA) can induce apoptosis-independent autophagic cell death in human NSCLC cells. Several features of the iso-GNA-treated NSCLC cells indicated that iso-GNA induced autophagic cell death. First, there was no evidence of apoptosis or cleaved caspase 3 accumulation and activation. Second, iso-GNA treatment induced the formation of autophagic vacuoles, increased LC3 conversion, caused the appearance of autophagosomes and increased the expression of autophagy-related proteins. These findings provide evidence that iso-GNA induces autophagy in NSCLC cells. Third, iso-GNA-induced cell death was inhibited by autophagic inhibitors or by selective ablation of Atg7 and Beclin 1 genes. Furthermore, the mTOR inhibitor rapamycin increased iso-GNA-induced cell death by enhancing autophagy. Finally, a xenograft model provided additional evidence that iso-GNA exhibited anticancer effect through inducing autophagy-dependent cell death in NSCLC cells. Taken together, our results demonstrated that iso-GNA exhibited an anticancer effect by inducing autophagy-dependent cell death in NSCLC cells, which may be an effective chemotherapeutic agent that can be used against NSCLC in a clinical setting. PMID:25571970

A scanning electron microscopic study of 34 cases of acute granulocytic, myelomonocytic, monoblastic and histiocytic leukemia.

PubMed

Polliack, A; McKenzie, S; Gee, T; Lampen, N; de Harven, E; Clarkson, B D

1975-09-01

This report describes the surface architecture of leukemic cells, as seen by scanning electron microscopy in 34 patients with acute nonlymphoblastic leukemia. Six patients with myeloblastic, 4 with promyelocytic, 10 with myelomonocytic, 8 with monocytic, 4 with histiocytic and 2 with undifferentiated leukemia were studied. Under the scanning electron microscope most leukemia histiocytes and monocytes appeared similar and were characterized by the presence of large, well developed broad-based ruffled membranes or prominent raised ridge-like profiles, resembling ithis respect normal monocytes. Most cells from patients with acute promyelocytic or myeloblastic leukemia exhibited narrower ridge-like profiles whereas some showed ruffles or microvilli. Patients with myelomonocytic leukemia showed mixed populations of cells with ridge-like profiles and ruffled membranes whereas cells from two patients with undifferentiated leukemia had smooth surfaces, similar to those encountered in cells from patients with acute lymphoblastic leukemia. It appears that nonlymphoblastic and lymphoblastic leukemia cells (particularly histiocytes and monocytes) can frequently be distinquished on the basis of their surface architecture. The surface features of leukemic histiocytes and monocytes are similar, suggesting that they may belong to the same cell series. The monocytes seem to have characteristic surface features recognizable with the scanning electron microscope and differ from most cells from patients with acute granulocytic leukemia. Although overlap of surface features and misidentification can occur, scanning electron microscopy is a useful adjunct to other modes of microscopy in the study and diagnosis of acute leukemia.

Immunohistochemical evaluation of canine peripheral nerve sheath tumors and other soft tissue sarcomas.

PubMed

Chijiwa, K; Uchida, K; Tateyama, S

2004-07-01

Seventeen cases of canine peripheral nerve sheath tumors (PNSTs), 11 malignant PNSTs (MPNSTs), and six benign PNSTs (BPNSTs) were examined. The prognosis in five of six dogs with BPNSTs was excellent, whereas all dogs with MPNSTs died within 2 years after the last surgical resection. One BPNST formed a recurrent mass with features of a MPNST. Histopathologically, the predominant tumor cell of MPNSTs was either spindle or round in shape with epithelioid characteristics. Other atypical cells had abundant granular cytoplasm or were multinucleated giant cells with periodic acid-Schiff-positive cytoplasmic globules. Furthermore, two MPNSTs contained cartilaginous and osseous metaplasia. On the contrary, most BPNSTs exhibited typical features of schwannoma or neurofibroma, whereas two BPNSTs had atypical morphology. One BPNST consisted of epithelioid cell proliferation with some tumor cells revealing nuclear atypia. Immunohistochemically, the expression of vimentin (100%), S-100 (73%), nerve growth factor receptor (NGFR, 64%), and myoglobin (64%) was commonly found in MPNSTs. The two BPNSTs with atypical histologic appearances were positive for vimentin, S-100, NGFR, and neuron-specific enolase, and one of these had moderate immunoreactivity for cytokeratin. Most BPNSTs were positive for glial fibrillary acidic protein, as well as S-100 and NGFR. Although most rhabdomyosarcomas (RMSs) and canine hemangiopericytomas (CHPs) also showed focal immunoreactivity for S-100, most RMSs were intensely positive for myoglobin and negative for NGFR. Most CHPs (80%) exhibited focal alpha-smooth muscle actin (alpha-SMA) expression, whereas all PNSTs were negative. These results indicate that immunohistochemistry for NGFR and alpha-SMA might be useful for differentiating canine PNSTs from RMSs or CHPs, respectively.

Validating continuous digital light processing (cDLP) additive manufacturing accuracy and tissue engineering utility of a dye-initiator package.

PubMed

Wallace, Jonathan; Wang, Martha O; Thompson, Paul; Busso, Mallory; Belle, Vaijayantee; Mammoser, Nicole; Kim, Kyobum; Fisher, John P; Siblani, Ali; Xu, Yueshuo; Welter, Jean F; Lennon, Donald P; Sun, Jiayang; Caplan, Arnold I; Dean, David

2014-03-01

This study tested the accuracy of tissue engineering scaffold rendering via the continuous digital light processing (cDLP) light-based additive manufacturing technology. High accuracy (i.e., <50 µm) allows the designed performance of features relevant to three scale spaces: cell-scaffold, scaffold-tissue, and tissue-organ interactions. The biodegradable polymer poly (propylene fumarate) was used to render highly accurate scaffolds through the use of a dye-initiator package, TiO2 and bis (2,4,6-trimethylbenzoyl)phenylphosphine oxide. This dye-initiator package facilitates high accuracy in the Z dimension. Linear, round, and right-angle features were measured to gauge accuracy. Most features showed accuracies between 5.4-15% of the design. However, one feature, an 800 µm diameter circular pore, exhibited a 35.7% average reduction of patency. Light scattered in the x, y directions by the dye may have reduced this feature's accuracy. Our new fine-grained understanding of accuracy could be used to make further improvements by including corrections in the scaffold design software. Successful cell attachment occurred with both canine and human mesenchymal stem cells (MSCs). Highly accurate cDLP scaffold rendering is critical to the design of scaffolds that both guide bone regeneration and that fully resorb. Scaffold resorption must occur for regenerated bone to be remodeled and, thereby, achieve optimal strength.

Deficient mitochondrial biogenesis in IL-2 activated NK cells correlates with impaired PGC1-α upregulation in elderly humans.

PubMed

Miranda, Dante; Jara, Claudia; Mejias, Sophia; Ahumada, Viviana; Cortez-San Martin, Marcelo; Ibañez, Jorge; Hirsch, Sandra; Montoya, Margarita

2018-05-18

Immunosenescence has been described as age-associated changes in the immune function which are thought to be responsible for the increased morbidity with age. Human Natural Killer (NK) cells are a specialized heterogeneous subpopulation of lymphocytes involved in immune defense against tumor and microbial diseases. Interestingly, aging-related NK cell dysfunction is associated with features of aging such as tumor incidence, reduced vaccination efficacy, and short survival due to infection. It is known that NK cell effector functions are critically dependent on cytokines and metabolic activity. Our aim was to determine whether there is a difference in purified human NK cell function in response to high concentration of IL-2 between young and elder donors. Here, we report that the stimulation of human NK cells with IL-2 (2000 U/mL) enhance NK cell cytotoxic activity from both young and elderly donors. However, while NK cells from young people responded to IL-2 signaling by increasing mitochondrial mass and mitochondrial membrane potential, no increase in these mitochondrial functional parameters was seen in purified NK cells from elderly subjects. Moreover, as purified NK cells from the young exhibited an almost three-fold increase in PGC-1α expression after IL-2 (2000 U/mL) stimulation, PGC-1α expression was inhibited in purified NK cells from elders. Furthermore, this response upon PGC-1α expression after IL-2 stimulation promoted an increase in ROS production in NK cells from elderly humans, while no increase in ROS production was observed in NK cells of young donors. Our data show that IL-2 stimulates NK cell effector function through a signaling pathway which involves a PGC-1α-dependent mitochondrial function in young NK cells, however it seems that NK cells from older donors exhibit an altered IL-2 signaling which affects mitochondrial function associated with an increased production of ROS which could represent a feature of NK cell senescence. Copyright © 2018 Elsevier Inc. All rights reserved.

Aging-associated inflammation promotes selection for adaptive oncogenic events in B cell progenitors.

PubMed

Henry, Curtis J; Casás-Selves, Matias; Kim, Jihye; Zaberezhnyy, Vadym; Aghili, Leila; Daniel, Ashley E; Jimenez, Linda; Azam, Tania; McNamee, Eoin N; Clambey, Eric T; Klawitter, Jelena; Serkova, Natalie J; Tan, Aik Choon; Dinarello, Charles A; DeGregori, James

2015-12-01

The incidence of cancer is higher in the elderly; however, many of the underlying mechanisms for this association remain unexplored. Here, we have shown that B cell progenitors in old mice exhibit marked signaling, gene expression, and metabolic defects. Moreover, B cell progenitors that developed from hematopoietic stem cells (HSCs) transferred from young mice into aged animals exhibited similar fitness defects. We further demonstrated that ectopic expression of the oncogenes BCR-ABL, NRAS(V12), or Myc restored B cell progenitor fitness, leading to selection for oncogenically initiated cells and leukemogenesis specifically in the context of an aged hematopoietic system. Aging was associated with increased inflammation in the BM microenvironment, and induction of inflammation in young mice phenocopied aging-associated B lymphopoiesis. Conversely, a reduction of inflammation in aged mice via transgenic expression of α-1-antitrypsin or IL-37 preserved the function of B cell progenitors and prevented NRAS(V12)-mediated oncogenesis. We conclude that chronic inflammatory microenvironments in old age lead to reductions in the fitness of B cell progenitor populations. This reduced progenitor pool fitness engenders selection for cells harboring oncogenic mutations, in part due to their ability to correct aging-associated functional defects. Thus, modulation of inflammation--a common feature of aging--has the potential to limit aging-associated oncogenesis.

Overexpression of interleukin-6 and -8, cell growth inhibition and morphological changes in 2-hydroxyethyl methacrylate-treated human dental pulp mesenchymal stem cells.

PubMed

Trubiani, O; Cataldi, A; De Angelis, F; D'Arcangelo, C; Caputi, S

2012-01-01

To evaluate morphological features, cell growth and interleukin-6 (IL-6) and interleukin-8 (IL-8) secretion in expanded ex vivo human dental pulp mesenchymal stem cells (DP-MSCs) after exposure to 2-hydroxyethyl methacrylate (HEMA).   Dental pulp mesenchymal stem cells were derived from the dental pulps of 10 young donors. After in vitro isolation, DP-MSCs were treated with 3 and 5 mmol L(-1) HEMA, and after 24, 48 and 72 h of incubation, their morphological features, cell growth, IL-6 and IL-8 secretion were analysed. Differences in the cell growth and in the interleukin secretion were analysed for statistical significance with two-way anova tests and the Holm-Sidak method for multiple comparisons.   Dental pulp mesenchymal stem cells revealed a decrease in cell growth with both treatments (P < 0.05), more evident at 5 mmol L(-1) . Microscopic analysis displayed extensive cytotoxic effects in treated cells, which lost their fibroblastoid features and became retracted, even roundish, with a large number of granules. An up-regulation of IL-6 and IL-8 in treated cells cytokines was evident (P < 0.05).   2-Hydroxyethyl methacrylate exhibited cytotoxicity, inhibited cell growth and induced morphological changes in cultured DP-MSCs. Moreover, in treated samples, an up-regulation of soluble mediators of inflammation such as IL-6 and IL-8 cytokines was found. The direct application of HEMA potentially induces an inflammation process that could be the starting point for toxic response and cell damage in DP-MSCs. © 2011 International Endodontic Journal.

Nonstimulated human uncommitted mesenchymal stem cells express cell markers of mesenchymal and neural lineages.

PubMed

Minguell, José J; Fierro, Fernando A; Epuñan, María J; Erices, Alejandro A; Sierralta, Walter D

2005-08-01

Ex vivo cultures of human bone marrow-derived mesenchymal stem cells (MSCs) contain subsets of progenitors exhibiting dissimilar properties. One of these subsets comprises uncommitted progenitors displaying distinctive features, such as morphology, a quiescent condition, growth factor production, and restricted tissue biodistribution after transplantation. In this study, we assessed the competence of these cells to express, in the absence of differentiation stimuli, markers of mesoderm and ectodermic (neural) cell lineages. Fluorescence microscopy analysis showed a unique pattern of expression of osteogenic, chondrogenic, muscle, and neural markers. The depicted "molecular signature" of these early uncommitted progenitors, in the absence of differentiation stimuli, is consistent with their multipotentiality and plasticity as suggested by several in vitro and in vivo studies.

Network Characteristics of Collective Chemosensing

NASA Astrophysics Data System (ADS)

Sun, Bo; Duclos, Guillaume; Stone, Howard A.

2013-04-01

The collective chemosensing of nonexcitable mammalian cells involves a biochemical network that features gap junction communications and heterogeneous single cell activities. To understand the integrated multicellular chemosensing, we study the calcium dynamics of micropatterned fibroblast cell colonies in response to adenosine triphosphate (ATP) stimulation. We find that the cross-correlation function between the responses of individual cells decays with topological distance as a power law for large colonies and much faster for smaller colonies. Furthermore, the strongly correlated cell pairs tend to form clusters and are more likely to exceed the percolation threshold. At a given topological distance, the cross-correlations exhibit characteristics of Poisson distributions, which allows us to estimate the unitary conductance of a single gap junction which is in good agreement with direct experimental measurements.

Cutaneous Malignant Melanoma With Rhabdoid Morphology and Smooth Muscle Differentiation: A Challenging Histopathologic Diagnosis.

PubMed

Prieto-Torres, Lucía; Alegría-Landa, Victoria; Llanos, Concepción; Córdoba, Alicia; Kutzner, Heinz; Requena, Luis

2017-05-01

Divergent differentiation or metaplastic change is a rare feature exhibited occasionally in malignant melanoma (MM), which is characterized by the development of morphologically, immunochemically, and/or ultrastructurally nonmelanocytic cells within the tumor. Smooth muscle differentiation in MM is an exceedingly rare phenomenon reported only in a few cases in the literature. We report the case of a 69-year-old woman who presented with a pure dermal amelanotic MM with smooth muscle cell differentiation and an area of rhabdoid morphology, which made the accurate histopathologic diagnostic of MM challenging.

Dedifferentiated Liposarcoma With Epithelioid/Epithelial Features.

PubMed

Makise, Naohiro; Yoshida, Akihiko; Komiyama, Motokiyo; Nakatani, Fumihiko; Yonemori, Kan; Kawai, Akira; Fukayama, Masashi; Hiraoka, Nobuyoshi

2017-11-01

Dedifferentiated liposarcoma (DDLPS) demonstrates a variety of growth patterns, and their histologic resemblance to other spindle cell mesenchymal tumors has been widely recognized. However, epithelioid morphology in DDLPS has only rarely been documented. Here, we report 6 cases of DDLPS with striking epithelioid/epithelial features. The patients were 5 men and 1 woman with a median age of 61 years. All tumors were located in the internal trunk. During follow-up of 1 to 41 months, local recurrence, distant metastases, and tumor-related death occurred in 4, 2, and 4 patients, respectively. Beside well-differentiated liposarcoma component and conventional high-grade spindle cell morphology, all tumors focally exhibited growth comprising small or large epithelioid cells in diffuse or sheet-like proliferation. Rhabdoid cells were present in 2 cases. All 5 tumors tested harbored MDM2 amplification. Cytokeratin and/or epithelial membrane antigen were at least focally positive in all 5 tumors tested. One case contained a small focus of novel heterologous epithelial differentiation with acinar structures, wherein cytokeratin, MOC31, and claudin-4 were diffusely expressed and H3K27me3 expression was lost. DDLPS with epithelioid/epithelial features may lead to misdiagnosis of carcinoma or mesothelioma, and their diagnosis should be based on correlation with clinicopathologic and molecular findings. The epithelioid morphology in DDLPS may suggest an aggressive behavior based on this small series. In addition, we document 2 cases of MDM2-amplified undifferentiated neoplasm with epithelioid features in the internal trunk that lacked association with well-differentiated liposarcoma histology and showed rapid clinical course. Whether these latter tumors belong to DDLPS with epithelioid features requires further study.

Synthesis, characterization, and anticancer activity of new quinazoline derivatives against MCF-7 cells.

PubMed

Faraj, Fadhil Lafta; Zahedifard, Maryam; Paydar, Mohammadjavad; Looi, Chung Yeng; Abdul Majid, Nazia; Ali, Hapipah Mohd; Ahmad, Noraini; Gwaram, Nura Suleiman; Abdulla, Mahmood Ameen

2014-01-01

Two new synthesized and characterized quinazoline Schiff bases 1 and 2 were investigated for anticancer activity against MCF-7 human breast cancer cell line. Compounds 1 and 2 demonstrated a remarkable antiproliferative effect, with an IC50 value of 6.246×10(-6) mol/L and 5.910×10(-6) mol/L, respectively, after 72 hours of treatment. Most apoptosis morphological features in treated MCF-7 cells were observed by AO/PI staining. The results of cell cycle analysis indicate that compounds did not induce S and M phase arrest in cell after 24 hours of treatment. Furthermore, MCF-7 cells treated with 1 and 2 subjected to apoptosis death, as exhibited by perturbation of mitochondrial membrane potential and cytochrome c release as well as increase in ROS formation. We also found activation of caspases-3/7, -8, and -9 in compounds 1 and 2. Moreover, inhibition of NF-κB translocation in MCF-7 cells treated by compound 1 significantly exhibited the association of extrinsic apoptosis pathway. Acute toxicity results demonstrated the nontoxic nature of the compounds in mice. Our results showed significant activity towards MCF-7 cells via either intrinsic or extrinsic mitochondrial pathway and are potential candidate for further in vivo and clinical breast cancer studies.

Synthesis, Characterization, and Anticancer Activity of New Quinazoline Derivatives against MCF-7 Cells

PubMed Central

Faraj, Fadhil Lafta; Zahedifard, Maryam; Paydar, Mohammadjavad; Looi, Chung Yeng; Abdul Majid, Nazia; Ali, Hapipah Mohd; Ahmad, Noraini; Gwaram, Nura Suleiman; Abdulla, Mahmood Ameen

2014-01-01

Two new synthesized and characterized quinazoline Schiff bases 1 and 2 were investigated for anticancer activity against MCF-7 human breast cancer cell line. Compounds 1 and 2 demonstrated a remarkable antiproliferative effect, with an IC50 value of 6.246 × 10−6 mol/L and 5.910 × 10−6 mol/L, respectively, after 72 hours of treatment. Most apoptosis morphological features in treated MCF-7 cells were observed by AO/PI staining. The results of cell cycle analysis indicate that compounds did not induce S and M phase arrest in cell after 24 hours of treatment. Furthermore, MCF-7 cells treated with 1 and 2 subjected to apoptosis death, as exhibited by perturbation of mitochondrial membrane potential and cytochrome c release as well as increase in ROS formation. We also found activation of caspases-3/7, -8, and -9 in compounds 1 and 2. Moreover, inhibition of NF-κB translocation in MCF-7 cells treated by compound 1 significantly exhibited the association of extrinsic apoptosis pathway. Acute toxicity results demonstrated the nontoxic nature of the compounds in mice. Our results showed significant activity towards MCF-7 cells via either intrinsic or extrinsic mitochondrial pathway and are potential candidate for further in vivo and clinical breast cancer studies. PMID:25548779

Physical and biophysical assessment of highly fluorescent, magnetic quantum dots of a wurtzite-phase manganese selenide system

NASA Astrophysics Data System (ADS)

Sarma, Runjun; Das, Queen; Hussain, Anowar; Ramteke, Anand; Choudhury, Amarjyoti; Mohanta, Dambarudhar

2014-07-01

Combining fluorescence and magnetic features in a non-iron based, select type of quantum dots (QDs) can have immense value in cellular imaging, tagging and other nano-bio interface applications, including targeted drug delivery. Herein, we report on the colloidal synthesis and physical and biophysical assessment of wurtzite-type manganese selenide (MnSe) QDs in cell culture media. Aiming to provide a suitable colloidal system of biological relevance, different concentrations of reactants and ligands (e.g., thioglycolic acid, TGA) have been considered. The average size of the QDs is ˜7 nm, which exhibited a quantum yield of ˜75% as compared to rhodamine 6 G dye®. As revealed from time-resolved photoluminescence (TR-PL) response, the near band edge emission followed a bi-exponential decay feature with characteristic times of ˜0.64 ns and 3.04 ns. At room temperature, the QDs were found to exhibit paramagnetic features with coercivity and remanence impelled by TGA concentrations. With BSA as a dispersing agent, the QDs showed an improved optical stability in Dulbecco’s Modified Eagle Media® (DMEM) and Minimum Essential Media® (MEM), as compared to the Roswell Park Memorial Institute® (RPMI-1640) media. Finally, the cell viability of lymphocytes was found to be strongly influenced by the concentration of MnSe QDs, and had a safe limit upto 0.5 μM. With BSA inclusion in cell media, the cellular uptake of MnSe QDs was observed to be more prominent, as revealed from fluorescence imaging. The fabrication of water soluble, nontoxic MnSe QDs would open up an alternative strategy in nanobiotechnology, while preserving their luminescent and magnetic properties intact.

p53 downregulates the Fanconi anaemia DNA repair pathway

PubMed Central

Jaber, Sara; Toufektchan, Eléonore; Lejour, Vincent; Bardot, Boris; Toledo, Franck

2016-01-01

Germline mutations affecting telomere maintenance or DNA repair may, respectively, cause dyskeratosis congenita or Fanconi anaemia, two clinically related bone marrow failure syndromes. Mice expressing p53Δ31, a mutant p53 lacking the C terminus, model dyskeratosis congenita. Accordingly, the increased p53 activity in p53Δ31/Δ31 fibroblasts correlated with a decreased expression of 4 genes implicated in telomere syndromes. Here we show that these cells exhibit decreased mRNA levels for additional genes contributing to telomere metabolism, but also, surprisingly, for 12 genes mutated in Fanconi anaemia. Furthermore, p53Δ31/Δ31 fibroblasts exhibit a reduced capacity to repair DNA interstrand crosslinks, a typical feature of Fanconi anaemia cells. Importantly, the p53-dependent downregulation of Fanc genes is largely conserved in human cells. Defective DNA repair is known to activate p53, but our results indicate that, conversely, an increased p53 activity may attenuate the Fanconi anaemia DNA repair pathway, defining a positive regulatory feedback loop. PMID:27033104

p53 downregulates the Fanconi anaemia DNA repair pathway.

PubMed

Jaber, Sara; Toufektchan, Eléonore; Lejour, Vincent; Bardot, Boris; Toledo, Franck

2016-04-01

Germline mutations affecting telomere maintenance or DNA repair may, respectively, cause dyskeratosis congenita or Fanconi anaemia, two clinically related bone marrow failure syndromes. Mice expressing p53(Δ31), a mutant p53 lacking the C terminus, model dyskeratosis congenita. Accordingly, the increased p53 activity in p53(Δ31/Δ31) fibroblasts correlated with a decreased expression of 4 genes implicated in telomere syndromes. Here we show that these cells exhibit decreased mRNA levels for additional genes contributing to telomere metabolism, but also, surprisingly, for 12 genes mutated in Fanconi anaemia. Furthermore, p53(Δ31/Δ31) fibroblasts exhibit a reduced capacity to repair DNA interstrand crosslinks, a typical feature of Fanconi anaemia cells. Importantly, the p53-dependent downregulation of Fanc genes is largely conserved in human cells. Defective DNA repair is known to activate p53, but our results indicate that, conversely, an increased p53 activity may attenuate the Fanconi anaemia DNA repair pathway, defining a positive regulatory feedback loop.

The cancer theory of pulmonary arterial hypertension

PubMed Central

Boucherat, Olivier; Vitry, Geraldine; Trinh, Isabelle; Paulin, Roxane; Provencher, Steeve; Bonnet, Sebastien

2017-01-01

Pulmonary arterial hypertension (PAH) remains a mysterious killer that, like cancer, is characterized by tremendous complexity. PAH development occurs under sustained and persistent environmental stress, such as inflammation, shear stress, pseudo-hypoxia, and more. After inducing an initial death of the endothelial cells, these environmental stresses contribute with time to the development of hyper-proliferative and apoptotic resistant clone of cells including pulmonary artery smooth muscle cells, fibroblasts, and even pulmonary artery endothelial cells allowing vascular remodeling and PAH development. Molecularly, these cells exhibit many features common to cancer cells offering the opportunity to exploit therapeutic strategies used in cancer to treat PAH. In this review, we outline the signaling pathways and mechanisms described in cancer that drive PAH cells’ survival and proliferation and discuss the therapeutic potential of antineoplastic drugs in PAH. PMID:28597757

Neurogenic and cardiomyogenic differentiation of mesenchymal stem cells isolated from minipig bone marrow.

PubMed

Kumar, B Mohana; Maeng, Geun-Ho; Lee, Yeon-Mi; Kim, Tae-Ho; Lee, Jeong-Hyeon; Jeon, Byeong-Gyun; Ock, Sun-A; Yoo, Jae-Gyu; Rho, Gyu-Jin

2012-10-01

The present study investigated the potential of minipig bone marrow-mesenchymal stem cells (BM-MSCs) to differentiate in vitro into neuron- and cardiomyocyte-like cells. Isolated BM-MSCs exhibited a fibroblast-like morphology, expressed CD29, CD44 and CD90, and differentiated into osteocytes, adipocytes and chondrocytes. Upon induction in two different neuronal specific media, most of BM-MSCs acquired the distinctive morphological features and positively stained for nestin, neurofilament-M (NF-M), neuronal nuclei (NeuN), β-tubulin, galactocerebroside (Gal-C) and glial fibrillary acidic protein (GFAP). Expression of nestin, GFAP and NF-M was further demonstrated by RT-PCR and RT-qPCR. Following cardiomyogenic induction, MSCs exhibited a stick-like morphology with extended cytoplasmic processes, and formed cluster-like structures. The expression of cardiac specific markers α-smooth muscle actin, cardiac troponin T, desmin and α-cardiac actin was positive for immunofluorescence staining, and further confirmed by RT-PCR and RT-qPCR. In conclusion, our results showed the in vitro differentiation ability of porcine BM-MSCs into neuron-like and cardiomyocyte-like cells. Copyright © 2011 Elsevier Ltd. All rights reserved.

Silica distinctively affects cell wall features and lignocellulosic saccharification with large enhancement on biomass production in rice.

PubMed

Zhang, Jing; Zou, Weihua; Li, Ying; Feng, Yongqing; Zhang, Hui; Wu, Zhiliang; Tu, Yuanyuan; Wang, Yanting; Cai, Xiwen; Peng, Liangcai

2015-10-01

Rice is a typical silicon-accumulating crop with enormous biomass residues for biofuels. Silica is a cell wall component, but its effect on the plant cell wall and biomass production remains largely unknown. In this study, a systems biology approach was performed using 42 distinct rice cell wall mutants. We found that silica levels are significantly positively correlated with three major wall polymers, indicating that silica is associated with the cell wall network. Silicon-supplied hydroculture analysis demonstrated that silica distinctively affects cell wall composition and major wall polymer features, including cellulose crystallinity (CrI), arabinose substitution degree (reverse Xyl/Ara) of xylans, and sinapyl alcohol (S) proportion in three typical rice mutants. Notably, the silicon supplement exhibited dual effects on biomass enzymatic digestibility in the mutant and wild type (NPB) after pre-treatments with 1% NaOH and 1% H2SO4. In addition, silicon supply largely enhanced plant height, mechanical strength and straw biomass production, suggesting that silica rescues mutant growth defects. Hence, this study provides potential approaches for silicon applications in biomass process and bioenergy rice breeding. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The Identification of Hail Storms in the Early Stage Using Time Series Analysis

NASA Astrophysics Data System (ADS)

Wang, Ping; Shi, Jinyu; Hou, Jinyi; Hu, Yan

2018-01-01

This study investigates the characteristics of hail storms and cumulonimbus storms in China from 2005 to 2016. Ten features are proposed to identify storm cells that can produce hail, especially in the early stage of hail formation. These features describe hail storms based on three factors: the height and thickness of the cell core, the radar echo intensity, and the overhang structure and the horizontal reflectivity gradient. The 10 features are transformed into two-dimensional comprehensive features by principal component analysis (PCA). The two comprehensive features are named the volume measurement comprehensive feature (VMCF) and the height-gradient comprehensive feature (HGCF). Through an analysis of 49 hail cases and 35 heavy rainfall cases with S-band radar data, the time series exhibit a distinct increase in VMCF or HGCF values in the early stage of a hail storm. However, the VMCF and HGCF values of heavy rainfall events remain relatively stable throughout the storm life cycle. An experiment involving real-storm events, including 31 hail cases and 33 heavy rainfall cases, indicated that the probability of detection of hail storms was 93.33% and the false alarm ratio was 15.66%. In the cases that could be successfully identified as hail storms, 80.00% were detected within 18 min of reaching a hail storm reflectivity of 40 dBZ.

Molecular differences between mature and immature dental pulp cells: Bioinformatics and preliminary results.

PubMed

Chen, Long; Jiang, Yifeng; Du, Zhen

2018-04-01

Although previous studies have demonstrated that dental pulp stem cells (DPSCs) from mature and immature teeth exhibit potential for multi-directional differentiation, the molecular and biological difference between the DPSCs from mature and immature permanent teeth has not been fully investigated. In the present study, 500 differentially expressed genes from dental pulp cells (DPCs) in mature and immature permanent teeth were obtained from the Gene Expression Omnibus online database. Based on bioinformatics analysis using the Database for Annotation, Visualization and Integrated Discovery, these genes were divided into a number of subgroups associated with immunity, inflammation and cell signaling. The results of the present study suggest that immune features, response to infection and cell signaling may be different in DPCs from mature and immature permanent teeth; furthermore, DPCs from immature permanent teeth may be more suitable for use in tissue engineering or stem cell therapy. The Online Mendelian Inheritance in Man database stated that Sonic Hedgehog (SHH), a differentially expressed gene in DPCs from mature and immature permanent teeth, serves a crucial role in the development of craniofacial tissues, including teeth, which further confirmed that SHH may cause DPCs from mature and immature permanent teeth to exhibit different biological characteristics. The Search Tool for the Retrieval of Interacting Genes/Proteins database revealed that SHH has functional protein associations with a number of other proteins, including Glioma-associated oncogene (GLI)1, GLI2, growth arrest-specific protein 1, bone morphogenetic protein (BMP)2 and BMP4, in mice and humans. It was also demonstrated that SHH may interact with other genes to regulate the biological characteristics of DPCs. The results of the present study may provide a useful reference basis for selecting suitable DPSCs and molecules for the treatment of these cells to optimize features for tissue engineering or stem cell therapy. Quantitative polymerase chain reaction should be performed to confirm the differential expression of these genes prior to the beginning of a functional study.

Chromosome Mis-segregation Generates Cell-Cycle-Arrested Cells with Complex Karyotypes that Are Eliminated by the Immune System.

PubMed

Santaguida, Stefano; Richardson, Amelia; Iyer, Divya Ramalingam; M'Saad, Ons; Zasadil, Lauren; Knouse, Kristin A; Wong, Yao Liang; Rhind, Nicholas; Desai, Arshad; Amon, Angelika

2017-06-19

Aneuploidy, a state of karyotype imbalance, is a hallmark of cancer. Changes in chromosome copy number have been proposed to drive disease by modulating the dosage of cancer driver genes and by promoting cancer genome evolution. Given the potential of cells with abnormal karyotypes to become cancerous, do pathways that limit the prevalence of such cells exist? By investigating the immediate consequences of aneuploidy on cell physiology, we identified mechanisms that eliminate aneuploid cells. We find that chromosome mis-segregation leads to further genomic instability that ultimately causes cell-cycle arrest. We further show that cells with complex karyotypes exhibit features of senescence and produce pro-inflammatory signals that promote their clearance by the immune system. We propose that cells with abnormal karyotypes generate a signal for their own elimination that may serve as a means for cancer cell immunosurveillance. Copyright © 2017 Elsevier Inc. All rights reserved.

Fluorescence imaging analysis of taxol-induced ASTC-a-1 cell death with cell swelling and cytoplasmic vacuolization

NASA Astrophysics Data System (ADS)

Chen, Tong-sheng; Sun, Lei; Wang, Longxiang; Wang, Huiying

2008-02-01

Taxol (Paclitaxel), an isolated component from the bark of the Pacific yew Taxus brevifolia, exhibits a broad spectrum of clinical activity against human cancers. Taxol can promote microtubule (MT) assembly, inhibit depolymerization, and change MT dynamics, resulting in disruption of the normal reorganization of the microtubule network required for mitosis and cell proliferation. However, the molecular mechanism of taxol-induced cell death is still unclear. In this report, CCK-8 was used to assay the inhibition of taxol on the human lung adenocarcinoma (ASTC-a-1) cells viability, confocal fluorescence microscope was used to monitor the morphology changes of cells with taxol treatment. We for the first time describe the characteristics of taxol-induced cells swelling, cytoplasmic vacuolization and cell death. Taxol induced swelling, cytoplasmatic vacuolization and cell death without cell shrinkage and membrane rupture. These features differ from those of apoptosis and resemble the paraptosis, a novel nonapoptotic PCD.

Highly aggressive ALK-positive anaplastic large cell lymphoma with a leukemic phase and multi-organ involvement: a report of three cases and a review of the literature.

PubMed

Grewal, Jaspreet S; Smith, Lauren B; Winegarden, Jerome D; Krauss, John C; Tworek, Joseph A; Schnitzer, Bertram

2007-07-01

Anaplastic large cell lymphoma (ALCL) is an aggressive neoplasm of T- or null cell phenotype and is recognized as a distinct clinicopathologic subtype of non-Hodgkin lymphoma (NHL) in the revised World Health Organization (WHO) classification of hematopoietic neoplasms. It is rarely associated with leukemic phase. Most cases with leukemic involvement are the small cell variant of ALCL. These cases often lack the pleomorphism seen in the common variant of ALCL and may be misdiagnosed. We report a series of three patients who presented with leukemic phase ALCL. The patients included an 11-year-old boy, a 29-year-old man, and a 59-year-old woman. The clinical and pathologic features of these cases are reviewed. The patients in our case series with leukemic phase ALCL exhibited rare clinical features. The patients presented with massive extranodal disease involving cerebrospinal fluid (CSF), liver, spleen, lungs, and bone marrow. CSF involvement was documented morphologically as well as by flow cytometry in two patients. Two of the patients had small cell variant and the third patient had common type ALCL. The neoplastic cells in all three patients were ALK positive; however these patients died within months of diagnosis. Leukemic phase ALCL is rare, and behaves in an aggressive manner. Some, but not all, cases in the literature presenting with peripheral blood involvement had small cell variant ALCL, as seen in two of our cases. The leukemic phase of ALCL should be considered when a T-cell leukemia with unusual morphologic features is encountered.

Perivascular epithelioid cell tumor (PEComa) of the urinary bladder associated with Xp11 translocation.

PubMed

Russell, Christopher M; Buethe, David D; Dickinson, Shohreh; Sexton, Wade J

2014-01-01

Perivascular epithelioid cell-containing tumors (PEComas) represent a rare family of neoplasms. Their dichotomous phenotypic features, including both myogenic and mylanocytic features, can make a definitive diagnosis difficult. Such tumors have been associated with the overexpression of transcription factor E3 (TFE3). An Xp11 translocation could account for the aberrant activity of TFE3 but has never before been described in affiliation with a PEComa of the urinary bladder. While PEComas of the bladder have exhibited benign clinical courses to date, here we present an intravesical PEComa shown to have an Xp11 translocation and resultant overexpression of TFE3, indicating an aggressive, metastatic nature. No consistent tumor characteristics have proven accurate at identifying aggressive tumors. However, mTOR inhibitors offer a mechanistic management strategy when systemic therapy is warranted.

Identification of Novel Desiccation-Tolerant S. cerevisiae Strains for Deep Space Biosensors

NASA Technical Reports Server (NTRS)

Tieze, Sofia Massaro; Santa Maria, Sergio R.; Liddell, Lauren C.; Bhattacharya, Sharmila

2017-01-01

NASA's BioSentinel mission, a secondary payload that will fly on the Space Launch System's first Exploration Mission (EM-1), utilizes the budding yeast S. cerevisiae to study the biological response to the deep space radiation environment. Yeast samples are desiccated prior to launch to suspend growth and metabolism while the spacecraft travels to its target heliocentric orbit beyond Low Earth Orbit. Each sample is then rehydrated at the desired time points to reactivate the cells. A major risk in this mission is the loss of cell viability that occurs in the recovery period following the desiccation and rehydration process. Cell survival is essential for the detection of the biological response to features in the deep space environment, including ionizing radiation. The aim of this study is to mitigate viable cell loss in future biosensors by identifying mutations and genes that confer tolerance to desiccation stress in rad51, a radiation-sensitive yeast strain. We initiated a screen for desiccation-tolerance after rehydrating cells that were desiccated for three years, and selected various clones exhibiting robust growth. To verify retention of radiation sensitivity in the isolated clones - a crucial feature for a successful biosensor - we exposed them to ionizing radiation. Finally, to elucidate the genetic and molecular bases for observed desiccation-tolerance, we will perform whole-genome sequencing of those rad51 clones that exhibit both robust growth and radiation sensitivity following desiccation. The identification and characterization of desiccation-tolerant strains will allow us to engineer a biological model that will be resilient in face of the challenges of the deep space environment, and will thus ensure the experimental success of future biosensor missions.

Identification of Novel Desiccation-Tolerant S. cerevisiae Strains for Deep Space Biosensors

NASA Technical Reports Server (NTRS)

Tieze, Sofia Massaro; Santa Maria, Sergio R.; Liddell, Lauren; Bhattacharya, Sharmila

2017-01-01

NASA's BioSentinel mission, a secondary payload that will fly on the Space Launch Systems first Exploration Mission (EM-1), utilizes the budding yeast S. cerevisiae to study the biological response to the deep space radiation environment. Yeast samples are desiccated prior to launch to suspend growth and metabolism while the spacecraft travels to its target heliocentric orbit beyond Low Earth Orbit. Each sample is then rehydrated at the desired time points to reactivate the cells. A major risk in this mission is the loss of cell viability that occurs in the recovery period following the desiccation and rehydration process. Cell survival is essential for the detection of the biological response to features in the deep space environment, including ionizing radiation.The aim of this study is to mitigate viable cell loss in future biosensors by identifying mutations and genes that confer tolerance to desiccation stress in rad51, a radiation-sensitive yeast strain. We initiated a screen for desiccation-tolerance after rehydrating cells that were desiccated for three years, and selected various clones exhibiting robust growth. To verify retention of radiation sensitivity in the isolated clonesa crucial feature for a successful biosensorwe exposed them to ionizing radiation. Finally, to elucidate the genetic and molecular bases for observed desiccation-tolerance, we will perform whole-genome sequencing of those rad51 clones that exhibit both robust growth and radiation sensitivity following desiccation. The identification and characterization of desiccation-tolerant strains will allow us to engineer a biological model that will be resilient in face of the challenges of the deep space environment, and will thus ensure the experimental success of future biosensor missions.

Invasive urothelial carcinoma exhibiting basal cell immunohistochemical markers: A variant of urothelial carcinoma associated with aggressive features.

PubMed

Mai, Kien T; Truong, Luan D; Ball, Christopher G; Williams, Phillip; Flood, Trevor A; Belanger, Eric C

2015-08-01

We characterize invasive urothelial carcinoma (UC) exhibiting urothelial basal cell immunohistochemical markers. Consecutive invasive UCs were immunostained with CK20 and urothelial basal cell markers, cytokeratin 5 (CK5)/CD44. Immunostaining for CK5 and CD44 was scored as follows: positive for staining of more than 25% thickness of the epithelial nest or epithelium and low for lesser immunoreactivity. Invasive urothelial carcinoma (UC) exhibiting positive CK5/CD44 staining was designated as basal-like UC (BUC). In this study, of 251 invasive UC (pT1 in 57% and pT2-4 in 43%), BUC accounted for 40% of cases (accounting for most pT2-4 UC) and often presented as non-papillary UC without previous history of UC. In addition, BUC exhibited uniform nuclei with lesser degree of atypia than non BUC and decreased or negative cytokeratin 20 reactivity. Nested and microcystic variants of UC immunohistochemically stained as BUCs. Invasive non-BUCs were often papillary with marked cytologic atypia and pleomorphism, and accounted for most pT1 UC. The rates of perivesical invasion, lymph node and distant metastases were higher for BUC than non-BUC. All nine cases with absent/minimal residual in situ UC in 102 radical cystectomy specimens were from invasive non-BUC. BUC is distinguished from non-BUC due to this aggressive behavior, distinct immunohistochemical profile, and predominant non-papillary architecture. Our findings are consistent with recent studies identifying a subtype of muscle-invasive UC with molecular expression of basal cell and luminal cell molecular profiles. Our study further supports categorizing invasive UCs into these subtypes with different biological behaviors, possibly contributing to better therapeutic strategies. Copyright © 2015 Elsevier GmbH. All rights reserved.

Adipose tissue-deprived stem cells acquire cementoblast features treated with dental follicle cell conditioned medium containing dentin non-collagenous proteins in vitro

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

Wen, Xiujie; Nie, Xin; Zhang, Li

Highlights: {yields} In this study we examine the effects of dental follicle cell conditioned medium (DFCCM) containing dentin non-collagenous proteins (dNCPs) on differentiation of ADSCs. {yields} We examined that ADSCs treated with dNCPs/DFCCM underwent morphological changes and significantly lost their proliferative capacity. {yields} dNCPs/DFCCM enhanced the mineralization behaviour and mineralization-related marker expression of ADSCs. {yields} ADSCs acquired cementoblast features in vitro with dNCPs/DFCCM treatment. -- Abstract: Adipose tissue-derived stem cells (ADSCs), which are easily harvested and show excellent pluripotency potential, have generated considerable interest in regenerative medicine. In this study, the differentiation of ADSCs was assessed after treatment with dentalmore » follicle cell conditioned medium (DFCCM) containing dentin non-collagenous proteins (dNCPs). ADSCs exhibited a fibroblast-like morphology and high proliferative capacity. However, after treatment with dNCPs/DFCCM, ADSCs changed from a fibroblast-like to cementoblast-like morphology and significantly lost their proliferative capacity. Alkaline phosphatase activity and in vitro mineralization behaviour of ADSCs were significantly enhanced. Mineralization-related markers including cementum attachment protein, bone sialoprotein, osteocalcin, osteopontin and osteonectin were detected at mRNA or protein levels, whereas dentin sialophosphoprotein and dentin sialoprotein were not detected, implying a cementoblast-like phenotype. These results demonstrate that ADSCs acquired cementoblast features in vitro with dNCPs/DFCCM treatment and could be a potential source of cementogenic cells for periodontal regeneration.« less

Laser-induced patterns on metals and polymers for biomimetic surface engineering

NASA Astrophysics Data System (ADS)

Kietzig, Anne-Marie; Lehr, Jorge; Matus, Luke; Liang, Fang

2014-03-01

One common feature of many functional surfaces found in nature is their modular composition often exhibiting several length scales. Prominent natural examples for extreme behaviors can be named in various plant leaf (rose, peanut, lotus) or animal toe surfaces (Gecko, tree frog). Influence factors of interest are the surface's chemical composition, its microstructure, its organized or random roughness and hence the resulting surface wetting and adhesion character. Femtosecond (fs) laser micromachining offers a possibility to render all these factors in one single processing step on metallic and polymeric surfaces. Exemplarily, studies on Titanium and PTFE are shown, where the dependence of the resulting feature sizes on lasing intensity is investigated. While Ti surfaces show rigid surface patterns of micrometer scaled features with superimposed nanostructures, PTFE exhibits elastic hairy structures of nanometric diameter, which upon a certain threshold tend to bundle to larger features. Both surface patterns can be adjusted to mimic specific wetting and flow behaviour as seen on natural examples. Therefore, fs-laser micromachining is suggested as an interesting industrially scalable technique to pattern and fine-tune the surface wettability of a surface to the desired extends in one process step. Possible applications can be seen with surfaces, which require specific wetting, fouling, icing, friction or cell adhesion behaviour.

The hallmarks of fibroblast ageing.

PubMed

Tigges, Julia; Krutmann, Jean; Fritsche, Ellen; Haendeler, Judith; Schaal, Heiner; Fischer, Jens W; Kalfalah, Faiza; Reinke, Hans; Reifenberger, Guido; Stühler, Kai; Ventura, Natascia; Gundermann, Sabrina; Boukamp, Petra; Boege, Fritz

2014-06-01

Ageing is influenced by the intrinsic disposition delineating what is maximally possible and extrinsic factors determining how that frame is individually exploited. Intrinsic and extrinsic ageing processes act on the dermis, a post-mitotic skin compartment mainly consisting of extracellular matrix and fibroblasts. Dermal fibroblasts are long-lived cells constantly undergoing damage accumulation and (mal-)adaptation, thus constituting a powerful indicator system for human ageing. Here, we use the systematic of ubiquitous hallmarks of ageing (Lopez-Otin et al., 2013, Cell 153) to categorise the available knowledge regarding dermal fibroblast ageing. We discriminate processes inducible in culture from phenomena apparent in skin biopsies or primary cells from old donors, coming to the following conclusions: (i) Fibroblasts aged in culture exhibit most of the established, ubiquitous hallmarks of ageing. (ii) Not all of these hallmarks have been detected or investigated in fibroblasts aged in situ (in the skin). (iii) Dermal fibroblasts aged in vitro and in vivo exhibit additional features currently not considered ubiquitous hallmarks of ageing. (iv) The ageing process of dermal fibroblasts in their physiological tissue environment has only been partially elucidated, although these cells have been a preferred model of cell ageing in vitro for decades. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Arabinogalactan proteins in root and pollen-tube cells: distribution and functional aspects

PubMed Central

Nguema-Ona, Eric; Coimbra, Sílvia; Vicré-Gibouin, Maïté; Mollet, Jean-Claude; Driouich, Azeddine

2012-01-01

Background Arabinogalactan proteins (AGPs) are complex proteoglycans of the cell wall found in the entire plant kingdom and in almost all plant organs. AGPs encompass a large group of heavily glycosylated cell-wall proteins which share common features, including the presence of glycan chains especially enriched in arabinose and galactose and a protein backbone particularly rich in hydroxyproline residues. However, AGPs also exhibit strong heterogeneities among their members in various plant species. AGP ubiquity in plants suggests these proteoglycans are fundamental players for plant survival and development. Scope In this review, we first present an overview of current knowledge and specific features of AGPs. A section devoted to major tools used to study AGPs is also presented. We then discuss the distribution of AGPs as well as various aspects of their functional properties in root tissues and pollen tubes. This review also suggests novel directions of research on the role of AGPs in the biology of roots and pollen tubes. PMID:22786747

The scaling features of the 3D organization of chromosomes are highlighted by a transformation à la Kadanoff of Hi-C data

NASA Astrophysics Data System (ADS)

Chiariello, Andrea M.; Bianco, Simona; Annunziatella, Carlo; Esposito, Andrea; Nicodemi, Mario

2017-11-01

Technologies such as Hi-C and GAM have revealed that chromosomes are not randomly folded into the nucleus of cells, but are composed by a sequence of contact domains (TADs), each typically 0.5 Mb long. However, the larger scale organization of the genome remains still not well understood. To investigate the scaling behaviour of chromosome folding, here we apply an approach à la Kadanoff, inspired by the Renormalization Group theory, to Hi-C interaction data, across different cell types and chromosomes. We find that the genome is characterized by complex scaling features, where the average size of contact domains exhibits a power-law behaviour with the rescaling level. That is compatible with the existence of contact domains extending across length scales up to chromosomal sizes. The scaling exponent is statistically indistinguishable among the different murine cell types analysed. These results point toward a scenario of a universal higher-order spatial architecture of the genome, which could reflect fundamental, organizational principles.

Anti-trypanosomal activity of cationic N-heterocyclic carbene gold(I) complexes.

PubMed

Winter, Isabel; Lockhauserbäumer, Julia; Lallinger-Kube, Gertrud; Schobert, Rainer; Ersfeld, Klaus; Biersack, Bernhard

2017-06-01

Two gold(I) N-heterocyclic carbene complexes 1a and 1b were tested for their anti-trypanosomal activity against Trypanosoma brucei parasites. Both gold compounds exhibited excellent anti-trypanosomal activity (IC 50 =0.9-3.0nM). The effects of the gold complexes 1a and 1b on the T. b. brucei cytoskeleton were evaluated. Rapid detachment of the flagellum from the cell body occurred after treatment with the gold complexes. In addition, a quick and complete degeneration of the parasitic cytoskeleton was induced by the gold complexes, only the microtubules of the detached flagellum remained intact. Both gold compounds 1a and 1b feature selective anti-trypanosomal agents and were distinctly more active against T. b. brucei cells than against human HeLa cells. Thus, the gold complexes 1a and 1b feature promising drug candidates for the treatment of trypanosome infections such as sleeping sickness (human African Trypanosomiasis caused by Trypanosoma brucei parasites). Copyright © 2017 Elsevier B.V. All rights reserved.

Necrotic enlargement of cone photoreceptor cells and the release of high-mobility group box-1 in retinitis pigmentosa

PubMed Central

Murakami, Y; Ikeda, Y; Nakatake, S; Tachibana, T; Fujiwara, K; Yoshida, N; Notomi, S; Nakao, S; Hisatomi, T; Miller, J W; Vavvas, DG; Sonoda, KH; Ishibashi, T

2015-01-01

Retinitis pigmentosa (RP) refers to a group of inherited retinal degenerations resulting form rod and cone photoreceptor cell death. The rod cell death due to deleterious genetic mutations has been shown to occur mainly through apoptosis, whereas the mechanisms and features of the secondary cone cell death have not been fully elucidated. Our previous study showed that the cone cell death in rd10 mice, an animal model of RP, involves necrotic features and is partly mediated by the receptor interacting protein kinase. However, the relevancy of necrotic cone cell death in human RP patients remains unknown. In the present study, we showed that dying cone cells in rd10 mice exhibited cellular enlargement, along with necrotic changes such as cellular swelling and mitochondrial rupture. In human eyes, live imaging of cone cells by adaptive optics scanning laser ophthalmoscopy revealed significantly increased percentages of enlarged cone cells in the RP patients compared with the control subjects. The vitreous of the RP patients contained significantly higher levels of high-mobility group box-1, which is released extracellularly associated with necrotic cell death. These findings suggest that necrotic enlargement of cone cells is involved in the process of cone degeneration, and that necrosis may be a novel target to prevent or delay the loss of cone-mediated central vision in RP. PMID:27551484

Potential Use of Human Periapical Cyst-Mesenchymal Stem Cells (hPCy-MSCs) as a Novel Stem Cell Source for Regenerative Medicine Applications

PubMed Central

Tatullo, Marco; Codispoti, Bruna; Pacifici, Andrea; Palmieri, Francesca; Marrelli, Massimo; Pacifici, Luciano; Paduano, Francesco

2017-01-01

Mesenchymal stem cells (MSCs) are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs) exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications. PMID:29259970

Potential Use of Human Periapical Cyst-Mesenchymal Stem Cells (hPCy-MSCs) as a Novel Stem Cell Source for Regenerative Medicine Applications.

PubMed

Tatullo, Marco; Codispoti, Bruna; Pacifici, Andrea; Palmieri, Francesca; Marrelli, Massimo; Pacifici, Luciano; Paduano, Francesco

2017-01-01

Mesenchymal stem cells (MSCs) are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs) exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications.

Metabolic Profile of Oral Squamous Carcinoma Cell Lines Relies on a Higher Demand of Lipid Metabolism in Metastatic Cells

PubMed Central

Sant’Anna-Silva, Ana Carolina B.; Santos, Gilson C.; Campos, Samir P. Costa; Oliveira Gomes, André Marco; Pérez-Valencia, Juan Alberto; Rumjanek, Franklin David

2018-01-01

Tumor cells are subjected to a broad range of selective pressures. As a result of the imposed stress, subpopulations of surviving cells exhibit individual biochemical phenotypes that reflect metabolic reprograming. The present work aimed at investigating metabolic parameters of cells displaying increasing degrees of metastatic potential. The metabolites present in cell extracts fraction of tongue fibroblasts and of cell lines derived from human tongue squamous cell carcinoma lineages displaying increasing metastatic potential (SCC9 ZsG, LN1 and LN2) were analyzed by 1H NMR (nuclear magnetic resonance) spectroscopy. Living, intact cells were also examined by the non-invasive method of fluorescence lifetime imaging microscopy (FLIM) based on the auto fluorescence of endogenous NADH. The cell lines reproducibly exhibited distinct metabolic profiles confirmed by Partial Least-Square Discriminant Analysis (PLS-DA) of the spectra. Measurement of endogenous free and bound NAD(P)H relative concentrations in the intact cell lines showed that ZsG and LN1 cells displayed high heterogeneity in the energy metabolism, indicating that the cells would oscillate between glycolysis and oxidative metabolism depending on the microenvironment’s composition. However, LN2 cells appeared to have more contributions to the oxidative status, displaying a lower NAD(P)H free/bound ratio. Functional experiments of energy metabolism, mitochondrial physiology, and proliferation assays revealed that all lineages exhibited similar energy features, although resorting to different bioenergetics strategies to face metabolic demands. These differentiated functions may also promote metastasis. We propose that lipid metabolism is related to the increased invasiveness as a result of the accumulation of malonate, methyl malonic acid, n-acetyl and unsaturated fatty acids (CH2)n in parallel with the metastatic potential progression, thus suggesting that the NAD(P)H reflected the lipid catabolic/anabolic pathways. PMID:29456966

Ribosomal and hematopoietic defects in induced pluripotent stem cells derived from Diamond Blackfan anemia patients

PubMed Central

Garçon, Loïc; Ge, Jingping; Manjunath, Shwetha H.; Mills, Jason A.; Apicella, Marisa; Parikh, Shefali; Sullivan, Lisa M.; Podsakoff, Gregory M.; Gadue, Paul; French, Deborah L.; Mason, Philip J.; Bessler, Monica

2013-01-01

Diamond Blackfan anemia (DBA) is a congenital disorder with erythroid (Ery) hypoplasia and tissue morphogenic abnormalities. Most DBA cases are caused by heterozygous null mutations in genes encoding ribosomal proteins. Understanding how haploinsufficiency of these ubiquitous proteins causes DBA is hampered by limited availability of tissues from affected patients. We generated induced pluripotent stem cells (iPSCs) from fibroblasts of DBA patients carrying mutations in RPS19 and RPL5. Compared with controls, DBA fibroblasts formed iPSCs inefficiently, although we obtained 1 stable clone from each fibroblast line. RPS19-mutated iPSCs exhibited defects in 40S (small) ribosomal subunit assembly and production of 18S ribosomal RNA (rRNA). Upon induced differentiation, the mutant clone exhibited globally impaired hematopoiesis, with the Ery lineage affected most profoundly. RPL5-mutated iPSCs exhibited defective 60S (large) ribosomal subunit assembly, accumulation of 12S pre-rRNA, and impaired erythropoiesis. In both mutant iPSC lines, genetic correction of ribosomal protein deficiency via complementary DNA transfer into the “safe harbor” AAVS1 locus alleviated abnormalities in ribosome biogenesis and hematopoiesis. Our studies show that pathological features of DBA are recapitulated by iPSCs, provide a renewable source of cells to model various tissue defects, and demonstrate proof of principle for genetic correction strategies in patient stem cells. PMID:23744582

Ribosomal and hematopoietic defects in induced pluripotent stem cells derived from Diamond Blackfan anemia patients.

PubMed

Garçon, Loïc; Ge, Jingping; Manjunath, Shwetha H; Mills, Jason A; Apicella, Marisa; Parikh, Shefali; Sullivan, Lisa M; Podsakoff, Gregory M; Gadue, Paul; French, Deborah L; Mason, Philip J; Bessler, Monica; Weiss, Mitchell J

2013-08-08

Diamond Blackfan anemia (DBA) is a congenital disorder with erythroid (Ery) hypoplasia and tissue morphogenic abnormalities. Most DBA cases are caused by heterozygous null mutations in genes encoding ribosomal proteins. Understanding how haploinsufficiency of these ubiquitous proteins causes DBA is hampered by limited availability of tissues from affected patients. We generated induced pluripotent stem cells (iPSCs) from fibroblasts of DBA patients carrying mutations in RPS19 and RPL5. Compared with controls, DBA fibroblasts formed iPSCs inefficiently, although we obtained 1 stable clone from each fibroblast line. RPS19-mutated iPSCs exhibited defects in 40S (small) ribosomal subunit assembly and production of 18S ribosomal RNA (rRNA). Upon induced differentiation, the mutant clone exhibited globally impaired hematopoiesis, with the Ery lineage affected most profoundly. RPL5-mutated iPSCs exhibited defective 60S (large) ribosomal subunit assembly, accumulation of 12S pre-rRNA, and impaired erythropoiesis. In both mutant iPSC lines, genetic correction of ribosomal protein deficiency via complementary DNA transfer into the "safe harbor" AAVS1 locus alleviated abnormalities in ribosome biogenesis and hematopoiesis. Our studies show that pathological features of DBA are recapitulated by iPSCs, provide a renewable source of cells to model various tissue defects, and demonstrate proof of principle for genetic correction strategies in patient stem cells.

Can mesenchymal cells undergo collective cell migration?

PubMed Central

Theveneau, Eric

2011-01-01

Cell migration is critical for proper development of the embryo and is also used by many cell types to perform their physiological function. For instance, cell migration is essential for immune cells to monitor the body and for epithelial cells to heal a wound whereas, in cancer cells, acquisition of migratory capabilities is a critical step toward malignancy. Migratory cells are often categorized into two groups: (1) mesenchymal cells, produced by an epithelium-to-mesenchyme transition, that undergo solitary migration and (2) epithelial-like cells which migrate collectively. However, on some occasions, mesenchymal cells may travel in large, dense groups and exhibit key features of collectively migrating cells such as coordination and cooperation. Here, using data published on neural crest cells, a highly invasive mesenchymal cell population that extensively migrate throughout the embryo, we explore the idea that mesenchymal cells, including cancer cells, might be able to undergo collective cell migration under certain conditions and discuss how they could do so. PMID:22274714

Phosphatidylserine and GTPase activation control Cdc42 nanoclustering to counter dissipative diffusion.

PubMed

Sartorel, Elodie; Ünlü, Caner; Jose, Mini; Massoni-Laporte, Aurélie; Meca, Julien; Sibarita, Jean-Baptiste; McCusker, Derek

2018-04-18

The anisotropic organization of plasma membrane constituents is indicative of mechanisms that drive the membrane away from equilibrium. However, defining these mechanisms is challenging due to the short spatio-temporal scales at which diffusion operates. Here, we use high-density single protein tracking combined with photoactivation localization microscopy (sptPALM) to monitor Cdc42 in budding yeast, a system in which Cdc42 exhibits anisotropic organization. Cdc42 exhibited reduced mobility at the cell pole, where it was organized in nanoclusters. The Cdc42 nanoclusters were larger at the cell pole than those observed elsewhere in the cell. These features were exacerbated in cells expressing Cdc42-GTP, and were dependent on the scaffold Bem1, which contributed to the range of mobility and nanocluster size exhibited by Cdc42. The lipid environment, in particular phosphatidylserine levels, also played a role in regulating Cdc42 nanoclustering. These studies reveal how the mobility of a Rho GTPase is controlled to counter the depletive effects of diffusion, thus stabilizing Cdc42 on the plasma membrane and sustaining cell polarity. Movie S1 Movie S1 sptPALM imaging of live yeast expressing Pil1-mEOS expressed at the genomic locus. Pil1-mEOS was simultaneously photo-converted with a 405 nm laser and imaged with a 561 nm laser using HiLo illumination. Images were acquired at 20 ms intervals, of which 300 frames are shown at 7 frames per second.

Neurons derived from different brain regions are inherently different in vitro: a novel multiregional brain-on-a-chip.

PubMed

Dauth, Stephanie; Maoz, Ben M; Sheehy, Sean P; Hemphill, Matthew A; Murty, Tara; Macedonia, Mary Kate; Greer, Angie M; Budnik, Bogdan; Parker, Kevin Kit

2017-03-01

Brain in vitro models are critically important to developing our understanding of basic nervous system cellular physiology, potential neurotoxic effects of chemicals, and specific cellular mechanisms of many disease states. In this study, we sought to address key shortcomings of current brain in vitro models: the scarcity of comparative data for cells originating from distinct brain regions and the lack of multiregional brain in vitro models. We demonstrated that rat neurons from different brain regions exhibit unique profiles regarding their cell composition, protein expression, metabolism, and electrical activity in vitro. In vivo, the brain is unique in its structural and functional organization, and the interactions and communication between different brain areas are essential components of proper brain function. This fact and the observation that neurons from different areas of the brain exhibit unique behaviors in vitro underline the importance of establishing multiregional brain in vitro models. Therefore, we here developed a multiregional brain-on-a-chip and observed a reduction of overall firing activity, as well as altered amounts of astrocytes and specific neuronal cell types compared with separately cultured neurons. Furthermore, this multiregional model was used to study the effects of phencyclidine, a drug known to induce schizophrenia-like symptoms in vivo, on individual brain areas separately while monitoring downstream effects on interconnected regions. Overall, this work provides a comparison of cells from different brain regions in vitro and introduces a multiregional brain-on-a-chip that enables the development of unique disease models incorporating essential in vivo features. NEW & NOTEWORTHY Due to the scarcity of comparative data for cells from different brain regions in vitro, we demonstrated that neurons isolated from distinct brain areas exhibit unique behaviors in vitro. Moreover, in vivo proper brain function is dependent on the connection and communication of several brain regions, underlining the importance of developing multiregional brain in vitro models. We introduced a novel brain-on-a-chip model, implementing essential in vivo features, such as different brain areas and their functional connections. Copyright © 2017 the American Physiological Society.

Neurons derived from different brain regions are inherently different in vitro: a novel multiregional brain-on-a-chip

PubMed Central

Dauth, Stephanie; Maoz, Ben M.; Sheehy, Sean P.; Hemphill, Matthew A.; Murty, Tara; Macedonia, Mary Kate; Greer, Angie M.; Budnik, Bogdan

2017-01-01

Brain in vitro models are critically important to developing our understanding of basic nervous system cellular physiology, potential neurotoxic effects of chemicals, and specific cellular mechanisms of many disease states. In this study, we sought to address key shortcomings of current brain in vitro models: the scarcity of comparative data for cells originating from distinct brain regions and the lack of multiregional brain in vitro models. We demonstrated that rat neurons from different brain regions exhibit unique profiles regarding their cell composition, protein expression, metabolism, and electrical activity in vitro. In vivo, the brain is unique in its structural and functional organization, and the interactions and communication between different brain areas are essential components of proper brain function. This fact and the observation that neurons from different areas of the brain exhibit unique behaviors in vitro underline the importance of establishing multiregional brain in vitro models. Therefore, we here developed a multiregional brain-on-a-chip and observed a reduction of overall firing activity, as well as altered amounts of astrocytes and specific neuronal cell types compared with separately cultured neurons. Furthermore, this multiregional model was used to study the effects of phencyclidine, a drug known to induce schizophrenia-like symptoms in vivo, on individual brain areas separately while monitoring downstream effects on interconnected regions. Overall, this work provides a comparison of cells from different brain regions in vitro and introduces a multiregional brain-on-a-chip that enables the development of unique disease models incorporating essential in vivo features. NEW & NOTEWORTHY Due to the scarcity of comparative data for cells from different brain regions in vitro, we demonstrated that neurons isolated from distinct brain areas exhibit unique behaviors in vitro. Moreover, in vivo proper brain function is dependent on the connection and communication of several brain regions, underlining the importance of developing multiregional brain in vitro models. We introduced a novel brain-on-a-chip model, implementing essential in vivo features, such as different brain areas and their functional connections. PMID:28031399

Comparative Gene Expression Analyses Reveal Distinct Molecular Signatures between Differentially Reprogrammed Cardiomyocytes.

PubMed

Zhou, Yang; Wang, Li; Liu, Ziqing; Alimohamadi, Sahar; Yin, Chaoying; Liu, Jiandong; Qian, Li

2017-09-26

Cardiomyocytes derived from induced pluripotent stem cells (iPSC-CMs) or directly reprogrammed from non-myocytes (induced cardiomyocytes [iCMs]) are promising sources for heart regeneration or disease modeling. However, the similarities and differences between iPSC-CMs and iCMs are still unknown. Here, we performed transcriptome analyses of beating iPSC-CMs and iCMs generated from cardiac fibroblasts (CFs) of the same origin. Although both iPSC-CMs and iCMs establish CM-like molecular features globally, iPSC-CMs exhibit a relatively hyperdynamic epigenetic status, whereas iCMs exhibit a maturation status that more closely resembles that of adult CMs. Based on gene expression of metabolic enzymes, iPSC-CMs primarily employ glycolysis, whereas iCMs utilize fatty acid oxidation as the main pathway. Importantly, iPSC-CMs and iCMs exhibit different cell-cycle status, alteration of which influenced their maturation. Therefore, our study provides a foundation for understanding the pros and cons of different reprogramming approaches. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Early detection of skin cancer via terahertz spectral profiling and 3D imaging.

PubMed

Rahman, Anis; Rahman, Aunik K; Rao, Babar

2016-08-15

Terahertz scanning reflectometry, terahertz 3D imaging and terahertz time-domain spectroscopy have been used to identify features in human skin biopsy samples diagnosed for basal cell carcinoma (BCC) and compared with healthy skin samples. It was found from the 3D images that the healthy skin samples exhibit regular cellular pattern while the BCC skin samples indicate lack of regular cell pattern. The skin is a highly layered structure organ; this is evident from the thickness profile via a scan through the thickness of the healthy skin samples, where, the reflected intensity of the terahertz beam exhibits fluctuations originating from different skin layers. Compared to the healthy skin samples, the BCC samples' profiles exhibit significantly diminished layer definition; thus indicating a lack of cellular order. In addition, terahertz time-domain spectroscopy reveals significant and quantifiable differences between the healthy and BCC skin samples. Thus, a combination of three different terahertz techniques constitutes a conclusive route for detecting the BCC condition on a cellular level compared to the healthy skin. Copyright © 2016 Elsevier B.V. All rights reserved.

HPV-related Multiphenotypic Sinonasal Carcinoma: An Expanded Series of 49 Cases of the Tumor Formerly Known as HPV-related Carcinoma With Adenoid Cystic Carcinoma-like Features.

PubMed

Bishop, Justin A; Andreasen, Simon; Hang, Jen-Fan; Bullock, Martin J; Chen, Tiffany Y; Franchi, Alessandro; Garcia, Joaquin J; Gnepp, Douglas R; Gomez-Fernandez, Carmen R; Ihrler, Stephan; Kuo, Ying-Ju; Lewis, James S; Magliocca, Kelly R; Pambuccian, Stefan; Sandison, Ann; Uro-Coste, Emmanuelle; Stelow, Edward; Kiss, Katalin; Westra, William H

2017-12-01

Human papillomavirus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC), originally known as HPV-related carcinoma with adenoid cystic carcinoma-like features, is a peculiar neoplasm that is restricted to the sinonasal tract, exhibits features of both a surface-derived and salivary gland carcinoma (particularly adenoid cystic carcinoma), and is associated with high-risk HPV. Given the limited number of published cases, the full clinicopathologic spectrum of this neoplasm is unclear. Here, we present an updated experience of 49 cases. All cases of HMSC were obtained from the authors' files. Immunohistochemistry for p16, c-kit, and myoepithelial cell markers (S100, actin, calponin, p63, and/or p40) was performed along with RNA in situ hybridization for HPV (type 33-specific as well as a high-risk cocktail). Fluorescence in situ hybridization studies for fusions of MYB, NFIB, and MYBL1 was performed on a subset of cases. Clinical follow-up was obtained from medical records. A total of 49 cases of HMSC were collected. Twenty-eight (57%) were from women and 18 (43%) from men, ranging in age from 28 to 90 years (mean, 54 y). Of 40 cases with detailed staging information, 43% of HMSCs presented with a high T-stage (T3 or T4). Histologically, most grew predominantly as solid nests of basaloid cells exhibiting high mitotic rates and frequent necrosis, with histologic and immunohistochemical evidence of myoepithelial differentiation. Most cases also demonstrated foci of cribriform and/or tubular growth, along with an inconspicuous population of ducts. Thirty-four (69%) cases demonstrated an unusual pattern of surface involvement where markedly atypical squamous cells colonized tracts of the sinonasal mucosa. Less consistent histologic features included squamous differentiation within the invasive tumor (n=6), sarcomatoid transformation (n=5) including overt chondroid differentiation (n=3), and prominent epithelial-myoepithelial carcinoma-like growth (n=3). All cases were positive for p16 by immunostaining and HPV by RNA in situ hybridization. Thirty-three (67%) were positive for HPV 33. No cases tested for MYB, MYBL1, or NFIB gene fusions were positive. In the 38 cases with follow-up data, (mean follow-up, 42 mo) 14 recurred locally and 2 metastasized (lung, finger). There were no regional lymph node metastases, and no tumor-related deaths. HMSC is a distinct sinonasal neoplasm characterized by myoepithelial differentiation, frequent surface epithelial involvement, and the presence of high-risk HPV (especially type 33). Although it classically exhibits a cribriforming pattern that closely resembles adenoid cystic carcinoma, our expanded series highlights a histologic spectrum that is much broader than previously recognized, warranting a change in terminology. HMSC usually presents as a large and destructive sinonasal mass with high-grade histologic features, but it paradoxically behaves in a relatively indolent manner, underscoring the importance of distinguishing HMSC from true adenoid cystic carcinoma, squamous cell carcinoma, and other histologic mimickers.

Anaplastic variant of diffuse large B-cell lymphoma with hallmark cell appearance: Two cases highlighting a broad diversity in the diagnostics.

PubMed

Sakakibara, Ayako; Kohno, Kei; Kuroda, Naoto; Yorita, Kenji; Megahed, Nirmeen A; Eladl, Ahmed E; Daroontum, Teerada; Ishikawa, Eri; Suzuki, Yuka; Shimada, Satoko; Nakaguro, Masato; Shimoyama, Yoshie; Satou, Akira; Kato, Seiichi; Yatabe, Yasushi; Asano, Naoko; Nakamura, Shigeo

2018-04-01

The anaplastic variant of diffuse large B-cell lymphoma (A-DLBCL) is morphologically defined but remains an enigmatic disease in its clinicopathologic distinctiveness. Here, we report two cases involving Japanese women aged 59 years, both with A-DLBCL with the hallmark cell appearance and both indistinguishable from common and giant cell-rich patterns, respectively, of anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma. Case 1 was immunohistochemically positive for CD20, CD79a and OCT-2 but not for the other pan-B-cell markers, CD30 and ALK. Case 2 showed CD20 and CD30 positivity for 50% and 20% of tumor cells in addition to strong expression of p53 and MYC. Both were positive for fascin without Epstein-Barr virus association. Our cases provide additional support for the earlier reports that A-DLBCL exhibits clinicopathologic features distinct from ordinal diffuse large B-cell lymphoma (DLBCL), and documented its broader morphologic diversity than previously recognized. They also shed light on the unique feature of absent expression of pan-B-cell markers except for CD20 and CD79a, suggesting that A-DLBCL may biologically mimic a gray zone or intermediate lymphoma between DLBCL and classic Hodgkin lymphoma. © 2018 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

Substrate Topography Induces a Crossover from 2D to 3D Behavior in Fibroblast Migration

PubMed Central

Ghibaudo, Marion; Trichet, Léa; Le Digabel, Jimmy; Richert, Alain; Hersen, Pascal; Ladoux, Benoît

2009-01-01

Abstract In a three-dimensional environment, cells migrate through complex topographical features. Using microstructured substrates, we investigate the role of substrate topography in cell adhesion and migration. To do so, fibroblasts are plated on chemically identical substrates composed of microfabricated pillars. When the dimensions of the pillars (i.e., the diameter, length, and spacing) are varied, migrating cells encounter alternating flat and rough surfaces that depend on the spacing between the pillars. Consequently, we show that substrate topography affects cell shape and migration by modifying cell-to-substrate interactions. Cells on micropillar substrates exhibit more elongated and branched shapes with fewer actin stress fibers compared with cells on flat surfaces. By analyzing the migration paths in various environments, we observe different mechanisms of cell migration, including a persistent type of migration, that depend on the organization of the topographical features. These responses can be attributed to a spatial reorganization of the actin cytoskeleton due to physical constraints and a preferential formation of focal adhesions on the micropillars, with an increased lifetime compared to that observed on flat surfaces. By changing myosin II activity, we show that actomyosin contractility is essential in the cellular response to micron-scale topographic signals. Finally, the analysis of cell movements at the frontier between flat and micropillar substrates shows that cell transmigration through the micropillar substrates depends on the spacing between the pillars. PMID:19580774

Ultrastructural characterisation of the olfactory mucosa of the armadillo Dasypus hybridus (Dasypodidae, Xenarthra)

PubMed Central

FERRARI, C. C.; CARMANCHAHI, P. D.; ALDANA MARCOS, H. J.; AFFANNI, J. M.

2000-01-01

The ultrastructure of the olfactory mucosa of the armadillo Dasypus hybridus was studied. A comparison with the olfactory mucosa of another armadillo (Chaetophractus villosus) was made. The olfactory mucosa of D. hybridus shows many features which are similar to those of other mammals. Interestingly, it differs from the olfactory mucosa of the armadillo C. villosus. A suggestion is made that these differences may be due to differences in the digging habits of these species. In Dasypus, the supporting cells (SCs) showed dense vacuoles, multivesicular bodies and lysosome-like bodies probably related with the endocytotic system. The SCs show a dense network of SER presumably associated with xenobiotic mechanisms. The olfactory receptor neurons exhibit lysosome-like bodies and multivesicular bodies in their perikarya. These organelles suggest the presence of an endocytotic system. Duct cells of Bowman's glands exhibit secretory activities. Bowman's glands are compound-branched tubulo-acinar mixed glands with merocrine secretory mechanisms. PMID:10739023

Metabolic Dysregulation in Amyotrophic Lateral Sclerosis: Challenges and Opportunities

PubMed Central

Joardar, Archi; Manzo, Ernesto

2017-01-01

Purpose of Review Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease for which there is no cure and treatments are at best palliative. Several genes have been linked to ALS, which highlight defects in multiple cellular processes including RNA processing, proteostasis and metabolism. Clinical observations have identified glucose intolerance and dyslipidemia as key features of ALS however the causes of these metabolic alterations remain elusive. Recent Findings Recent studies reveal that motor neurons and muscle cells may undergo cell type specific metabolic changes that lead to utilization of alternate fuels. For example, ALS patients’ muscles exhibit reduced glycolysis and increased reliance on fatty acids. In contrast, ALS motor neurons contain damaged mitochondria and exhibit impaired lipid beta oxidation, potentially leading to increased glycolysis as a compensatory mechanism. Summary These findings highlight the complexities of metabolic alterations in ALS and provide new opportunities for designing therapeutic strategies based on restoring cellular energetics. PMID:29057168

Metabolic Dysregulation in Amyotrophic Lateral Sclerosis: Challenges and Opportunities.

PubMed

Joardar, Archi; Manzo, Ernesto; Zarnescu, Daniela C

2017-06-01

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease for which there is no cure and treatments are at best palliative. Several genes have been linked to ALS, which highlight defects in multiple cellular processes including RNA processing, proteostasis and metabolism. Clinical observations have identified glucose intolerance and dyslipidemia as key features of ALS however the causes of these metabolic alterations remain elusive. Recent studies reveal that motor neurons and muscle cells may undergo cell type specific metabolic changes that lead to utilization of alternate fuels. For example, ALS patients' muscles exhibit reduced glycolysis and increased reliance on fatty acids. In contrast, ALS motor neurons contain damaged mitochondria and exhibit impaired lipid beta oxidation, potentially leading to increased glycolysis as a compensatory mechanism. These findings highlight the complexities of metabolic alterations in ALS and provide new opportunities for designing therapeutic strategies based on restoring cellular energetics.

Droplet-based microtumor model to assess cell-ECM interactions and drug resistance of gastric cancer cells.

PubMed

Jang, Minjeong; Koh, Ilkyoo; Lee, Seok Jae; Cheong, Jae-Ho; Kim, Pilnam

2017-01-27

Gastric cancer (GC) is a common aggressive malignant tumor with high incidence and mortality worldwide. GC is classified into intestinal and diffuse types according to the histo-morphological features. Because of distinctly different clinico-pathological features, new cancer therapy strategies and in vitro preclinical models for the two pathological variants of GC is necessary. Since extracellular matrix (ECM) influence the biological behavior of tumor cells, we hypothesized that GC might be more similarly modeled in 3D with matrix rather than in 2D. Herein, we developed a microfluidic-based a three-dimensional (3D) in vitro gastric cancer model, with subsequent drug resistance assay. AGS (intestinal type) and Hs746T (diffuse type) gastric cancer cell lines were encapsulated in collagen beads with high cellular viability. AGS exhibited an aggregation pattern with expansive growth, whereas Hs746T showed single-cell-level infiltration. Importantly, in microtumor models, epithelial-mesenchymal transition (EMT) and metastatic genes were upregulated, whereas E-cadherin was downregulated. Expression of ß-catenin was decreased in drug-resistant cells, and chemosensitivity toward the anticancer drug (5-FU) was observed in microtumors. These results suggest that in vitro microtumor models may represent a biologically relevant platform for studying gastric cancer cell biology and tumorigenesis, and for accelerating the development of novel therapeutic targets.

Classification and clinical behavior of blastic plasmacytoid dendritic cell neoplasms according to their maturation-associated immunophenotypic profile

PubMed Central

Martín-Martín, Lourdes; López, Antonio; Vidriales, Belén; Caballero, María Dolores; Rodrigues, António Silva; Ferreira, Silvia Inês; Lima, Margarida; Almeida, Sérgio; Valverde, Berta; Martínez, Pilar; Ferrer, Ana; Candeias, Jorge; Ruíz-Cabello, Francisco; Buadesa, Josefa Marco; Sempere, Amparo; Villamor, Neus

2015-01-01

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare subtype of leukemia/lymphoma, whose diagnosis can be difficult to achieve due to its clinical and biological heterogeneity, as well as its overlapping features with other hematologic malignancies. In this study we investigated whether the association between the maturational stage of tumor cells and the clinico-biological and prognostic features of the disease, based on the analysis of 46 BPDCN cases classified into three maturation-associated subgroups on immunophenotypic grounds. Our results show that blasts from cases with an immature plasmacytoid dendritic cell (pDC) phenotype exhibit an uncommon CD56− phenotype, coexisting with CD34+ non-pDC tumor cells, typically in the absence of extramedullary (e.g. skin) disease at presentation. Conversely, patients with a more mature blast cell phenotype more frequently displayed skin/extramedullary involvement and spread into secondary lymphoid tissues. Despite the dismal outcome, acute lymphoblastic leukemia-type therapy (with central nervous system prophylaxis) and/or allogeneic stem cell transplantation appeared to be the only effective therapies. Overall, our findings indicate that the maturational profile of pDC blasts in BPDCN is highly heterogeneous and translates into a wide clinical spectrum -from acute leukemia to mature lymphoma-like behavior-, which may also lead to variable diagnosis and treatment. PMID:26056082

Bcl-2 and caspase-3 are major regulators in Agaricus blazei-induced human leukemic U937 cell apoptosis through dephoshorylation of Akt.

PubMed

Jin, Cheng-Yun; Moon, Dong-Oh; Choi, Yung Hyun; Lee, Jae-Dong; Kim, Gi-Young

2007-08-01

Agaricus blazei is a medicinal mushroom that possesses antimetastatic, antitumor, antimutagenic, and immunostimulating effects. However, the molecular mechanisms involved in A. blazei-mediated apoptosis remain unclear. In the present study, to elucidate the role of the Bcl-2 in A. blazei-mediated apoptosis, U937 cells were transfected with either empty vector (U937/vec) or vector containing cDNA encoding full-length Bcl-2 (U937/Bcl-2). As compared with U937/vec, U937/Bcl-2 cells exhibited a 4-fold greater expression of Bcl-2. Treatment of U937/vec with 1.0-4.0 mg/ml of A. blazei extract (ABE) for 24 h resulted in a significant induction of morphologic features indicative of apoptosis. In contrast, U937/Bcl-2 exposed to the same ABE treatment only exhibited a slight induction of apoptotic features. ABE-induced apoptosis was accompanied by downregulation of antiapoptotic proteins such as X-linked inhibitor of apoptosis protein (XIAP), inhibitor of apoptosis protein (cIAP)-2 and Bcl-2, activation of caspase-3, and cleavage of poly(ADP-ribose)polymerase (PARP). Ectopic expression of Bcl-2 was associated with significantly induced expression of antiapoptotic proteins, such as cIAP-2 and Bcl-2, but not XIAP. Ectopic expression of Bcl-2 also reduced caspase-3 activation and PARP cleavage in ABE treated U937 cells. Furthermore, treatment with the caspase-3 inhibitor z-DEVD-fmk was sufficient to restore cell viability following ABE treatment. This increase in viability was ascribed to downregulation of caspase-3 and blockage of PARP and PLC-gamma cleavage. ABE also triggered the downregulation of Akt, and combined treatment with LY294002 (an inhibitor of Akt) significantly decreased cell viability. The results indicated that major regulators of ABE-induced apoptosis in human leukemic U937 cells are Bcl-2 and caspase-3, which are associated with dephosphorylation of the Akt signal pathway.

Biomass digestibility is predominantly affected by three factors of wall polymer features distinctive in wheat accessions and rice mutants

PubMed Central

2013-01-01

Background Wheat and rice are important food crops with enormous biomass residues for biofuels. However, lignocellulosic recalcitrance becomes a crucial factor on biomass process. Plant cell walls greatly determine biomass recalcitrance, thus it is essential to identify their key factors on lignocellulose saccharification. Despite it has been reported about cell wall factors on biomass digestions, little is known in wheat and rice. In this study, we analyzed nine typical pairs of wheat and rice samples that exhibited distinct cell wall compositions, and identified three major factors of wall polymer features that affected biomass digestibility. Results Based on cell wall compositions, ten wheat accessions and three rice mutants were classified into three distinct groups each with three typical pairs. In terms of group I that displayed single wall polymer alternations in wheat, we found that three wall polymer levels (cellulose, hemicelluloses and lignin) each had a negative effect on biomass digestibility at similar rates under pretreatments of NaOH and H2SO4 with three concentrations. However, analysis of six pairs of wheat and rice samples in groups II and III that each exhibited a similar cell wall composition, indicated that three wall polymer levels were not the major factors on biomass saccharification. Furthermore, in-depth detection of the wall polymer features distinctive in rice mutants, demonstrated that biomass digestibility was remarkably affected either negatively by cellulose crystallinity (CrI) of raw biomass materials, or positively by both Ara substitution degree of non-KOH-extractable hemicelluloses (reverse Xyl/Ara) and p-coumaryl alcohol relative proportion of KOH-extractable lignin (H/G). Correlation analysis indicated that Ara substitution degree and H/G ratio negatively affected cellulose crystallinity for high biomass enzymatic digestion. It was also suggested to determine whether Ara and H monomer have an interlinking with cellulose chains in the future. Conclusions Using nine typical pairs of wheat and rice samples having distinct cell wall compositions and wide biomass saccharification, Ara substitution degree and monolignin H proportion have been revealed to be the dominant factors positively determining biomass digestibility upon various chemical pretreatments. The results demonstrated the potential of genetic modification of plant cell walls for high biomass saccharification in bioenergy crops. PMID:24341349

From stem cell to embryo without centrioles.

PubMed

Stevens, Naomi R; Raposo, Alexandre A S F; Basto, Renata; St Johnston, Daniel; Raff, Jordan W

2007-09-04

Centrosome asymmetry plays a key role in ensuring the asymmetric division of Drosophila neural stem cells (neuroblasts [NBs]) and male germline stem cells (GSCs) [1-3]. In both cases, one centrosome is anchored close to a specific cortical region during interphase, thus defining the orientation of the spindle during the ensuing mitosis. To test whether asymmetric centrosome behavior is a general feature of stem cells, we have studied female GSCs, which divide asymmetrically, producing another GSC and a cystoblast. The cystoblast then divides and matures into an oocyte, a process in which centrosomes exhibit a series of complex behaviors proposed to play a crucial role in oogenesis [4-6]. We show that the interphase centrosome does not define spindle orientation in female GSCs and that DSas-4 mutant GSCs [7], lacking centrioles and centrosomes, invariably divide asymmetrically to produce cystoblasts that proceed normally through oogenesis-remarkably, oocyte specification, microtubule organization, and mRNA localization are all unperturbed. Mature oocytes can be fertilized, but embryos that cannot support centriole replication arrest very early in development. Thus, centrosomes are dispensable for oogenesis but essential for early embryogenesis. These results reveal that asymmetric centrosome behavior is not an essential feature of stem cell divisions.

Morphological changes in human neural cells following tick-borne encephalitis virus infection.

PubMed

Růzek, Daniel; Vancová, Marie; Tesarová, Martina; Ahantarig, Arunee; Kopecký, Jan; Grubhoffer, Libor

2009-07-01

Tick-borne encephalitis (TBE) is one of the leading and most dangerous human viral neuroinfections in Europe and north-eastern Asia. The clinical manifestations include asymptomatic infections, fevers and debilitating encephalitis that might progress into chronic disease or fatal infection. To understand TBE pathology further in host nervous systems, three human neural cell lines, neuroblastoma, medulloblastoma and glioblastoma, were infected with TBE virus (TBEV). The susceptibility and virus-mediated cytopathic effect, including ultrastructural and apoptotic changes of the cells, were examined. All the neural cell lines tested were susceptible to TBEV infection. Interestingly, the neural cells produced about 100- to 10,000-fold higher virus titres than the conventional cell lines of extraneural origin, indicating the highly susceptible nature of neural cells to TBEV infection. The infection of medulloblastoma and glioblastoma cells was associated with a number of major morphological changes, including proliferation of membranes of the rough endoplasmic reticulum and extensive rearrangement of cytoskeletal structures. The TBEV-infected cells exhibited either necrotic or apoptotic morphological features. We observed ultrastructural apoptotic signs (condensation, margination and fragmentation of chromatin) and other alterations, such as vacuolation of the cytoplasm, dilatation of the endoplasmic reticulum cisternae and shrinkage of cells, accompanied by a high density of the cytoplasm. On the other hand, infected neuroblastoma cells did not exhibit proliferation of membranous structures. The virions were present in both the endoplasmic reticulum and the cytoplasm. Cells were dying preferentially by necrotic mechanisms rather than apoptosis. The neuropathological significance of these observations is discussed.

Evaluation of supercapacitors for space applications under thermal vacuum conditions

NASA Astrophysics Data System (ADS)

Chin, Keith C.; Green, Nelson W.; Brandon, Erik J.

2018-03-01

Commercially available supercapacitor cells from three separate vendors were evaluated for use in a space environment using thermal vacuum (Tvac) testing. Standard commercial cells are not hermetically sealed, but feature crimp or double seam seals between the header and the can, which may not maintain an adequate seal under vacuum. Cells were placed in a small vacuum chamber, and cycled between three separate temperature set points. Charging and discharging of cells was executed following each temperature soak, to confirm there was no significant impact on performance. A final electrical performance check, visual inspection and mass check following testing were also performed, to confirm the integrity of the cells had not been compromised during exposure to thermal cycling under vacuum. All cells tested were found to survive this testing protocol and exhibited no significant impact on electrical performance.

Diagnosis of Diabetes Mellitus by Extraction of Morphological Features of Red Blood Cells Using an Artificial Neural Network.

PubMed

Palanisamy, Vinupritha; Mariamichael, Anburajan

2016-10-01

Background and Aim: Diabetes mellitus is a metabolic disorder characterized by varying hyperglycemias either due to insufficient secretion of insulin by the pancreas or improper utilization of glucose. The study was aimed to investigate the association of morphological features of erythrocytes among normal and diabetic subjects and its gender-based changes and thereby to develop a computer aided tool to diagnose diabetes using features extracted from RBC. Materials and Methods: The study involved 138 normal and 144 diabetic subjects. The blood was drawn from the subjects and the blood smear prepared was digitized using Zeiss fluorescent microscope. The digitized images were pre-processed and texture segmentation was performed to extract the various morphological features. The Pearson correlation test was performed and subsequently, classification of subjects as normal and diabetes was carried out by a neural network classifier based on the features that demonstrated significance at the level of P <0.05. Result: The proposed system demonstrated an overall accuracy, sensitivity, specificity, positive predictive value and negative predictive value of 93.3, 93.71, 92.8, 93.1 and 93.5% respectively. Conclusion: The morphological features exhibited a statistically significant difference (P<0.01) between the normal and diabetic cells, suggesting that it could be helpful in the diagnosis of Diabetes mellitus using a computer aided system. © Georg Thieme Verlag KG Stuttgart · New York.

Extracellular redox state regulates features associated with prostate cancer cell invasion.

PubMed

Chaiswing, Luksana; Zhong, Weixiong; Cullen, Joseph J; Oberley, Larry W; Oberley, Terry D

2008-07-15

We have examined the possible role of extracellular reduction-oxidation (redox) state in regulation of biological/biochemical features associated with prostate cancer cell invasion. DU145, PC-3, and RWPE1-derived human prostate cancer (WPE1-NB26) cell lines were used for the present in vitro analysis. Increasing levels of nitric oxide using S-nitroso-N-acetylpenicillamine resulted in a decrease in cell invasion ability, whereas increasing levels of extracellular superoxide radical (O(2)(*-)) using xanthine/xanthine oxidase resulted in an increase in cell invasion ability in these three cell lines. WPE1-NB26 cells exhibited an increased glutathione/glutathione disulfide ratio in the medium in comparison with RWPE1 cells (immortalized but nonmalignant prostate epithelial cells), suggesting an alteration of extracellular redox state of WPE1-NB26 cells. We hypothesized that O(2)(*-) production at or near the plasma membrane or in the adjacent extracellular matrix at least partially regulated prostate cancer cell invasion. Using adenovirus-mediated extracellular superoxide dismutase (EC-SOD) gene transduction to enzymatically decrease O(2)(*-) levels, we showed that in the presence of heparin, adenovirus EC-SOD gene transduction resulted in an increase in the expression of EC-SOD outside the cells with resultant inhibition of cell invasion ability. This inhibition correlated with reduced metalloproteinase [matrix metalloproteinase (MMP) 2/membrane type 1-MMP] activities and increased levels of extracellular nitrite. Our results suggest a prominent role of extracellular redox status in regulation of cell invasion, which may provide opportunities for therapeutic interventions.

Biallelic Alteration and Dysregulation of the Hippo Pathway in Mucinous Tubular and Spindle Cell Carcinoma of the Kidney.

PubMed

Mehra, Rohit; Vats, Pankaj; Cieslik, Marcin; Cao, Xuhong; Su, Fengyun; Shukla, Sudhanshu; Udager, Aaron M; Wang, Rui; Pan, Jincheng; Kasaian, Katayoon; Lonigro, Robert; Siddiqui, Javed; Premkumar, Kumpati; Palapattu, Ganesh; Weizer, Alon; Hafez, Khaled S; Wolf, J Stuart; Sangoi, Ankur R; Trpkov, Kiril; Osunkoya, Adeboye O; Zhou, Ming; Giannico, Giovanna; McKenney, Jesse K; Dhanasekaran, Saravana M; Chinnaiyan, Arul M

2016-11-01

Mucinous tubular and spindle cell carcinoma (MTSCC) is a relatively rare subtype of renal cell carcinoma (RCC) with distinctive morphologic and cytogenetic features. Here, we carry out whole-exome and transcriptome sequencing of a multi-institutional cohort of MTSCC (n = 22). We demonstrate the presence of either biallelic loss of Hippo pathway tumor suppressor genes (TSG) and/or evidence of alteration of Hippo pathway genes in 85% of samples. PTPN14 (31%) and NF2 (22%) were the most commonly implicated Hippo pathway genes, whereas other genes such as SAV1 and HIPK2 were also involved in a mutually exclusive fashion. Mutations in the context of recurrent chromosomal losses amounted to biallelic alterations in these TSGs. As a readout of Hippo pathway inactivation, a majority of cases (90%) exhibited increased nuclear YAP1 protein expression. Taken together, nearly all cases of MTSCC exhibit some evidence of Hippo pathway dysregulation. MTSCC is a rare and relatively recently described subtype of RCC. Next-generation sequencing of a multi-institutional MTSCC cohort revealed recurrent chromosomal losses and somatic mutations in the Hippo signaling pathway genes leading to potential YAP1 activation. In virtually all cases of MTSCC, there was evidence of Hippo pathway dysregulation, suggesting a common mechanistic basis for this disease. Cancer Discov; 6(11); 1258-66. ©2016 AACR.This article is highlighted in the In This Issue feature, p. 1197. ©2016 American Association for Cancer Research.

Cerebral organoids derived from Sandhoff disease-induced pluripotent stem cells exhibit impaired neurodifferentiation[S

PubMed Central

Allende, Maria L.; Cook, Emily K.; Larman, Bridget C.; Nugent, Adrienne; Brady, Jacqueline M.; Golebiowski, Diane; Sena-Esteves, Miguel; Tifft, Cynthia J.

2018-01-01

Sandhoff disease, one of the GM2 gangliosidoses, is a lysosomal storage disorder characterized by the absence of β-hexosaminidase A and B activity and the concomitant lysosomal accumulation of its substrate, GM2 ganglioside. It features catastrophic neurodegeneration and death in early childhood. How the lysosomal accumulation of ganglioside might affect the early development of the nervous system is not understood. Recently, cerebral organoids derived from induced pluripotent stem (iPS) cells have illuminated early developmental events altered by disease processes. To develop an early neurodevelopmental model of Sandhoff disease, we first generated iPS cells from the fibroblasts of an infantile Sandhoff disease patient, then corrected one of the mutant HEXB alleles in those iPS cells using CRISPR/Cas9 genome-editing technology, thereby creating isogenic controls. Next, we used the parental Sandhoff disease iPS cells and isogenic HEXB-corrected iPS cell clones to generate cerebral organoids that modeled the first trimester of neurodevelopment. The Sandhoff disease organoids, but not the HEXB-corrected organoids, accumulated GM2 ganglioside and exhibited increased size and cellular proliferation compared with the HEXB-corrected organoids. Whole-transcriptome analysis demonstrated that development was impaired in the Sandhoff disease organoids, suggesting that alterations in neuronal differentiation may occur during early development in the GM2 gangliosidoses. PMID:29358305

How do generalized jamming transitions affect collective migration in confluent tissues?

NASA Astrophysics Data System (ADS)

Manning, M. Lisa

Recent experiments have demonstrated that tissues involved in embryonic development, lung function, wound healing, and cancer progression are close to fluid-to-solid, or ``jamming'' transitions. Theoretical models for confluent 2D tissues have also been shown to exhibit continuous rigidity transitions. However, in vivobiological systems can differ in significant ways from the simple 2D models. For example, many tissues are three-dimensional, mechanically heterogeneous, and/or composed of mechanosensitive cells interspersed with extracellular matrix. We have extended existing models for confluent tissues to capture these features, and we find interesting predictions for collective cell motion that are ultimately related to an underlying generalized jamming transition. For example, in 2D, we find that heterogeneous mixtures of cells spontaneously self-organize into rigid regions of stiffer cells interspersed with string-like groups of soft cells, reminiscent of cellular streaming seen in cancer. We also find that alignment interactions (of the sort often explored in self-propelled particle models) alter the transition and generate interesting flocked liquid and flocked solid collective migration patterns. Our model predicts that 3D tissues also exhibit a jamming transition governed by cell shape, as well as history-dependent aging, and we are currently exploring whether ECM-like interactions in 3D models might help explain compressional stiffening seen in experiments on human tissue.

Cerebral organoids derived from Sandhoff disease-induced pluripotent stem cells exhibit impaired neurodifferentiation.

PubMed

Allende, Maria L; Cook, Emily K; Larman, Bridget C; Nugent, Adrienne; Brady, Jacqueline M; Golebiowski, Diane; Sena-Esteves, Miguel; Tifft, Cynthia J; Proia, Richard L

2018-03-01

Sandhoff disease, one of the GM2 gangliosidoses, is a lysosomal storage disorder characterized by the absence of β-hexosaminidase A and B activity and the concomitant lysosomal accumulation of its substrate, GM2 ganglioside. It features catastrophic neurodegeneration and death in early childhood. How the lysosomal accumulation of ganglioside might affect the early development of the nervous system is not understood. Recently, cerebral organoids derived from induced pluripotent stem (iPS) cells have illuminated early developmental events altered by disease processes. To develop an early neurodevelopmental model of Sandhoff disease, we first generated iPS cells from the fibroblasts of an infantile Sandhoff disease patient, then corrected one of the mutant HEXB alleles in those iPS cells using CRISPR/Cas9 genome-editing technology, thereby creating isogenic controls. Next, we used the parental Sandhoff disease iPS cells and isogenic HEXB -corrected iPS cell clones to generate cerebral organoids that modeled the first trimester of neurodevelopment. The Sandhoff disease organoids, but not the HEXB -corrected organoids, accumulated GM2 ganglioside and exhibited increased size and cellular proliferation compared with the HEXB -corrected organoids. Whole-transcriptome analysis demonstrated that development was impaired in the Sandhoff disease organoids, suggesting that alterations in neuronal differentiation may occur during early development in the GM2 gangliosidoses.

Loss of the Cyclin-Dependent Kinase Inhibitor 1 in the Context of Brachyury-Mediated Phenotypic Plasticity Drives Tumor Resistance to Immune Attack.

PubMed

Hamilton, Duane H; McCampbell, Kristen K; Palena, Claudia

2018-01-01

The acquisition of mesenchymal features by carcinoma cells is now recognized as a driver of metastasis and tumor resistance to a range of anticancer therapeutics, including chemotherapy, radiation, and certain small-molecule targeted therapies. With the recent successful implementation of immunotherapies for the treatment of various types of cancer, there is growing interest in understanding whether an immunological approach could be effective at eradicating carcinoma cells bearing mesenchymal features. Recent studies, however, demonstrated that carcinoma cells that have acquired mesenchymal features may also exhibit decreased susceptibility to lysis mediated by immune effector cells, including antigen-specific CD8 + T cells, innate natural killer (NK), and lymphokine-activated killer (LAK) cells. Here, we investigated the mechanism involved in the immune resistance of carcinoma cells that express very high levels of the transcription factor brachyury, a molecule previously shown to drive the acquisition of mesenchymal features by carcinoma cells. Our results demonstrate that very high levels of brachyury expression drive the loss of the cyclin-dependent kinase inhibitor 1 (p21CIP1, p21), an event that results in decreased tumor susceptibility to immune-mediated lysis. We show here that reconstitution of p21 expression markedly increases the lysis of brachyury-high tumor cells mediated by antigen-specific CD8 + T cells, NK, and LAK cells, TNF-related apoptosis-inducing ligand, and chemotherapy. Several reports have now demonstrated a role for p21 loss in cancer as an inducer of the epithelial-mesenchymal transition. The results from the present study situate p21 as a central player in many of the aspects of the phenomenon of brachyury-mediated mesenchymalization of carcinomas, including resistance to chemotherapy and immune-mediated cytotoxicity. We also demonstrate here that the defects in tumor cell death described in association with very high levels of brachyury could be alleviated via the use of a WEE1 inhibitor. Several vaccine platforms targeting brachyury have been developed and are undergoing clinical evaluation. These studies provide further rationale for the use of WEE1 inhibition in combination with brachyury-based immunotherapeutic approaches.

Loss of the Cyclin-Dependent Kinase Inhibitor 1 in the Context of Brachyury-Mediated Phenotypic Plasticity Drives Tumor Resistance to Immune Attack

PubMed Central

Hamilton, Duane H.; McCampbell, Kristen K.; Palena, Claudia

2018-01-01

The acquisition of mesenchymal features by carcinoma cells is now recognized as a driver of metastasis and tumor resistance to a range of anticancer therapeutics, including chemotherapy, radiation, and certain small-molecule targeted therapies. With the recent successful implementation of immunotherapies for the treatment of various types of cancer, there is growing interest in understanding whether an immunological approach could be effective at eradicating carcinoma cells bearing mesenchymal features. Recent studies, however, demonstrated that carcinoma cells that have acquired mesenchymal features may also exhibit decreased susceptibility to lysis mediated by immune effector cells, including antigen-specific CD8+ T cells, innate natural killer (NK), and lymphokine-activated killer (LAK) cells. Here, we investigated the mechanism involved in the immune resistance of carcinoma cells that express very high levels of the transcription factor brachyury, a molecule previously shown to drive the acquisition of mesenchymal features by carcinoma cells. Our results demonstrate that very high levels of brachyury expression drive the loss of the cyclin-dependent kinase inhibitor 1 (p21CIP1, p21), an event that results in decreased tumor susceptibility to immune-mediated lysis. We show here that reconstitution of p21 expression markedly increases the lysis of brachyury-high tumor cells mediated by antigen-specific CD8+ T cells, NK, and LAK cells, TNF-related apoptosis-inducing ligand, and chemotherapy. Several reports have now demonstrated a role for p21 loss in cancer as an inducer of the epithelial–mesenchymal transition. The results from the present study situate p21 as a central player in many of the aspects of the phenomenon of brachyury-mediated mesenchymalization of carcinomas, including resistance to chemotherapy and immune-mediated cytotoxicity. We also demonstrate here that the defects in tumor cell death described in association with very high levels of brachyury could be alleviated via the use of a WEE1 inhibitor. Several vaccine platforms targeting brachyury have been developed and are undergoing clinical evaluation. These studies provide further rationale for the use of WEE1 inhibition in combination with brachyury-based immunotherapeutic approaches. PMID:29774202

Photonic crystal geometry for organic solar cells.

PubMed

Ko, Doo-Hyun; Tumbleston, John R; Zhang, Lei; Williams, Stuart; DeSimone, Joseph M; Lopez, Rene; Samulski, Edward T

2009-07-01

We report organic solar cells with a photonic crystal nanostructure embossed in the photoactive bulk heterojunction layer, a topography that exhibits a 3-fold enhancement of the absorption in specific regions of the solar spectrum in part through multiple excitation resonances. The photonic crystal geometry is fabricated using a materials-agnostic process called PRINT wherein highly ordered arrays of nanoscale features are readily made in a single processing step over wide areas (approximately 4 cm(2)) that is scalable. We show efficiency improvements of approximately 70% that result not only from greater absorption, but also from electrical enhancements. The methodology is generally applicable to organic solar cells and the experimental findings reported in our manuscript corroborate theoretical expectations.

Composite Solid Electrolyte For Lithium Cells

NASA Technical Reports Server (NTRS)

Peled, Emmanuel; Nagasubramanian, Ganesan; Halpert, Gerald; Attia, Alan I.

1994-01-01

Composite solid electrolyte material consists of very small particles, each coated with thin layer of Lil, bonded together with polymer electrolyte or other organic binder. Material offers significant advantages over other solid electrolytes in lithium cells and batteries. Features include high ionic conductivity and strength. Composite solid electrolyte expected to exhibit flexibility of polymeric electrolytes. Polymer in composite solid electrolyte serves two purposes: used as binder alone, conduction taking place only in AI2O3 particles coated with solid Lil; or used as both binder and polymeric electrolyte, providing ionic conductivity between solid particles that it binds together.

A possible radiation-resistant solar cell geometry using superlattices

NASA Technical Reports Server (NTRS)

Goradia, C.; Clark, R.; Brinker, D.

1985-01-01

A solar cell structure is proposed which uses a GaAs nipi doping superlattice. An important feature of this structure is that photogenerated minority carriers are very quickly collected in a time shorter than bulk lifetime in the fairly heavily doped n and p layers and these carriers are then transported parallel to the superlattice layers to selective ohmic contacts. Assuming that these already-separated carriers have very long recombination lifetimes, due to their across an indirect bandgap in real space, it is argued that the proposed structure may exhibit superior radiation tolerance along with reasonably high beginning-of-life efficiency.

Lineage-Specific Restraint of Pituitary Gonadotroph Cell Adenoma Growth

PubMed Central

Chesnokova, Vera; Zonis, Svetlana; Zhou, Cuiqi; Ben-Shlomo, Anat; Wawrowsky, Kolja; Toledano, Yoel; Tong, Yunguang; Kovacs, Kalman; Scheithauer, Bernd; Melmed, Shlomo

2011-01-01

Although pituitary adenomas are usually benign, unique trophic mechanisms restraining cell proliferation are unclear. As GH-secreting adenomas are associated with p53/p21-dependent senescence, we tested mechanisms constraining non-functioning pituitary adenoma growth. Thirty six gonadotroph-derived non-functioning pituitary adenomas all exhibited DNA damage, but undetectable p21 expression. However, these adenomas all expressed p16, and >90% abundantly expressed cytoplasmic clusterin associated with induction of the Cdk inhibitor p15 in 70% of gonadotroph and in 26% of somatotroph lineage adenomas (p = 0.006). Murine LβT2 and αT3 gonadotroph pituitary cells, and αGSU.PTTG transgenic mice with targeted gonadotroph cell adenomas also abundantly expressed clusterin and exhibited features of oncogene-induced senescence as evidenced by C/EBPβ and C/EBPδ induction. In turn, C/EBPs activated the clusterin promoter ∼5 fold, and elevated clusterin subsequently elicited p15 and p16 expression, acting to arrest murine gonadotroph cell proliferation. In contrast, specific clusterin suppression by RNAis enhanced gonadotroph proliferation. FOXL2, a tissue-specific gonadotroph lineage factor, also induced the clusterin promoter ∼3 fold in αT3 pituitary cells. As nine of 12 pituitary carcinomas were devoid of clusterin expression, this protein may limit proliferation of benign adenomatous pituitary cells. These results point to lineage-specific pathways restricting uncontrolled murine and human pituitary gonadotroph adenoma cell growth. PMID:21464964

6-Shogaol induces caspase-independent paraptosis in cancer cells via proteasomal inhibition.

PubMed

Nedungadi, Divya; Binoy, Anupama; Pandurangan, Nanjan; Pal, Sanjay; Nair, Bipin G; Mishra, Nandita

2018-03-15

An α, β-unsaturated carbonyl compound of ginger, 6-Shogaol (6S), induced extensive cytoplasmic vacuolation and cell death in breast cancer cell (MDA-MB-231) and non-small lung cancer (A549) cells. In the presence of autophagic inhibitors the cells continued to exhibit cytoplasmic vacuolation and cell death clearly distinguishing it from the classic autophagic process. 6S induced death did not exhibit the characteristic apoptotic features like caspase cleavage, phosphatidyl serine exposure and DNA fragmentation. The immunofluorescence with the Endoplasmic Reticulum (ER) resident protein, calreticulin indicated that the vacuoles were of ER origin, typical of paraptosis. This was supported by the increase in level of microtubule associated protein light chain 3B (LC3 I and LC3 II) and polyubiquitin binding protein, p62. The level of ER stress markers like polyubiquitinated proteins, Bip and CHOP also consistently increased. We have found that 6S inhibits the 26S proteasome. The proteasomal inhibitory activity was elucidated by a) molecular docking of 6S onto the active site of β5 subunit and b) reduced fluorescence by the fluorogenic substrate of the chymotrypsin-like subunit. In conclusion these studies demonstrate for the first time that proteasomal inhibition by 6S induces cell death via paraptosis. So 6-shogaol may act as a template for anti-cancer lead discovery against the apoptosis resistant cancer cells. Copyright © 2018 Elsevier Inc. All rights reserved.

Clonal B cells in Waldenström's macroglobulinemia exhibit functional features of chronic active B-cell receptor signaling

PubMed Central

Argyropoulos, K V; Vogel, R; Ziegler, C; Altan-Bonnet, G; Velardi, E; Calafiore, M; Dogan, A; Arcila, M; Patel, M; Knapp, K; Mallek, C; Hunter, Z R; Treon, S P; van den Brink, M R M; Palomba, M L

2016-01-01

Waldenström's macroglobulinemia (WM) is a B-cell non-Hodgkin's lymphoma (B-NHL) characterized by immunoglobulin M (IgM) monoclonal gammopathy and the medullary expansion of clonal lymphoplasmacytic cells. Neoplastic transformation has been partially attributed to hyperactive MYD88 signaling, secondary to the MYD88 L265P mutation, occurring in the majority of WM patients. Nevertheless, the presence of chronic active B-cell receptor (BCR) signaling, a feature of multiple IgM+ B-NHL, remains a subject of speculation in WM. Here, we interrogated the BCR signaling capacity of primary WM cells by utilizing multiparametric phosphoflow cytometry and found heightened basal phosphorylation of BCR-related signaling proteins, and augmented phosphoresponses on surface IgM (sIgM) crosslinking, compared with normal B cells. In support of those findings we observed high sIgM expression and loss of phosphatase activity in WM cells, which could both lead to signaling potentiation in clonal cells. Finally, led by the high-signaling heterogeneity among WM samples, we generated patient-specific phosphosignatures, which subclassified patients into a ‘high' and a ‘healthy-like' signaling group, with the second corresponding to patients with a more indolent clinical phenotype. These findings support the presence of chronic active BCR signaling in WM while providing a link between differential BCR signaling utilization and distinct clinical WM subgroups. PMID:26867669

Magnetic assembly of 3D cell clusters: visualizing the formation of an engineered tissue.

PubMed

Ghosh, S; Kumar, S R P; Puri, I K; Elankumaran, S

2016-02-01

Contactless magnetic assembly of cells into 3D clusters has been proposed as a novel means for 3D tissue culture that eliminates the need for artificial scaffolds. However, thus far its efficacy has only been studied by comparing expression levels of generic proteins. Here, it has been evaluated by visualizing the evolution of cell clusters assembled by magnetic forces, to examine their resemblance to in vivo tissues. Cells were labeled with magnetic nanoparticles, then assembled into 3D clusters using magnetic force. Scanning electron microscopy was used to image intercellular interactions and morphological features of the clusters. When cells were held together by magnetic forces for a single day, they formed intercellular contacts through extracellular fibers. These kept the clusters intact once the magnetic forces were removed, thus serving the primary function of scaffolds. The cells self-organized into constructs consistent with the corresponding tissues in vivo. Epithelial cells formed sheets while fibroblasts formed spheroids and exhibited position-dependent morphological heterogeneity. Cells on the periphery of a cluster were flattened while those within were spheroidal, a well-known characteristic of connective tissues in vivo. Cells assembled by magnetic forces presented visual features representative of their in vivo states but largely absent in monolayers. This established the efficacy of contactless assembly as a means to fabricate in vitro tissue models. © 2016 John Wiley & Sons Ltd.

Deletion of OTX2 in neural ectoderm delays anterior pituitary development

PubMed Central

Mortensen, Amanda H.; Schade, Vanessa; Lamonerie, Thomas; Camper, Sally A.

2015-01-01

OTX2 is a homeodomain transcription factor that is necessary for normal head development in mouse and man. Heterozygosity for loss-of-function alleles causes an incompletely penetrant, haploinsufficiency disorder. Affected individuals exhibit a spectrum of features that range from developmental defects in eye and/or pituitary development to acephaly. To investigate the mechanism underlying the pituitary defects, we used different cre lines to inactivate Otx2 in early head development and in the prospective anterior and posterior lobes. Mice homozygous for Otx2 deficiency in early head development and pituitary oral ectoderm exhibit craniofacial defects and pituitary gland dysmorphology, but normal pituitary cell specification. The morphological defects mimic those observed in humans and mice with OTX2 heterozygous mutations. Mice homozygous for Otx2 deficiency in the pituitary neural ectoderm exhibited altered patterning of gene expression and ablation of FGF signaling. The posterior pituitary lobe and stalk, which normally arise from neural ectoderm, were extremely hypoplastic. Otx2 expression was intact in Rathke's pouch, the precursor to the anterior lobe, but the anterior lobe was hypoplastic. The lack of FGF signaling from the neural ectoderm was sufficient to impair anterior lobe growth, but not the differentiation of hormone-producing cells. This study demonstrates that Otx2 expression in the neural ectoderm is important intrinsically for the development of the posterior lobe and pituitary stalk, and it has significant extrinsic effects on anterior pituitary growth. Otx2 expression early in head development is important for establishing normal craniofacial features including development of the brain, eyes and pituitary gland. PMID:25315894

Transient features in nanosecond pulsed electric fields differentially modulate mitochondria and viability.

PubMed

Beebe, Stephen J; Chen, Yeong-Jer; Sain, Nova M; Schoenbach, Karl H; Xiao, Shu

2012-01-01

It is hypothesized that high frequency components of nanosecond pulsed electric fields (nsPEFs), determined by transient pulse features, are important for maximizing electric field interactions with intracellular structures. For monopolar square wave pulses, these transient features are determined by the rapid rise and fall of the pulsed electric fields. To determine effects on mitochondria membranes and plasma membranes, N1-S1 hepatocellular carcinoma cells were exposed to single 600 ns pulses with varying electric fields (0-80 kV/cm) and short (15 ns) or long (150 ns) rise and fall times. Plasma membrane effects were evaluated using Fluo-4 to determine calcium influx, the only measurable source of increases in intracellular calcium. Mitochondria membrane effects were evaluated using tetramethylrhodamine ethyl ester (TMRE) to determine mitochondria membrane potentials (ΔΨm). Single pulses with short rise and fall times caused electric field-dependent increases in calcium influx, dissipation of ΔΨm and cell death. Pulses with long rise and fall times exhibited electric field-dependent increases in calcium influx, but diminished effects on dissipation of ΔΨm and viability. Results indicate that high frequency components have significant differential impact on mitochondria membranes, which determines cell death, but lesser variances on plasma membranes, which allows calcium influxes, a primary determinant for dissipation of ΔΨm and cell death.

Perivascular Epithelioid Cell Tumor of Gastrointestinal Tract

PubMed Central

Lu, Biyan; Wang, Chenliang; Zhang, Junxiao; Kuiper, Roland P.; Song, Minmin; Zhang, Xiaoli; Song, Shunxin; van Kessel, Ad Geurts; Iwamoto, Aikichi; Wang, Jianping; Liu, Huanliang

2015-01-01

Perivascular epithelioid cell tumors of gastrointestinal tract (GI PEComas) are exceedingly rare, with only a limited number of published reports worldwide. Given the scarcity of GI PEComas and their relatively short follow-up periods, our current knowledge of their biologic behavior, molecular genetic alterations, diagnostic criteria, and prognostic factors continues to be very limited. We present 2 cases of GI PEComas, one of which showed an aggressive histologic behavior that underwent multiple combined chemotherapies. We also review the available English-language medical literature on GI PEComas-not otherwise specified (PEComas-NOS) and discuss their clinicopathological and molecular genetic features. Pathologic analyses including histomorphologic, immunohistochemical, and ultrastructural studies were performed to evaluate the clinicopathological features of GI PEComas, their diagnosis, and differential diagnosis. Immunohistochemistry, semiquantitative reverse transcriptase polymerase chain reaction, and DNA sequencing assays were carried out to detect the potential molecular genetic alterations in our cases Microscopically, the tumors showed distinctive histologic features of PEComas-NOS, including fascicular or nested architecture, epithelioid or spindled cell type, and clear to eosinophilic cytoplasm. The tumor cells were immunohistochemically positive for melanocytic markers. Molecular pathological assays confirmed a PSF-TFE3 gene fusion in one of our cases. Furthermore, in this case microphthalmia-associated transcription factor and its downstream genes were found to exhibit elevated transcript levels. Knowledge about the molecular genetic alterations in GI PEComas is still limited and warrants further study. PMID:25621681

Hydrophobic chalcogenide fibers for cell-based bio-optical sensors

NASA Astrophysics Data System (ADS)

Lucas, Pierre; Riley, Mark R.; Solis, Michelle A.; Juncker, Christophe; Collier, Jayne; Boesewetter, Dianne E.

2005-03-01

Chalcogenide fibers are shown to exhibit a hydrophobic surface behavior which results in detection enhancement for organic species in aqueous solutions. We use these fibers to monitor the infrared signature of human lung cells and detect the presence of toxic agents in the cell surrounding media. The signal is collected using a fiber evanescent wave spectroscopy set up with live human cells acting as a sensitizer for detection of minute quantities of toxicant. A monolayer of human alveolar epithelial cells form strong attachment at the surface of the fiber sensing zone and live in contact with the fiber while their IR spectra is collected remotely. Biochemical change in the living cells are detected during exposure to toxic agents. Variations in the spectroscopic features of the cells are observed in different spectral regions. Finally, the toxicity of Te2As3Se5 fibers is investigated.

All-solid electrodes with mixed conductor matrix

DOEpatents

Huggins, Robert A.; Boukamp, Bernard A.

1984-01-01

Alkali metal based electrochemical cells offer a great deal of promise for applications in many areas such as electric vehicles and load leveling purposes in stationary power plants. Lithium is an attractive candidate as the electroactive species in such cells since lithium is very electropositive, abundant and light weight. One type of lithium-based cell utilizes a molten salt electrolyte and normally is operated at elevated temperatures. The subject invention provides an electrochemical cell in one embodiment of which lithium is the electroactive species. The cell comprises an electrolyte, a positive electrode, and a negative electrode, either or both of which is an all-solid, composite microstructural electrode containing both a reactant phase and a mixed ionic-electronic conducting phase. The cells of the subject invention exhibit improved kinetic features, current and power densities. Repeated charging and discharging of these cells can be accomplished without appreciable loss of capacity.

Molecular Analysis of Neutrophil Differentiation from Human Induced Pluripotent Stem Cells Delineates the Kinetics of Key Regulators of Hematopoiesis.

PubMed

Sweeney, Colin L; Teng, Ruifeng; Wang, Hongmei; Merling, Randall K; Lee, Janet; Choi, Uimook; Koontz, Sherry; Wright, Daniel G; Malech, Harry L

2016-06-01

In vitro generation of mature neutrophils from human induced pluripotent stem cells (iPSCs) requires hematopoietic progenitor development followed by myeloid differentiation. The purpose of our studies was to extensively characterize this process, focusing on the critical window of development between hemogenic endothelium, hematopoietic stem/progenitor cells (HSPCs), and myeloid commitment, to identify associated regulators and markers that might enable the stem cell field to improve the efficiency and efficacy of iPSC hematopoiesis. We utilized a four-stage differentiation protocol involving: embryoid body (EB) formation (stage-1); EB culture with hematopoietic cytokines (stage-2); HSPC expansion (stage-3); and neutrophil maturation (stage-4). CD34(+) CD45(-) putative hemogenic endothelial cells were observed in stage-3 cultures, and expressed VEGFR-2/Flk-1/KDR and VE-cadherin endothelial markers, GATA-2, AML1/RUNX1, and SCL/TAL1 transcription factors, and endothelial/HSPC-associated microRNAs miR-24, miR-125a-3p, miR-126/126*, and miR-155. Upon further culture, CD34(+) CD45(-) cells generated CD34(+) CD45(+) HSPCs that produced hematopoietic CFUs. Mid-stage-3 CD34(+) CD45(+) HSPCs exhibited increased expression of GATA-2, AML1/RUNX1, SCL/TAL1, C/EBPα, and PU.1 transcription factors, but exhibited decreased expression of HSPC-associated microRNAs, and failed to engraft in immune-deficient mice. Mid-stage-3 CD34(-) CD45(+) cells maintained PU.1 expression and exhibited increased expression of hematopoiesis-associated miR-142-3p/5p and a trend towards increased miR-223 expression, indicating myeloid commitment. By late Stage-4, increased CD15, CD16b, and C/EBPɛ expression were observed, with 25%-65% of cells exhibiting morphology and functions of mature neutrophils. These studies demonstrate that hematopoiesis and neutrophil differentiation from human iPSCs recapitulates many features of embryonic hematopoiesis and neutrophil production in marrow, but reveals unexpected molecular signatures that may serve as a guide for enhancing iPSC hematopoiesis. Stem Cells 2016;34:1513-1526. © 2016 AlphaMed Press.

Stabilization of gene expression and cell morphology after explant recycling during fin explant culture in goldfish.

PubMed

Chenais, Nathalie; Lareyre, Jean-Jacques; Le Bail, Pierre-Yves; Labbe, Catherine

2015-07-01

The development of fin primary cell cultures for in vitro cellular and physiological studies is hampered by slow cell outgrowth, low proliferation rate, poor viability, and sparse cell characterization. Here, we investigated whether the recycling of fresh explants after a first conventional culture could improve physiological stability and sustainability of the culture. The recycled explants were able to give a supplementary cell culture showing faster outgrowth, cleaner cell layers and higher net cell production. The cells exhibited a highly stabilized profile for marker gene expression including a low cytokeratin 49 (epithelial marker) and a high collagen 1a1 (mesenchymal marker) expression. Added to the cell spindle-shaped morphology, motility behavior, and actin organization, this suggests that the cells bore stable mesenchymal characteristics. This contrast with the time-evolving expression pattern observed in the control fresh explants during the first 2 weeks of culture: a sharp decrease in cytokeratin 49 expression was concomitant with a gradual increase in col1a1. We surmise that such loss of epithelial features for the benefit of mesenchymal ones was triggered by an epithelial to mesenchymal transition (EMT) process or by way of a progressive population replacement process. Overall, our findings provide a comprehensive characterization of this new primary culture model bearing mesenchymal features and whose stability over culture time makes those cells good candidates for cell reprogramming prior to nuclear transfer, in a context of fish genome preservation. Copyright © 2015 Elsevier Inc. All rights reserved.

Histologic differentiation of desmoplastic melanoma from cicatrices.

PubMed

Kaneishi, N K; Cockerell, C J

1998-04-01

Desmoplastic malignant melanoma (DMM) is a rare variant of melanoma that can be very difficult to diagnose correctly both clinically and histologically. The problem is compounded by the fact that many lesions persist at previous biopsy or excision sites so that scar tissue is often present admixed with or adjacent to the spindle cell neoplasm which may exhibit fibroblastic differentiation itself. In order to assess this problem, we compared and contrasted the histologic features of six DMM with 15 examples of cicatrices from various sources. Mature scars were readily differentiated from DMM by light microscopy. In contrast, immature scar and DMM had many features in common including hypercellularity, nodular lymphoid infiltrates, myxoid stroma, and atypical nuclei. The presence of a melanocytic proliferation within the epidermis above the dermal component, neurotropism, and S-100 and/or HMB-45 positivity of neoplastic cells were the only features that permitted reliable differentiation between the two. Clinical correlation and review of previous biopsy specimens are crucial in preventing a delayed diagnosis of DMM. Re-excision is advised in all questionable cases.

Signatures of nonlinearity in single cell noise-induced oscillations.

PubMed

Thomas, Philipp; Straube, Arthur V; Timmer, Jens; Fleck, Christian; Grima, Ramon

2013-10-21

A class of theoretical models seeks to explain rhythmic single cell data by postulating that they are generated by intrinsic noise in biochemical systems whose deterministic models exhibit only damped oscillations. The main features of such noise-induced oscillations are quantified by the power spectrum which measures the dependence of the oscillatory signal's power with frequency. In this paper we derive an approximate closed-form expression for the power spectrum of any monostable biochemical system close to a Hopf bifurcation, where noise-induced oscillations are most pronounced. Unlike the commonly used linear noise approximation which is valid in the macroscopic limit of large volumes, our theory is valid over a wide range of volumes and hence affords a more suitable description of single cell noise-induced oscillations. Our theory predicts that the spectra have three universal features: (i) a dominant peak at some frequency, (ii) a smaller peak at twice the frequency of the dominant peak and (iii) a peak at zero frequency. Of these, the linear noise approximation predicts only the first feature while the remaining two stem from the combination of intrinsic noise and nonlinearity in the law of mass action. The theoretical expressions are shown to accurately match the power spectra determined from stochastic simulations of mitotic and circadian oscillators. Furthermore it is shown how recently acquired single cell rhythmic fibroblast data displays all the features predicted by our theory and that the experimental spectrum is well described by our theory but not by the conventional linear noise approximation. © 2013 Elsevier Ltd. All rights reserved.

Promotion of chloroplast proliferation upon enhanced post-mitotic cell expansion in leaves.

PubMed

Kawade, Kensuke; Horiguchi, Gorou; Ishikawa, Naoko; Hirai, Masami Yokota; Tsukaya, Hirokazu

2013-09-28

Leaves are determinate organs; hence, precise control of cell proliferation and post-mitotic cell expansion is essential for their growth. A defect in cell proliferation often triggers enhanced post-mitotic cell expansion in leaves. This phenomenon is referred to as 'compensation'. Several lines of evidence from studies on compensation have shown that cell proliferation and post-mitotic cell expansion are coordinately regulated during leaf development. Therefore, compensation has attracted much attention to the mechanisms for leaf growth. However, our understanding of compensation at the subcellular level remains limited because studies of compensation have focused mainly on cellular-level phenotypes. Proper leaf growth requires quantitative control of subcellular components in association with cellular-level changes. To gain insight into the subcellular aspect of compensation, we investigated the well-known relationship between cell area and chloroplast number per cell in compensation-exhibiting lines, and asked whether chloroplast proliferation is modulated in response to the induction of compensation. We first established a convenient and reliable method for observation of chloroplasts in situ. Using this method, we analyzed Arabidopsis thaliana mutants fugu5 and angustifolia3 (an3), and a transgenic line KIP-RELATED PROTEIN2 overexpressor (KRP2 OE), which are known to exhibit typical features of compensation. We here showed that chloroplast number per cell increased in the subepidermal palisade tissue of these lines. We analyzed tetraploidized wild type, fugu5, an3 and KRP2 OE, and found that cell area itself, but not nuclear ploidy, is a key parameter that determines the activity of chloroplast proliferation. In particular, in the case of an3, we uncovered that promotion of chloroplast proliferation depends on the enhanced post-mitotic cell expansion. The expression levels of chloroplast proliferation-related genes are similar to or lower than that in the wild type during this process. This study demonstrates that chloroplast proliferation is promoted in compensation-exhibiting lines. This promotion of chloroplast proliferation takes place in response to cell-area increase in post-mitotic phase in an3. The expression of chloroplast proliferation-related genes were not promoted in compensation-exhibiting lines including an3, arguing that an as-yet-unknown mechanism is responsible for modulation of chloroplast proliferation in these lines.

Promotion of chloroplast proliferation upon enhanced post-mitotic cell expansion in leaves

PubMed Central

2013-01-01

Background Leaves are determinate organs; hence, precise control of cell proliferation and post-mitotic cell expansion is essential for their growth. A defect in cell proliferation often triggers enhanced post-mitotic cell expansion in leaves. This phenomenon is referred to as ‘compensation’. Several lines of evidence from studies on compensation have shown that cell proliferation and post-mitotic cell expansion are coordinately regulated during leaf development. Therefore, compensation has attracted much attention to the mechanisms for leaf growth. However, our understanding of compensation at the subcellular level remains limited because studies of compensation have focused mainly on cellular-level phenotypes. Proper leaf growth requires quantitative control of subcellular components in association with cellular-level changes. To gain insight into the subcellular aspect of compensation, we investigated the well-known relationship between cell area and chloroplast number per cell in compensation-exhibiting lines, and asked whether chloroplast proliferation is modulated in response to the induction of compensation. Results We first established a convenient and reliable method for observation of chloroplasts in situ. Using this method, we analyzed Arabidopsis thaliana mutants fugu5 and angustifolia3 (an3), and a transgenic line KIP-RELATED PROTEIN2 overexpressor (KRP2 OE), which are known to exhibit typical features of compensation. We here showed that chloroplast number per cell increased in the subepidermal palisade tissue of these lines. We analyzed tetraploidized wild type, fugu5, an3 and KRP2 OE, and found that cell area itself, but not nuclear ploidy, is a key parameter that determines the activity of chloroplast proliferation. In particular, in the case of an3, we uncovered that promotion of chloroplast proliferation depends on the enhanced post-mitotic cell expansion. The expression levels of chloroplast proliferation-related genes are similar to or lower than that in the wild type during this process. Conclusions This study demonstrates that chloroplast proliferation is promoted in compensation-exhibiting lines. This promotion of chloroplast proliferation takes place in response to cell-area increase in post-mitotic phase in an3. The expression of chloroplast proliferation-related genes were not promoted in compensation-exhibiting lines including an3, arguing that an as-yet-unknown mechanism is responsible for modulation of chloroplast proliferation in these lines. PMID:24074400

Influence of major structural features of tocopherols and tocotrienols on their omega-oxidation by tocopherol-omega-hydroxylase.

PubMed

Sontag, Timothy J; Parker, Robert S

2007-05-01

Human cytochrome P450 4F2 (CYP4F2) catalyzes the initial omega-hydroxylation reaction in the metabolism of tocopherols and tocotrienols to carboxychromanols and is, to date, the only enzyme shown to metabolize vitamin E. The objective of this study was to characterize this activity, particularly the influence of key features of tocochromanol substrate structure. The influence of the number and positions of methyl groups on the chromanol ring, and of stereochemistry and saturation of the side chain, were explored using HepG2 cultures and microsomal reaction systems. Human liver microsomes and microsomes selectively expressing recombinant human CYP4F2 exhibited substrate activity patterns similar to those of HepG2 cells. Although activity was strongly associated with substrate accumulation by cells or microsomes, substantial differences in specific activities between substrates remained under conditions of similar microsomal membrane substrate concentration. Methylation at C5 of the chromanol ring was associated with markedly low activity. Tocotrienols exhibited much higher Vmax values than their tocopherol counterparts. Side chain stereochemistry had no effect on omega-hydroxylation of alpha-tocopherol (alpha-TOH) by any system. Kinetic analysis of microsomal CYP4F2 activity revealed Michaelis-Menten kinetics for alpha-TOH but allosteric cooperativity for other vitamers, especially tocotrienols. Additionally, alpha-TOH was a positive effector of omega-hydroxylation of other vitamers. These results indicate that CYP4F2-mediated tocopherol-omega-hydroxylation is a central feature underlying the different biological half-lives, and therefore biopotencies, of the tocopherols and tocotrienols.

A Possible Phenomenon of Persistence in Pseudomonas aeruginosa Treated with Methylene Blue and Red Light.

PubMed

Forte Giacobone, Ana Florencia; Ruiz Gale, Maria Fernanda; Hogert, Elsa Noemí; Oppezzo, Oscar Juan

2016-09-01

Planktonic Pseudomonas aeruginosa cells harvested in stationary phase were exposed to red light in the presence of methylene blue to study the potential occurrence of persistence in bacterial populations submitted to photodynamic antimicrobial therapy. Survival curves revealed the existence of small subpopulations of cells exhibiting increased ability to tolerate the treatment. These subpopulations were detected even using high concentrations of photosensitizer, whether added in a single step or following a fractionated scheme, and when the irradiation medium was modified to delay the photodecomposition of methylene blue. When cells grown from survivors to the treatment were cultured and exposed to red light and dye, their responses were similar to that of the original strain. These results exclude exhaustion of the photosensitizer and selection of resistant mutants as explanations for the features of the survival curves. Cells able to tolerate the treatment were found even when radiation was imparted at a high-dose rate. They exhibit a response typical of persisters, which tolerate antimicrobial agents due to transient and reversible changes in their phenotype, suggesting that persistence is a factor to consider upon evaluating the efficacy of photodynamic antimicrobial therapy. © 2016 The American Society of Photobiology.

Water soluble nanoporous nanoparticle for in vivo targeted drug delivery and controlled release in B cells tumor context

NASA Astrophysics Data System (ADS)

de Angelis, F.; Pujia, A.; Falcone, C.; Iaccino, E.; Palmieri, C.; Liberale, C.; Mecarini, F.; Candeloro, P.; Luberto, L.; de Laurentiis, A.; Das, G.; Scala, G.; di Fabrizio, E.

2010-10-01

Multitasking nanoparticles are gaining great attention for smart drug delivery systems. The exploration of the nano-scale opens new concrete opportunities for revealing new properties and undiscovered cell-particle interactions. Here we present a biodegradable nanoporous silicon nanoparticle that can be successfully employed for in vivo targeted drug delivery and sustained release. The bare nanoporous nanocarriers can be accurately designed and fabricated with an effective control of porosity, surface chemistry and particle size, up to a few nm. The proposed nanoparticles exhibit several remarkable features including high payload, biodegradability, no toxicity, and multiple loading in water without the need of additional chemical reagents at room temperature. The targeting strategy is based on phage display technology that was successfully used to discover cell surface binding peptide for murine B lymphoma A20 cell line. The peptide used in combination with the nanoporous nanoparticles allows an efficient in vivo targeting, a sustained release and a sensible therapeutic effect.Multitasking nanoparticles are gaining great attention for smart drug delivery systems. The exploration of the nano-scale opens new concrete opportunities for revealing new properties and undiscovered cell-particle interactions. Here we present a biodegradable nanoporous silicon nanoparticle that can be successfully employed for in vivo targeted drug delivery and sustained release. The bare nanoporous nanocarriers can be accurately designed and fabricated with an effective control of porosity, surface chemistry and particle size, up to a few nm. The proposed nanoparticles exhibit several remarkable features including high payload, biodegradability, no toxicity, and multiple loading in water without the need of additional chemical reagents at room temperature. The targeting strategy is based on phage display technology that was successfully used to discover cell surface binding peptide for murine B lymphoma A20 cell line. The peptide used in combination with the nanoporous nanoparticles allows an efficient in vivo targeting, a sustained release and a sensible therapeutic effect. Electronic supplementary information (ESI) available: Nanoparticles fabrication; payload evaluation; dissolution and release profiles; multivalent loading; targeting specifity on A20 Cells; cell cycle analysis; in vitro cytotoxicity assay; in vivo cytotoxicity assay. See DOI: 10.1039/c0nr00161a

Traditional Aboriginal Preparation Alters the Chemical Profile of Carica papaya Leaves and Impacts on Cytotoxicity towards Human Squamous Cell Carcinoma.

PubMed

Nguyen, Thao T; Parat, Marie-Odile; Shaw, Paul N; Hewavitharana, Amitha K; Hodson, Mark P

2016-01-01

Carica papaya leaf decoction, an Australian Aboriginal remedy, has been used widely for its healing capabilities against cancer, with numerous anecdotal reports. In this study we investigated its in vitro cytotoxicity on human squamous cell carcinoma cells followed by metabolomic profiling of Carica papaya leaf decoction and leaf juice/brewed leaf juice to determine the effects imparted by the long heating process typical of the Aboriginal remedy preparation. MTT assay results showed that in comparison with the decoction, the leaf juice not only exhibited a stronger cytotoxic effect on SCC25 cancer cells, but also produced a significant cancer-selective effect as shown by tests on non-cancerous human keratinocyte HaCaT cells. Furthermore, evidence from testing brewed leaf juice on these two cell lines suggested that the brewing process markedly reduced the selective effect of Carica papaya leaf on SCC25 cancer cells. To tentatively identify the compounds that contribute to the distinct selective anticancer activity of leaf juice, an untargeted metabolomic approach employing Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry followed by multivariate data analysis was applied. Some 90 and 104 peaks in positive and negative mode respectively were selected as discriminatory features from the chemical profile of leaf juice and >1500 putative compound IDs were obtained via database searching. Direct comparison of chromatographic and tandem mass spectral data to available reference compounds confirmed one feature as a match with its proposed authentic standard, namely pheophorbide A. However, despite pheophorbide A exhibiting cytotoxic activity on SCC25 cancer cells, it did not prove to be the compound contributing principally to the selective activity of leaf juice. With promising results suggesting stronger and more selective anticancer effects when compared to the Aboriginal remedy, Carica papaya leaf juice warrants further study to explore its activity on other cancer cell lines, as well as investigation to confirm the identity of compounds contributing to its selective effect, particularly those compounds altered by the long heating process applied during the traditional Aboriginal remedy preparation.

Traditional Aboriginal Preparation Alters the Chemical Profile of Carica papaya Leaves and Impacts on Cytotoxicity towards Human Squamous Cell Carcinoma

PubMed Central

Nguyen, Thao T.; Parat, Marie-Odile; Shaw, Paul N.; Hewavitharana, Amitha K.; Hodson, Mark P.

2016-01-01

Carica papaya leaf decoction, an Australian Aboriginal remedy, has been used widely for its healing capabilities against cancer, with numerous anecdotal reports. In this study we investigated its in vitro cytotoxicity on human squamous cell carcinoma cells followed by metabolomic profiling of Carica papaya leaf decoction and leaf juice/brewed leaf juice to determine the effects imparted by the long heating process typical of the Aboriginal remedy preparation. MTT assay results showed that in comparison with the decoction, the leaf juice not only exhibited a stronger cytotoxic effect on SCC25 cancer cells, but also produced a significant cancer-selective effect as shown by tests on non-cancerous human keratinocyte HaCaT cells. Furthermore, evidence from testing brewed leaf juice on these two cell lines suggested that the brewing process markedly reduced the selective effect of Carica papaya leaf on SCC25 cancer cells. To tentatively identify the compounds that contribute to the distinct selective anticancer activity of leaf juice, an untargeted metabolomic approach employing Ultra High Performance Liquid Chromatography-Quadrupole Time of Flight-Mass Spectrometry followed by multivariate data analysis was applied. Some 90 and 104 peaks in positive and negative mode respectively were selected as discriminatory features from the chemical profile of leaf juice and >1500 putative compound IDs were obtained via database searching. Direct comparison of chromatographic and tandem mass spectral data to available reference compounds confirmed one feature as a match with its proposed authentic standard, namely pheophorbide A. However, despite pheophorbide A exhibiting cytotoxic activity on SCC25 cancer cells, it did not prove to be the compound contributing principally to the selective activity of leaf juice. With promising results suggesting stronger and more selective anticancer effects when compared to the Aboriginal remedy, Carica papaya leaf juice warrants further study to explore its activity on other cancer cell lines, as well as investigation to confirm the identity of compounds contributing to its selective effect, particularly those compounds altered by the long heating process applied during the traditional Aboriginal remedy preparation. PMID:26829042

Modifications in plasma membrane lipid composition and morphological features of AH-130 hepatoma cells by polyenylphosphatidylcholine in vivo treatment.

PubMed

Cinosi, Vincenzo; Antonini, Roberto; Crateri, Pasqualina; Arancia, Giuseppe

2011-07-01

The plasma membrane lipid composition in AH-130 hepatoma cells was found to change remarkably after polyenylphosphatidylcholine (PPC) treatment. Plasma membranes from cells grown in rats treated for 7 days i.v. with 20 mg/kg/day PPC, when compared to those of control cells, did not show significantly different amounts of cholesterol or phospholipids relative to protein content, but, surprisingly, the individual phospholipid distribution inside the two membrane leaflets changed dramatically. Phosphatidylcholine (PC), the major phospholipid in the external membrane leaflet, increased ~47% (p<0.001). By contrast, phosphatidylethanolamine (PE), the most important component of the inner leaflet, decreased nearly 37% (p<0.001), while sphingomyelin (SM) also decreased ~17%, (p=0.1). Tumor cells collected from control rats at the same time interval and observed by scanning electron microscopy, exhibited a spherical shape with numerous and randomly distributed long microvilli, the same morphological and ultrastructural features displayed by the implanted cells. Conversely, tumor cells from PPC-treated rats no longer showed the roundish cell profile, and microvilli appeared shortened and enlarged, with the formation of surface blebs. Transmission electron microscopy observations confirmed the morphological and ultrastructural cell changes, mainly seen as loss of microvilli and intense cytoplasmic vacuolization. Taken together, these results indicate that the new phospholipid class distribution in the plasma membrane leaflets, modifying tumor cell viable structures, produced heavy cell damage and in many cases brought about complete cellular disintegration.

Biomass enzymatic saccharification is determined by the non-KOH-extractable wall polymer features that predominately affect cellulose crystallinity in corn.

PubMed

Jia, Jun; Yu, Bin; Wu, Leiming; Wang, Hongwu; Wu, Zhiliang; Li, Ming; Huang, Pengyan; Feng, Shengqiu; Chen, Peng; Zheng, Yonglian; Peng, Liangcai

2014-01-01

Corn is a major food crop with enormous biomass residues for biofuel production. Due to cell wall recalcitrance, it becomes essential to identify the key factors of lignocellulose on biomass saccharification. In this study, we examined total 40 corn accessions that displayed a diverse cell wall composition. Correlation analysis showed that cellulose and lignin levels negatively affected biomass digestibility after NaOH pretreatments at p<0.05 & 0.01, but hemicelluloses did not show any significant impact on hexoses yields. Comparative analysis of five standard pairs of corn samples indicated that cellulose and lignin should not be the major factors on biomass saccharification after pretreatments with NaOH and H2SO4 at three concentrations. Notably, despite that the non-KOH-extractable residues covered 12%-23% hemicelluloses and lignin of total biomass, their wall polymer features exhibited the predominant effects on biomass enzymatic hydrolysis including Ara substitution degree of xylan (reverse Xyl/Ara) and S/G ratio of lignin. Furthermore, the non-KOH-extractable polymer features could significantly affect lignocellulose crystallinity at p<0.05, leading to a high biomass digestibility. Hence, this study could suggest an optimal approach for genetic modification of plant cell walls in bioenergy corn.

Biomass Enzymatic Saccharification Is Determined by the Non-KOH-Extractable Wall Polymer Features That Predominately Affect Cellulose Crystallinity in Corn

PubMed Central

Wu, Leiming; Wang, Hongwu; Wu, Zhiliang; Li, Ming; Huang, Pengyan; Feng, Shengqiu; Chen, Peng; Zheng, Yonglian; Peng, Liangcai

2014-01-01

Corn is a major food crop with enormous biomass residues for biofuel production. Due to cell wall recalcitrance, it becomes essential to identify the key factors of lignocellulose on biomass saccharification. In this study, we examined total 40 corn accessions that displayed a diverse cell wall composition. Correlation analysis showed that cellulose and lignin levels negatively affected biomass digestibility after NaOH pretreatments at p<0.05 & 0.01, but hemicelluloses did not show any significant impact on hexoses yields. Comparative analysis of five standard pairs of corn samples indicated that cellulose and lignin should not be the major factors on biomass saccharification after pretreatments with NaOH and H2SO4 at three concentrations. Notably, despite that the non-KOH-extractable residues covered 12%–23% hemicelluloses and lignin of total biomass, their wall polymer features exhibited the predominant effects on biomass enzymatic hydrolysis including Ara substitution degree of xylan (reverse Xyl/Ara) and S/G ratio of lignin. Furthermore, the non-KOH-extractable polymer features could significantly affect lignocellulose crystallinity at p<0.05, leading to a high biomass digestibility. Hence, this study could suggest an optimal approach for genetic modification of plant cell walls in bioenergy corn. PMID:25251456

Cell-free protein synthesis in micro compartments: building a minimal cell from biobricks.

PubMed

Jia, Haiyang; Heymann, Michael; Bernhard, Frank; Schwille, Petra; Kai, Lei

2017-10-25

The construction of a minimal cell that exhibits the essential characteristics of life is a great challenge in the field of synthetic biology. Assembling a minimal cell requires multidisciplinary expertise from physics, chemistry and biology. Scientists from different backgrounds tend to define the essence of 'life' differently and have thus proposed different artificial cell models possessing one or several essential features of living cells. Using the tools and methods of molecular biology, the bottom-up engineering of a minimal cell appears in reach. However, several challenges still remain. In particular, the integration of individual sub-systems that is required to achieve a self-reproducing cell model presents a complex optimization challenge. For example, multiple self-organisation and self-assembly processes have to be carefully tuned. We review advances and developments of new methods and techniques, for cell-free protein synthesis as well as micro-fabrication, for their potential to resolve challenges and to accelerate the development of minimal cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Derivation of Pluripotent Stem Cells with In Vivo Embryonic and Extraembryonic Potency.

PubMed

Yang, Yang; Liu, Bei; Xu, Jun; Wang, Jinlin; Wu, Jun; Shi, Cheng; Xu, Yaxing; Dong, Jiebin; Wang, Chengyan; Lai, Weifeng; Zhu, Jialiang; Xiong, Liang; Zhu, Dicong; Li, Xiang; Yang, Weifeng; Yamauchi, Takayoshi; Sugawara, Atsushi; Li, Zhongwei; Sun, Fangyuan; Li, Xiangyun; Li, Chen; He, Aibin; Du, Yaqin; Wang, Ting; Zhao, Chaoran; Li, Haibo; Chi, Xiaochun; Zhang, Hongquan; Liu, Yifang; Li, Cheng; Duo, Shuguang; Yin, Ming; Shen, Huan; Belmonte, Juan Carlos Izpisua; Deng, Hongkui

2017-04-06

Of all known cultured stem cell types, pluripotent stem cells (PSCs) sit atop the landscape of developmental potency and are characterized by their ability to generate all cell types of an adult organism. However, PSCs show limited contribution to the extraembryonic placental tissues in vivo. Here, we show that a chemical cocktail enables the derivation of stem cells with unique functional and molecular features from mice and humans, designated as extended pluripotent stem (EPS) cells, which are capable of chimerizing both embryonic and extraembryonic tissues. Notably, a single mouse EPS cell shows widespread chimeric contribution to both embryonic and extraembryonic lineages in vivo and permits generating single-EPS-cell-derived mice by tetraploid complementation. Furthermore, human EPS cells exhibit interspecies chimeric competency in mouse conceptuses. Our findings constitute a first step toward capturing pluripotent stem cells with extraembryonic developmental potentials in culture and open new avenues for basic and translational research. VIDEO ABSTRACT. Copyright © 2017 Elsevier Inc. All rights reserved.

Hematopoietic stem cells from NOD mice exhibit autonomous behavior and a competitive advantage in allogeneic recipients.

PubMed

Chilton, Paula M; Rezzoug, Francine; Ratajczak, Mariusz Z; Fugier-Vivier, Isabelle; Ratajczak, Janina; Kucia, Magda; Huang, Yiming; Tanner, Michael K; Ildstad, Suzanne T

2005-03-01

Type 1 diabetes is a systemic autoimmune disease that can be cured by transplantation of hematopoietic stem cells (HSCs) from disease-resistant donors. Nonobese diabetic (NOD) mice have a number of features that distinguish them as bone marrow transplant recipients that must be understood prior to the clinical application of chimerism to induce tolerance. In the present studies, we characterized NOD HSCs, comparing their engraftment characteristics to HSCs from disease-resistant strains. Strikingly, NOD HSCs are significantly enhanced in engraftment potential compared with HSCs from disease-resistant donors. Unlike HSCs from disease-resistant strains, they do not require graft-facilitating cells to engraft in allogeneic recipients. Additionally, they exhibit a competitive advantage when coadministered with increasing numbers of syngeneic HSCs, produce significantly more spleen colony-forming units (CFU-Ss) in vivo in allogeneic recipients, and more granulocyte macrophage-colony-forming units (CFU-GMs) in vitro compared with HSCs from disease-resistant controls. NOD HSCs also exhibit significantly enhanced chemotaxis to a stromal cell-derived factor 1 (SDF-1) gradient and adhere significantly better on primary stroma. This enhanced engraftment potential maps to the insulin-dependent diabetes locus 9 (Idd9) locus, and as such the tumor necrosis factor (TNF) receptor family as well as ski/sno genes may be involved in the mechanism underlying the autonomy of NOD HSCs. These findings may have important implications to understand the evolution of autoimmune disease and impact on potential strategies for cure.

P63 EXPRESSION LEVELS IN SIDE POPULATION AND LOW LIGHT SCATTERING OCULAR SURFACE EPITHELIAL CELLS

PubMed Central

Epstein, Seth P; Wolosin, J. Mario; Asbell, Penny A

2005-01-01

Purpose Because stem cells exhibit high self-renewal capacity, slow cycling, and high proliferative potential, and one of many markers postulated for epithelial stem cells, p63, is challenged by widespread expression within stem cell–free regions, we examined p63 expression in these stem cell–associated cohorts compared with their controls. Methods Rabbit limbocorneal cryosections, cytospun cell-sorted (by fluorescence-activated cell sorter) side population (SP) and low side scatter (LSSC) cells, and limbal epithelial cells over feeders were stained for p63 by indirect immunofluorescence. Clones were fixed and stained daily for 7 days. Image analysis measured p63 intensity, plotting it against colony size. Results All basal limbal cells were positive for p63, yet only 5% to 7% expressed high p63 intensities, 40% intermediate, and the majority low. Side population cells were less than 1% of total cells. The average intensity of SP staining was three times that of controls. Subpopulations displaying stemlike features exhibited highest p63 expression. Replication rates of isolated cells differed. Day 5 colonies contained 256 (16 hours/cycle) to two (96 hours/cycle) cells. Whereas all cells were positive for p63, intensity in slow-cycling cells was three to four times that in rapidly proliferating congeners. Increased cell doublings did not decrease fluorescence. Conclusions Results suggest that p63 concentration is maximal in stem cells and decreases with differentiation. High p63 levels seem to correlate with cells of the SP and LSSC phenotypes, indicating high cell stemness. With identification of stem cells, further studies can elucidate their use in supporting ocular surface health. PMID:17057802

Differential chemokine, chemokine receptor and cytokine expression in Epstein-Barr virus-associated lymphoproliferative diseases.

PubMed

Ohshima, Koichi; Karube, Kennosuke; Hamasaki, Makoto; Tutiya, Takeshi; Yamaguchi, Takahiro; Suefuji, Hiroaki; Suzuki, Keiko; Suzumiya, Junji; Ohga, Shouichi; Kikuchi, Masahiro

2003-08-01

T cell immunity plays an important role in the clinicopathology of Epstein-Barr virus (EBV)-associated diseases. Acute EBV-induced infectious mononucleosis (IM) is a common self-limiting disease, however, other EBV-associated diseases, including chronic active EBV infection (CAEBV), NK cell lymphoma (NKL), and Hodgkin's lymphoma (HL), exhibit distinct clinical features. Chemokines are members of a family of small-secreted proteins. The relationships between chemokines and the chemokine receptor (R) are thought to be important for selectivity of local immunity. Some chemokines, chemokine R and cytokines closely associate with the T cell subtypes, Th1 and Th2 T cells and cytotoxic cells. To clarify the role of T cell immunity in EBV-associated diseases, we conducted gene expression profiling, using chemokine, chemokine R and cytokine DNA chips. Compared to EBV negative non-specific lymphadenitis, CAEBV and NKL exhibited diffuse down- and up-regulation, respectively, of these gene profiles. IM had a predominantly Th1-type profile, whereas HL had a mixed Th1/Th2-type profile. Reduction of the Th1-type cytokine interferon gamma (IFN-gamma) in CAEBV was confirmed by Reverse transcriptase-polymerase chain reaction, whereas IFN-gamma expression was markedly enhanced in NKL, and moderately enhanced in IM. Compared to IM, CAEBV showed slight elevation of "regulated upon activation, normal T expressed and secreted" (RANTES), but almost all other genes assayed were down-regulated. NKL exhibited elevated expression of numerous genes, particularly IFN-gamma-inducible-10 (IP-10) and monokine induced by IFN-gamma (MIG). HL showed variable elevated and reduced expression of various genes, with increased expression of IL-13 receptor and MIG. Our study demonstrated the enormous potential of gene expression profiling for clarifying the pathogenesis of EBV-associated diseases.

Osteopontin-a splice variant is overexpressed in papillary thyroid carcinoma and modulates invasive behavior

PubMed Central

Ferreira, Luciana Bueno; Tavares, Catarina; Pestana, Ana; Pereira, Catarina Leite; Eloy, Catarina; Pinto, Marta Teixeira; Castro, Patricia; Batista, Rui; Rios, Elisabete; Sobrinho-Simões, Manuel; Pereira Gimba, Etel Rodrigues; Soares, Paula

2016-01-01

Osteopontin (OPN) is a matricellular protein overexpressed in cancer cells and modulates tumorigenesis and metastasis, including in thyroid cancer (TC). The contribution of each OPN splice variant (OPN-SV), named OPNa, OPNb and OPNc, in TC is currently unknown. This study evaluates the expression of total OPN (tOPN) and OPN-SV in TC tissues and cell lines, their correlation with clinicopathological, molecular features and their functional roles. We showed that tOPN and OPNa are overexpressed in classic papillary thyroid carcinoma (cPTC) in relation to adjacent thyroid, adenoma and follicular variant of papillary thyroid carcinoma (fvPTC) tissues. In cPTC, OPNa overexpression is associated with larger tumor size, vascular invasion, extrathyroid extension and BRAFV600E mutation. We found that TC cell lines overexpressing OPNa exhibited increased proliferation, migration, motility and in vivo invasion. Conditioned medium secreted from cells overexpressing OPNa induce MMP2 and MMP9 metalloproteinases activity. In summary, we described the expression pattern of OPN-SV in cPTC samples and the key role of OPNa expression on activating TC tumor progression features. Our findings highlight OPNa variant as TC biomarker, besides being a putative target for cPTC therapeutic approaches. PMID:27409830

Osteopontin-a splice variant is overexpressed in papillary thyroid carcinoma and modulates invasive behavior.

PubMed

Ferreira, Luciana Bueno; Tavares, Catarina; Pestana, Ana; Pereira, Catarina Leite; Eloy, Catarina; Pinto, Marta Teixeira; Castro, Patricia; Batista, Rui; Rios, Elisabete; Sobrinho-Simões, Manuel; Gimba, Etel Rodrigues Pereira; Soares, Paula

2016-08-09

Osteopontin (OPN) is a matricellular protein overexpressed in cancer cells and modulates tumorigenesis and metastasis, including in thyroid cancer (TC). The contribution of each OPN splice variant (OPN-SV), named OPNa, OPNb and OPNc, in TC is currently unknown. This study evaluates the expression of total OPN (tOPN) and OPN-SV in TC tissues and cell lines, their correlation with clinicopathological, molecular features and their functional roles. We showed that tOPN and OPNa are overexpressed in classic papillary thyroid carcinoma (cPTC) in relation to adjacent thyroid, adenoma and follicular variant of papillary thyroid carcinoma (fvPTC) tissues. In cPTC, OPNa overexpression is associated with larger tumor size, vascular invasion, extrathyroid extension and BRAFV600E mutation. We found that TC cell lines overexpressing OPNa exhibited increased proliferation, migration, motility and in vivo invasion. Conditioned medium secreted from cells overexpressing OPNa induce MMP2 and MMP9 metalloproteinases activity. In summary, we described the expression pattern of OPN-SV in cPTC samples and the key role of OPNa expression on activating TC tumor progression features. Our findings highlight OPNa variant as TC biomarker, besides being a putative target for cPTC therapeutic approaches.

Influence of Surface Energy on Organic Alloy Formation in Ternary Blend Solar Cells Based on Two Donor Polymers.

PubMed

Gobalasingham, Nemal S; Noh, Sangtaik; Howard, Jenna B; Thompson, Barry C

2016-10-05

The compositional dependence of the open-circuit voltage (V oc ) in ternary blend bulk heterojunction (BHJ) solar cells is correlated with the miscibility of polymers, which may be influenced by a number of attributes, including crystallinity, the random copolymer effect, or surface energy. Four ternary blend systems featuring poly(3-hexylthiophene-co-3-(2-ethylhexyl)thiophene) (P3HT 75 -co-EHT 25 ), poly(3-hexylthiophene-co-(hexyl-3-carboxylate)), herein referred to as poly(3-hexylthiophene-co-3-hexylesterthiophene) (P3HT 50 -co-3HET 50 ), poly(3-hexylthiophene-thiophene-diketopyrrolopyrrole) (P3HTT-DPP-10%), and an analog of P3HTT-DPP-10% with 40% of 3-hexylthiophene exchanged for 2-(2-methoxyethoxy)ethylthiophen-2-yl (3MEO-T) (featuring an electronically decoupled oligoether side-chain), referred to as P3HTTDPP-MEO40%, are explored in this work. All four polymers are semicrystalline and rich in rr-P3HT content and perform well in binary devices with PC 61 BM. Except for P3HTTDPP-MEO40%, all polymers exhibit similar surface energies (∼21-22 mN/m). P3HTTDPP-MEO40% exhibits an elevated surface energy of around 26 mN/m. As a result, despite the similar optoelectronic properties and binary solar cell performance of P3HTTDPP-MEO40% compared to P3HTT-DPP-10%, the former exhibits a pinned V oc in two different sets of ternary blend devices. This is a stark contrast to previous rr-P3HT-based systems and demonstrates that surface energy, and its influence on miscibility, plays a critical role in the formation of organic alloys and can supersede the influence of crystallinity, the random copolymer effect, similar backbone structures, and HOMO/LUMO considerations. Therefore, we confirm surface energy compatibility as a figure-of-merit for predicting the compositional dependence of the V oc in ternary blend solar cells and highlight the importance of polymer miscibility in organic alloy formation.

Transfection of the Human Heme Oxygenase Gene Into Rabbit Coronary Microvessel Endothelial Cells: Protective Effect Against Heme and Hemoglobin Toxicity

NASA Astrophysics Data System (ADS)

Abraham, N. G.; Lavrovsky, Y.; Schwartzman, M. L.; Stoltz, R. A.; Levere, R. D.; Gerritsen, M. E.

1995-07-01

Heme oxygenase (HO) is a stress protein and has been suggested to participate in defense mechanisms against agents that may induce oxidative injury such as metals, endotoxin, heme/hemoglobin, and various cytokines. Overexpression of HO in cells might therefore protect against oxidative stress produced by certain of these agents, specifically heme and hemoglobin, by catalyzing their degradation to bilirubin, which itself has antioxidant properties. We report here the successful in vitro transfection of rabbit coronary microvessel endothelial cells with a functioning gene encoding the human HO enzyme. A plasmid containing the cytomegalovirus promoter and the human HO cDNA complexed to cationic liposomes (Lipofectin) was used to transfect rabbit endothelial cells. Cells transfected with human HO exhibited an ≈3.0-fold increase in enzyme activity and expressed a severalfold induction of human HO mRNA as compared with endogenous rabbit HO mRNA. Transfected and nontransfected cells expressed factor VIII antigen and exhibited similar acetylated low-density lipoprotein uptake (two important features that characterize endothelial cells) with >85% of cells staining positive for each marker. Moreover, cells transfected with the human HO gene acquired substantial resistance to toxicity produced by exposure to recombinant hemoglobin and heme as compared with nontransfected cells. The protective effect of HO overexpression against heme/hemoglobin toxicity in endothelial cells shown in these studies provides direct evidence that the inductive response of human HO to such injurious stimuli represents an important tissue adaptive mechanism for moderating the severity of cell damage produced by these blood components.

Roles of ON Cone Bipolar Cell Subtypes in Temporal Coding in the Mouse Retina

PubMed Central

Fyk-Kolodziej, Bozena; Cohn, Jesse

2014-01-01

In the visual system, diverse image processing starts with bipolar cells, which are the second-order neurons of the retina. Thirteen subtypes of bipolar cells have been identified, which are thought to encode different features of image signaling and to initiate distinct signal-processing streams. Although morphologically identified, the functional roles of each bipolar cell subtype in visual signal encoding are not fully understood. Here, we investigated how ON cone bipolar cells of the mouse retina encode diverse temporal image signaling. We recorded bipolar cell voltage changes in response to two different input functions: sinusoidal light and step light stimuli. Temporal tuning in ON cone bipolar cells was diverse and occurred in a subtype-dependent manner. Subtypes 5s and 8 exhibited low-pass filtering property in response to a sinusoidal light stimulus, and responded with sustained fashion to step-light stimulation. Conversely, subtypes 5f, 6, 7, and XBC exhibited bandpass filtering property in response to sinusoidal light stimuli, and responded transiently to step-light stimuli. In particular, subtypes 7 and XBC were high-temporal tuning cells. We recorded responses in different ways to further examine the underlying mechanisms of temporal tuning. Current injection evoked low-pass filtering, whereas light responses in voltage-clamp mode produced bandpass filtering in all ON bipolar cells. These findings suggest that cone photoreceptor inputs shape bandpass filtering in bipolar cells, whereas intrinsic properties of bipolar cells shape low-pass filtering. Together, our results demonstrate that ON bipolar cells encode diverse temporal image signaling in a subtype-dependent manner to initiate temporal visual information-processing pathways. PMID:24966376

Bacterial chemoreceptors: high-performance signaling in networked arrays.

PubMed

Hazelbauer, Gerald L; Falke, Joseph J; Parkinson, John S

2008-01-01

Chemoreceptors are crucial components in the bacterial sensory systems that mediate chemotaxis. Chemotactic responses exhibit exquisite sensitivity, extensive dynamic range and precise adaptation. The mechanisms that mediate these high-performance functions involve not only actions of individual proteins but also interactions among clusters of components, localized in extensive patches of thousands of molecules. Recently, these patches have been imaged in native cells, important features of chemoreceptor structure and on-off switching have been identified, and new insights have been gained into the structural basis and functional consequences of higher order interactions among sensory components. These new data suggest multiple levels of molecular interactions, each of which contribute specific functional features and together create a sophisticated signaling device.

Bacterial chemoreceptors: high-performance signaling in networked arrays

PubMed Central

Hazelbauer, Gerald L.; Falke, Joseph J.; Parkinson, John S.

2010-01-01

Chemoreceptors are crucial components in the bacterial sensory systems that mediate chemotaxis. Chemotactic responses exhibit exquisite sensitivity, extensive dynamic range and precise adaptation. The mechanisms that mediate these high-performance functions involve not only actions of individual proteins but also interactions among clusters of components, localized in extensive patches of thousands of molecules. Recently, these patches have been imaged in native cells, important features of chemoreceptor structure and on–off switching have been identified, and new insights have been gained into the structural basis and functional consequences of higher order interactions among sensory components. These new data suggest multiple levels of molecular interactions, each of which contribute specific functional features and together create a sophisticated signaling device. PMID:18165013

JAK2V617F-mutant megakaryocytes contribute to hematopoietic stem/progenitor cell expansion in a model of murine myeloproliferation

PubMed Central

Zhan, H; Ma, Y; Lin, CHS; Kaushansky, K

2016-01-01

The myeloproliferative neoplasms (MPNs) are characterized by hematopoietic stem/progenitor cell (HSPC) expansion and overproduction of mature blood cells. The JAK2V617F mutation is present in hematopoietic cells in a majority of patients with MPNs, but the mechanism(s) responsible for MPN stem cell expansion remain incomplete. One hallmark feature of the marrow in patients with MPNs is megakaryocyte (MK) hyperplasia. We report here that mice bearing a human JAK2V617F gene restricted exclusively to the MK lineage develop many of the features of a MPN. Specifically, these mice exhibit thrombocytosis, splenomegaly, increased numbers of marrow and splenic hematopoietic progenitors and a substantial expansion of HSPCs. In addition, wild-type mice transplanted with cells from JAK2V617F-bearing MK marrow develop a myeloproliferative syndrome with thrombocytosis and erythrocytosis as well as pan-hematopoietic progenitor and stem cell expansion. As marrow histology in this murine model of myeloproliferation reveals a preferentially perivascular localization of JAK2V617F-mutant MKs and an increased marrow sinusoid vascular density, it adds to accumulating data that MKs are an important component of the marrow HSPC niche, and that MK expansion might indirectly contribute to the critical role of the thrombopoietin/c-Mpl signaling pathway in HSPC maintenance and expansion. PMID:27133820

Ultrastrukturelle Untersuchungen zur Morphologie und Genese der Spermien von Archaeogastropoda

NASA Astrophysics Data System (ADS)

Kohnert, R.; Storch, V.

1983-03-01

The sperm cells of Patella coerulea (Patellacea), Monodonta turbinata, and Gibbula tumida (Trochacea) were investigated by means of transmission electron microscopy. They belong to the primitive type (sensu Franzén) and have more features in common with primitive Bivalvia sperms than with Neritacea. Their head contains an apical acrosome and a roundish nucleus followed by 4 or 5 mitochondria and a centriolar apparatus which consists of two centrioles, one of which bears a flagellum. The sperm cells of Monodonta and Gibbula are very similar to each other and differ mainly in size; Patella exhibits more differences (very small acrosome, subacrosomal space, variable number of spherical mitochondria (origin of spermic dimorphism ?). The development of the sperm cells shows no peculiarities.

Dynamics and interactions of particles in a thermophoretic trap

NASA Astrophysics Data System (ADS)

Foster, Benjamin; Fung, Frankie; Fieweger, Connor; Usatyuk, Mykhaylo; Gaj, Anita; DeSalvo, B. J.; Chin, Cheng

2017-08-01

We investigate dynamics and interactions of particles levitated and trapped by the thermophoretic force in a vacuum cell. Our analysis is based on footage taken by orthogonal cameras that are able to capture the three dimensional trajectories of the particles. In contrast to spherical particles, which remain stationary at the center of the cell, here we report new qualitative features of the motion of particles with non-spherical geometry. Singly levitated particles exhibit steady spinning around their body axis and rotation around the symmetry axis of the cell. When two levitated particles approach each other, repulsive or attractive interactions between the particles are observed. Our levitation system offers a wonderful platform to study interaction between particles in a microgravity environment.

Stem Cell Therapy: Repurposing Cell-Based Regenerative Medicine Beyond Cell Replacement.

PubMed

Napoli, Eleonora; Lippert, Trenton; Borlongan, Cesar V

2018-02-27

Stem cells exhibit simple and naive cellular features, yet their exact purpose for regenerative medicine continues to elude even the most elegantly designed research paradigms from developmental biology to clinical therapeutics. Based on their capacity to divide indefinitely and their dynamic differentiation into any type of tissue, the advent of transplantable stem cells has offered a potential treatment for aging-related and injury-mediated diseases. Recent laboratory evidence has demonstrated that transplanted human neural stem cells facilitate endogenous reparative mechanisms by initiating multiple regenerative processes in the brain neurogenic areas. Within these highly proliferative niches reside a myriad of potent regenerative molecules, including anti-inflammatory cytokines, proteomes, and neurotrophic factors, altogether representing a biochemical cocktail vital for restoring brain function in the aging and diseased brain. Here, we advance the concept of therapeutically repurposing stem cells not towards cell replacement per se, but rather exploiting the cells' intrinsic properties to serve as the host brain regenerative catalysts.

Cancer stem cells, cancer cell plasticity and radiation therapy.

PubMed

Vlashi, Erina; Pajonk, Frank

2015-04-01

Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cellular Interactions and Immune Response of Spherical Nucleic Acid (SNA) Nanoconjugates

NASA Astrophysics Data System (ADS)

Massich, Matthew David

Spherical nucleic acid (SNA) nanoconjugates consist of a densely packed monolayer shell of highly-oriented oligonucleotides covalently bound to a gold nanoparticle core. The nanoconjugates exhibit several important qualities, which make them useful for various biological applications, such as antisense gene regulation strategies and the intracellular detection of biomolecules. The focus of this thesis was to characterize the nanoconjugates interaction with cultured cells and specifically the immune response to their intracellular presence. The immune response of macrophage cells to internalized nanoconjugates was studied, and due to the dense functionalization of oligonucleotides on the surface of the nanoparticle and the resulting high localized salt concentration the innate immune response to the nanoconjugates is ˜25-fold less when compared to a lipoplex carrying the same sequence. Additionally, genome-wide expression profiling was used to study the biological response of cultured cells to the nanoconjugates. The biological response of HeLa cells to gold nanoparticles stabilized by weakly bound ligands was significant, yet when these same nanoparticles were stably functionalized with covalently attached oligonucleotides the cells showed no measurable response. In human keratinocytes, the oligonucleotide sequences caused 427 genes to be differentially expressed when complexed with Dharmafect, but when the oligonucleotides were conjugated to nanoparticles only 7 genes were differentially expressed. Beyond characterizing the cellular interactions and immune response of the nanoconjugates, the optimal length of siRNA (from 19--34 base pairs) that induces the most gene knockdown while maintaining limited immune activation was determined to be 24 base pairs. Further, the SNAs were shown to be useful as a potential antiviral gene therapy by demonstrating approximately 50% knockdown of the Ebola VP35 gene. Lastly, a scanning probe-enabled method was used to rapidly create nanoscale fibronectin patterns over large areas with a range of feature sizes, thereby opening the field of nanocombinatorics. This allowed the investigation of the relationship between fibronectin feature size and stem cell fate. MSCs cultured on nanoscale fibronectin features directed differentiation toward osteogenesis to a greater extent than cells grown on both microscale features and cells grown on non-patterned fibronectin substrates with osteogenic inducing media, demonstrating a new method for controlling stem cell fate.

Acantholytic squamous cell carcinoma is usually associated with hair follicles, not acantholytic actinic keratosis, and is not “high risk”: Diagnosis, management, and clinical outcomes in a series of 115 cases

PubMed Central

Ogawa, Toru; Kiuru, Maija; Konia, Thomas H.; Fung, Maxwell A.

2017-01-01

Background Acantholytic squamous cell carcinoma (aSCC) is regarded as a high-risk variant of cutaneous squamous cell carcinoma (SCC). Acantholytic actinic keratosis (aAK) has been regarded as a precursor risk factor for aSCC. However, supporting evidence is limited. Objective We sought to document clinical features, histologic features, management, and outcomes in a series of aSCC cases. Methods Definitions of aSCC, aAK, and aSCC arising in association with aAK were applied to a consecutive series of aSCC cases. Clinical characteristics and outcomes were obtained from electronic medical records. Results Of 115 aSCC cases (103 patients, mean age 71.8 years), actinic keratosis was present in 23% (27/115) but only 7.8% (9/115) exhibited associated aAK. Ten cases (10/115, 9%) fulfilled strict histologic criteria for follicular SCC as previously defined, but 50 of 115 (43%) of our aSCC cases exhibited predominant involvement of follicular epithelium rather than epidermis. Clinical outcome (median follow-up, 36 months) was available in 106 of 115 (92%). One patient experienced regional extension (parotid), and 1 patient experienced a local recurrence (nose). No disease-related metastases or deaths were documented. Limitations This was a single-institution retrospective study from the United States. Conclusions The presence of acantholysis in cutaneous SCC does not specifically confer aggressive behavior, a finding that may inform clinical practice guidelines. PMID:27889291

Acantholytic squamous cell carcinoma is usually associated with hair follicles, not acantholytic actinic keratosis, and is not "high risk": Diagnosis, management, and clinical outcomes in a series of 115 cases.

PubMed

Ogawa, Toru; Kiuru, Maija; Konia, Thomas H; Fung, Maxwell A

2017-02-01

Acantholytic squamous cell carcinoma (aSCC) is regarded as a high-risk variant of cutaneous squamous cell carcinoma (SCC). Acantholytic actinic keratosis (aAK) has been regarded as a precursor risk factor for aSCC. However, supporting evidence is limited. We sought to document clinical features, histologic features, management, and outcomes in a series of aSCC cases. Definitions of aSCC, aAK, and aSCC arising in association with aAK were applied to a consecutive series of aSCC cases. Clinical characteristics and outcomes were obtained from electronic medical records. Of 115 aSCC cases (103 patients, mean age 71.8 years), actinic keratosis was present in 23% (27/115) but only 7.8% (9/115) exhibited associated aAK. Ten cases (10/115, 9%) fulfilled strict histologic criteria for follicular SCC as previously defined, but 50 of 115 (43%) of our aSCC cases exhibited predominant involvement of follicular epithelium rather than epidermis. Clinical outcome (median follow-up, 36 months) was available in 106 of 115 (92%). One patient experienced regional extension (parotid), and 1 patient experienced a local recurrence (nose). No disease-related metastases or deaths were documented. This was a single-institution retrospective study from the United States. The presence of acantholysis in cutaneous SCC does not specifically confer aggressive behavior, a finding that may inform clinical practice guidelines. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Mode of action and synergistic effect of valinomycin and cereulide with amphotericin B against Candida albicans and Cryptococcus albidus.

PubMed

Makarasen, A; Reukngam, N; Khlaychan, P; Chuysinuan, P; Isobe, M; Techasakul, S

2018-03-01

Both valinomycin and cereulide are cyclic depsipeptides and are known K + ion-selective ionophores. Valinomycin and cereulide feature low minimum inhibitory concentration (MIC) values against Candida albicans and Cryptococcus albidus. This study aims at investigating the mode of action and verifying the efficacy of valinomycin or cereulide alone and in combination with amphotericin B (AmB) in vitro against both microorganisms. Based on the results from membrane permeability and fluidity assays for detection of plasma membrane permeabilization and membrane dynamics, the present study demonstrated that valinomycin and cereulide exhibit antifungal activity against C. albicans and C. albidus by interrupting membrane-associated function. The mode of action of both valinomycin and cereulide are similar with that of AmB. Time-kill kinetics assay showed that valinomycin and cereulide exhibit fungistatic activity, whereas AmB features fungicidal activity. Additionally, the combination of compounds between each cyclic peptide and AmB reached maximal fungicidal activity more rapidly than AmB alone. This result corresponded with findings of scanning electron microscopy, fractional inhibitory concentration index and minimum fungicidal concentration (MFC)/MIC ratio, indicating that combinations of the drugs show synergistic effects for inhibiting the growth of these fungal strains. Sorbitol and ergosterol assays showed that both cyclic peptides affected cell wall and membrane components due to increases in MIC value, as observed in medium with sorbitol and ergosterol. Valinomycin and cereulide may promote permeability of fungal cell wall and cell membrane when used in combination with AmB. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Primary diffuse large B cell lymphoma arising from a leiomyoma of the uterine corpus.

PubMed

Zhao, Lianhua; Ma, Qiang; Wang, Qiushi; Zeng, Ying; Luo, Qingya; Xiao, Hualiang

2016-01-20

Primary diffuse large B cell lymphoma (DLBCL) of the uterus is rare, and primary DLBCL arising from a uterine leiomyoma (collision tumor) has not been reported in the literature. We describe the clinical, histological, immunohistochemical, and molecular features of primary DLBCL arising from a leiomyoma in the uterine corpus. A 73-year-old female patient had a uterine mass for 23 years. An ultrasound scan revealed marked enlargement of the uterus, measuring 18.2 × 13 × 16.3 cm, with a 17.6 × 10.9 × 11.6 cm hypoechoic mass in the uterine corpus. The tumors consisted of medium- to large-sized cells exhibiting a diffuse pattern of growth with a well-circumscribed leiomyoma. The neoplastic cells strongly expressed CD79α, CD20 and PAX5. Molecular analyses indicated clonal B-cell receptor gene rearrangement. To the best of our knowledge, no previous cases of primary DLBCL arising from a leiomyoma have been reported. It is necessary to differentiate a diagnosis of primary DLBCL arising from a leiomyoma from that of leiomyoma with florid reactive lymphocytic infiltration (lymphoma-like lesion). Careful analysis of clinical, histological, immunophenotypic, and genetic features is required to establish the correct diagnosis.

Premature aging induced by radiation exhibits pro-atherosclerotic effects mediated by epigenetic activation of CD44 expression

PubMed Central

Lowe, Donna; Raj, Kenneth

2014-01-01

Age is undoubtedly a major risk factor for heart disease. However, the reason for this is not entirely clear. In the course of our investigation into the mechanism of radiation-induced cardiovascular disease, we made several unexpected findings that inform us on this question. We observed that human coronary endothelial cells, while being able to initiate repair of radiation-induced DNA damage, often fail to complete the repair and become senescent. Such radiation-induced cellular aging occurs through a mutation-independent route. Endothelial cells that aged naturally through replication or as a result of radiation exhibited indistinguishable characteristics. The promoter regions of the CD44 gene in aging endothelial cells become demethylated, and the proteins are highly expressed on the cell surface, making the cells adhesive for monocytes. Adhesion is a cardinal feature that recruits monocytes to the endothelium, allowing them to infiltrate the vessel wall and initiate atherosclerosis. The epigenetic activation of CD44 expression is particularly significant as it causes persistent elevated CD44 protein expression, making senescent endothelial cells chronically adhesive. In addition to understanding why cardiovascular disease increases with age, these observations provide insights into the puzzling association between radiation and cardiovascular disease and highlight the need to consider premature aging as an additional risk of radiation to human health. PMID:25059316

TGFβ1-induced down-regulation of microRNA-138 contributes to epithelial-mesenchymal transition in primary lung cancer cells.

PubMed

Zhang, Fang; Li, Tiepeng; Han, Lu; Qin, Peng; Wu, Zhao; Xu, Benling; Gao, Quanli; Song, Yongping

2018-02-19

The existence of cancer stem cells within the tumor could lead to cancer therapy resistance. TGFβ1 is considered as one of the most powerful players in the generation of CSCs through induction of epithelial-mesenchymal transition in different types of cancer including lung cancer, however, the detailed mechanisms by which TGFβ1 contribute to EMT induction and CSC maintenance remains unclear. Here, we showed primary lung cancer cells treated by TGFβ1 exhibit mesenchymal features, including morphology and expression of mesenchymal marker in a time-dependent manner. We also observed long-term TGFβ1 exposure leads to an enrichment of a sub-population of CD44 + CD90 + cells which represent CSCs in lung cancer cells. Moreover, the differential expression microRNAs between CSCs and non-CSCs were identified using next-generation sequencing to screen key miRNAs which might contribute to TGFβ1-induced EMT and CSCs generation. Among those differentially expressed miRNAs, the expression of microRNA-138 was time-dependently down-regulated by TGFβ1 treatment. We further demonstrated primary lung cancer cells, in which we knockdown the expression of miR-138, exhibit mesenchymal phenotypes and stem cell properties. Taken together, these findings indicate TGFβ1-induced down-regulation of microRNA-138 contributes to EMT in primary lung cancer cells, and suggest that miR-138 might serve as a potential therapeutic target. Copyright © 2018 Elsevier Inc. All rights reserved.

New physical concepts for cell amoeboid motion.

PubMed Central

Evans, E

1993-01-01

Amoeboid motion of cells is an essential mechanism in the function of many biological organisms (e.g., the regiment of scavenger cells in the immune defense system of animals). This process involves rapid chemical polymerization (with numerous protein constituents) to create a musclelike contractile network that advances the cell over the surface. Significant progress has been made in the biology and biochemistry of motile cells, but the physical dynamics of cell spreading and contraction are not well understood. The reason is that general approaches are formulated from complex mass, momentum, and chemical reaction equations for multiphase-multicomponent flow with the nontrivial difficulty of moving boundaries. However, there are strong clues to the dynamics that allow bold steps to be taken in simplifying the physics of motion. First, amoeboid cells often exhibit exceptional kinematics, i.e., steady advance and retraction of local fixed-shape patterns. Second, recent evidence has shown that cell projections "grow" by polymerization along the advancing boundary of the cell. Together, these characteristics represent a local growth process pinned to the interfacial contour of a contractile network. As such, the moving boundary becomes tractable, but subtle features of the motion lead to specific requirements for the chemical nature of the boundary polymerization process. To demonstrate these features, simple examples for limiting conditions of substrate interaction (i.e., "strong" and "weak" adhesion) are compared with data from experimental studies of yeast particle engulfment by blood granulocytes and actin network dynamics in fishscale keratocytes. Images FIGURE 2 FIGURE 4 PMID:8494986

New physical concepts for cell amoeboid motion.

PubMed

Evans, E

1993-04-01

Amoeboid motion of cells is an essential mechanism in the function of many biological organisms (e.g., the regiment of scavenger cells in the immune defense system of animals). This process involves rapid chemical polymerization (with numerous protein constituents) to create a musclelike contractile network that advances the cell over the surface. Significant progress has been made in the biology and biochemistry of motile cells, but the physical dynamics of cell spreading and contraction are not well understood. The reason is that general approaches are formulated from complex mass, momentum, and chemical reaction equations for multiphase-multicomponent flow with the nontrivial difficulty of moving boundaries. However, there are strong clues to the dynamics that allow bold steps to be taken in simplifying the physics of motion. First, amoeboid cells often exhibit exceptional kinematics, i.e., steady advance and retraction of local fixed-shape patterns. Second, recent evidence has shown that cell projections "grow" by polymerization along the advancing boundary of the cell. Together, these characteristics represent a local growth process pinned to the interfacial contour of a contractile network. As such, the moving boundary becomes tractable, but subtle features of the motion lead to specific requirements for the chemical nature of the boundary polymerization process. To demonstrate these features, simple examples for limiting conditions of substrate interaction (i.e., "strong" and "weak" adhesion) are compared with data from experimental studies of yeast particle engulfment by blood granulocytes and actin network dynamics in fishscale keratocytes.

Wong-Type Dermatomyositis Showing Porokeratosis-Like Changes (Columnar Dyskeratosis): A Case Report and Review of the Literature

PubMed Central

Umanoff, Nicole; Fisher, Ari; Carlson, J. Andrew

2015-01-01

Background Wong-type dermatomyositis (DM) exhibits simultaneous pityriasis rubra pilaris (PRP) features. Case Report A 50-year-old woman presented with a heliotrope rash, Gottron's papules, and a poikilodermic, erythematous rash in shawl distribution without evidence of muscle weakness. Despite topical corticosteroids, the eruption progressed 9 months later to include generalized hyperkeratotic follicular papules, islands of sparing, and atrophic macules with a collarette of scale suggestive of porokeratosis. Mild dysphonia was the only sign of muscle weakness. Serology showed positive ANA. Histopathology revealed interface dermatitis with dermal mucin and melanophages, irregular psoriasiform hyperplasia, alternating mounds of para- and orthokeratosis, and tiers of dyskeratotic cells (columnar dyskeratosis). Systemic corticosteroid therapy was not tolerated; acitretin diminished the hyperkeratosis. While hyperpigmentation persisted, no progression of cutaneous or muscular symptoms has occurred after 22 months of follow-up and cessation of the therapy. Overall, her course did not differ from the natural history documented in the literature review of Wong-type DM. The most similar case also exhibited pseudocornoid lamella changes. Conclusion Wong-type DM is a clinicopathologic DM-PRP hybrid that can also exhibit porokeratosis-like features best described as columnar dyskeratosis. Recognizing these types of lesions in DM is warranted in order to make an accurate assessment of their prognostic significance. PMID:27047930

Polyoma small T antigen triggers cell death via mitotic catastrophe

PubMed Central

Fernando, Arun T Pores; Andrabi, Shaida; Cizmecioglu, Onur; Zhu, Cailei; Livingston, David M.; Higgins, Jonathan M.G; Schaffhausen, Brian S; Roberts, Thomas M

2014-01-01

Polyoma small T antigen (PyST), an early gene product of the polyoma virus, has been shown to cause cell death in a number of mammalian cells in a protein phosphatase 2A (PP2A)-dependent manner. In the current study, using a cell line featuring regulated expression of PyST, we found that PyST arrests cells in mitosis. Live-cell and immunofluorescence studies showed that the majority of the PyST-expressing cells were arrested in prometaphase with almost no cells progressing beyond metaphase. These cells exhibited defects in chromosomal congression, sister chromatid cohesion and spindle positioning, resulting in the activation of the Spindle Assembly Checkpoint (SAC). Prolonged mitotic arrest then led to cell death via mitotic catastrophe. Cell cycle inhibitors that block cells in G1/S prevented PyST-induced death. PyST-induced cell death that occurs during M is not dependent on p53 status. These data suggested, and our results confirmed that, PP2A inhibition could be used to preferentially kill cancer cells with p53 mutations that proliferate normally in the presence of cell cycle inhibitors. PMID:24998850

From fibroblasts and stem cells: implications for cell therapies and somatic cloning.

PubMed

Kues, Wilfried A; Carnwath, Joseph W; Niemann, Heiner

2005-01-01

Pluripotent embryonic stem cells (ESCs) from the inner cell mass of early murine and human embryos exhibit extensive self-renewal in culture and maintain their ability to differentiate into all cell lineages. These features make ESCs a suitable candidate for cell-replacement therapy. However, the use of early embryos has provoked considerable public debate based on ethical considerations. From this standpoint, stem cells derived from adult tissues are a more easily accepted alternative. Recent results suggest that adult stem cells have a broader range of potency than imagined initially. Although some claims have been called into question by the discovery that fusion between the stem cells and differentiated cells can occur spontaneously, in other cases somatic stem cells have been induced to commit to various lineages by the extra- or intracellular environment. Recent data from our laboratory suggest that changes in culture conditions can expand a subpopulation of cells with a pluripotent phenotype from primary fibroblast cultures. The present paper critically reviews recent data on the potency of somatic stem cells, methods to modify the potency of somatic cells and implications for cell-based therapies.

Synthesis of Chrysogeside B from Halotolerant Fungus Penicillium and Its Antimicrobial Activities Evaluation

NASA Astrophysics Data System (ADS)

Liu, Ruiquan; Wang, Lei; Li, Qibo; Liao, Min; Yang, Zhikun; Huang, Yun; Lv, Cong; Zheng, Bing; Zhong, Jiangchun; Bian, Qinghua; Wang, Min; Liu, Shangzhong

2017-04-01

Chrysogeside B, a natural cerebroside, was efficiently synthesized from commercial feedstocks. The bioassays showed that compounds 4, 5 and 6 exhibited enhanced biological activities compared Chrysogeside B. Further studies revealed that free hydroxyl groups and glycosidic bond have significant impact on the antimicrobial activities. The synthesis of Chrysogeside B and analogues designed to allow identification of the features of this glycolipid required for recognition by tested bacteria and Hela cells is described.

Frequency locking in auditory hair cells: Distinguishing between additive and parametric forcing

NASA Astrophysics Data System (ADS)

Edri, Yuval; Bozovic, Dolores; Yochelis, Arik

2016-10-01

The auditory system displays remarkable sensitivity and frequency discrimination, attributes shown to rely on an amplification process that involves a mechanical as well as a biochemical response. Models that display proximity to an oscillatory onset (also known as Hopf bifurcation) exhibit a resonant response to distinct frequencies of incoming sound, and can explain many features of the amplification phenomenology. To understand the dynamics of this resonance, frequency locking is examined in a system near the Hopf bifurcation and subject to two types of driving forces: additive and parametric. Derivation of a universal amplitude equation that contains both forcing terms enables a study of their relative impact on the hair cell response. In the parametric case, although the resonant solutions are 1 : 1 frequency locked, they show the coexistence of solutions obeying a phase shift of π, a feature typical of the 2 : 1 resonance. Different characteristics are predicted for the transition from unlocked to locked solutions, leading to smooth or abrupt dynamics in response to different types of forcing. The theoretical framework provides a more realistic model of the auditory system, which incorporates a direct modulation of the internal control parameter by an applied drive. The results presented here can be generalized to many other media, including Faraday waves, chemical reactions, and elastically driven cardiomyocytes, which are known to exhibit resonant behavior.

Overexpression of molecular chaperons GRP78 and GRP94 in CD44(hi)/CD24(lo) breast cancer stem cells.

PubMed

Nami, Babak; Ghasemi-Dizgah, Armin; Vaseghi, Akbar

2016-01-01

Breast cancer stem cell with CD44(hi)/CD24(lo) phonotype is described having stem cell properties and represented as the main driving factor in breast cancer initiation, growth, metastasis and low response to anti-cancer agents. Glucoseregulated proteins (GRPs) are heat shock protein family chaperons that are charged with regulation of protein machinery and modulation of endoplasmic reticulum homeostasis whose important roles in stem cell development and invasion of various cancers have been demonstrated. Here, we investigated the expression levels of GRP78 and GRP94 in CD44(hi)/CD24(lo) phenotype breast cancer stem cells (BCSCs). MCF7, T-47D and MDA-MB-231 breast cancer cell lines were used. CD44(hi)/CD24(lo) phenotype cell population were analyzed and sorted by fluorescence-activated cell sorting (FACS). Transcriptional and translational expression of GRP78 and GRP94 were investigated by western blotting and quantitative real time PCR. RESULTS showed different proportion of CD44(hi)/CD24(lo) phenotype cell population in their original bulk cells. The ranking of the cell lines in terms of CD44(hi)/CD24(lo) phenotype cell population was as MCF7

Molecular analysis of neutrophil differentiation from human iPSCs delineates the kinetics of key regulators of hematopoiesis

PubMed Central

Sweeney, Colin L.; Teng, Ruifeng; Wang, Hongmei; Merling, Randall K.; Lee, Janet; Choi, Uimook; Koontz, Sherry; Wright, Daniel G.; Malech, Harry L.

2016-01-01

In vitro generation of mature neutrophils from human induced pluripotent stem cells (iPSCs) requires hematopoietic progenitor development followed by myeloid differentiation. The purpose of our studies was to extensively characterize this process, focusing on the critical window of development between hemogenic endothelium, hematopoietic stem/progenitor cells (HSPCs), and myeloid commitment, to identify associated regulators and markers that might enable the stem cell field to improve the efficiency and efficacy of iPSC hematopoiesis. We utilized a 4-stage differentiation protocol involving: embryoid body (EB) formation (Stage-1); EB culture with hematopoietic cytokines (Stage-2); HSPC expansion (Stage-3); and neutrophil maturation (Stage-4). CD34+CD45− putative hemogenic endothelial cells were observed in Stage-3 cultures, and expressed VEGFR-2/Flk-1/KDR and VE-cadherin endothelial markers, GATA-2, AML1/RUNX1, and SCL/TAL1 transcription factors, and endothelial/HSPC-associated microRNAs miR-24, miR-125a-3p, miR-126/126*, and miR-155. Upon further culture, CD34+CD45− cells generated CD34+CD45+ HSPCs that produced hematopoietic CFUs. Mid-Stage-3 CD34+CD45+ HSPCs exhibited increased expression of GATA-2, AML1/RUNX1, SCL/TAL1, C/EBPα, and PU.1 transcription factors, but exhibited decreased expression of HSPC-associated microRNAs, and failed to engraft in immune-deficient mice. Mid-stage-3 CD34−CD45+ cells maintained PU.1 expression and exhibited increased expression of hematopoiesis-associated miR-142-3p/5p and a trend towards increased miR-223 expression, indicating myeloid commitment. By late Stage-4, increased CD15, CD16b, and C/EBPε expression were observed, with 25–65% of cells exhibiting morphology and functions of mature neutrophils. These studies demonstrate that hematopoiesis and neutrophil differentiation from human iPSCs recapitulates many features of embryonic hematopoiesis and neutrophil production in marrow, but reveals unexpected molecular signatures that may serve as a guide for enhancing iPSC hematopoiesis. PMID:26866427

Identification of aberrant gene expression associated with aberrant promoter methylation in primordial germ cells between E13 and E16 rat F3 generation vinclozolin lineage.

PubMed

Taguchi, Y-h

2015-01-01

Transgenerational epigenetics (TGE) are currently considered important in disease, but the mechanisms involved are not yet fully understood. TGE abnormalities expected to cause disease are likely to be initiated during development and to be mediated by aberrant gene expression associated with aberrant promoter methylation that is heritable between generations. However, because methylation is removed and then re-established during development, it is not easy to identify promoter methylation abnormalities by comparing normal lineages with those expected to exhibit TGE abnormalities. This study applied the recently proposed principal component analysis (PCA)-based unsupervised feature extraction to previously reported and publically available gene expression/promoter methylation profiles of rat primordial germ cells, between E13 and E16 of the F3 generation vinclozolin lineage that are expected to exhibit TGE abnormalities, to identify multiple genes that exhibited aberrant gene expression/promoter methylation during development. The biological feasibility of the identified genes were tested via enrichment analyses of various biological concepts including pathway analysis, gene ontology terms and protein-protein interactions. All validations suggested superiority of the proposed method over three conventional and popular supervised methods that employed t test, limma and significance analysis of microarrays, respectively. The identified genes were globally related to tumors, the prostate, kidney, testis and the immune system and were previously reported to be related to various diseases caused by TGE. Among the genes reported by PCA-based unsupervised feature extraction, we propose that chemokine signaling pathways and leucine rich repeat proteins are key factors that initiate transgenerational epigenetic-mediated diseases, because multiple genes included in these two categories were identified in this study.

Identification of aberrant gene expression associated with aberrant promoter methylation in primordial germ cells between E13 and E16 rat F3 generation vinclozolin lineage

PubMed Central

2015-01-01

Background Transgenerational epigenetics (TGE) are currently considered important in disease, but the mechanisms involved are not yet fully understood. TGE abnormalities expected to cause disease are likely to be initiated during development and to be mediated by aberrant gene expression associated with aberrant promoter methylation that is heritable between generations. However, because methylation is removed and then re-established during development, it is not easy to identify promoter methylation abnormalities by comparing normal lineages with those expected to exhibit TGE abnormalities. Methods This study applied the recently proposed principal component analysis (PCA)-based unsupervised feature extraction to previously reported and publically available gene expression/promoter methylation profiles of rat primordial germ cells, between E13 and E16 of the F3 generation vinclozolin lineage that are expected to exhibit TGE abnormalities, to identify multiple genes that exhibited aberrant gene expression/promoter methylation during development. Results The biological feasibility of the identified genes were tested via enrichment analyses of various biological concepts including pathway analysis, gene ontology terms and protein-protein interactions. All validations suggested superiority of the proposed method over three conventional and popular supervised methods that employed t test, limma and significance analysis of microarrays, respectively. The identified genes were globally related to tumors, the prostate, kidney, testis and the immune system and were previously reported to be related to various diseases caused by TGE. Conclusions Among the genes reported by PCA-based unsupervised feature extraction, we propose that chemokine signaling pathways and leucine rich repeat proteins are key factors that initiate transgenerational epigenetic-mediated diseases, because multiple genes included in these two categories were identified in this study. PMID:26677731

Chemotherapy-Induced Depletion of OCT4-Positive Cancer Stem Cells in a Mouse Model of Malignant Testicular Cancer.

PubMed

Pierpont, Timothy M; Lyndaker, Amy M; Anderson, Claire M; Jin, Qiming; Moore, Elizabeth S; Roden, Jamie L; Braxton, Alicia; Bagepalli, Lina; Kataria, Nandita; Hu, Hilary Zhaoxu; Garness, Jason; Cook, Matthew S; Capel, Blanche; Schlafer, Donald H; Southard, Teresa; Weiss, Robert S

2017-11-14

Testicular germ cell tumors (TGCTs) are among the most responsive solid cancers to conventional chemotherapy. To elucidate the underlying mechanisms, we developed a mouse TGCT model featuring germ cell-specific Kras activation and Pten inactivation. The resulting mice developed malignant, metastatic TGCTs composed of teratoma and embryonal carcinoma, the latter of which exhibited stem cell characteristics, including expression of the pluripotency factor OCT4. Consistent with epidemiological data linking human testicular cancer risk to in utero exposures, embryonic germ cells were susceptible to malignant transformation, whereas adult germ cells underwent apoptosis in response to the same oncogenic events. Treatment of tumor-bearing mice with genotoxic chemotherapy not only prolonged survival and reduced tumor size but also selectively eliminated the OCT4-positive cancer stem cells. We conclude that the chemosensitivity of TGCTs derives from the sensitivity of their cancer stem cells to DNA-damaging chemotherapy. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Multicellular contractility contributes to the emergence of mesothelioma nodules

NASA Astrophysics Data System (ADS)

Czirok, Andras

Malignant pleural mesothelioma (MPM) nodules arise from the mesothelial lining of the pleural cavity by a poorly understood mechanism. We demonstrate that macroscopic multicellular aggregates, reminiscent of the MPM nodules found in patients, develop when MPM cell lines are cultured at high cell densities for several weeks. Surprisingly, the nodule-like aggregates do not arise by excessive local cell proliferation, but by myosin II-driven cell contractility. Contractile nodules contain prominent actin cables that can span several cells. Several features of the in vitro MPM nodule development can be explained by a computational model that assumes uniform and steady intercellular contractile forces within a monolayer of cells, and a mechanical load-dependent lifetime of cell-cell contacts. The model behaves as a self-tensioned Maxwell fluid and exhibits an instability that leads to pattern formation. Altogether, our findings suggest that inhibition of the actomyosin system may provide a hitherto not utilized therapeutic approach to affect MPM growth. NIH R01-GM102801.

Stem cell and neurogenic gene-expression profiles link prostate basal cells to aggressive prostate cancer

PubMed Central

Zhang, Dingxiao; Park, Daechan; Zhong, Yi; Lu, Yue; Rycaj, Kiera; Gong, Shuai; Chen, Xin; Liu, Xin; Chao, Hsueh-Ping; Whitney, Pamela; Calhoun-Davis, Tammy; Takata, Yoko; Shen, Jianjun; Iyer, Vishwanath R.; Tang, Dean G.

2016-01-01

The prostate gland mainly contains basal and luminal cells constructed as a pseudostratified epithelium. Annotation of prostate epithelial transcriptomes provides a foundation for discoveries that can impact disease understanding and treatment. Here we describe a genome-wide transcriptome analysis of human benign prostatic basal and luminal epithelial populations using deep RNA sequencing. Through molecular and biological characterizations, we show that the differential gene-expression profiles account for their distinct functional properties. Strikingly, basal cells preferentially express gene categories associated with stem cells, neurogenesis and ribosomal RNA (rRNA) biogenesis. Consistent with this profile, basal cells functionally exhibit intrinsic stem-like and neurogenic properties with enhanced rRNA transcription activity. Of clinical relevance, the basal cell gene-expression profile is enriched in advanced, anaplastic, castration-resistant and metastatic prostate cancers. Therefore, we link the cell-type-specific gene signatures to aggressive subtypes of prostate cancer and identify gene signatures associated with adverse clinical features. PMID:26924072

Stem cell and neurogenic gene-expression profiles link prostate basal cells to aggressive prostate cancer.

PubMed

Zhang, Dingxiao; Park, Daechan; Zhong, Yi; Lu, Yue; Rycaj, Kiera; Gong, Shuai; Chen, Xin; Liu, Xin; Chao, Hsueh-Ping; Whitney, Pamela; Calhoun-Davis, Tammy; Takata, Yoko; Shen, Jianjun; Iyer, Vishwanath R; Tang, Dean G

2016-02-29

The prostate gland mainly contains basal and luminal cells constructed as a pseudostratified epithelium. Annotation of prostate epithelial transcriptomes provides a foundation for discoveries that can impact disease understanding and treatment. Here we describe a genome-wide transcriptome analysis of human benign prostatic basal and luminal epithelial populations using deep RNA sequencing. Through molecular and biological characterizations, we show that the differential gene-expression profiles account for their distinct functional properties. Strikingly, basal cells preferentially express gene categories associated with stem cells, neurogenesis and ribosomal RNA (rRNA) biogenesis. Consistent with this profile, basal cells functionally exhibit intrinsic stem-like and neurogenic properties with enhanced rRNA transcription activity. Of clinical relevance, the basal cell gene-expression profile is enriched in advanced, anaplastic, castration-resistant and metastatic prostate cancers. Therefore, we link the cell-type-specific gene signatures to aggressive subtypes of prostate cancer and identify gene signatures associated with adverse clinical features.

Satellite cell senescence underlies myopathy in a mouse model of limb-girdle muscular dystrophy 2H

PubMed Central

Kudryashova, Elena; Kramerova, Irina; Spencer, Melissa J.

2012-01-01

Mutations in the E3 ubiquitin ligase tripartite motif-containing 32 (TRIM32) are responsible for the disease limb-girdle muscular dystrophy 2H (LGMD2H). Previously, we generated Trim32 knockout mice (Trim32–/– mice) and showed that they display a myopathic phenotype accompanied by neurogenic features. Here, we used these mice to investigate the muscle-specific defects arising from the absence of TRIM32, which underlie the myopathic phenotype. Using 2 models of induced atrophy, we showed that TRIM32 is dispensable for muscle atrophy. Conversely, TRIM32 was necessary for muscle regrowth after atrophy. Furthermore, TRIM32-deficient primary myoblasts underwent premature senescence and impaired myogenesis due to accumulation of PIAS4, an E3 SUMO ligase and TRIM32 substrate that was previously shown to be associated with senescence. Premature senescence of myoblasts was also observed in vivo in an atrophy/regrowth model. Trim32–/– muscles had substantially fewer activated satellite cells, increased PIAS4 levels, and growth failure compared with wild-type muscles. Moreover, Trim32–/– muscles exhibited features of premature sarcopenia, such as selective type II fast fiber atrophy. These results imply that premature senescence of muscle satellite cells is an underlying pathogenic feature of LGMD2H and reveal what we believe to be a new mechanism of muscular dystrophy associated with reductions in available satellite cells and premature sarcopenia. PMID:22505452

New tools for the analysis of glial cell biology in Drosophila.

PubMed

Awasaki, Takeshi; Lee, Tzumin

2011-09-01

Because of its genetic, molecular, and behavioral tractability, Drosophila has emerged as a powerful model system for studying molecular and cellular mechanisms underlying the development and function of nervous systems. The Drosophila nervous system has fewer neurons and exhibits a lower glia:neuron ratio than is seen in vertebrate nervous systems. Despite the simplicity of the Drosophila nervous system, glial organization in flies is as sophisticated as it is in vertebrates. Furthermore, fly glial cells play vital roles in neural development and behavior. In addition, powerful genetic tools are continuously being created to explore cell function in vivo. In taking advantage of these features, the fly nervous system serves as an excellent model system to study general aspects of glial cell development and function in vivo. In this article, we review and discuss advanced genetic tools that are potentially useful for understanding glial cell biology in Drosophila. Copyright © 2011 Wiley-Liss, Inc.

Projection-specific visual feature encoding by layer 5 cortical subnetworks

PubMed Central

Lur, Gyorgy; Vinck, Martin A.; Tang, Lan; Cardin, Jessica A.; Higley, Michael J.

2016-01-01

Summary Primary neocortical sensory areas act as central hubs, distributing afferent information to numerous cortical and subcortical structures. However, it remains unclear whether each downstream target receives distinct versions of sensory information. We used in vivo calcium imaging combined with retrograde tracing to monitor visual response properties of three distinct subpopulations of projection neurons in primary visual cortex. While there is overlap across the groups, on average corticotectal (CT) cells exhibit lower contrast thresholds and broader tuning for orientation and spatial frequency in comparison to corticostriatal (CS) cells, while corticocortical (CC) cells have intermediate properties. Noise correlational analyses support the hypothesis that CT cells integrate information across diverse layer 5 populations, whereas CS and CC cells form more selectively interconnected groups. Overall, our findings demonstrate the existence of functional subnetworks within layer 5 that may differentially route visual information to behaviorally relevant downstream targets. PMID:26972011

Eliminating Cancer Stem Cells by Targeting Embryonic Signaling Pathways.

PubMed

Oren, Ohad; Smith, B Douglas

2017-02-01

Dramatic advances have been made in the understanding of cancer over the past decade. Prime among those are better appreciation of the biology of cancer and the development of targeted therapies. Despite these improvements, however, most tumors remain refractory to anti-cancer medications and frequently recur. Cancer Stem Cells (CSCs), which in some cases express markers of pluripotency (e.g., Oct-4), share many of the molecular features of normal stem cells. These cells have been hypothesised to play a role in tumor resistance and relapse. They exhibit dependence on many primitive regulatory pathways and may be best viewed in the context of embryonic signaling pathways. In this article, we review important embryonic signaling cascades and their differential expression in CSCs. We also discuss these pathways as actionable targets for novel therapies in hopes that eliminating cancer stem cells will lead to an improvement in overall survival for patients.

Activator-inhibitor coupling between Rho signaling and actin assembly make the cell cortex an excitable medium

PubMed Central

Bement, William M.; Leda, Marcin; Moe, Alison M.; Kita, Angela M.; Larson, Matthew E.; Golding, Adriana E.; Pfeuti, Courtney; Su, Kuan-Chung; Miller, Ann L.; Goryachev, Andrew B.; von Dassow, George

2016-01-01

Animal cell cytokinesis results from patterned activation of the small GTPase Rho, which directs assembly of actomyosin in the equatorial cortex. Cytokinesis is restricted to a portion of the cell cycle following anaphase onset in which the cortex is responsive to signals from the spindle. We show that shortly after anaphase onset oocytes and embryonic cells of frogs and echinoderms exhibit cortical waves of Rho activity and F-actin polymerization. The waves are modulated by cyclin-dependent kinase 1 (Cdk1) activity and require the Rho GEF (guanine nucleotide exchange factor), Ect2. Surprisingly, during wave propagation, while Rho activity elicits F-actin assembly, F-actin subsequently inactivates Rho. Experimental and modeling results show that waves represent excitable dynamics of a reaction diffusion system with Rho as the activator and F-actin the inhibitor. We propose that cortical excitability explains fundamental features of cytokinesis including its cell cycle regulation. PMID:26479320

A short protocol using dexamethasone and monophosphoryl lipid A generates tolerogenic dendritic cells that display a potent migratory capacity to lymphoid chemokines

PubMed Central

2013-01-01

Background Generation of tolerogenic dendritic cells (TolDCs) for therapy is challenging due to its implications for the design of protocols suitable for clinical applications, which means not only using safe products, but also working at defining specific biomarkers for TolDCs identification, developing shorter DCs differentiation methods and obtaining TolDCs with a stable phenotype. We describe here, a short-term protocol for TolDCs generation, which are characterized in terms of phenotypic markers, cytokines secretion profile, CD4+ T cell-stimulatory ability and migratory capacity. Methods TolDCs from healthy donors were generated by modulation with dexamethasone plus monophosphoryl lipid A (MPLA-tDCs). We performed an analysis of MPLA-tDCs in terms of yield, viability, morphology, phenotypic markers, cytokines secretion profile, stability, allogeneic and antigen-specific CD4+ T-cell stimulatory ability and migration capacity. Results After a 5-day culture, MPLA-tDCs displayed reduced expression of costimulatory and maturation molecules together to an anti-inflammatory cytokines secretion profile, being able to maintain these tolerogenic features even after the engagement of CD40 by its cognate ligand. In addition, MPLA-tDCs exhibited reduced capabilities to stimulate allogeneic and antigen-specific CD4+ T cell proliferation, and induced an anti-inflammatory cytokine secretion pattern. Among potential tolerogenic markers studied, only TLR-2 was highly expressed in MPLA-tDCs when compared to mature and immature DCs. Remarkable, like mature DCs, MPLA-tDCs displayed a high CCR7 and CXCR4 expression, both chemokine receptors involved in migration to secondary lymphoid organs, and even more, in an in vitro assay they exhibited a high migration response towards CCL19 and CXCL12. Conclusion We describe a short-term protocol for TolDC generation, which confers them a stable phenotype and migratory capacity to lymphoid chemokines, essential features for TolDCs to be used as therapeutics for autoimmunity and prevention of graft rejection. PMID:23706017

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.

Thermally stable, low resistance contact systems for use with shallow junction p(+) nn(+) and n(+)pp(+) InP solar cells

NASA Technical Reports Server (NTRS)

Weizer, V. G.; Fatemi, N. S.; Hoffman, R. W.

1995-01-01

Two contact systems for use on shallow junction InP solar cells are described. The feature shared by these two contact systems is the absence of the metallurgical intermixing that normally takes place between the semiconductor and the contact metallization during the sintering process. The n(+)pp(+) cell contact system, consisting of a combination of Au and Ge, not only exhibits very low resistance in the as-fabricated state, but also yields post-sinter resistivity values of 1(exp -7) ohms-sq cm, with effectively no metal-InP interdiffusion. The n(+)pp(+)cell contact system, consisting of a combination of Ag and Zn, permits low resistance ohmic contact to be made directly to a shallow junction p/n InP device without harming the device itself during the contacting process.

A unique cell-surface protein phenotype distinguishes human small-cell from non-small-cell lung cancer

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

Baylin, S.B.; Gazdar, A.F.; Minna, J.D.

1982-08-01

Radioiodination (/sup 125/I) and two-dimensional polyacrylamide gel electrophoresis was used to determine that small-(oat) cell lung carcinoma (SCC)-a tumor with neuroedocrine features-possesses a surface protein pattern distinct from the other types of lung cancer cells (squamous, adeno-, and large-cell undifferentiated carcinoma). Twelve distinguishing proteins, 40 to 70 kilodaltons (kDal), characterized four separate lines of SCC; three of these, designated E (60 kDal; pI = 7.3), S (30 kDal; pI = 6.0), and U 57 kDal; pI = 5.6), may be unique SCC gene products and were identified only in (/sup 35/S)methionine labeling of SCC and not in non-SCC or humanmore » fibroblasts. Two lines of adeno-, one of squamous, and one of undifferentiated large-cell lung carcinoma exhibited similar surface protein patterns to one another. Nine distinguishing proteins (40 to 100 kDal) and at least five large proteins (>100 kDal) were unique to these lines. The surface protein phenotypes for SCC and non-SCC were distinct from those for human lymphoblastoid cells and fibroblasts. However, the neuroendocrine features of SCC were further substantiated because 6 of the 12 distinguishing SCC surface proteins, including E and U, were identified on human neuroblastoma cells. The proteins identified should (i) help define differentiation steps for normal and neoplastic bronchial epithelial cells, (ii) prove useful in better classifying lung cancers, and (iii) be instrumental in tracing formation of neuroendocrine cells.« less

Tissue-nonspecific Alkaline Phosphatase Deficiency Causes Abnormal Craniofacial Bone Development in the Alpl−/− Mouse Model of Infantile Hypophosphatasia

PubMed Central

Liu, Jin; Nam, Hwa Kyung; Campbell, Cassie; Gasque, Kellen Cristina da Silva; Millán, José Luis; Hatch, Nan E.

2014-01-01

Tissue-nonspecific alkaline phosphatase (TNAP) is an enzyme present on the surface of mineralizing cells and their derived matrix vesicles that promotes hydroxyapatite crystal growth. Hypophosphatasia (HPP) is an inborn-error-of-metabolism that, dependent upon age of onset, features rickets or osteomalacia due to loss-of function mutations in the gene (Alpl) encoding TNAP. Craniosynostosis is prevalent in infants with HPP and other forms of rachitic disease but how craniosynostosis develops in these disorders is unknown. Objectives: Because craniosynostosis carries high morbidity, we are investigating craniofacial skeletal abnormalities in Alpl−/− mice to establish these mice as a model of HPP-associated craniosynostosis and determine mechanisms by which TNAP influences craniofacial skeletal development. Methods: Cranial bone, cranial suture and cranial base abnormalities were analyzed by micro-CT and histology. Craniofacial shape abnormalities were quantified using digital calipers. TNAP expression was suppressed in MC3T3E1(C4) calvarial cells by TNAP-specific shRNA. Cells were analyzed for changes in mineralization, gene expression, proliferation, apoptosis, matrix deposition and cell adhesion. Results: Alpl−/− mice feature craniofacial shape abnormalities suggestive of limited anterior-posterior growth. Craniosynostosis in the form of bony coronal suture fusion is present by three weeks after birth. Alpl−/− mice also exhibit marked histologic abnormalities of calvarial bones and the cranial base involving growth plates, cortical and trabecular bone within two weeks of birth. Analysis of calvarial cells in which TNAP expression was suppressed by shRNA indicates that TNAP deficiency promotes aberrant osteoblastic gene expression, diminished matrix deposition, diminished proliferation, increased apoptosis and increased cell adhesion. Conclusions: These findings demonstrate that Alpl−/− mice exhibit a craniofacial skeletal phenotype similar to that seen in infants with HPP, including true bony craniosynostosis in the context of severely diminished bone mineralization. Future studies will be required to determine if TNAP deficiency and other forms of rickets promote craniosynostosis directly through abnormal calvarial cell behavior, or indirectly due to deficient growth of the cranial base. PMID:25014884

Internalization of aggregated photosensitizers by tumor cells: subcellular time-resolved fluorescence spectroscopy on derivatives of pyropheophorbide-a ethers and chlorin e6 under femtosecond one- and two-photon excitations.

PubMed

Kelbauskas, L; Dietel, W

2002-12-01

Amphiphilic sensitizers self-associate in aqueous environments and form aggregated species that exhibit no or only negligible photodynamic activity. However, amphiphilic photosensitizers number among the most potent agents of photodynamic therapy. The processes by which these sensitizers are internalized into tumor cells have yet to be fully elucidated and thus remain the subject of debate. In this study the uptake of photosensitizer aggregates into tumor cells was examined directly using subcellular time-resolved fluorescence spectroscopy with a high temporal resolution (20-30 ps) and high sensitivity (time-correlated single-photon counting). The investigations were performed on selected sensitizers that exhibit short fluorescence decay times (< 50 ps) in aggregated form. Derivatives of pyropheophorbide-a ether and chlorin e6 with varying lipophilicity were used for the study. The characteristic fluorescence decay times and spectroscopic features of the sensitizer aggregates measured in aqueous solution also could be observed in A431 human endothelial carcinoma cells administered with these photosensitizers. This shows that tumor cells can internalize sensitizers in aggregated form. Uptake of aggregates and their monomerization inside cells were demonstrated directly for the first time by means of fluorescence lifetime imaging with a high temporal resolution. Internalization of the aggregates seems to be endocytosis mediated. The degree of their monomerization in tumor cells is strongly influenced by the lipophilicity of the compounds.

Altered Hepa1-6 cells by dimethyl sulfoxide (DMSO)-treatment induce anti-tumor immunity in vivo.

PubMed

Jiang, Zhengyu; Zhang, Hongxia; Wang, Ye; Yu, Bin; Wang, Chen; Liu, Changcheng; Lu, Juan; Chen, Fei; Wang, Minjun; Yu, Xinlu; Lin, Jiahao; Pan, Xinghua; Wang, Pin; Zhu, Haiying

2016-02-23

Cancer immunotherapy is the use of the immune system to treat cancer. Our current research proposed an optional strategy of activating immune system involving in cancer immunotherapy. When being treated with 2% DMSO in culture medium, Hepa1-6 cells showed depressed proliferation with no significant apoptosis or decreased viability. D-hep cells, Hepa1-6 cells treated with DMSO for 7 days, could restore to the higher proliferation rate in DMSO-free medium, but alteration of gene expression profile was irreversible. Interestingly, tumors from D-hep cells, not Hepa1-6 cells, regressed in wild-type C57BL/6 mice whereas D-hep cells exhibited similar tumorigenesis as Hep1-6 cells in immunodeficient mice. As expected, additional Hepa1-6 cells failed to form tumors in the D-hep-C57 mice in which D-hep cells were eliminated. Further research confirmed that D-hep-C57 mice established anti-tumor immunity against Hepa1-6 cells. Our research proposed viable tumor cells with altered biological features by DMSO-treatment could induce anti-tumor immunity in vivo.

IL‐12 and IL‐15 induce the expression of CXCR6 and CD49a on peripheral natural killer cells

PubMed Central

Hydes, Theresa; Noll, Angela; Salinas‐Riester, Gabriela; Abuhilal, Mohammed; Armstrong, Thomas; Hamady, Zaed; Primrose, John; Takhar, Arjun; Walter, Lutz

2017-01-01

Abstract Introduction Murine hepatic NK cells exhibit adaptive features, with liver‐specific adhesion molecules CXCR6 and CD49a acting as surface markers. Methods We investigated human liver‐resident CXCR6+ and CD49a+ NK cells using RNA sequencing, flow cytometry, and functional analysis. We further assessed the role of cytokines in generating NK cells with these phenotypes from the peripheral blood. Results Hepatic CD49a+ NK cells could be induced using cytokines and produce high quantities of IFNγ and TNFα, in contrast to hepatic CXCR6+ NK cells. RNA sequencing of liver‐resident CXCR6+ NK cells confirmed a tolerant immature phenotype with reduced expression of markers associated with maturity and cytotoxicity. Liver‐resident double‐positive CXCR6 + CD49a+ hepatic NK cells are immature but maintain high expression of Th1 cytokines as observed for single‐positive CD49a+ NK cells. We show that stimulation with activating cytokines can readily induce upregulation of both CD49a and CXCR6 on NK cells in the peripheral blood. In particular, IL‐12 and IL‐15 can generate CXCR6 + CD49a+ NK cells in vitro from NK cells isolated from the peripheral blood, with comparable phenotypic and functional features to liver‐resident CD49a+ NK cells, including enhanced IFNγ and NKG2C expression. Conclusion IL‐12 and IL‐15 may be key for generating NK cells with a tissue‐homing phenotype and strong Th1 cytokine profile in the blood, and links peripheral activation of NK cells with tissue‐homing. These findings may have important therapeutic implications for immunotherapy of chronic liver disease. PMID:28952190

IL-12 and IL-15 induce the expression of CXCR6 and CD49a on peripheral natural killer cells.

PubMed

Hydes, Theresa; Noll, Angela; Salinas-Riester, Gabriela; Abuhilal, Mohammed; Armstrong, Thomas; Hamady, Zaed; Primrose, John; Takhar, Arjun; Walter, Lutz; Khakoo, Salim I

2018-03-01

Murine hepatic NK cells exhibit adaptive features, with liver-specific adhesion molecules CXCR6 and CD49a acting as surface markers. We investigated human liver-resident CXCR6+ and CD49a+ NK cells using RNA sequencing, flow cytometry, and functional analysis. We further assessed the role of cytokines in generating NK cells with these phenotypes from the peripheral blood. Hepatic CD49a+ NK cells could be induced using cytokines and produce high quantities of IFNγ and TNFα, in contrast to hepatic CXCR6+ NK cells. RNA sequencing of liver-resident CXCR6+ NK cells confirmed a tolerant immature phenotype with reduced expression of markers associated with maturity and cytotoxicity. Liver-resident double-positive CXCR6 + CD49a+ hepatic NK cells are immature but maintain high expression of Th1 cytokines as observed for single-positive CD49a+ NK cells. We show that stimulation with activating cytokines can readily induce upregulation of both CD49a and CXCR6 on NK cells in the peripheral blood. In particular, IL-12 and IL-15 can generate CXCR6 + CD49a+ NK cells in vitro from NK cells isolated from the peripheral blood, with comparable phenotypic and functional features to liver-resident CD49a+ NK cells, including enhanced IFNγ and NKG2C expression. IL-12 and IL-15 may be key for generating NK cells with a tissue-homing phenotype and strong Th1 cytokine profile in the blood, and links peripheral activation of NK cells with tissue-homing. These findings may have important therapeutic implications for immunotherapy of chronic liver disease. © 2017 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

Development and characterization of a human three-dimensional chondrosarcoma culture for in vitro drug testing.

PubMed

Voissiere, Aurélien; Jouberton, Elodie; Maubert, Elise; Degoul, Françoise; Peyrode, Caroline; Chezal, Jean-Michel; Miot-Noirault, Élisabeth

2017-01-01

It has been suggested that chemoresistance of chondrosarcoma (CHS), the cartilage tumor, is caused by the phenotypic microenvironmental features of the tumor tissue, mainly the chondrogenic extracellular matrix (ECM), and hypoxia. We developed and characterized a multicellular tumor spheroid (MCTS) of human chondrosarcoma HEMC-SS cells to gain insight into tumor cell biology and drug response. At Day 7, HEMC-SS spheroids exhibited a homogeneous distribution of proliferative Ki-67 positive cells, whereas in larger spheroids (Day 14 and Day 20), proliferation was mainly localized in the periphery. In the core of larger spheroids, apoptotic cells were evidenced by TUNEL assay, and hypoxia by pimonidazole staining. Interestingly, VEGF excretion, evidenced by ELISA on culture media, was detectable from Day 14 spheroids, and increased as the spheroids grew in size. HEMC-SS spheroids synthesized a chondrogenic extracellular matrix rich in glycosaminoglycans and type-2 collagen. Finally, we investigated the sensitivity of Day 7 and Day 14 chondrosarcoma MCTS to hypoxia-activated prodrug TH-302 and doxorubicin compared with their 2D counterparts. As expected, TH-302 exhibited higher cytotoxic activity on larger hypoxic spheroids (Day 14) than on non-hypoxic spheroids (Day 7), with multicellular resistance index (MCRI) values of 7.7 and 9.1 respectively. For doxorubicin, the larger-sized spheroids exhibited higher drug resistance (MCRI of 5.0 for Day 7 and 18.3 for Day 14 spheroids), possibly due to impeded drug penetration into the deep layer of spheroids, evidenced by its auto-fluorescence property. We have developed a model of human chondrosarcoma MCTS that combines an ECM rich in glycosaminoglycans with a high hypoxic core associated with VEGF excretion. This model could offer a more predictive in vitro chondrosarcoma system for screening drugs targeting tumor cells and their microenvironment.

Observed Properties of Giant Cells

NASA Technical Reports Server (NTRS)

Hathaway, David H.; Upton, Lisa; Colegrove, Owen

2014-01-01

The existence of Giant Cells has been suggested by both theory and observation for over 45 years. We have tracked the motions of supergranules in SDO/HMI Doppler velocity data and find larger (Giant Cell) flows that persist for months. The flows in these cells are clockwise around centers of divergence in the north and counter-clockwise in the south. Equatorward flows are correlated with prograde flows - giving the transport of angular momentum toward the equator that is needed to maintain the Sun's rapid equatorial rotation. The cells are most pronounced at mid- and high-latitudes where they exhibit the rotation rates representative of those latitudes. These are clearly large, long-lived, cellular features, with the dynamical characteristics expected from the effects of the Sun's rotation, but the shapes of the cells are not well represented in numerical models. While the Giant Cell flow velocities are small (<10 m/s), their long lifetimes should nonetheless substantially impact the transport of magnetic flux in the Sun's near surface layers.

A nanoporous alumina microelectrode array for functional cell-chip coupling.

PubMed

Wesche, Manuel; Hüske, Martin; Yakushenko, Alexey; Brüggemann, Dorothea; Mayer, Dirk; Offenhäusser, Andreas; Wolfrum, Bernhard

2012-12-14

The design of electrode interfaces has a strong impact on cell-based bioelectronic applications. We present a new type of microelectrode array chip featuring a nanoporous alumina interface. The chip is fabricated in a combination of top-down and bottom-up processes using state-of-the-art clean room technology and self-assembled generation of nanopores by aluminum anodization. The electrode characteristics are investigated in phosphate buffered saline as well as under cell culture conditions. We show that the modified microelectrodes exhibit decreased impedance compared to planar microelectrodes, which is caused by a nanostructuring effect of the underlying gold during anodization. The stability and biocompatibility of the device are demonstrated by measuring action potentials from cardiomyocyte-like cells growing on top of the chip. Cross sections of the cell-surface interface reveal that the cell membrane seals the nanoporous alumina layer without bending into the sub-50 nm apertures. The nanoporous microelectrode array device may be used as a platform for combining extracellular recording of cell activity with stimulating topographical cues.

A Prestressed Cable Network Model of the Adherent Cell Cytoskeleton

PubMed Central

Coughlin, Mark F.; Stamenović, Dimitrije

2003-01-01

A prestressed cable network is used to model the deformability of the adherent cell actin cytoskeleton. The overall and microstructural model geometries and cable mechanical properties were assigned values based on observations from living cells and mechanical measurements on isolated actin filaments, respectively. The models were deformed to mimic cell poking (CP), magnetic twisting cytometry (MTC) and magnetic bead microrheometry (MBM) measurements on living adherent cells. The models qualitatively and quantitatively captured the fibroblast cell response to the deformation imposed by CP while exhibiting only some qualitative features of the cell response to MTC and MBM. The model for CP revealed that the tensed peripheral actin filaments provide the key resistance to indentation. The actin filament tension that provides mechanical integrity to the network was estimated at ∼158 pN, and the nonlinear mechanical response during CP originates from filament kinematics. The MTC and MBM simulations revealed that the model is incomplete, however, these simulations show cable tension as a key determinant of the model response. PMID:12547813

A prestressed cable network model of the adherent cell cytoskeleton.

PubMed

Coughlin, Mark F; Stamenović, Dimitrije

2003-02-01

A prestressed cable network is used to model the deformability of the adherent cell actin cytoskeleton. The overall and microstructural model geometries and cable mechanical properties were assigned values based on observations from living cells and mechanical measurements on isolated actin filaments, respectively. The models were deformed to mimic cell poking (CP), magnetic twisting cytometry (MTC) and magnetic bead microrheometry (MBM) measurements on living adherent cells. The models qualitatively and quantitatively captured the fibroblast cell response to the deformation imposed by CP while exhibiting only some qualitative features of the cell response to MTC and MBM. The model for CP revealed that the tensed peripheral actin filaments provide the key resistance to indentation. The actin filament tension that provides mechanical integrity to the network was estimated at approximately 158 pN, and the nonlinear mechanical response during CP originates from filament kinematics. The MTC and MBM simulations revealed that the model is incomplete, however, these simulations show cable tension as a key determinant of the model response.

Abnormal mural cell recruitment in lymphatic capillaries: a common pathological feature in chronic lymphedematous skin?

PubMed

Yu, Zi-You; Sun, Di; Luo, Yi; Liu, Ning-Fei

2016-10-01

This study aimed to explore the structural and functional characteristics of dermal lymphatic capillaries in patients with chronic LE, specifically focused on the mural cells that are associated with skin lymphatics. Forty-four patients (30 primary LE and 14 secondary LE) and eight healthy controls were enrolled in this study. Genetic analysis of the FOXC2 was performed in 18 patients with primary LE. Full-thickness skin was excised and immunohistologically stained for podoplanin and α-SMA. The proportions of α-SMA + Lv (α-SMA + Lv%) were calculated. Lymphatic vascular function was assessed by indocyanine green lymphography. Analysis of FOXC2 revealed two mutations in two patients with LDs. Histologically, thirty-nine patients exhibited increased α-SMA + mural cell coverage of lymphatic capillaries. The α-SMA + Lv% values in the superficial and deep dermis in patients with primary and secondary LE were significantly higher than in the control group. Compared with imaging findings in healthy limbs, in which the collecting lymphatics were clearly visualized, lymphedematous extremities all exhibited dermal backflow. Abnormal recruitment of mural cells in dermal lymphatic capillaries is a common pathological event in chronic LE, and may play a role in disease evolution. © 2016 John Wiley & Sons Ltd.

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

Hoekstra, M.F.; Ou, A.C.; DeMaggio, A.J.

In simple eukaryotes, protein kinases regulate mitotic and meiotic cell cycles, the response to polypeptide pheromones, and the initiation of nuclear DNA synthesis. The protein HRR25 from the budding yeast Saccharomyces cerevisiae was defined by the mutation hrr25-1. This mutation resulted in sensitivity to continuous expression of the HO double-strand endonuclease, to methyl methanesulfonate, and to x-irradiation. Homozygotes of hrr25-1 were unable to sporulate and disruption and deletion of HRR25 interfered with mitotic and meiotic cell division. Sequence analysis revealed two distinctive regions in the protein. The NH{sub 2}-terminus of HRR25 contains the hallmark features of protein kinases, whereas themore » COOH-terminus is rich in proline and glutamine. Mutations in HRR25 at conserved residues found in all protein kinases inactivated the gene, and these mutants exhibited the hrr25 null phenotypes. Taken together, the hrr25 mutant phenotypes and the features of the gene product indicate that HRR25 is a distinctive member of the protein kinase superfamily.« less

Label-free sensor for automatic identification of erythrocytes using digital in-line holographic microscopy and machine learning.

PubMed

Go, Taesik; Byeon, Hyeokjun; Lee, Sang Joon

2018-04-30

Cell types of erythrocytes should be identified because they are closely related to their functionality and viability. Conventional methods for classifying erythrocytes are time consuming and labor intensive. Therefore, an automatic and accurate erythrocyte classification system is indispensable in healthcare and biomedical fields. In this study, we proposed a new label-free sensor for automatic identification of erythrocyte cell types using a digital in-line holographic microscopy (DIHM) combined with machine learning algorithms. A total of 12 features, including information on intensity distributions, morphological descriptors, and optical focusing characteristics, is quantitatively obtained from numerically reconstructed holographic images. All individual features for discocytes, echinocytes, and spherocytes are statistically different. To improve the performance of cell type identification, we adopted several machine learning algorithms, such as decision tree model, support vector machine, linear discriminant classification, and k-nearest neighbor classification. With the aid of these machine learning algorithms, the extracted features are effectively utilized to distinguish erythrocytes. Among the four tested algorithms, the decision tree model exhibits the best identification performance for the training sets (n = 440, 98.18%) and test sets (n = 190, 97.37%). This proposed methodology, which smartly combined DIHM and machine learning, would be helpful for sensing abnormal erythrocytes and computer-aided diagnosis of hematological diseases in clinic. Copyright © 2017 Elsevier B.V. All rights reserved.

Strain-enhanced stress relaxation impacts nonlinear elasticity in collagen gels

PubMed Central

Nam, Sungmin; Hu, Kenneth H.; Chaudhuri, Ovijit

2016-01-01

The extracellular matrix (ECM) is a complex assembly of structural proteins that provides physical support and biochemical signaling to cells in tissues. The mechanical properties of the ECM have been found to play a key role in regulating cell behaviors such as differentiation and malignancy. Gels formed from ECM protein biopolymers such as collagen or fibrin are commonly used for 3D cell culture models of tissue. One of the most striking features of these gels is that they exhibit nonlinear elasticity, undergoing strain stiffening. However, these gels are also viscoelastic and exhibit stress relaxation, with the resistance of the gel to a deformation relaxing over time. Recent studies have suggested that cells sense and respond to both nonlinear elasticity and viscoelasticity of ECM, yet little is known about the connection between nonlinear elasticity and viscoelasticity. Here, we report that, as strain is increased, not only do biopolymer gels stiffen but they also exhibit faster stress relaxation, reducing the timescale over which elastic energy is dissipated. This effect is not universal to all biological gels and is mediated through weak cross-links. Mechanistically, computational modeling and atomic force microscopy (AFM) indicate that strain-enhanced stress relaxation of collagen gels arises from force-dependent unbinding of weak bonds between collagen fibers. The broader effect of strain-enhanced stress relaxation is to rapidly diminish strain stiffening over time. These results reveal the interplay between nonlinear elasticity and viscoelasticity in collagen gels, and highlight the complexity of the ECM mechanics that are likely sensed through cellular mechanotransduction. PMID:27140623

Stabilization of gene expression and cell morphology after explant recycling during fin explant culture in goldfish

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

Chenais, Nathalie; Lareyre, Jean-Jacques; Le Bail, Pierre-Yves

The development of fin primary cell cultures for in vitro cellular and physiological studies is hampered by slow cell outgrowth, low proliferation rate, poor viability, and sparse cell characterization. Here, we investigated whether the recycling of fresh explants after a first conventional culture could improve physiological stability and sustainability of the culture. The recycled explants were able to give a supplementary cell culture showing faster outgrowth, cleaner cell layers and higher net cell production. The cells exhibited a highly stabilized profile for marker gene expression including a low cytokeratin 49 (epithelial marker) and a high collagen 1a1 (mesenchymal marker) expression.more » Added to the cell spindle-shaped morphology, motility behavior, and actin organization, this suggests that the cells bore stable mesenchymal characteristics. This contrast with the time-evolving expression pattern observed in the control fresh explants during the first 2 weeks of culture: a sharp decrease in cytokeratin 49 expression was concomitant with a gradual increase in col1a1. We surmise that such loss of epithelial features for the benefit of mesenchymal ones was triggered by an epithelial to mesenchymal transition (EMT) process or by way of a progressive population replacement process. Overall, our findings provide a comprehensive characterization of this new primary culture model bearing mesenchymal features and whose stability over culture time makes those cells good candidates for cell reprogramming prior to nuclear transfer, in a context of fish genome preservation. - Highlights: • Recycled fin explants outgrow cells bearing stable mesenchymal traits. • Cell production and quality is enhanced in the recycled explant culture system. • Fresh fin primary culture is highly variable and loose epithelial traits over time.« less

Peripheral T-cell lymphomas of follicular helper T-cell type frequently display an aberrant CD3(-/dim)CD4(+) population by flow cytometry: an important clue to the diagnosis of a Hodgkin lymphoma mimic.

PubMed

Alikhan, Mir; Song, Joo Y; Sohani, Aliyah R; Moroch, Julien; Plonquet, Anne; Duffield, Amy S; Borowitz, Michael J; Jiang, Liuyan; Bueso-Ramos, Carlos; Inamdar, Kedar; Menon, Madhu P; Gurbuxani, Sandeep; Chan, Ernest; Smith, Sonali M; Nicolae, Alina; Jaffe, Elaine S; Gaulard, Philippe; Venkataraman, Girish

2016-10-01

Nodal follicular helper T-cell-derived lymphoproliferations (specifically the less common peripheral T-cell lymphomas of follicular type) exhibit a spectrum of histologic features that may mimic reactive hyperplasia or Hodgkin lymphoma. Even though angioimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma of follicular type share a common biologic origin from follicular helper T-cells and their morphology has been well characterized, flow cytometry of peripheral T-cell lymphomas of follicular type has not been widely discussed as a tool for identifying this reactive hyperplasia/Hodgkin lymphoma mimic. We identified 10 peripheral T-cell lymphomas of follicular type with available flow cytometry data from five different institutions, including two cases with peripheral blood evaluation. For comparison, we examined flow cytometry data for 8 classical Hodgkin lymphomas (including 1 lymphocyte-rich classical Hodgkin lymphoma), 15 nodular lymphocyte predominant Hodgkin lymphomas, 15 angioimmunoblastic T-cell lymphomas, and 26 reactive nodes. Lymph node histology and flow cytometry data were reviewed, specifically for the presence of a CD3(-/dim)CD4(+) aberrant T-cell population (described in angioimmunoblastic T-cell lymphomas), besides other T-cell aberrancies. Nine of 10 (90%) peripheral T-cell lymphomas of follicular type showed a CD3(-/dim)CD4(+) T-cell population constituting 29.3% (range 7.9-62%) of all lymphocytes. Five of 10 (50%) had nodular lymphocyte predominant Hodgkin lymphoma or lymphocyte-rich classical Hodgkin lymphoma-like morphology with scattered Hodgkin-like cells that expressed CD20, CD30, CD15, and MUM1. Three cases had a nodular growth pattern and three others exhibited a perifollicular growth pattern without Hodgkin-like cells. Epstein-Barr virus was positive in 1 of 10 cases (10%). PCR analysis showed clonal T-cell receptor gamma gene rearrangement in all 10 peripheral T-cell lymphomas of follicular type. By flow cytometry, 11 of 15 (73.3%) angioimmunoblastic T-cell lymphomas showed the CD3(-/dim)CD4(+) population (mean: 19.5%, range: 3-71.8%). Using a threshold of 3% for CD3(-/dim)CD4(+) T cells, all 15 nodular lymphocyte predominant Hodgkin lymphoma controls and 8 classical Hodgkin lymphomas were negative (Mann-Whitney P=0.01, F-PTCL vs Hodgkin lymphomas), as were 25 of 26 reactive lymph nodes. The high frequency of CD3(-/dim)CD4(+) aberrant T cells is similar in angioimmunoblastic T-cell lymphomas and peripheral T-cell lymphomas of follicular type, and is a useful feature in distinguishing peripheral T-cell lymphomas of follicular type from morphologic mimics such as reactive hyperplasia or Hodgkin lymphoma.

Flat Epithelial Atypia of the Breast.

PubMed

Collins, Laura C

2009-06-01

Lesions of the breast characterized by enlarged terminal duct lobular units lined by columnar epithelial cells are being encountered increasingly in breast biopsy specimens. Some of these lesions feature cuboidal to columnar epithelial cells in which the lining cells exhibit cytologic atypia. The role of these lesions (recently designated "flat epithelial atypia" [FEA]) in breast tumor progression is still emerging. FEA commonly coexists with well-developed examples of atypical ductal hyperplasia, low-grade ductal carcinoma in situ, lobular neoplasia, and tubular carcinoma. These findings and those of recent genetic studies suggest that FEA is a neoplastic lesion that may represent a precursor to or the earliest morphologic manifestation of ductal carcinoma in situ. Additional studies are needed to better understand the biologic nature and clinical significance of these lesions. Copyright © 2009 Elsevier Inc. All rights reserved.

Perivascular epithelioid cell tumor (PEComa) of the uterus with aggressive behavior at presentation.

PubMed

Liu, Jing-Lan; Lin, Yueh-Min; Lin, Ming-Chieh; Yeh, Kun-Tu; Hsu, Jui-Chang; Chin, Chih-Jung

2009-01-01

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor composed of histologically and immunohistochemically distinctive perivascular epithelioid cells (PECs). Both benign and malignant tumors have been identified, but the criteria for diagnosis of malignancy have not been fully established due to the rarity of the tumor. We report on a case of uterine PEComa in a 33-year old woman with lymph node metastasis at presentation. The tumor had the characteristic histologic features of PEComa with cytologic atypia, mitotic activity of 2/10 high power field (HPF), and necrosis; it exhibited immunopositivity for HMB-45, calponin and desmin and was negative for melan-A. The patient received neoadjuvant chemotherapy, debulking surgery and adjuvant chemotherapy. No evidence of recurrence or metastasis was apparent 8 months after surgery.

Two cases of perivascular epithelioid cell tumor of the uterus: clinical, radiological and pathological diagnostic challenge.

PubMed

Kwon, Byung Su; Suh, Dong Soo; Lee, Nam Kyung; Song, Yong Jung; Choi, Kyung Un; Kim, Ki Hyung

2017-03-07

Perivascular epithelioid cell tumor (PEComa) is a rare subtype of mesenchymal origin tumor composed of epithelioid cells which exhibits immunohistochemical co-expressions of melanocytic markers and smooth muscle markers. In the first case, malignant uterine PEComa with vaginal and multiple lung metastasis was misdiagnosed preoperatively as uterine leiomyosarcoma despite a preoperative punch biopsy and immunohistochemical analysis of the metastatic vaginal mass. In the second case, synchronous uterine PEComa showing benign histology with lymph node involvement was incidentally detected after a staging operation for ovarian cancer. Definitive diagnosis of uterine PEComa was achieved only after hysterectomy despite preoperative assessment with pelvic magnetic resonance imaging and punch biopsy of metastatic lesion. The authors report two rare cases of uterine PEComa diagnosed postoperatively based on the morphologic and immunohistochemical features.

Inductive phenomena at low frequencies in impedance spectra of proton exchange membrane fuel cells - A review

NASA Astrophysics Data System (ADS)

Pivac, Ivan; Barbir, Frano

2016-09-01

The results of electrochemical impedance spectroscopy of proton exchange membrane (PEM) fuel cells may exhibit inductive phenomena at low frequencies. The occurrence of inductive features at high frequencies is explained by the cables and wires of the test system. However, explanation of inductive loop at low frequencies requires a more detailed study. This review paper discusses several possible causes of such inductive behavior in PEM fuel cells, such as side reactions with intermediate species, carbon monoxide poisoning, and water transport, also as their equivalent circuit representations. It may be concluded that interpretation of impedance spectra at low frequencies is still ambiguous, and that better equivalent circuit models are needed with clearly defined physical meaning of each of the circuit elements.

A novel mutation in the Norrie disease gene.

PubMed

Ott, S; Patel, R J; Appukuttan, B; Wang, X; Stout, J T

2000-04-01

Norrie disease is an X-linked recessive disorder characterized by congenital blindness and in some cases mental retardation and deafness.(1) The variability of signs among patients often complicates diagnosis. Signs such as an ocular pseudoglioma, progressive deafness, and mental disturbance are considered classic features.(2) Only one third of patients with Norrie disease have sensorineural deafness, and approximately one half of the affected individuals exhibit mental retardation, often with psychotic features.(3) Histologic analysis has suggested that retinal dysgenesis occurs early in eye development and involves cells in the inner wall of the optic cup.(4) The gene associated with Norrie disease was identified in 1992. (5,6) We report a novel mutation identified in a patient in whom Norrie disease was diagnosed.

Aqueous Black Colloids of Reticular Nanostructured Gold

NASA Astrophysics Data System (ADS)

Stanca, S. E.; Fritzsche, W.; Dellith, J.; Froehlich, F.; Undisz, A.; Deckert, V.; Krafft, C.; Popp, J.

2015-01-01

Since ancient times, noble gold has continuously contributed to several aspects of life from medicine to electronics. It perpetually reveals its new features. We report the finding of a unique form of gold, reticular nanostructured gold (RNG), as an aqueous black colloid, for which we present a one-step synthesis. The reticules consist of gold crystals that interconnect to form compact strands. RNG exhibits high conductivity and low reflection, and these features, coupled with the high specific surface area of the material, could prove valuable for applications in electronics and catalysis. Due to high absorption throughout the visible and infrared domain, RNG has the potential to be applied in the construction of sensitive solar cells or as a substrate for Raman spectroscopy.

MRG15 Regulates Embryonic Development and Cell Proliferation

PubMed Central

Tominaga, Kaoru; Kirtane, Bhakti; Jackson, James G.; Ikeno, Yuji; Ikeda, Takayoshi; Hawks, Christina; Smith, James R.; Matzuk, Martin M.; Pereira-Smith, Olivia M.

2005-01-01

MRG15 is a highly conserved protein, and orthologs exist in organisms from yeast to humans. MRG15 associates with at least two nucleoprotein complexes that include histone acetyltransferases and/or histone deacetylases, suggesting it is involved in chromatin remodeling. To study the role of MRG15 in vivo, we generated knockout mice and determined that the phenotype is embryonic lethal, with embryos and the few stillborn pups exhibiting developmental delay. Immunohistochemical analysis indicates that apoptosis in Mrg15−/− embryos is not increased compared with wild-type littermates. However, the number of proliferating cells is significantly reduced in various tissues of the smaller null embryos compared with control littermates. Cell proliferation defects are also observed in Mrg15−/− mouse embryonic fibroblasts. The hearts of the Mrg15−/− embryos exhibit some features of hypertrophic cardiomyopathy. The increase in size of the cardiomyocytes is most likely a response to decreased growth of the cells. Mrg15−/− embryos appeared pale, and microarray analysis revealed that α-globin gene expression was decreased in null versus wild-type embryos. We determined by chromatin immunoprecipitation that MRG15 was recruited to the α-globin promoter during dimethyl sulfoxide-induced mouse erythroleukemia cell differentiation. These findings demonstrate that MRG15 has an essential role in embryonic development via chromatin remodeling and transcriptional regulation. PMID:15798182

Phenotypes and Karyotypes of Human Malignant Mesothelioma Cell Lines

PubMed Central

Relan, Vandana; Morrison, Leanne; Parsonson, Kylie; Clarke, Belinda E.; Duhig, Edwina E.; Windsor, Morgan N.; Matar, Kevin S.; Naidoo, Rishendran; Passmore, Linda; McCaul, Elizabeth; Courtney, Deborah; Yang, Ian A.; Fong, Kwun M.; Bowman, Rayleen V.

2013-01-01

Background Malignant mesothelioma is an aggressive tumour of serosal surfaces most commonly pleura. Characterised cell lines represent a valuable tool to study the biology of mesothelioma. The aim of this study was to develop and biologically characterise six malignant mesothelioma cell lines to evaluate their potential as models of human malignant mesothelioma. Methods Five lines were initiated from pleural biopsies, and one from pleural effusion of patients with histologically proven malignant mesothelioma. Mesothelial origin was assessed by standard morphology, Transmission Electron Microscopy (TEM) and immunocytochemistry. Growth characteristics were assayed using population doubling times. Spectral karyotyping was performed to assess chromosomal abnormalities. Authentication of donor specific derivation was undertaken by DNA fingerprinting using a panel of SNPs. Results Most of cell lines exhibited spindle cell shape, with some retaining stellate shapes. At passage 2 to 6 all lines stained positively for calretinin and cytokeratin 19, and demonstrated capacity for anchorage-independent growth. At passage 4 to 16, doubling times ranged from 30–72 hours, and on spectral karyotyping all lines exhibited numerical chromosomal abnormalities ranging from 41 to 113. Monosomy of chromosomes 8, 14, 22 or 17 was observed in three lines. One line displayed four different karyotypes at passage 8, but only one karyotype at passage 42, and another displayed polyploidy at passage 40 which was not present at early passages. At passages 5–17, TEM showed characteristic features of mesothelioma ultrastructure in all lines including microvilli and tight intercellular junctions. Conclusion These six cell lines exhibit varying cell morphology, a range of doubling times, and show diverse passage-dependent structural chromosomal changes observed in malignant tumours. However they retain characteristic immunocytochemical protein expression profiles of mesothelioma during maintenance in artificial culture systems. These characteristics support their potential as in vitro model systems for studying cellular, molecular and genetic aspects of mesothelioma. PMID:23516439

Pancreatic cancer cell lines as patient-derived avatars: genetic characterisation and functional utility.

PubMed

Knudsen, Erik S; Balaji, Uthra; Mannakee, Brian; Vail, Paris; Eslinger, Cody; Moxom, Christopher; Mansour, John; Witkiewicz, Agnieszka K

2018-03-01

Pancreatic ductal adenocarcinoma (PDAC) is a therapy recalcitrant disease with the worst survival rate of common solid tumours. Preclinical models that accurately reflect the genetic and biological diversity of PDAC will be important for delineating features of tumour biology and therapeutic vulnerabilities. 27 primary PDAC tumours were employed for genetic analysis and development of tumour models. Tumour tissue was used for derivation of xenografts and cell lines. Exome sequencing was performed on the originating tumour and developed models. RNA sequencing, histological and functional analyses were employed to determine the relationship of the patient-derived models to clinical presentation of PDAC. The cohort employed captured the genetic diversity of PDAC. From most cases, both cell lines and xenograft models were developed. Exome sequencing confirmed preservation of the primary tumour mutations in developed cell lines, which remained stable with extended passaging. The level of genetic conservation in the cell lines was comparable to that observed with patient-derived xenograft (PDX) models. Unlike historically established PDAC cancer cell lines, patient-derived models recapitulated the histological architecture of the primary tumour and exhibited metastatic spread similar to that observed clinically. Detailed genetic analyses of tumours and derived models revealed features of ex vivo evolution and the clonal architecture of PDAC. Functional analysis was used to elucidate therapeutic vulnerabilities of relevance to treatment of PDAC. These data illustrate that with the appropriate methods it is possible to develop cell lines that maintain genetic features of PDAC. Such models serve as important substrates for analysing the significance of genetic variants and create a unique biorepository of annotated cell lines and xenografts that were established simultaneously from same primary tumour. These models can be used to infer genetic and empirically determined therapeutic sensitivities that would be germane to the patient. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Isolation and characterization of string-forming female germline stem cells from ovaries of neonatal mice.

PubMed

Liu, Jing; Shang, Dantong; Xiao, Yao; Zhong, Pei; Cheng, Hanhua; Zhou, Rongjia

2017-09-29

Germline stem cells are essential in the generation of both male and female gametes. In mammals, the male testis produces sperm throughout the entire lifetime, facilitated by testicular germline stem cells. Oocyte renewal ceases in postnatal or adult life in mammalian females, suggesting that germline stem cells are absent from the mammalian ovary. However, studies in mice, rats, and humans have recently provided evidence for ovarian female germline stem cells (FGSCs). A better understanding of the role of FGSCs in ovaries could help improve fertility treatments. Here, we developed a rapid and efficient method for isolating FGSCs from ovaries of neonatal mice. Notably, our FGSC isolation method could efficiently isolate on average 15 cell "strings" per ovary from mice at 1-3 days postpartum. FGSCs isolated from neonatal mice displayed the string-forming cell configuration at mitosis ( i.e. a "stringing" FGSC (sFGSC) phenotype) and a disperse phenotype in postnatal mice. We also found that sFGSCs undergo vigorous mitosis especially at 1-3 days postpartum. After cell division, the sFGSC membranes tended to be connected to form sFGSCs. Moreover, F-actin filaments exhibited a cell-cortex distribution in sFGSCs, and E-cadherin converged in cell-cell connection regions, resulting in the string-forming morphology. Our new method provides a platform for isolating FGSCs from the neonatal ovary, and our findings indicate that FGCSs exhibit string-forming features in neonatal mice. The sFGSCs represent a valuable resource for analysis of ovary function and an in vitro model for future clinical use to address ovarian dysfunction. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Renal cell tumors with clear cell histology and intact VHL and chromosome 3p: a histological review of tumors from the Cancer Genome Atlas database.

PubMed

Favazza, Laura; Chitale, Dhananjay A; Barod, Ravi; Rogers, Craig G; Kalyana-Sundaram, Shanker; Palanisamy, Nallasivam; Gupta, Nilesh S; Williamson, Sean R

2017-11-01

Clear cell renal cell carcinoma is by far the most common form of kidney cancer; however, a number of histologically similar tumors are now recognized and considered distinct entities. The Cancer Genome Atlas published data set was queried (http://cbioportal.org) for clear cell renal cell carcinoma tumors lacking VHL gene mutation and chromosome 3p loss, for which whole-slide images were reviewed. Of the 418 tumors in the published Cancer Genome Atlas clear cell renal cell carcinoma database, 387 had VHL mutation, copy number loss for chromosome 3p, or both (93%). Of the remaining, 27/31 had whole-slide images for review. One had 3p loss based on karyotype but not sequencing, and three demonstrated VHL promoter hypermethylation. Nine could be reclassified as distinct or emerging entities: translocation renal cell carcinoma (n=3), TCEB1 mutant renal cell carcinoma (n=3), papillary renal cell carcinoma (n=2), and clear cell papillary renal cell carcinoma (n=1). Of the remaining, 6 had other clear cell renal cell carcinoma-associated gene alterations (PBRM1, SMARCA4, BAP1, SETD2), leaving 11 specimens, including 2 high-grade or sarcomatoid renal cell carcinomas and 2 with prominent fibromuscular stroma (not TCEB1 mutant). One of the remaining tumors exhibited gain of chromosome 7 but lacked histological features of papillary renal cell carcinoma. Two tumors previously reported to harbor TFE3 gene fusions also exhibited VHL mutation, chromosome 3p loss, and morphology indistinguishable from clear cell renal cell carcinoma, the significance of which is uncertain. In summary, almost all clear cell renal cell carcinomas harbor VHL mutation, 3p copy number loss, or both. Of tumors with clear cell histology that lack these alterations, a subset can now be reclassified as other entities. Further study will determine whether additional entities exist, based on distinct genetic pathways that may have implications for treatment.

A novel, long-lived, and highly engraftable immunodeficient mouse model of mucopolysaccharidosis type I.

PubMed

Mendez, Daniel C; Stover, Alexander E; Rangel, Anthony D; Brick, David J; Nethercott, Hubert E; Torres, Marissa A; Khalid, Omar; Wong, Andrew Ms; Cooper, Jonathan D; Jester, James V; Monuki, Edwin S; McGuire, Cian; Le, Steven Q; Kan, Shih-Hsin; Dickson, Patricia I; Schwartz, Philip H

2015-01-01

Mucopolysaccharidosis type I (MPS I) is an inherited α-L-iduronidase (IDUA, I) deficiency in which glycosaminoglycan (GAG) accumulation causes progressive multisystem organ dysfunction, neurological impairment, and death. Current MPS I mouse models, based on a NOD/SCID (NS) background, are short-lived, providing a very narrow window to assess the long-term efficacy of therapeutic interventions. They also develop thymic lymphomas, making the assessment of potential tumorigenicity of human stem cell transplantation problematic. We therefore developed a new MPS I model based on a NOD/SCID/Il2rγ (NSG) background. This model lives longer than 1 year and is tumor-free during that time. NSG MPS I (NSGI) mice exhibit the typical phenotypic features of MPS I including coarsened fur and facial features, reduced/abnormal gait, kyphosis, and corneal clouding. IDUA is undetectable in all tissues examined while GAG levels are dramatically higher in most tissues. NSGI brain shows a significant inflammatory response and prominent gliosis. Neurological MPS I manifestations are evidenced by impaired performance in behavioral tests. Human neural and hematopoietic stem cells were found to readily engraft, with human cells detectable for at least 1 year posttransplantation. This new MPS I model is thus suitable for preclinical testing of novel pluripotent stem cell-based therapy approaches.

A novel, long-lived, and highly engraftable immunodeficient mouse model of mucopolysaccharidosis type I

PubMed Central

Mendez, Daniel C; Stover, Alexander E; Rangel, Anthony D; Brick, David J; Nethercott, Hubert E; Torres, Marissa A; Khalid, Omar; Wong, Andrew MS; Cooper, Jonathan D; Jester, James V; Monuki, Edwin S; McGuire, Cian; Le, Steven Q; Kan, Shih-hsin; Dickson, Patricia I; Schwartz, Philip H

2015-01-01

Mucopolysaccharidosis type I (MPS I) is an inherited α-L-iduronidase (IDUA, I) deficiency in which glycosaminoglycan (GAG) accumulation causes progressive multisystem organ dysfunction, neurological impairment, and death. Current MPS I mouse models, based on a NOD/SCID (NS) background, are short-lived, providing a very narrow window to assess the long-term efficacy of therapeutic interventions. They also develop thymic lymphomas, making the assessment of potential tumorigenicity of human stem cell transplantation problematic. We therefore developed a new MPS I model based on a NOD/SCID/Il2rγ (NSG) background. This model lives longer than 1 year and is tumor-free during that time. NSG MPS I (NSGI) mice exhibit the typical phenotypic features of MPS I including coarsened fur and facial features, reduced/abnormal gait, kyphosis, and corneal clouding. IDUA is undetectable in all tissues examined while GAG levels are dramatically higher in most tissues. NSGI brain shows a significant inflammatory response and prominent gliosis. Neurological MPS I manifestations are evidenced by impaired performance in behavioral tests. Human neural and hematopoietic stem cells were found to readily engraft, with human cells detectable for at least 1 year posttransplantation. This new MPS I model is thus suitable for preclinical testing of novel pluripotent stem cell-based therapy approaches. PMID:26052536

Intraclonal Cell Expansion and Selection Driven by B Cell Receptor in Chronic Lymphocytic Leukemia

PubMed Central

Colombo, Monica; Cutrona, Giovanna; Reverberi, Daniele; Fabris, Sonia; Neri, Antonino; Fabbi, Marina; Quintana, Giovanni; Quarta, Giovanni; Ghiotto, Fabio; Fais, Franco; Ferrarini, Manlio

2011-01-01

The mutational status of the immunoglobulin heavy-chain variable region (IGHV) genes utilized by chronic lymphocytic leukemia (CLL) clones defines two disease subgroups. Patients with unmutated IGHV have a more aggressive disease and a worse outcome than patients with cells having somatic IGHV gene mutations. Moreover, up to 30% of the unmutated CLL clones exhibit very similar or identical B cell receptors (BcR), often encoded by the same IG genes. These “stereotyped” BcRs have been classified into defined subsets. The presence of an IGHV gene somatic mutation and the utilization of a skewed gene repertoire compared with normal B cells together with the expression of stereotyped receptors by unmutated CLL clones may indicate stimulation/selection by antigenic epitopes. This antigenic stimulation may occur prior to or during neoplastic transformation, but it is unknown whether this stimulation/selection continues after leukemogenesis has ceased. In this study, we focused on seven CLL cases with stereotyped BcR Subset #8 found among a cohort of 700 patients; in six, the cells expressed IgG and utilized IGHV4-39 and IGKV1-39/IGKV1D-39 genes, as reported for Subset #8 BcR. One case exhibited special features, including expression of IgM or IgG by different subclones consequent to an isotype switch, allelic inclusion at the IGH locus in the IgM-expressing cells and a particular pattern of cytogenetic lesions. Collectively, the data indicate a process of antigenic stimulation/selection of the fully transformed CLL cells leading to the expansion of the Subset #8 IgG-bearing subclone. PMID:21541442

TFE3 break-apart FISH has a higher sensitivity for Xp11.2 translocation-associated renal cell carcinoma compared with TFE3 or cathepsin K immunohistochemical staining alone: expanding the morphologic spectrum.

PubMed

Rao, Qiu; Williamson, Sean R; Zhang, Shaobo; Eble, John N; Grignon, David J; Wang, Mingsheng; Zhou, Xiao-Jun; Huang, Wenbin; Tan, Puay-Hoon; Maclennan, Gregory T; Cheng, Liang

2013-06-01

Renal cell carcinoma (RCC) associated with Xp11.2 translocation is uncommon, characterized by several different translocations involving the TFE3 gene. We assessed the utility of break-apart fluorescence in situ hybridization (FISH) in establishing the diagnosis for suspected or unclassified cases with negative or equivocal TFE3 immunostaining by analyzing 24 renal cancers with break-apart TFE3 FISH and comparing the molecular findings with the results of TFE3 and cathepsin K immunostaining in the same tumors. Ten tumors were originally diagnosed as Xp11.2 RCC on the basis of positive TFE3 immunostaining, and 14 were originally considered unclassified RCCs with negative or equivocal TFE3 staining, but with a range of features suspicious for Xp11.2 RCC. Seventeen cases showed TFE3 rearrangement associated with Xp11.2 translocation by FISH, including all 13 tumors with moderate or strong TFE3 (n=10) or cathepsin K (n=7) immunoreactivity. FISH-positive cases showed negative or equivocal immunoreactivity for TFE3 or cathepsin K in 7 and 10 tumors, respectively (both=3). None had positive immunohistochemistry but negative FISH. Morphologic features were typical for Xp11.2 RCC in 10/17 tumors. Unusual features included 1 melanotic Xp11.2 renal cancer, 1 tumor with mixed features of Xp11.2 RCC and clear cell RCC, and other tumors mimicking clear cell RCC, multilocular cystic RCC, or high-grade urothelial carcinoma. Morphology mimicking high-grade urothelial carcinoma has not been previously reported in these tumors. Psammoma bodies, hyalinized stroma, and intracellular pigment were preferentially identified in FISH-positive cases compared with FISH-negative cases. Our results support the clinical application of a TFE3 break-apart FISH assay for diagnosis and confirmation of Xp11.2 RCC and further expand the histopathologic spectrum of these neoplasms to include tumors with unusual features. A renal tumor with pathologic or clinical features highly suggestive of translocation-associated RCC but exhibiting negative or equivocal TFE3 immunostaining should be evaluated by TFE3 FISH assay to fully assess this possibility.

Persistent neural activity in head direction cells

NASA Technical Reports Server (NTRS)

Taube, Jeffrey S.; Bassett, Joshua P.; Oman, C. M. (Principal Investigator)

2003-01-01

Many neurons throughout the rat limbic system discharge in relation to the animal's directional heading with respect to its environment. These so-called head direction (HD) cells exhibit characteristics of persistent neural activity. This article summarizes where HD cells are found, their major properties, and some of the important experiments that have been conducted to elucidate how this signal is generated. The number of HD and angular head velocity cells was estimated for several brain areas involved in the generation of the HD signal, including the postsubiculum, anterior dorsal thalamus, lateral mammillary nuclei and dorsal tegmental nucleus. The HD cell signal has many features in common with what is known about how neural integration is accomplished in the oculomotor system. The nature of the HD cell signal makes it an attractive candidate for using neural network models to elucidate the signal's underlying mechanisms. The conditions that any network model must satisfy in order to accurately represent how the nervous system generates this signal are highlighted and areas where key information is missing are discussed.

Agarose hydrogel induced MCF-7 and BMG-1 cell line progressive 3D and 3D revert cultures.

PubMed

Subramaniyan, Aishwarya; Ravi, Maddaly

2018-04-01

3D culture systems have enhanced the utility of cancer cell lines as they are considered closer to the in vivo systems. A variety of changes are induced in cells cultured in 3D systems; an apparent and striking feature being the spontaneous acquisition of distinct morphological entities. 3D reverts (3DRs) can be obtained by introducing 3D aggregates in scaffold/matrix-free culture units. It could be seen that the two cell lines used in this study exhibited differences in 3DR structures, though both were cultured on agarose hydrogels. Also, differences in 3DR formation, growth and survival were different. While 3D aggregates of several cell lines have been reported for a variety of studies, there are no studies that describe or utilize 3DRs. 3DRs can provide insights into complex events that can occur in cancer cells; especially as material to study metastasis, migration, and invasion. © 2017 Wiley Periodicals, Inc.

Antitumour Effects of Isocurcumenol Isolated from Curcuma zedoaria Rhizomes on Human and Murine Cancer Cells

PubMed Central

Lakshmi, S.; Padmaja, G.; Remani, P.

2011-01-01

Curcuma zedoaria belonging to the family Zingiberaceae has been used in the traditional system of medicine in India and Southwest Asia in treating many human ailments and is found to possess many biological activities. The rationale of the present study was to isolate, identify, and characterize antitumour principles from the rhizomes of Curcuma zedoaria, to assess its cytotoxic effects on human and murine cancer cells, to determine its apoptosis inducing capacity in cancer cells, and to evaluate its tumour reducing properties in in vivo mice models. Isocurcumenol was characterized as the active compound by spectroscopy and was found to inhibit the proliferation of cancer cells without inducing significant toxicity to the normal cells. Fluorescent staining exhibited the morphological features of apoptosis in the compound-treated cancer cells. In vivo tumour reduction studies revealed that a dose of 35.7 mg/kg body weight significantly reduced the ascitic tumour in DLA-challenged mice and increased the lifespan with respect to untreated control mice. PMID:27429805

Chronic inflammation triggered by the NLRP3 inflammasome in myeloid cells promotes growth plate dysplasia by mesenchymal cells.

PubMed

Wang, Chun; Xu, Can-Xin; Alippe, Yael; Qu, Chao; Xiao, Jianqiu; Schipani, Ernestina; Civitelli, Roberto; Abu-Amer, Yousef; Mbalaviele, Gabriel

2017-07-07

Skeletal complications are common features of neonatal-onset multisystem inflammatory disease (NOMID), a disorder caused by NLRP3-activating mutations. NOMID mice in which NLRP3 is activated globally exhibit several characteristics of the human disease, including systemic inflammation and cartilage dysplasia, but the mechanisms of skeletal manifestations remain unknown. In this study, we find that activation of NLRP3 in myeloid cells, but not mesenchymal cells triggers chronic inflammation, which ultimately, causes growth plate and epiphyseal dysplasia in mice. These responses are IL-1 signaling-dependent, but independent of PARP1, which also functions downstream of NLRP3 and regulates skeletal homeostasis. Mechanistically, inflammation causes severe anemia and hypoxia in the bone environment, yet down-regulates the HIF-1α pathway in chondrocytes, thereby promoting the demise of these cells. Thus, activation of NLRP3 in hematopoietic cells initiates IL-1β-driven paracrine cascades, which promote abnormal growth plate development in NOMID mice.

Computational Model of Population Dynamics Based on the Cell Cycle and Local Interactions

NASA Astrophysics Data System (ADS)

Oprisan, Sorinel Adrian; Oprisan, Ana

2005-03-01

Our study bridges cellular (mesoscopic) level interactions and global population (macroscopic) dynamics of carcinoma. The morphological differences and transitions between well and smooth defined benign tumors and tentacular malignat tumors suggest a theoretical analysis of tumor invasion based on the development of mathematical models exhibiting bifurcations of spatial patterns in the density of tumor cells. Our computational model views the most representative and clinically relevant features of oncogenesis as a fight between two distinct sub-systems: the immune system of the host and the neoplastic system. We implemented the neoplastic sub-system using a three-stage cell cycle: active, dormant, and necrosis. The second considered sub-system consists of cytotoxic active (effector) cells — EC, with a very broad phenotype ranging from NK cells to CTL cells, macrophages, etc. Based on extensive numerical simulations, we correlated the fractal dimensions for carcinoma, which could be obtained from tumor imaging, with the malignat stage. Our computational model was able to also simulate the effects of surgical, chemotherapeutical, and radiotherapeutical treatments.

Changes in the Excitability of Neocortical Neurons in a Mouse Model of Amyotrophic Lateral Sclerosis Are Not Specific to Corticospinal Neurons and Are Modulated by Advancing Disease.

PubMed

Kim, Juhyun; Hughes, Ethan G; Shetty, Ashwin S; Arlotta, Paola; Goff, Loyal A; Bergles, Dwight E; Brown, Solange P

2017-09-13

Cell type-specific changes in neuronal excitability have been proposed to contribute to the selective degeneration of corticospinal neurons in amyotrophic lateral sclerosis (ALS) and to neocortical hyperexcitability, a prominent feature of both inherited and sporadic variants of the disease, but the mechanisms underlying selective loss of specific cell types in ALS are not known. We analyzed the physiological properties of distinct classes of cortical neurons in the motor cortex of hSOD1 G93A mice of both sexes and found that they all exhibit increases in intrinsic excitability that depend on disease stage. Targeted recordings and in vivo calcium imaging further revealed that neurons adapt their functional properties to normalize cortical excitability as the disease progresses. Although different neuron classes all exhibited increases in intrinsic excitability, transcriptional profiling indicated that the molecular mechanisms underlying these changes are cell type specific. The increases in excitability in both excitatory and inhibitory cortical neurons show that selective dysfunction of neuronal cell types cannot account for the specific vulnerability of corticospinal motor neurons in ALS. Furthermore, the stage-dependent alterations in neuronal function highlight the ability of cortical circuits to adapt as disease progresses. These findings show that both disease stage and cell type must be considered when developing therapeutic strategies for treating ALS. SIGNIFICANCE STATEMENT It is not known why certain classes of neurons preferentially die in different neurodegenerative diseases. It has been proposed that the enhanced excitability of affected neurons is a major contributor to their selective loss. We show using a mouse model of amyotrophic lateral sclerosis (ALS), a disease in which corticospinal neurons exhibit selective vulnerability, that changes in excitability are not restricted to this neuronal class and that excitability does not increase monotonically with disease progression. Moreover, although all neuronal cell types tested exhibited abnormal functional properties, analysis of their gene expression demonstrated cell type-specific responses to the ALS-causing mutation. These findings suggest that therapies for ALS may need to be tailored for different cell types and stages of disease. Copyright © 2017 the authors 0270-6474/17/379038-17$15.00/0.

Loss of carbonic anhydrase XII function in individuals with elevated sweat chloride concentration and pulmonary airway disease.

PubMed

Lee, Melissa; Vecchio-Pagán, Briana; Sharma, Neeraj; Waheed, Abdul; Li, Xiaopeng; Raraigh, Karen S; Robbins, Sarah; Han, Sangwoo T; Franca, Arianna L; Pellicore, Matthew J; Evans, Taylor A; Arcara, Kristin M; Nguyen, Hien; Luan, Shan; Belchis, Deborah; Hertecant, Jozef; Zabner, Joseph; Sly, William S; Cutting, Garry R

2016-05-15

Elevated sweat chloride levels, failure to thrive (FTT), and lung disease are characteristic features of cystic fibrosis (CF, OMIM #219700). Here we describe variants in CA12 encoding carbonic anhydrase XII in two pedigrees exhibiting CF-like phenotypes. Exome sequencing of a white American adult diagnosed with CF due to elevated sweat chloride, recurrent hyponatremia, infantile FTT and lung disease identified deleterious variants in each CA12 gene: c.908-1 G>A in a splice acceptor and a novel frameshift insertion c.859_860insACCT. In an unrelated consanguineous Omani family, two children with elevated sweat chloride, infantile FTT, and recurrent hyponatremia were homozygous for a novel missense variant (p.His121Gln). Deleterious CFTR variants were absent in both pedigrees. CA XII protein was localized apically in human bronchiolar epithelia and basolaterally in the reabsorptive duct of human sweat glands. Respiratory epithelial cell RNA from the adult proband revealed only aberrant CA12 transcripts and in vitro analysis showed greatly reduced CA XII protein. Studies of ion transport across respiratory epithelial cells in vivo and in culture revealed intact CFTR-mediated chloride transport in the adult proband. CA XII protein bearing either p.His121Gln or a previously identified p.Glu143Lys missense variant localized to the basolateral membranes of polarized Madin-Darby canine kidney (MDCK) cells, but enzyme activity was severely diminished when assayed at physiologic concentrations of extracellular chloride. Our findings indicate that loss of CA XII function should be considered in individuals without CFTR mutations who exhibit CF-like features in the sweat gland and lung. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Hippocampal “cholinergic interneurons” visualized with the choline acetyltransferase promoter: anatomical distribution, intrinsic membrane properties, neurochemical characteristics, and capacity for cholinergic modulation

PubMed Central

Yi, Feng; Catudio-Garrett, Elizabeth; Gábriel, Robert; Wilhelm, Marta; Erdelyi, Ferenc; Szabo, Gabor; Deisseroth, Karl; Lawrence, Josh

2015-01-01

Release of acetylcholine (ACh) in the hippocampus (HC) occurs during exploration, arousal, and learning. Although the medial septum-diagonal band of Broca (MS-DBB) is the major extrinsic source of cholinergic input to the HC, cholinergic neurons intrinsic to the HC also exist but remain poorly understood. Here, ChAT-tauGFP and ChAT-CRE/Rosa26YFP (ChAT-Rosa) mice were examined in HC. The HC of ChAT-tauGFP mice was densely innervated with GFP-positive axons, often accompanied by large GFP-positive structures, some of which were Neurotrace/DAPI-negative and likely represent large axon terminals. In the HC of ChAT-Rosa mice, ChAT-YFP cells were Neurotrace-positive and more abundant in CA3 and dentate gyrus than CA1 with partial overlap with calretinin/VIP. Moreover, an anti-ChAT antibody consistently showed ChAT immunoreactivity in ChAT-YFP cells from MS-DBB but rarely from HC. Furthermore, ChAT-YFP cells from CA1 stratum radiatum/stratum lacunosum moleculare (SR/SLM) exhibited a stuttering firing phenotype but a delayed firing phenotype in stratum pyramidale (SP) of CA3. Input resistance and capacitance were also different between CA1 SR/LM and CA3 SP ChAT-YFP cells. Bath application of ACh increased firing frequency in all ChAT-YFP cells; however, cholinergic modulation was larger in CA1 SR/SLM than CA3 SP ChAT-YFP cells. Finally, CA3 SP ChAT-YFP cells exhibited a wider AP half-width and weaker cholinergic modulation than YFP-negative CA3 pyramidal cells. Consistent with CRE expression in a subpopulation of principal cells, optogenetic stimulation evoked glutamatergic postsynaptic currents in CA1 SR/SLM interneurons. In conclusion, the presence of fluorescently labeled hippocampal cells common to both ChAT-tauGFP and ChAT-Rosa mice are in good agreement with previous reports on the existence of cholinergic interneurons, but both transgenic mouse lines exhibited unexpected anatomical features that departed considerably from earlier observations. PMID:25798106

Establishment and characterization of a novel osteosarcoma cell line: CHOS.

PubMed

Liu, Yunlu; Feng, Xiaobo; Zhang, Yukun; Jiang, Hongyan; Cai, Xianyi; Yan, Xinxin; Huang, Zengfa; Mo, Fengbo; Yang, Wen; Yang, Cao; Yang, Shuhua; Liu, Xianzhe

2016-12-01

Osteosarcoma has a well-recognized bimodal distribution, with the first peak in adolescence and another in the elderly age-group. The elderly patients have different clinical features and a poorer prognosis as compared to adolescents. To better understand the biological features of osteosarcoma in the elderly population, we established a new human osteosarcoma cell line from a 58-year-old man with primary chondroblastic osteosarcoma. After 6 months of continuous culture in vitro for over 50 passages, an immortalized cell line CHOS was established. The cell line was well-characterized by cytogenetic, biomarker, functional, and histological analyses. The CHOS cells exhibited a spindle-shaped morphology and a doubling time of 36 h. Cytogenetic analysis of CHOS cells revealed the loss of chromosome Y and the gain of chromosome 12. Quantitative real-time polymerase chain reaction (RT-PCR), Western blotting and/or immunofluorescence revealed the expression of chondroblastic, mesenchymal and tumor metastasis markers in the CHOS cells. Compared with the osteosarcoma cell line, the CHOS cells were found to be more sensitive to cisplatin and doxorubicin, but were resistant to methotrexate. The cell line was highly tumorigenic and maintained the histological characteristics and invasive nature of the original tumor. Furthermore, on immunohistochemical analysis, the xenografts and metastases were found to co-express collagen II, aggrecan, vimentin and S100A4 that resembled the original tumor cells. Our results indicate, the potential of CHOS cell line to serve as a useful tool for further studies on the molecular biology of osteosarcoma, especially in the elderly patients. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2116-2125, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Monocyte-lymphocyte fusion induced by the HIV-1 envelope generates functional heterokaryons with an activated monocyte-like phenotype

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

Martínez-Méndez, David; Rivera-Toledo, Evelyn; Ortega, Enrique

Enveloped viruses induce cell-cell fusion when infected cells expressing viral envelope proteins interact with target cells, or through the contact of cell-free viral particles with adjoining target cells. CD4{sup +} T lymphocytes and cells from the monocyte-macrophage lineage express receptors for HIV envelope protein. We have previously reported that lymphoid Jurkat T cells expressing the HIV-1 envelope protein (Env) can fuse with THP-1 monocytic cells, forming heterokaryons with a predominantly myeloid phenotype. This study shows that the expression of monocytic markers in heterokaryons is stable, whereas the expression of lymphoid markers is mostly lost. Like THP-1 cells, heterokaryons exhibited FcγR-dependentmore » phagocytic activity and showed an enhanced expression of the activation marker ICAM-1 upon stimulation with PMA. In addition, heterokaryons showed morphological changes compatible with maturation, and high expression of the differentiation marker CD11b in the absence of differentiation-inducing agents. No morphological change nor increase in CD11b expression were observed when an HIV-fusion inhibitor blocked fusion, or when THP-1 cells were cocultured with Jurkat cells expressing a non-fusogenic Env protein, showing that differentiation was not induced merely by cell-cell interaction but required cell-cell fusion. Inhibition of TLR2/TLR4 signaling by a TIRAP inhibitor greatly reduced the expression of CD11b in heterokaryons. Thus, lymphocyte-monocyte heterokaryons induced by HIV-1 Env are stable and functional, and fusion prompts a phenotype characteristic of activated monocytes via intracellular TLR2/TLR4 signaling. - Highlights: • Jurkat T cells expressing the HIV-1 envelope fuse with THP-1 monocytes. • Heterokaryons display a dominant myeloid phenotype and monocyte function. • Heterokaryons exhibit activation features in the absence of activation agents. • Activation is not due to cell-cell interaction but requires cell-cell fusion. • The activated monocyte-like phenotype is mediated by TLR2/TLR4 signaling.« less

Visualisation of plastid outgrowths in potato (Solanum tuberosum L.) tubers by carboxyfluorescein diacetate staining.

PubMed

Borucki, Wojciech; Bederska, Magdalena; Sujkowska-Rybkowska, Marzena

2015-05-01

We describe two types of plastid outgrowths visualised in potato tubers after carboxyfluorescein diacetate staining. Probable esterase activity of the outgrowths has been demonstrated for the first time ever. Plastid outgrowths were observed in the phelloderm and storage parenchyma cells of red potato (S. tuberosum L. cv. Rosalinde) tubers after administration of carboxyfluorescein diacetate stain. Endogenous esterases cleaved off acetic groups to release membrane-unpermeable green fluorescing carboxyfluorescein which accumulated differentially in particular cell compartments. The intensive green fluorescence of carboxyfluorescein exhibited highly branched stromules (stroma-filled plastid tubular projections of the plastid envelope) and allowed distinguishing them within cytoplasmic strands of the phelloderm cells. Stromules (1) were directed towards the nucleus or (2) penetrated the whole cells through the cytoplasmic bands of highly vacuolated phelloderm cells. Those directed towards the nucleus were flattened and adhered to the nuclear envelope. Stromule-like interconnections between two parts of the same plastids (isthmuses) were also observed. We also documented the formation of another type of the stroma-filled plastid outgrowths, referred to here as protrusions, which differed from previously defined stromules in both morphology and esterase activity. Unlike stromules, the protrusions were found to be associated with developmental processes leading to starch accumulation in the storage parenchyma cells. These results strongly suggest that stromules and protrusions exhibit esterase activity. This has been demonstrated for the first time. Morphological and biochemical features as well as possible functions of stromules and protrusions are discussed below.

Selective modulation of cell response on engineered fractal silicon substrates

PubMed Central

Gentile, Francesco; Medda, Rebecca; Cheng, Ling; Battista, Edmondo; Scopelliti, Pasquale E.; Milani, Paolo; Cavalcanti-Adam, Elisabetta A.; Decuzzi, Paolo

2013-01-01

A plethora of work has been dedicated to the analysis of cell behavior on substrates with ordered topographical features. However, the natural cell microenvironment is characterized by biomechanical cues organized over multiple scales. Here, randomly rough, self-affinefractal surfaces are generated out of silicon,where roughness Ra and fractal dimension Df are independently controlled. The proliferation rates, the formation of adhesion structures, and the morphology of 3T3 murine fibroblasts are monitored over six different substrates. The proliferation rate is maximized on surfaces with moderate roughness (Ra ~ 40 nm) and large fractal dimension (Df ~ 2.4); whereas adhesion structures are wider and more stable on substrates with higher roughness (Ra ~ 50 nm) and lower fractal dimension (Df ~ 2.2). Higher proliferation occurson substrates exhibiting densely packed and sharp peaks, whereas more regular ridges favor adhesion. These results suggest that randomly roughtopographies can selectively modulate cell behavior. PMID:23492898

Synthesis of biocompatible SiO2 coated ZnO quantum dots for cell imaging

NASA Astrophysics Data System (ADS)

Zhang, Min; Wang, Qian; Chen, Haiyan; Gu, Yueqing

2014-09-01

Quantum dots (QDs) is a promising candidate for biomedical imaging. However, the bio-toxicity of traditional quantum dots obstructed their further application seriously. In this work, a simple solution growth method was utilized to synthesize ZnO QDs. However, their self-assemble feature makes them unstable in aqueous solution. Furthermore, (3-Aminopropyl) triethoxysilane was selected as a capping agent to stabilize ZnO QDs and then ZnO@SiO2 nanoparticles were obtained. They dispersed excellently in water and exhibited favorable fluorescence properties owing to the protection of silane. The biocompatability of ZnO@SiO2 nanoparticles was verified by MTT assy. The cell affinity studies demonstrated that ZnO@SiO2 nanoparticles could be uptaken by cells efficiently. Therefore, the as-prepared ZnO@SiO2 nanoparticles is a promising candidate for applications in cell imaging.

Discrete Cu(i) complexes for azide-alkyne annulations of small molecules inside mammalian cells.

PubMed

Miguel-Ávila, Joan; Tomás-Gamasa, María; Olmos, Andrea; Pérez, Pedro J; Mascareñas, José L

2018-02-21

The archetype reaction of "click" chemistry, namely, the copper-promoted azide-alkyne cycloaddition (CuAAC), has found an impressive number of applications in biological chemistry. However, methods for promoting intermolecular annulations of exogenous, small azides and alkynes in the complex interior of mammalian cells, are essentially unknown. Herein we demonstrate that isolated, well-defined copper(i)-tris(triazolyl) complexes featuring designed ligands can readily enter mammalian cells and promote intracellular CuAAC annulations of small, freely diffusible molecules. In addition to simplifying protocols and avoiding the addition of "non-innocent" reductants, the use of these premade copper complexes leads to more efficient processes than with the alternative, in situ made copper species prepared from Cu(ii) sources, tris(triazole) ligands and sodium ascorbate. Under the reaction conditions, the well-defined copper complexes exhibit very good cell penetration properties, and do not present significant toxicities.

Molecular regulation of effector and memory T cell differentiation

PubMed Central

Chang, John T; Wherry, E John; Goldrath, Ananda W

2015-01-01

Immunological memory is a cardinal feature of adaptive immunity and an important goal of vaccination strategies. Here we highlight advances in the understanding of the diverse T lymphocyte subsets that provide acute and long-term protection from infection. These include new insights into the transcription factors, and the upstream ‘pioneering’ factors that regulate their accessibility to key sites of gene regulation, as well as metabolic regulators that contribute to the differentiation of effector and memory subsets; ontogeny and defining characteristics of tissue-resident memory lymphocytes; and origins of the remarkable heterogeneity exhibited by activated T cells. Collectively, these findings underscore progress in delineating the underlying pathways that control diversification in T cell responses but also reveal gaps in the knowledge, as well as the challenges that arise in the application of this knowledge to rationally elicit desired T cell responses through vaccination and immunotherapy. PMID:25396352

Cellular complexity captured in durable silica biocomposites

PubMed Central

Kaehr, Bryan; Townson, Jason L.; Kalinich, Robin M.; Awad, Yasmine H.; Swartzentruber, B. S.; Dunphy, Darren R.; Brinker, C. Jeffrey

2012-01-01

Tissue-derived cultured cells exhibit a remarkable range of morphological features in vitro, depending on phenotypic expression and environmental interactions. Translation of these cellular architectures into inorganic materials would provide routes to generate hierarchical nanomaterials with stabilized structures and functions. Here, we describe the fabrication of cell/silica composites (CSCs) and their conversion to silica replicas using mammalian cells as scaffolds to direct complex structure formation. Under mildly acidic solution conditions, silica deposition is restricted to the molecularly crowded cellular template. Inter- and intracellular heterogeneity from the nano- to macroscale is captured and dimensionally preserved in CSCs following drying and subjection to extreme temperatures allowing, for instance, size and shape preserving pyrolysis of cellular architectures to form conductive carbon replicas. The structural and behavioral malleability of the starting material (cultured cells) provides opportunities to develop robust and economical biocomposites with programmed structures and functions. PMID:23045634

Herpes folliculitis masquerading as cutaneous lymphoma.

PubMed

Bae-Harboe, Yoon-Soo C; Bhawan, Jag; Demierre, Marie-France; Goldberg, Lynne J

2013-08-01

Herpes virus infections presenting as folliculitis are uncommon. We describe a 48-year-old white man with a distant history of a childhood gastric lymphoma and renal cell carcinoma presenting with an itchy eruption. He was concerned about recurrence. A punch biopsy revealed interface dermatitis with a dense atypical superficial and deep perivascular and periadnexal lymphohistiocytic infiltrate with occasional eosinophils extending to the subcutis, with destruction of vessel walls. It was composed of predominantly CD3-positive lymphocytes with scattered CD56-positive cells and CD20-positive cells, concerning for lymphoma. A T-cell gene rearrangement study was negative. Deeper sections uncovered multinucleated giant keratinocytes in the follicular epithelium of 1 hair follicle, consistent with herpes folliculitis. Cutaneous herpes infections can exhibit several variable clinical and histopathological features. Knowledge of alternative presentations of herpes infections, histological clues to the presence of herpes infections, and careful clinicopathological correlation are necessary to differentiate herpes infections from cutaneous lymphomas and other inflammatory dermatoses.

Reassessing apoptosis in plants.

PubMed

Dickman, Martin; Williams, Brett; Li, Yurong; de Figueiredo, Paul; Wolpert, Thomas

2017-10-01

Cell death can be driven by a genetically programmed signalling pathway known as programmed cell death (PCD). In plants, PCD occurs during development as well as in response to environmental and biotic stimuli. Our understanding of PCD regulation in plants has advanced significantly over the past two decades; however, the molecular machinery responsible for driving the system remains elusive. Thus, whether conserved PCD regulatory mechanisms include plant apoptosis remains enigmatic. Animal apoptotic regulators, including Bcl-2 family members, have not been identified in plants but expression of such regulators can trigger or suppress plant PCD. Moreover, plants exhibit nearly all of the biochemical and morphological features of apoptosis. One difference between plant and animal PCD is the absence of phagocytosis in plants. Evidence is emerging that the vacuole may be key to removal of unwanted plant cells, and may carry out functions that are analogous to animal phagocytosis. Here, we provide context for the argument that apoptotic-like cell death occurs in plants.

Keratin 17 null mice exhibit age- and strain-dependent alopecia.

PubMed

McGowan, Kevin M; Tong, Xuemei; Colucci-Guyon, Emma; Langa, Francina; Babinet, Charles; Coulombe, Pierre A

2002-06-01

Onset of type I keratin 17 (K17) synthesis marks the adoption of an appendageal fate within embryonic ectoderm, and its expression persists in specific cell types within mature hair, glands, and nail. We report that K17 null mice develop severe alopecia during the first week postbirth, correlating with hair fragility, alterations in follicular histology, and apoptosis in matrix cells. These alterations are incompletely penetrant and normalize starting with the first postnatal cycle. Absence of a hair phenotype correlates with a genetic strain-dependent compensation by related keratins, including K16. These findings reveal a crucial role for K17 in the structural integrity of the first hair produced and the survival of hair-producing cells. Given that identical inherited mutations in this gene can cause either pachyonychia congenita or steatocystoma multiplex, the features of this mouse model suggest that this clinical heterogeneity arises from a cell type-specific, genetically determined compensation by related keratins.

IgG4-Related Disease of the Thyroid Gland Requiring Emergent Total Thyroidectomy: A Case Report.

PubMed

Zhao, Zitong; Lee, Yu Jin; Zheng, Shuwei; Khor, Li Yan; Lim, Kok Hing

2018-05-31

IgG4-related disease of the thyroid gland is a recently recognized subtype of thyroiditis, often with rapid progression requiring surgical treatment. It is considered as a spectrum of disease varying from early IgG4-related Hashimoto's thyroiditis (HT) pattern to late fibrosing HT or Riedel's thyroiditis patterns. Here, we report a 47-year-old Malay woman presenting with progressively painless neck swelling over 3 years and subclinical hypothyroidism. Computed tomography (CT) scan revealed diffuse thyroid enlargement (up to 13 cm) with retrosternal extension and without regional lymphadenopathy. Fine needle aspiration of the thyroid showed a limited number of follicular epithelial cell groups with widespread Hurthle cell change and scanty background colloid, but no evidence of lymphocytosis. The cytologic features fell into the category of 'atypia of undetermined significance'. Subsequently, the patient developed hypercapnic respiratory failure secondary to extrinsic upper airway compression by the thyroid mass and underwent emergent total thyroidectomy. Histology of the thyroid showed diffuse dense lymphoplasmacytic infiltrate and fibrosis. Follicular cells exhibited reactive nuclear features and some Hurthle cell change. IgG4+ plasma cells were over 40/high power field while overall IgG4/IgG ratio was above 50%. The overall features suggest the diagnosis of IgG4-related disease of the thyroid gland in the form of IgG4-related HT. Post-surgery, the patient was found to have markedly elevated serum IgG4 concentration but PET/CT did not show significant increased fludeoxyglucose uptake in other areas. Her recovery was complicated by a ventilator-associated pneumonia with empyema, limiting early use of corticosteroids for treatment of IgG4-related disease.

[Immunohistochemical study of perivascular epithelioid cell neoplasms].

PubMed

Xia, Qiu-Yuan; Rao, Qiu; Shen, Qin; Liu, Biao; Li, Li; Shi, Qun-Li; Shi, Shan-Shan; Yu, Bo; Zhang, Ru-Song; Ma, Heng-Hui; Lu, Zhen-Feng; Wang, Xuan; Tu, Pin; Zhou, Xiao-Jun

2013-06-01

To study the clinicopathologic features, immunophenotype and genetic changes of perivascular epithelioid cell neoplasms (PEComa). A total of 25 cases of PEComa located in various anatomic sites were selected for immunohistochemical staining (SP or EnVision method). TFE3 fluorescence in-situ hybridization was also performed to determine the TFE3 gene status. The age of patient ranged from 21 to 61 years (mean = 43 years). The male-to-female ratio was 1: 1.3. Histologically, 22 cases represented conventional angiomyolipomas, composed of a mixture of adipose tissue, spindle element, epithelioid smooth muscle cells and abnormal thick-walled blood vessels in various proportions. Three cases involving lung, soft tissue and broad ligament had subtle but distinctive morphologic features. Nested or sheet-like architecture with epithelioid or spindle cells was observed. Immunohistochemical study showed that HMB 45, melan A, smooth muscle actin and cathepsin K were expressed in 80% (20/25), 88% (22/25), 88% (22/25) and 100% (25/25) of PEComa, respectively. Within positive cases, the average proportion of positive tumor cells was 36%, 41%, 35% and 90% respectively for HMB 45, melan A, smooth muscle actin and cathepsin K. TFE3 was negative in all of the 22 renal and hepatic PEComa studied, while it was positive in the 3 cases of extra-hepatorenal PEComa. None of the 25 cases exhibited evidence of TFE3 gene fusion or amplification. Extra-hepatorenal PEComa have distinctive morphologic features and are associated with TFE3 overexpression. Cathepsin K immunostaining demonstrates high sensitivity and specificity in PEComa, better than other commonly employed immunomarkers. This marker is thus useful in diagnosis of PEComa and distinction with other neoplasms.

An adaptable neuromorphic model of orientation selectivity based on floating gate dynamics

PubMed Central

Gupta, Priti; Markan, C. M.

2014-01-01

The biggest challenge that the neuromorphic community faces today is to build systems that can be considered truly cognitive. Adaptation and self-organization are the two basic principles that underlie any cognitive function that the brain performs. If we can replicate this behavior in hardware, we move a step closer to our goal of having cognitive neuromorphic systems. Adaptive feature selectivity is a mechanism by which nature optimizes resources so as to have greater acuity for more abundant features. Developing neuromorphic feature maps can help design generic machines that can emulate this adaptive behavior. Most neuromorphic models that have attempted to build self-organizing systems, follow the approach of modeling abstract theoretical frameworks in hardware. While this is good from a modeling and analysis perspective, it may not lead to the most efficient hardware. On the other hand, exploiting hardware dynamics to build adaptive systems rather than forcing the hardware to behave like mathematical equations, seems to be a more robust methodology when it comes to developing actual hardware for real world applications. In this paper we use a novel time-staggered Winner Take All circuit, that exploits the adaptation dynamics of floating gate transistors, to model an adaptive cortical cell that demonstrates Orientation Selectivity, a well-known biological phenomenon observed in the visual cortex. The cell performs competitive learning, refining its weights in response to input patterns resembling different oriented bars, becoming selective to a particular oriented pattern. Different analysis performed on the cell such as orientation tuning, application of abnormal inputs, response to spatial frequency and periodic patterns reveal close similarity between our cell and its biological counterpart. Embedded in a RC grid, these cells interact diffusively exhibiting cluster formation, making way for adaptively building orientation selective maps in silicon. PMID:24765062

Characterization of Three Different Unusual S-Layer Proteins from Viridibacillus arvi JG-B58 That Exhibits Two Super-Imposed S-Layer Proteins

PubMed Central

Günther, Tobias J.; Raff, Johannes; Pollmann, Katrin

2016-01-01

Genomic analyses of Viridibacillus arvi JG-B58 that was previously isolated from heavy metal contaminated environment identified three different putative surface layer (S-layer) protein genes namely slp1, slp2, and slp3. All three genes are expressed during cultivation. At least two of the V. arvi JG-B58 S-layer proteins were visualized on the surface of living cells via atomic force microscopy (AFM). These S-layer proteins form a double layer with p4 symmetry. The S-layer proteins were isolated from the cells using two different methods. Purified S-layer proteins were recrystallized on SiO2 substrates in order to study the structure of the arrays and self-assembling properties. The primary structure of all examined S-layer proteins lack some features that are typical for Bacillus or Lysinibacillus S-layers. For example, they possess no SLH domains that are usually responsible for the anchoring of the proteins to the cell wall. Further, the pI values are relatively high ranging from 7.84 to 9.25 for the matured proteins. Such features are typical for S-layer proteins of Lactobacillus species although sequence comparisons indicate a close relationship to S-layer proteins of Lysinibacillus and Bacillus strains. In comparison to the numerous descriptions of S-layers, there are only a few studies reporting the concomitant existence of two different S-layer proteins on cell surfaces. Together with the genomic data, this is the first description of a novel type of S-layer proteins showing features of Lactobacillus as well as of Bacillus-type S-layer proteins and the first study of the cell envelope of Viridibacillus arvi. PMID:27285458

Surgical management and histologic and immunohistochemical features of a cataract and retrolental plaque secondary to persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous (PHTVL/PHPV) in a Bloodhound puppy.

PubMed

Gemensky-Metzler, Anne J; Wilkie, David A

2004-01-01

The objective of this study was to describe the clinical, histologic and immunohistochemical features, the surgical treatment, and outcome of a cataract secondary to persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous (PHTVL/PHPV) in a dog. A 4-month-old male Bloodhound dog presented for evaluation of a cataract. A complete ophthalmic examination and ocular ultrasonography were performed. A resorbing cataract with intralenticular hemorrhage, lens induced uveitis, and PHTVL/PHPV were diagnosed. Extracapsular cataract extraction using phacoemulsification was performed. A primary posterior capsulectomy was performed to remove a retrolental plaque with the posterior capsule; the excised plaque was submitted for histopathology and immunohistochemical staining. A 41-Diopter intraocular lens (IOL) was implanted. Functional vision was maintained postoperatively during the 21-month follow-up period. Histologically, the posterior capsule was coiled and exhibited duplication. The retrolental plaque was comprised of dense fibrous connective tissue, blood vessels, free red blood cells, hemosiderin-laden macrophages, a pocket of neural tissue and numerous perivascular mast cells. With immunohistochemical staining, the neural elements were determined to be glial cells compatible with astrocytes. Cataract secondary to PHTVL/PHPV can be successfully treated using phacoemulsification and planned posterior capsulectomy. Posterior lens capsule duplication, mast cells and astrocytic glial cells may be normal components of the fibrovascular retrolental plaque associated with PHTVL/PHPV.

CD38-NAD+Axis Regulates Immunotherapeutic Anti-Tumor T Cell Response.

PubMed

Chatterjee, Shilpak; Daenthanasanmak, Anusara; Chakraborty, Paramita; Wyatt, Megan W; Dhar, Payal; Selvam, Shanmugam Panneer; Fu, Jianing; Zhang, Jinyu; Nguyen, Hung; Kang, Inhong; Toth, Kyle; Al-Homrani, Mazen; Husain, Mahvash; Beeson, Gyda; Ball, Lauren; Helke, Kristi; Husain, Shahid; Garrett-Mayer, Elizabeth; Hardiman, Gary; Mehrotra, Meenal; Nishimura, Michael I; Beeson, Craig C; Bupp, Melanie Gubbels; Wu, Jennifer; Ogretmen, Besim; Paulos, Chrystal M; Rathmell, Jeffery; Yu, Xue-Zhong; Mehrotra, Shikhar

2018-01-09

Heightened effector function and prolonged persistence, the key attributes of Th1 and Th17 cells, respectively, are key features of potent anti-tumor T cells. Here, we established ex vivo culture conditions to generate hybrid Th1/17 cells, which persisted long-term in vivo while maintaining their effector function. Using transcriptomics and metabolic profiling approaches, we showed that the enhanced anti-tumor property of Th1/17 cells was dependent on the increased NAD + -dependent activity of the histone deacetylase Sirt1. Pharmacological or genetic inhibition of Sirt1 activity impaired the anti-tumor potential of Th1/17 cells. Importantly, T cells with reduced surface expression of the NADase CD38 exhibited intrinsically higher NAD + , enhanced oxidative phosphorylation, higher glutaminolysis, and altered mitochondrial dynamics that vastly improved tumor control. Lastly, blocking CD38 expression improved tumor control even when using Th0 anti-tumor T cells. Thus, strategies targeting the CD38-NAD + axis could increase the efficacy of anti-tumor adoptive T cell therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Bio-functionalized silk hydrogel microfluidic systems.

PubMed

Zhao, Siwei; Chen, Ying; Partlow, Benjamin P; Golding, Anne S; Tseng, Peter; Coburn, Jeannine; Applegate, Matthew B; Moreau, Jodie E; Omenetto, Fiorenzo G; Kaplan, David L

2016-07-01

Bio-functionalized microfluidic systems were developed based on a silk protein hydrogel elastomeric materials. A facile multilayer fabrication method using gelatin sacrificial molding and layer-by-layer assembly was implemented to construct interconnected, three dimensional (3D) microchannel networks in silk hydrogels at 100 μm minimum feature resolution. Mechanically activated valves were implemented to demonstrate pneumatic control of microflow. The silk hydrogel microfluidics exhibit controllable mechanical properties, long-term stability in various environmental conditions, tunable in vitro and in vivo degradability in addition to optical transparency, providing unique features for cell/tissue-related applications than conventional polydimethylsiloxane (PDMS) and existing hydrogel-based microfluidic options. As demonstrated in the work here, the all aqueous-based fabrication process at ambient conditions enabled the incorporation of active biological substances in the bulk phase of these new silk microfluidic systems during device fabrication, including enzymes and living cells, which are able to interact with the fluid flow in the microchannels. These silk hydrogel-based microfluidic systems offer new opportunities in engineering active diagnostic devices, tissues and organs that could be integrated in vivo, and for on-chip cell sensing systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Human cancer cells utilize mitotic DNA synthesis to resist replication stress at telomeres regardless of their telomere maintenance mechanism

PubMed Central

Özer, Özgün; Bhowmick, Rahul; Liu, Ying; Hickson, Ian D.

2018-01-01

Telomeres resemble common fragile sites (CFSs) in that they are difficult-to-replicate and exhibit fragility in mitosis in response to DNA replication stress. At CFSs, this fragility is associated with a delay in the completion of DNA replication until early mitosis, whereupon cells are proposed to switch to a RAD52-dependent form of break-induced replication. Here, we show that this mitotic DNA synthesis (MiDAS) is also a feature of human telomeres. Telomeric MiDAS is not restricted to those telomeres displaying overt fragility, and is a feature of a wide range of cell lines irrespective of whether their telomeres are maintained by telomerase or by the alternative lengthening of telomeres (ALT) mechanism. MiDAS at telomeres requires RAD52, and is mechanistically similar to CFS-associated MiDAS, with the notable exception that telomeric MiDAS does not require the MUS81-EME1 endonuclease. We propose a model whereby replication stress initiates a RAD52-dependent form of break-induced replication that bypasses a requirement for MUS81-EME1 to complete DNA synthesis in mitosis. PMID:29662610

A New Conditionally Immortalized Human Fetal Brain Pericyte Cell Line: Establishment and Functional Characterization as a Promising Tool for Human Brain Pericyte Studies.

PubMed

Umehara, Kenta; Sun, Yuchen; Hiura, Satoshi; Hamada, Koki; Itoh, Motoyuki; Kitamura, Keita; Oshima, Motohiko; Iwama, Atsushi; Saito, Kosuke; Anzai, Naohiko; Chiba, Kan; Akita, Hidetaka; Furihata, Tomomi

2018-07-01

While pericytes wrap around microvascular endothelial cells throughout the human body, their highest coverage rate is found in the brain. Brain pericytes actively contribute to various brain functions, including the development and stabilization of the blood-brain barrier (BBB), tissue regeneration, and brain inflammation. Accordingly, detailed characterization of the functional nature of brain pericytes is important for understanding the mechanistic basis of brain physiology and pathophysiology. Herein, we report on the development of a new human brain pericyte cell line, hereafter referred to as the human brain pericyte/conditionally immortalized clone 37 (HBPC/ci37). Developed via the cell conditionally immortalization method, these cells exhibited excellent proliferative ability at 33 °C. However, when cultured at 37 °C, HBPC/ci37 cells showed a differentiated phenotype that was marked by morphological alterations and increases in several pericyte-enriched marker mRNA levels, such as platelet-derived growth factor receptor β. It was also found that HBPC/ci37 cells possessed the facilitative ability of in vitro BBB formation and differentiation into a neuronal lineage. Furthermore, HBPC/ci37 cells exhibited the typical "reactive" features of brain pericytes in response to pro-inflammatory cytokines. To summarize, our results clearly demonstrate that HBPC/ci37 cells possess the ability to perform several key brain pericyte functions while also showing the capacity for extensive and continuous proliferation. Based on these findings, it can be expected that, as a unique human brain pericyte model, HBPC/ci37 cells have the potential to contribute to significant advances in the understanding of human brain pericyte physiology and pathophysiology.

Dendritic cells loaded with HeLa-derived exosomes simulate an antitumor immune response.

PubMed

Ren, Guoping; Wang, Yanhong; Yuan, Shexia; Wang, Baolian

2018-05-01

The aim of the present study was to investigate the effect of loading dendritic cells (DCs) with HeLa-derived exosomes on cytotoxic T-lymphocyte (CTL) responses, and the cytotoxic effects of CTL responses on the HeLa cell line. Ultrafiltration centrifugation combined with sucrose density gradient ultracentrifugation was applied to isolate exosomes (HeLa-exo) from the supernatant of HeLa cells. Morphological features of HeLa-exo were identified by transmission electron microscopy (TEM), and the expression of cluster of differentiation (CD)63 was detected by western blotting. Next, monocytes were isolated from peripheral blood and cultured with the removal of adherent cells to induce DC proliferation. DCs were then phenotypically characterized by flow cytometry. Finally, MTT assays were performed to analyze the effects of DCs loaded with HeLa-exo on T cell proliferation and cytotoxicity assays to evaluate the effect of CTL responses on HeLa cells. TEM revealed that HeLa-exo exhibit typical cup-shaped morphology with a diameter range of 30-100 nm. It was also identified that the CD63 surface antigen is expressed on HeLa-exo. Furthermore, monocyte-derived DCs were able to express CD1a, suggesting that DC induction was a success. DCs exhibited hair-like protrusions and other typical dendritic cell morphology. Furthermore, DCs loaded with HeLa-exo could enhance CTL proliferation and the cytotoxic activity of CTLs compared with DCs without HeLa-exo (P<0.05). In conclusion, DCs loaded with HeLa-exo may promote T cell proliferation and induce CTL responses to inhibit the growth of cervical cancer cells in vitro .

Malignant perivascular epithelioid cell neoplasm (PEComa) of the urinary bladder with TFE3 gene rearrangement: clinicopathologic, immunohistochemical, and molecular features.

PubMed

Williamson, Sean R; Bunde, Paula J; Montironi, Rodolfo; Lopez-Beltran, Antonio; Zhang, Shaobo; Wang, Mingsheng; Maclennan, Gregory T; Cheng, Liang

2013-10-01

Recently, a small subgroup of PEComas has been recognized to harbor rearrangements involving TFE3, a gene also involved in rearrangements in translocation-associated renal cell carcinomas and alveolar soft part sarcomas. The few TFE3 rearrangement-associated PEComas reported have exhibited distinctive pathologic characteristics contrasting to PEComas in general, including predominantly epithelioid nested or alveolar morphology and underexpression of muscle markers by immunohistochemistry. In this study, we report the clinicopathologic, immunohistochemical, and molecular features of a primary urinary bladder PEComa diagnosed by transurethral resection in a 55-year-old woman that clinically mimicked urothelial carcinoma. Light microscopy demonstrated mixed spindle cell and epithelioid morphology with the epithelioid component preferentially associated with blood vessels. Immunohistochemistry revealed positive staining for HMB45, tyrosinase, MiTF, cathepsin K, smooth muscle actin, and TFE3 protein. Fluorescence in situ hybridization for the TFE3 gene revealed a split signal pattern, indicating TFE3 rearrangement. X chromosome inactivation analysis demonstrated a clonal pattern despite the heterogenous appearance of the tumor. Unfortunately, despite surgical resection and sarcoma-directed therapy, the patient died of metastatic disease 12 months after diagnosis. This report adds to the known data regarding urinary bladder PEComas and PEComas with TFE3 rearrangement, indicating that both can pursue an aggressive course. Although the few reported TFE3-rearranged PEComas have predominantly lacked a spindle cell component and expression of smooth muscle actin and MiTF by immunohistochemistry, the findings in this study indicate that these features are sometimes present in TFE3-rearranged PEComas.

Stem/progenitor cell-like properties of desmoglein 3dim cells in primary and immortalized keratinocyte lines.

PubMed

Wan, Hong; Yuan, Ming; Simpson, Cathy; Allen, Kirsty; Gavins, Felicity N E; Ikram, Mohammed S; Basu, Subham; Baksh, Nuzhat; O'Toole, Edel A; Hart, Ian R

2007-05-01

We showed previously that primary keratinocytes selected for low desmoglein 3 (Dsg3) expression levels exhibited increased colony-forming efficiency and heightened proliferative potential relative to cells with higher Dsg3 expression levels, characteristics consistent with a more "stem/progenitor cell-like" phenotype. Here, we have confirmed that Dsg3(dim) cells derived from cultured primary human adult keratinocytes have comparability with alpha(6)(bri)/CD71(dim) stem cells in terms of colony-forming efficiency. Moreover, these Dsg3(dim) cells exhibit increased reconstituting ability in in vitro organotypic culture on de-epidermalized dermis (DED); they are small, actively cycling cells, and they express elevated levels of various p63 isoforms. In parallel, using the two immortalized keratinocyte cell lines HaCaT and NTERT, we obtained essentially similar though occasionally different findings. Thus, reduced colony-forming efficiency by Dsg3(bri) cells consistently was observed in both cell lines even though the cell cycle profile and levels of p63 isoforms in the bri and dim populations differed between these two cell lines. Dsg3(dim) cells from both immortalized lines produced thicker and better ordered hierarchical structural organization of reconstituted epidermis relative to Dsg3(bri) and sorted control cells. Dsg3(dim) HaCaT cells also show sebocyte-like differentiation in the basal compartment of skin reconstituted after a 4-week organotypic culture. No differences in percentages of side population cells (also a putative marker of stem cells) were detected between Dsg3(dim) and Dsg3(bri) populations. Taken together our data indicate that Dsg3(dim) populations from primary human adult keratinocytes and long-term established keratinocyte lines possess certain stem/progenitor cell-like properties, although the side population characteristic is not one of these features. Disclosure of potential conflicts of interest is found at the end of this article.

Chemokine-like factor-like MARVEL transmembrane domain-containing 3 expression is associated with a favorable prognosis in esophageal squamous cell carcinoma.

PubMed

Han, Tianci; Shu, Tianci; Dong, Siyuan; Li, Peiwen; Li, Weinan; Liu, Dali; Qi, Ruiqun; Zhang, Shuguang; Zhang, Lin

2017-05-01

Decreased expression of human chemokine-like factor-like MARVEL transmembrane domain-containing 3 (CMTM3) has been identified in a number of human tumors and tumor cell lines, including gastric and testicular cancer, and PC3, CAL27 and Tca-83 cell lines. However, the association between CMTM3 expression and the clinicopathological features and prognosis of esophageal squamous cell carcinoma (ESCC) patients remains unclear. The aim of the present study was to investigate the correlation between CMTM3 expression and clinicopathological parameters and prognosis in ESCC. CMTM3 mRNA and protein expression was analyzed in ESCC and paired non-tumor tissues by quantitative real-time polymerase chain reaction, western blotting and immunohistochemical analysis. The Kaplan-Meier method was used to plot survival curves and the Cox proportional hazards regression model was also used for univariate and multivariate survival analysis. The results revealed that CMTM3 mRNA and protein expression levels were lower in 82.5% (30/40) and 75% (30/40) of ESCC tissues, respectively, when compared with matched non-tumor tissues. Statistical analysis demonstrated that CMTM3 expression was significantly correlated with lymph node metastasis (P=0.002) and clinical stage (P<0.001) in ESCC tissues. Furthermore, the survival time of ESCC patients exhibiting low CMTM3 expression was significantly shorter than that of ESCC patients exhibiting high CMTM3 expression (P=0.01). In addition, Kaplan-Meier survival analysis revealed that the overall survival time of patients exhibiting low CMTM3 expression was significantly decreased compared with patients exhibiting high CMTM3 expression (P=0.010). Cox multivariate analysis indicated that CMTM3 protein expression was an independent prognostic predictor for ESCC after resection. This study indicated that CMTM3 expression is significantly decreased in ESCC tissues and CMTM3 protein expression in resected tumors may present an effective prognostic biomarker.

Sonoporation as a cellular stress: induction of morphological repression and developmental delays.

PubMed

Chen, Xian; Wan, Jennifer M F; Yu, Alfred C H

2013-06-01

For sonoporation to be established as a drug/gene delivery paradigm, it is essential to account for the biological impact of this membrane permeation strategy on living cells. Here we provide new insight into the cellular impact of sonoporation by demonstrating in vitro that this way of permeating the plasma membrane may inadvertently induce repressive cellular features even while enhancing exogenous molecule uptake. Both suspension-type (HL-60) and monolayer (ZR-75-30) cells were considered in this investigation, and they were routinely exposed to 1-MHz pulsed ultrasound (pulse length, 100 cycles; pulse repetition frequency, 1 kHz; exposure period, 60 s) with calibrated field profile (spatial-averaged peak negative pressure, 0.45 MPa) and in the presence of microbubbles (cell:bubble ratio, 10:1). The post-exposure morphology of sonoporated cells (identified as those with calcein internalization) was examined using confocal microscopy, and their cell cycle progression kinetics were analyzed using flow cytometry. Results show that for both cell types investigated, sonoporated cells exhibited membrane shrinkage and intra-cellular lipid accumulation over a 2-h period. Also, as compared with normal cells, the deoxyribonucleic acid synthesis duration of sonoporated cells was significantly lengthened, indicative of a delay in cell cycle progression. These features are known to be characteristics of a cellular stress response, suggesting that sonoporation indeed constitutes as a stress to living cells. This issue may need to be addressed in optimizing sonoporation for drug/gene delivery purposes. On the other hand, it raises opportunities for developing other therapeutic applications via sonoporation. Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Characterization of reproductive, metabolic, and endocrine features of polycystic ovary syndrome in female hyperandrogenic mouse models.

PubMed

Caldwell, A S L; Middleton, L J; Jimenez, M; Desai, R; McMahon, A C; Allan, C M; Handelsman, D J; Walters, K A

2014-08-01

Polycystic ovary syndrome (PCOS) affects 5-10% of women of reproductive age, causing a range of reproductive, metabolic and endocrine defects including anovulation, infertility, hyperandrogenism, obesity, hyperinsulinism, and an increased risk of type 2 diabetes and cardiovascular disease. Hyperandrogenism is the most consistent feature of PCOS, but its etiology remains unknown, and ethical and logistic constraints limit definitive experimentation in humans to determine mechanisms involved. In this study, we provide the first comprehensive characterization of reproductive, endocrine, and metabolic PCOS traits in 4 distinct murine models of hyperandrogenism, comprising prenatal dihydrotestosterone (DHT, potent nonaromatizable androgen) treatment during days 16-18 of gestation, or long-term treatment (90 days from 21 days of age) with DHT, dehydroepiandrosterone (DHEA), or letrozole (aromatase inhibitor). Prenatal DHT-treated mature mice exhibited irregular estrous cycles, oligo-ovulation, reduced preantral follicle health, hepatic steatosis, and adipocyte hypertrophy, but lacked overall changes in body-fat composition. Long-term DHT treatment induced polycystic ovaries displaying unhealthy antral follicles (degenerate oocyte and/or > 10% pyknotic granulosa cells), as well as anovulation and acyclicity in mature (16-week-old) females. Long-term DHT also increased body and fat pad weights and induced adipocyte hypertrophy and hypercholesterolemia. Long-term letrozole-treated mice exhibited absent or irregular cycles, oligo-ovulation, polycystic ovaries containing hemorrhagic cysts atypical of PCOS, and displayed no metabolic features of PCOS. Long-term dehydroepiandrosterone treatment produced no PCOS features in mature mice. Our findings reveal that long-term DHT treatment replicated a breadth of ovarian, endocrine, and metabolic features of human PCOS and provides the best mouse model for experimental studies of PCOS pathogenesis.

Anaplasia in pilocytic astrocytoma predicts aggressive behavior.

PubMed

Rodriguez, Fausto J; Scheithauer, Bernd W; Burger, Peter C; Jenkins, Sarah; Giannini, Caterina

2010-02-01

The clinical significance of anaplastic features, a rare event in pilocytic astrocytoma (PA), is not fully established. We reviewed 34 PA with anaplastic features (Male = 21, Female = 13; median age 35 y, 5 to 75) among approximately 2200 PA cases (1.7%). Tumors were included which demonstrated brisk mitotic activity [at least 4 mitoses/10 high power fields (400 x )], in addition to hypercellularity and moderate-to-severe cytologic atypia, with or without necrosis. The tumors either had a PA precursor, coexistent (n = 14) (41%) or documented by previous biopsy (n = 10) (29%), or exhibited typical pilocytic features in an otherwise anaplastic astrocytoma (n = 10) (29%). Clinical features of neurofibromatosis type-1 were present in 24% and a history of radiation for PA precursor in 12%. Histologically, the anaplastic component was classified as pilocytic like (41%), small cell (32%), epithelioid (15%), or fibrillary (12%). Median MIB1 labeling index was 24.7% in the anaplastic component and 2.6% in the precursor, although overlapping values were present. Strong p53 staining (3+) was limited to areas with anaplasia (19%), with overlapping values for 1 and 2+ in areas without anaplasia. Median overall and progression-free survivals after diagnosis for the entire study group were 24 and 14 months, respectively. Overall and progression-free survivals were shorter in the setting of prior radiation for a PA precursor (P = 0.007, 0.028), increasing mitotic activity (P = 0.03, 0.02), and presence of necrosis (P = 0.02, 0.02), after adjusting for age and site. The biologic behavior of PAs with high-mitotic rates and those with necrosis paralleled that of St Anne-Mayo grades 2 and 3 diffuse astrocytomas, respectively. In summary, PA with anaplastic features exhibits a spectrum of morphologies and is associated with decreased survival when compared with typical PA.

iPSC-derived cancer stem cells provide a model of tumor vasculature.

PubMed

Prieto-Vila, Marta; Yan, Ting; Calle, Anna Sanchez; Nair, Neha; Hurley, Laura; Kasai, Tomonari; Kakuta, Hiroki; Masuda, Junko; Murakami, Hiroshi; Mizutani, Akifumi; Seno, Masaharu

2016-01-01

To grow beyond a size of approximately 1-2 mm 3 , tumor cells activate many processes to develop blood vasculature. Growing evidences indicate that the formation of the tumor vascular network is very complex, and is not restricted to angiogenesis. Cancer cell-derived tumor vasculatures have been recently described. Among them, endothelial differentiation of tumor cells have been directly related to cancer stem cells, which are cells within a tumor that possess the capacity to self-renew, and to exhibit multipotential heterogeneous lineages of cancer cells. Vasculogenic mimicry has been described to be formed by cancer cells expressing stemness markers. Thus, cancer stem cells have been proposed to contribute to vasculogenic mimicry, though its relation is yet to be clarified. Here, we analyzed the tumor vasculature by using a model of mouse cancer stem cells, miPS-LLCcm cells, which we have previously established from mouse induced pluripotent stem cells and we introduced the DsRed gene in miPS-LLCcm to trace them in vivo . Various features of vasculature were evaluated in ovo , in vitro , and in vivo . The tumors formed in allograft nude mice exhibited angiogenesis in chick chorioallantoic membrane assay. In those tumors, along with penetrated host endothelial vessels, we detected endothelial differentiation from cancer stem cells and formation of vasculogenic mimicry. The angiogenic factors such as VEGF-A and FGF2 were expressed predominantly in the cancer stem cells subpopulation of miPS-LLCcm cells. Our results suggested that cancer stem cells play key roles in not only the recruitment of host endothelial vessels into tumor, but also in maturation of endothelial linage of cancer stem cell's progenies. Furthermore, the undifferentiated subpopulation of the miPS-LLCcm participates directly in the vasculogenic mimicry formation. Collectively, we show that miPS-LLCcm cells have advantages to further study tumor vasculature and to develop novel targeting strategies in the future.

Potentially malignant disorders revisited-The lichenoid lesion/proliferative verrucous leukoplakia conundrum.

PubMed

Thomson, Peter J; Goodson, Michaela L; Smith, Daniel R

2018-04-16

Clinically identifiable potentially malignant disorders (PMD) precede oral squamous cell carcinoma development. Oral lichenoid lesions (OLL) and proliferative verrucous leukoplakia (PVL) are specific precursor lesions believed to exhibit both treatment resistance and a high risk of malignant transformation (MT). A retrospective review of 590 PMD patients treated in Northern England by CO 2 laser surgery between 1996 and 2014 was carried out. Lesions exhibiting lichenoid or proliferative verrucous features were identified from the patient database and their clinicopathological features and outcome post-treatment determined at the study census date of 31 December 2014. One hundred and 98 patients were identified as follows: 118 OLL and 80 PVL, most frequently leukoplakia at ventrolateral tongue and floor of mouth sites, equally distributed between males and females. Most exhibited dysplasia on incision biopsy (72% OLL; 85% PVL) and were treated by laser excision rather than ablation (88.1% OLL; 86.25% PVL). OLL were more common in younger patients (OLL 57.1 year; PVL 62.25 years; P = .008) and more likely than PVL to present as erythroleukoplakia (OLL 15.3%; PVL 2.5%; P = .003). Whilst no significant difference was seen between OLL and PVL achieving disease-free status (69.5% and 65%, respectively; P = .55), this was less than the overall PMD cohort (74.2%). MT was identified in 2 OLL (1.7%) and 2 PVL (2.5%) during follow-up. One-third of PMD cases showed features of OLL or PVL, probably representing a disease presentation continuum. Post-treatment disease-free status was less common in OLL and PVL, although MT was infrequent. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mutation of EpCAM leads to intestinal barrier and ion transport dysfunction.

PubMed

Kozan, Philip A; McGeough, Matthew D; Peña, Carla A; Mueller, James L; Barrett, Kim E; Marchelletta, Ronald R; Sivagnanam, Mamata

2015-05-01

Congenital tufting enteropathy (CTE) is a devastating diarrheal disease seen in infancy that is typically associated with villous changes and the appearance of epithelial tufts. We previously found mutations in epithelial cell adhesion molecule (EpCAM) to be causative in CTE. We developed a knock-down cell model of CTE through transfection of an EpCAM shRNA construct into T84 colonic epithelial cells to elucidate the in vitro role of EpCAM in barrier function and ion transport. Cells with EpCAM deficiency exhibited decreased electrical resistance, increased permeability, and decreased ion transport. Based on mutations in CTE patients, an in vivo mouse model was developed, with tamoxifen-inducible deletion of exon 4 in Epcam resulting in mutant protein with decreased expression. Tamoxifen treatment of Epcam (Δ4/Δ4) mice resulted in pathological features of villous atrophy and epithelial tufts, similar to those in human CTE patients, within 4 days post induction. Epcam (Δ4/Δ4) mice also showed decreased expression of tight junctional proteins, increased permeability, and decreased ion transport in the intestines. Taken together, these findings reveal mechanisms that may underlie disease in CTE. Knock-down EpCAM cell model of congenital tufting enteropathy was developed. In vivo inducible mouse model was developed resulting in mutant EpCAM protein. Cells with EpCAM deficiency demonstrated barrier and ion transport dysfunction. Tamoxifen-treated Epcam (Δ4/Δ4) mice demonstrated pathological features. Epcam (Δ4/Δ4) mice showed improper barrier function and ion transport.

Association between intracranial plasmacytoma and multiple myeloma: clinicopathological outcome study.

PubMed

Schwartz, T H; Rhiew, R; Isaacson, S R; Orazi, A; Bruce, J N

2001-11-01

Intracranial plasmacytomas are rare lesions that can arise from the calvarium, dura, or cranial base and exhibit a benign course unless associated with myeloma. Attention has recently been focused on the role of the cell adhesion molecules CD56 and CD31 in the pathogenesis of myeloma. No such information is available for intracranial plasmacytomas and myeloma-associated lesions. We investigated the relationship between CD56 and CD31 expression, intracranial location, and progression to myeloma for a series of nine intracranial plasmacytomas (three dural, one calvarial, and five cranial base lesions). These parameters were also correlated with proliferation indices, as assessed by MIB-1 immunostaining of the histological sections. A single pathologist (AO) performed immunohistochemical analyses and reviewed all slides. Intracranial plasmacytomas presented more commonly in female patients (89%). The three dural lesions were CD56- and CD31-negative and exhibited MIB-1 staining of less than 10%; no patient developed myeloma or recurrence. Of the five cranial base lesions, three were CD56-positive, none was CD31-positive, and two exhibited MIB-1 labeling of more than 45%, with plasmablastic morphological features. Compared with other intracranial plasmacytomas, five of five patients with cranial base lesions developed bone marrow biopsy-proven myeloma (P < 0.05) within 8 months. The calvarial lesion was CD56- and CD31-positive, and the patient developed myeloma soon after diagnosis. Both of the two highly proliferative plasmablastic lesions recurred, one after gross total resection without radiotherapy and the other after a biopsy and 2000-cGy radiotherapy. Among intracranial plasmacytomas, cranial base location was the strongest predictor of the development of multiple myeloma. Expression of the cell adhesion molecules CD31 and CD56 was not predictive of outcome. Extramedullary dural-based lesions were CD56-negative and were not associated with myeloma. A high proliferation index and plasmablastic morphological features were predictive of a short time to recurrence and aggressive behavior. We recommend 4050- to 5040-cGy fractionated radiotherapy for all intracranial plasma cell neoplasms and gross total resection for non-cranial base lesions.

Label-free silicon nanodots featured ratiometric fluorescent aptasensor for lysosomal imaging and pH measurement.

PubMed

Zhang, Yanan; Guo, Shan; Cheng, Shibo; Ji, Xinghu; He, Zhike

2017-08-15

The homeostasis of lysosomal pH is crucial in cell physiology. Developing small fluorescent nanosensors for lysosome imaging and ratiometric measurement of pH is highly demanded yet challenging. Herein, a pH-sensitive fluorescein tagged aptamer AS1411 has been utilized to covalently modify the label-free fluorescent silicon nanodots via a crosslinker for construction of a ratiometric pH biosensor. The established aptasensor exhibits the advantages of ultrasmall size, hypotoxicity, excellent pH reversibility and good photostability, which favors its application in an intracellular environment. Using human breast MCF-7 cancer cells and MCF-10A normal cells as the model, this aptasensor shows cell specificity for cancer cells and displays a wide pH response range of 4.5-8.0 in living cells. The results demonstrate that the pH of MCF-7 cells is 5.1, which is the expected value for acidic organelles. Lysosome imaging and accurate measurement of pH in MCF-7 cells have been successfully conducted based on this nanosensor via fluorescent microscopy and flow cytometry. Copyright © 2017 Elsevier B.V. All rights reserved.

Antitumor potential of crown ethers: structure-activity relationships, cell cycle disturbances, and cell death studies of a series of ionophores.

PubMed

Marjanović, Marko; Kralj, Marijeta; Supek, Fran; Frkanec, Leo; Piantanida, Ivo; Smuc, Tomislav; Tusek-Bozić, Ljerka

2007-03-08

The present paper demonstrates the antiproliferative ability and structure-activity relationships (SAR) of 14 crown and aza-crown ether analogues on five tumor-cell types. The most active compounds were di-tert-butyldicyclohexano-18-crown-6 (3), which exhibited cytotoxicity in the submicromolar range, and di-tert-butyldibenzo-18-crown-6 (5) (IC50 values of approximately 2 microM). Also, 3 and 5 induced marked influence on the cell cycle phase distribution--strong G1 arrest, followed by the induction of apoptosis. A computational SAR modeling effort offers insight into possible mechanisms of crown ether biological activity, presumably involving penetration into cell membranes, and points out structural features of molecules important for this activity. The results reveal that crown ethers possess marked tumor-cell growth inhibitory activity, the extent of which depends on the characteristics of the hydrophilic macrocylic cavity and the surrounding hydrophobic ring. Our work supports the hypothesis that crown ether compounds inhibit tumor-cell growth by disrupting potassium ion homeostasis, which in turn leads to cell cycle perturbations and apoptosis.

Prion Replication Elicits Cytopathic Changes in Differentiated Neurosphere Cultures

PubMed Central

Iwamaru, Yoshifumi; Takenouchi, Takato; Imamura, Morikazu; Shimizu, Yoshihisa; Miyazawa, Kohtaro; Mohri, Shirou; Yokoyama, Takashi

2013-01-01

The molecular mechanisms of prion-induced cytotoxicity remain largely obscure. Currently, only a few cell culture models have exhibited the cytopathic changes associated with prion infection. In this study, we introduced a cell culture model based on differentiated neurosphere cultures isolated from the brains of neonatal prion protein (PrP)-null mice and transgenic mice expressing murine PrP (dNP0 and dNP20 cultures). Upon exposure to mouse Chandler prions, dNP20 cultures supported the de novo formation of abnormal PrP and the resulting infectivity, as assessed by bioassays. Furthermore, this culture was susceptible to various prion strains, including mouse-adapted scrapie, bovine spongiform encephalopathy, and Gerstmann-Sträussler-Scheinker syndrome prions. Importantly, a subset of the cells in the infected culture that was mainly composed of astrocyte lineage cells consistently displayed late-occurring, progressive signs of cytotoxicity as evidenced by morphological alterations, decreased cell viability, and increased lactate dehydrogenase release. These signs of cytotoxicity were not observed in infected dNP0 cultures, suggesting the requirement of endogenous PrP expression for prion-induced cytotoxicity. Degenerated cells positive for glial fibrillary acidic protein accumulated abnormal PrP and exhibited features of apoptotic death as assessed by active caspase-3 and terminal deoxynucleotidyltransferase nick-end staining. Furthermore, caspase inhibition provided partial protection from prion-mediated cell death. These results suggest that differentiated neurosphere cultures can provide an in vitro bioassay for mouse prions and permit the study of the molecular basis for prion-induced cytotoxicity at the cellular level. PMID:23740992

Segregated Excitatory–Inhibitory Recurrent Subnetworks in Layer 5 of the Rat Frontal Cortex

PubMed Central

Morishima, Mieko; Kobayashi, Kenta; Kato, Shigeki; Kobayashi, Kazuto; Kawaguchi, Yasuo

2017-01-01

Abstract A prominent feature of neocortical pyramidal cells (PCs) is their numerous projections to diverse brain areas. In layer 5 (L5) of the rat frontal cortex, there are 2 major subtypes of PCs that differ in their long-range axonal projections, corticopontine (CPn) cells and crossed corticostriatal (CCS) cells. The outputs of these L5 PCs can be regulated by feedback inhibition from neighboring cortical GABAergic cells. Two major subtypes of GABAergic cells are parvalbumin (PV)-positive and somatostatin (SOM)-positive cells. PV cells have a fast-spiking (FS) firing pattern, while SOM cells have a low threshold spike (LTS) and regular spiking. In this study, we found that the 2 PC subtypes in L5 selectively make recurrent connections with LTS cells. The connection patterns correlated with the morphological and physiological diversity of LTS cells. LTS cells with high input resistance (Ri) exhibited more compact dendrites and more rebound spikes than LTS cells with low Ri, which had vertically elongated dendrites. LTS subgroups differently inhibited the PC subtypes, although FS cells made nonselective connections with both projection subtypes. These results demonstrate a novel recurrent network of inhibitory and projection-specific excitatory neurons within the neocortex. PMID:29045559

Mucinous breast carcinoma with myoepithelial-like spindle cells.

PubMed

Miyake, Yasuyuki; Hirokawa, Mitsuyoshi; Norimatsu, Yoshiaki; Kanahara, Takuo; Monobe, Yasumasa; Ohno, Setsuyo; Miyamoto, Tomoyuki; Yakushiji, Hiromasa; Sakaguchi, Takuya; Aratake, Yatsuki; Ohno, Eiji

2009-06-01

Appearance of spindle cells has been believed as a benign index of breast cytology. But, we have frequently observed the spindle cells in smears from mucinous carcinoma of the breast. Here, we characterized the biochemical nature of the spindle cells, so as to clarify their identity in cytology. Nineteen cases of breast mucinous carcinoma were used for cytological examination. The spindle cells were located at edges of tumor cell nests and in the backgrounds of cytological specimens. Immunohistological examination revealed that the spindle cells exhibited both immunoreactivity against carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA). Immunoreactivity against vimentin, cytokeratin, or alpha-smooth muscle actin was, however, not observed. The mode of distribution of biochemical markers suggests that the positive cells for anti-CEA antibody and anti-EMA antibody are tumor cells compressed by mucin, while the vimentin-positive cells are fibroblasts. We assert that the presence of spindle cells can be a characteristic feature of mucinous carcinoma of the breast. Discrimination of the spindle cells in mucinous carcinoma from myoepithelial cells and naked bipolar nuclei in benign lesions was established here. It should facilitate precise diagnosis of breast cancer. (c) 2009 Wiley-Liss, Inc.

iPSC-derived cancer stem cells provide a model of tumor vasculature

PubMed Central

Prieto-Vila, Marta; Yan, Ting; Calle, Anna Sanchez; Nair, Neha; Hurley, Laura; Kasai, Tomonari; Kakuta, Hiroki; Masuda, Junko; Murakami, Hiroshi; Mizutani, Akifumi; Seno, Masaharu

2016-01-01

To grow beyond a size of approximately 1-2 mm3, tumor cells activate many processes to develop blood vasculature. Growing evidences indicate that the formation of the tumor vascular network is very complex, and is not restricted to angiogenesis. Cancer cell-derived tumor vasculatures have been recently described. Among them, endothelial differentiation of tumor cells have been directly related to cancer stem cells, which are cells within a tumor that possess the capacity to self-renew, and to exhibit multipotential heterogeneous lineages of cancer cells. Vasculogenic mimicry has been described to be formed by cancer cells expressing stemness markers. Thus, cancer stem cells have been proposed to contribute to vasculogenic mimicry, though its relation is yet to be clarified. Here, we analyzed the tumor vasculature by using a model of mouse cancer stem cells, miPS-LLCcm cells, which we have previously established from mouse induced pluripotent stem cells and we introduced the DsRed gene in miPS-LLCcm to trace them in vivo. Various features of vasculature were evaluated in ovo, in vitro, and in vivo. The tumors formed in allograft nude mice exhibited angiogenesis in chick chorioallantoic membrane assay. In those tumors, along with penetrated host endothelial vessels, we detected endothelial differentiation from cancer stem cells and formation of vasculogenic mimicry. The angiogenic factors such as VEGF-A and FGF2 were expressed predominantly in the cancer stem cells subpopulation of miPS-LLCcm cells. Our results suggested that cancer stem cells play key roles in not only the recruitment of host endothelial vessels into tumor, but also in maturation of endothelial linage of cancer stem cell’s progenies. Furthermore, the undifferentiated subpopulation of the miPS-LLCcm participates directly in the vasculogenic mimicry formation. Collectively, we show that miPS-LLCcm cells have advantages to further study tumor vasculature and to develop novel targeting strategies in the future. PMID:27725898

Establishment and characterization of novel epithelial-like cell lines derived from human periodontal ligament tissue in vitro.

PubMed

Tansriratanawong, Kallapat; Ishikawa, Hiroshi; Toyomura, Junko; Sato, Soh

2017-10-01

In this study, novel human-derived epithelial-like cells (hEPLCs) lines were established from periodontal ligament (PDL) tissues, which were composed of a variety of cell types and exhibited complex cellular activities. To elucidate the putative features distinguishing these from epithelial rest of Malassez (ERM), we characterized hEPLCs based on cell lineage markers and tight junction protein expression. The aim of this study was, therefore, to establish and characterize hEPLCs lines from PDL tissues. The hEPLCs were isolated from PDL of third molar teeth. Cellular morphology and cell organelles were observed thoroughly. The characteristics of epithelial-endothelial-mesenchymal-like cells were compared in several markers by gene expression and immunofluorescence, to ERM and human umbilical-vein endothelial cells (HUVECs). The resistance between cellular junctions was assessed by transepithelial electron resistance, and inflammatory cytokines were detected by ELISA after infecting hEPLCs with periodontopathic bacteria. The hEPLCs developed into small epithelial-like cells in pavement appearance similar to ERM. However, gene expression patterns and immunofluorescence results were different from ERM and HUVECs, especially in tight junction markers (Claudin, ZO-1, and Occludins), and endothelial markers (vWF, CD34). The transepithelial electron resistance indicated higher resistance in hEPLCs, as compared to ERM. Periodontopathic bacteria were phagocytosed with upregulation of inflammatory cytokine secretion within 24 h. In conclusion, hEPLCs that were derived using the single cell isolation method formed tight multilayers colonies, as well as strongly expressed tight junction markers in gene expression and immunofluorescence. Novel hEPLCs lines exhibited differently from ERM, which might provide some specific functions such as metabolic exchange and defense mechanism against bacterial invasion in periodontal tissue.

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

Yasuda, H.; Chong, C.; Charalampidis, E. G.

Here, we investigate the nonlinear wave dynamics of origami-based metamaterials composed of Tachi-Miura polyhedron (TMP) unit cells. These cells exhibit strain softening behavior under compression, which can be tuned by modifying their geometrical configurations or initial folded conditions. We assemble these TMP cells into a cluster of origami-based metamaterials, and we theoretically model and numerically analyze their wave transmission mechanism under external impact. Numerical simulations show that origami-based metamaterials can provide a prototypical platform for the formation of nonlinear coherent structures in the form of rarefaction waves, which feature a tensile wavefront upon the application of compression to the system.more » We also demonstrate the existence of numerically exact traveling rarefaction waves in an effective lumped-mass model. Origami-based metamaterials can be highly useful for mitigating shock waves, potentially enabling a wide variety of engineering applications.« less

Formation of rarefaction waves in origami-based metamaterials

NASA Astrophysics Data System (ADS)

Yasuda, H.; Chong, C.; Charalampidis, E. G.; Kevrekidis, P. G.; Yang, J.

2016-04-01

We investigate the nonlinear wave dynamics of origami-based metamaterials composed of Tachi-Miura polyhedron (TMP) unit cells. These cells exhibit strain softening behavior under compression, which can be tuned by modifying their geometrical configurations or initial folded conditions. We assemble these TMP cells into a cluster of origami-based metamaterials, and we theoretically model and numerically analyze their wave transmission mechanism under external impact. Numerical simulations show that origami-based metamaterials can provide a prototypical platform for the formation of nonlinear coherent structures in the form of rarefaction waves, which feature a tensile wavefront upon the application of compression to the system. We also demonstrate the existence of numerically exact traveling rarefaction waves in an effective lumped-mass model. Origami-based metamaterials can be highly useful for mitigating shock waves, potentially enabling a wide variety of engineering applications.

Flow and diffusion in channel-guided cell migration.

PubMed

Marel, Anna-Kristina; Zorn, Matthias; Klingner, Christoph; Wedlich-Söldner, Roland; Frey, Erwin; Rädler, Joachim O

2014-09-02

Collective migration of mechanically coupled cell layers is a notable feature of wound healing, embryonic development, and cancer progression. In confluent epithelial sheets, the dynamics have been found to be highly heterogeneous, exhibiting spontaneous formation of swirls, long-range correlations, and glass-like dynamic arrest as a function of cell density. In contrast, the flow-like properties of one-sided cell-sheet expansion in confining geometries are not well understood. Here, we studied the short- and long-term flow of Madin-Darby canine kidney (MDCK) cells as they moved through microchannels. Using single-cell tracking and particle image velocimetry (PIV), we found that a defined averaged stationary cell current emerged that exhibited a velocity gradient in the direction of migration and a plug-flow-like profile across the advancing sheet. The observed flow velocity can be decomposed into a constant term of directed cell migration and a diffusion-like contribution that increases with density gradient. The diffusive component is consistent with the cell-density profile and front propagation speed predicted by the Fisher-Kolmogorov equation. To connect diffusion-mediated transport to underlying cellular motility, we studied single-cell trajectories and occurrence of vorticity. We discovered that the directed large-scale cell flow altered fluctuations in cellular motion at short length scales: vorticity maps showed a reduced frequency of swirl formation in channel flow compared with resting sheets of equal cell density. Furthermore, under flow, single-cell trajectories showed persistent long-range, random-walk behavior superimposed on drift, whereas cells in resting tissue did not show significant displacements with respect to neighboring cells. Our work thus suggests that active cell migration manifests itself in an underlying, spatially uniform drift as well as in randomized bursts of short-range correlated motion that lead to a diffusion-mediated transport. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Comprehensive genomic profiling reveals inactivating SMARCA4 mutations and low tumor mutational burden in small cell carcinoma of the ovary, hypercalcemic-type.

PubMed

Lin, Douglas I; Chudnovsky, Yakov; Duggan, Bridget; Zajchowski, Deborah; Greenbowe, Joel; Ross, Jeffrey S; Gay, Laurie M; Ali, Siraj M; Elvin, Julia A

2017-12-01

Small cell carcinoma of the ovary, hypercalcemic-type (SCCOHT) is a rare, extremely aggressive neoplasm that usually occurs in young women and is characterized by deleterious germline or somatic SMARCA4 mutations. We performed comprehensive genomic profiling (CGP) to potentially identify additional clinically and pathophysiologically relevant genomic alterations in SCCOHT. CGP assessment of all classes of coding alterations in up to 406 genes commonly altered in cancer and intronic regions for up to 31 genes commonly rearranged in cancer was performed on 18 SCCOHT cases (16 exhibiting classic morphology and 2 cases exhibiting exclusive a large cell variant morphology). In addition, a retrospective database search for clinically advanced ovarian tumors with genomic profiles similar to SCCOHT yielded 3 additional cases originally diagnosed as non-SCCOHT. CGP revealed inactivating SMARCA4 alterations and low tumor mutational burden (TMB) (<6mutations/Mb) in 94% (15/16) of SCCOHT with classic morphology. In contrast, both (2/2) cases exhibiting only large cell variant morphology were hypermutated (TMB scores of 90 and 360mut/Mb) and were wildtype for SMARCA4. In our retrospective search, an index ovarian cancer patient harboring inactivating SMARCA4 alterations, initially diagnosed as endometrioid carcinoma, was re-classified as SCCOHT and responded to an SCCOHT chemotherapy regimen. The vast majority of SCCOHT demonstrate genomic SMARCA4 loss with only rare co-occurring alterations. Our data support a role for CGP in the diagnosis and management of SCCOHT and of other lesions with overlapping histological and clinical features, since identifying the former by genomic profile suggests benefit from an appropriate regimen and treatment decisions, as illustrated by an index patient. Copyright © 2017 Elsevier Inc. All rights reserved.

In vitro activity of the new water-dispersible Fe3O4@usnic acid nanostructure against planktonic and sessile bacterial cells

NASA Astrophysics Data System (ADS)

Grumezescu, Alexandru Mihai; Cotar, Ani Ioana; Andronescu, Ecaterina; Ficai, Anton; Ghitulica, Cristina Daniela; Grumezescu, Valentina; Vasile, Bogdan Stefan; Chifiriuc, Mariana Carmen

2013-07-01

A new water-dispersible nanostructure based on magnetite (Fe3O4) and usnic acid (UA) was prepared in a well-shaped spherical form by a precipitation method. Nanoparticles were well individualized and homogeneous in size. The presence of Fe3O4@UA was confirmed by transmission electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffraction. The UA was entrapped in the magnetic nanoparticles during preparation and the amount of entrapped UA was estimated by thermogravimetric analysis. Fabricated nanostructures were tested on planktonic cells growth (minimal inhibitory concentration assay) and biofilm development on Gram-positive Staphylococcus aureus ( S. aureus), Enterococcus faecalis ( E. faecalis) and Gram-negative Escherichia coli ( E. coli), Pseudomonas aeruginosa (P. aeruginosa) reference strains. Concerning the influence of Fe3O4@UA on the planktonic bacterial cells, the functionalized magnetic nanoparticles exhibited a significantly improved antimicrobial activity against E. faecalis and E. coli, as compared with the Fe3O4 control. The UA incorporated into the magnetic nanoparticles exhibited a very significant inhibitory effect on the biofilm formed by the S. aureus and E. faecalis, on a wide range of concentrations, while in case of the Gram-negative microbial strains, the UA-loaded nanoparticles inhibited the E. coli biofilm development, only at high concentrations, while for P. aeruginosa biofilms, no inhibitory effect was observed. The obtained results demonstrate that the new water-dispersible Fe3O4@UA nanosystem, combining the advantages of the intrinsic antimicrobial features of the UA with the higher surface to volume ratio provided by the magnetic nanocarrier dispersible in water, exhibits efficient antimicrobial activity against planktonic and adherent cells, especially on Gram-positive strains.

High-dose interleukin 2 in patients with metastatic renal cell carcinoma with sarcomatoid features

PubMed Central

Arjunan, Ananth; Wang, Hong; Saul, Melissa; Davar, Diwakar; Appleman, Leonard J.; Friedland, David; Parikh, Rahul A.

2017-01-01

Background High-dose interleukin-2 (HD IL-2) is used in the treatment of metastatic renal cell carcinoma (mRCC) and has an overall response rate (ORR) of 12–20% and a complete response rate (CR) of 8% in unselected populations with predominantly clear cell type renal cell carcinoma. Nearly 10–15% of patients with renal cell carcinoma exhibit sarcomatoid differentiation, a feature which correlates with a median overall survival (OS) of 9 months and overall poor prognosis. We report a single institution experience with 21 patients with mRCC with sarcomatoid features post-nephrectomy who were treated with HD IL-2. Methods Twenty one patients with mRCC with sarcomatoid features post-nephrectomy who underwent therapy with HD IL-2 were identified at the University of Pittsburgh Medical Center from 2004 to 2016. Baseline patient characteristics, HD IL-2 cycles, time to progression, and subsequent therapies were evaluated. OS and progression-free survival (PFS) in the cohort were calculated using the Kaplan-Meier method. Disease characteristics were evaluated for significance using the Fischer′s exact test and Wilcoxon rank sum test. Results Patients were predominantly Caucasian males with a median age of 54 years. A majority, 86% of these patients, had metastatic disease at time of initial presentation, primarily with lung and lymph node involvement. The ORR and CR with HD IL-2 was 10% and 5%, respectively. Initial localized disease presentation is the only variable that was significantly associated with response to HD IL-2 (p = 0.0158). Number of HD IL-2 doses did not correlate with response with a mean of 16.5 and 15.0 total doses in responders and non-responders, respectively (p = 0.53). Median PFS with HD IL-2 was 7.9 months (95% CI, 5.0–21.3). Median OS was 30.5 months (95% CI 13.3–57.66). Within the subset of patients who had progression on IL-2, median OS was 19.4 months (95% CI, 13.3–35.3). In patients who received second-line therapy, median PFS was 7.9 months (95% CI 2.4–10.2). Conclusion In patients with mRCC with sarcomatoid features, use of HD IL-2 was associated with a modest ORR and a higher survival compared to historical controls (patients with mRCC and sarcomatoid features). Thus, HD IL-2 may have a role in treating selected patients with mRCC with sarcomatoid features. PMID:29261796

High-dose interleukin 2 in patients with metastatic renal cell carcinoma with sarcomatoid features.

PubMed

Achkar, Tala; Arjunan, Ananth; Wang, Hong; Saul, Melissa; Davar, Diwakar; Appleman, Leonard J; Friedland, David; Parikh, Rahul A

2017-01-01

High-dose interleukin-2 (HD IL-2) is used in the treatment of metastatic renal cell carcinoma (mRCC) and has an overall response rate (ORR) of 12-20% and a complete response rate (CR) of 8% in unselected populations with predominantly clear cell type renal cell carcinoma. Nearly 10-15% of patients with renal cell carcinoma exhibit sarcomatoid differentiation, a feature which correlates with a median overall survival (OS) of 9 months and overall poor prognosis. We report a single institution experience with 21 patients with mRCC with sarcomatoid features post-nephrectomy who were treated with HD IL-2. Twenty one patients with mRCC with sarcomatoid features post-nephrectomy who underwent therapy with HD IL-2 were identified at the University of Pittsburgh Medical Center from 2004 to 2016. Baseline patient characteristics, HD IL-2 cycles, time to progression, and subsequent therapies were evaluated. OS and progression-free survival (PFS) in the cohort were calculated using the Kaplan-Meier method. Disease characteristics were evaluated for significance using the Fischer's exact test and Wilcoxon rank sum test. Patients were predominantly Caucasian males with a median age of 54 years. A majority, 86% of these patients, had metastatic disease at time of initial presentation, primarily with lung and lymph node involvement. The ORR and CR with HD IL-2 was 10% and 5%, respectively. Initial localized disease presentation is the only variable that was significantly associated with response to HD IL-2 (p = 0.0158). Number of HD IL-2 doses did not correlate with response with a mean of 16.5 and 15.0 total doses in responders and non-responders, respectively (p = 0.53). Median PFS with HD IL-2 was 7.9 months (95% CI, 5.0-21.3). Median OS was 30.5 months (95% CI 13.3-57.66). Within the subset of patients who had progression on IL-2, median OS was 19.4 months (95% CI, 13.3-35.3). In patients who received second-line therapy, median PFS was 7.9 months (95% CI 2.4-10.2). In patients with mRCC with sarcomatoid features, use of HD IL-2 was associated with a modest ORR and a higher survival compared to historical controls (patients with mRCC and sarcomatoid features). Thus, HD IL-2 may have a role in treating selected patients with mRCC with sarcomatoid features.

Trends and problems in CdS/Cu/x/S thin film solar cells - A review

NASA Astrophysics Data System (ADS)

Martinuzzi, S.

1982-03-01

The methods currently used to fabricate CdS/CuS solar cells are reviewed, along with comparisons of the effects on performance of the various preparation techniques. Attention is given to thermal evaporation, sputter, and chemical spray formation of the CdS layers, noting that most experience is presently with the evaporative and spray processes. CuS layers are formed in dip or wet process chemiplating, electroplating, vacuum deposition in flash and sputter modes, solid state reaction, or spray deposition. Any of the CuS film techniques can be used with any of the CdS layer processes, while spraying and sputtering are noted to offer the best alternatives for industrial production. Band profiles, I-V characteristics, photocurrent levels, and capacitance-voltage characteristics are outlined for the differently formed cells, and CdS/CuS and CdZnS/CuS cells are concluded to exhibit the highest performance features. Areas of improvement necessary to bring the cells to commercial status are discussed.

A dynamic cellular vertex model of growing epithelial tissues

NASA Astrophysics Data System (ADS)

Lin, Shao-Zhen; Li, Bo; Feng, Xi-Qiao

2017-04-01

Intercellular interactions play a significant role in a wide range of biological functions and processes at both the cellular and tissue scales, for example, embryogenesis, organogenesis, and cancer invasion. In this paper, a dynamic cellular vertex model is presented to study the morphomechanics of a growing epithelial monolayer. The regulating role of stresses in soft tissue growth is revealed. It is found that the cells originating from the same parent cell in the monolayer can orchestrate into clustering patterns as the tissue grows. Collective cell migration exhibits a feature of spatial correlation across multiple cells. Dynamic intercellular interactions can engender a variety of distinct tissue behaviors in a social context. Uniform cell proliferation may render high and heterogeneous residual compressive stresses, while stress-regulated proliferation can effectively release the stresses, reducing the stress heterogeneity in the tissue. The results highlight the critical role of mechanical factors in the growth and morphogenesis of epithelial tissues and help understand the development and invasion of epithelial tumors.

Influence of calcium on fungal growth, hyphal morphology and citric acid production in Aspergillus niger.

PubMed

Pera, L M; Callieri, D A

1997-01-01

Addition of 0.5 g/L CaCl2 to the fermentation medium lowered the final biomass dry mass by 35% and increased the uptake of phosphate and sucrose, and the production of citric acid by 15, 35 and 50%, respectively. In a medium deprived of Ca2+ the microorganism displayed both a pelleted and a filamentous form of growth, the hyphae being scarcely branched, without bulbous cells. An addition of Ca2+ induced a pelleted form of growth, highly branched hyphae and numerous bulbous cells. Bulbous cells growing in the presence of Ca2+ exhibited cell walls composed of laminated layers, and featured vesicles associated with the wall and/or the cell membrane, containing numerous inclusions. The cytotoxic effect of high concentrations of citric acid in the medium as well as an increase of the activity of N-acetyl-beta-D-glucosaminidase, a lytic enzyme, might be involved in these morphological changes.

Biophysical and Molecular Characterization of a Novel de novo KCNJ2 Mutation Associated with Andersen-Tawil Syndrome and CPVT Mimicry

PubMed Central

Barajas-Martinez, Hector; Hu, Dan; Ontiveros, Gustavo; Caceres, Gabriel; Desai, Mayurika; Burashnikov, Elena; Scaglione, Jorge; Antzelevitch, Charles

2010-01-01

Background Mutations in KCNJ2, the gene encoding the human inward rectifier potassium channel Kir2.1 (IK1 or IKir2.1), have been identified in Andersen-Tawil syndrome (ATS). ATS is a multisystem inherited disease exhibiting periodic paralysis, cardiac arrhythmias, and dysmorphic features at times mimicking catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods and Results Our proband displayed dysmorphic features including micrognathia, clinodactyly and syndactyly, and exhibited multiform extrasystoles and bidirectional ventricular tachycardia both at rest and during exercise testing. The patient’s symptoms continued following administration of nadolol, but subsided after treatment with flecainide. Molecular genetic screening revealed a novel heterozygous mutation (c.779G>C/p.R260P) in KCNJ2. Whole-cell patch-clamp studies conducted in TSA201 cells transfected with wild type human KCNJ2 cDNA (WT-KCNJ2) yielded robust IKir2.1, but no measurable current in cells expressing the R260P mutant. Co-expression of WT and R260P-KCNJ2 (heterozygous expression) yielded a markedly reduced inward IKir2.1 compared with WT alone (−36.5±9.8 pA/pF vs. −143.5±11.4 pA/pF, n=8 for both, P<0.001, respectively at −90 mV) indicating a strong dominant negative effect of the mutant. The outward component of IKir2.1 measured at −50 mV was also markedly reduced with the heterozygous expression vs. WT (0.52±5.5 pA/pF vs. 23.4±6.7 pA/pF, n=8 for both, P<0.001, respectively). Immunocytochemical analysis indicates that impaired trafficking of R260P-KCNJ2 channels. Conclusions We report a novel de novo KCNJ2 mutation associated with classical phenotypic features of ATS and CPVT mimicry. The R260P mutation produces a strong dominant negative effect leading to marked suppression of IK1 secondary to a trafficking defect. PMID:21148745

KSC-2014-3137

NASA Image and Video Library

2014-07-03

CAPE CANAVERAL, Fla. – The grand opening of the new Great Balls of Fire exhibit was held at NASA’s Kennedy Space Center Visitor Complex in Florida. The grand opening featured remarks by former NASA astronaut Tom Jones, and Therrin Protze, chief operating officer at Delaware North Parks and Resorts at the visitor complex. Informational displays about future NASA exploration missions are featured along the wall of the new exhibit. Great Balls of Fire shares the story of the origins of our solar system, asteroids and comets and their possible impacts and risks. The 1,500-square-foot exhibit, located in the East Gallery of the IMAX theatre at the visitor complex, features several interactive displays, real meteorites and replica asteroid models. The exhibit is a production of The Space Science Institute's National Center for Interactive Learning. It is a traveling exhibition that also receives funding from NASA and the National Science Foundation. Photo credit: NASA/Daniel Casper

X-ray Structural and Biological Evaluation of a Series of Potent and Highly Selective Inhibitors of Human Coronavirus Papain-like Proteases

PubMed Central

2015-01-01

Structure-guided design was used to generate a series of noncovalent inhibitors with nanomolar potency against the papain-like protease (PLpro) from the SARS coronavirus (CoV). A number of inhibitors exhibit antiviral activity against SARS-CoV infected Vero E6 cells and broadened specificity toward the homologous PLP2 enzyme from the human coronavirus NL63. Selectivity and cytotoxicity studies established a more than 100-fold preference for the coronaviral enzyme over homologous human deubiquitinating enzymes (DUBs), and no significant cytotoxicity in Vero E6 and HEK293 cell lines is observed. X-ray structural analyses of inhibitor-bound crystal structures revealed subtle differences between binding modes of the initial benzodioxolane lead (15g) and the most potent analogues 3k and 3j, featuring a monofluoro substitution at para and meta positions of the benzyl ring, respectively. Finally, the less lipophilic bis(amide) 3e and methoxypyridine 5c exhibit significantly improved metabolic stability and are viable candidates for advancing to in vivo studies. PMID:24568342

Inhibition of multidrug resistant Listeria monocytogenes by peptides isolated from combinatorial phage display libraries.

PubMed

Flachbartova, Z; Pulzova, L; Bencurova, E; Potocnakova, L; Comor, L; Bednarikova, Z; Bhide, M

2016-01-01

The aim of the study was to isolate and characterize novel antimicrobial peptides from peptide phage library with antimicrobial activity against multidrug resistant Listeria monocytogenes. Combinatorial phage-display library was used to affinity select peptides binding to the cell surface of multidrug resistant L. monocytogenes. After several rounds of affinity selection followed by sequencing, three peptides were revealed as the most promising candidates. Peptide L2 exhibited features common to antimicrobial peptides (AMPs), and was rich in Asp, His and Lys residues. Peptide L3 (NSWIQAPDTKSI), like peptide L2, inhibited bacterial growth in vitro, without any hemolytic or cytotoxic effects on eukaryotic cells. L1 peptide showed no inhibitory effect on Listeria. Structurally, peptides L2 and L3 formed random coils composed of α-helix and β-sheet units. Peptides L2 and L3 exhibited antimicrobial activity against multidrug resistant isolates of L. monocytogenes with no haemolytic or toxic effects. Both peptides identified in this study have the potential to be beneficial in human and veterinary medicine. Copyright © 2016 Elsevier GmbH. All rights reserved.

Regulation of the ovarian inflammatory response at ovulation by nuclear progesterone receptor.

PubMed

Akison, Lisa K; Robertson, Sarah A; Gonzalez, Macarena B; Richards, JoAnne S; Smith, C Wayne; Russell, Darryl L; Robker, Rebecca L

2018-06-01

The nuclear progesterone receptor (PGR) transcription factor is essential for ovulation; however, the exact mechanisms by which PGR controls ovulation are not known. The aim of this study was to determine whether PGR regulates inflammatory mediators in the ovary. Ovaries from mice lacking PGR (PRKO) and heterozygous PR+/- littermates were subjected to microarray analysis of a large panel of inflammatory genes. Immune cell subsets were detected by gene expression; and neutrophils by immunohistochemistry and chemotaxis assay. PRKO ovaries exhibited dysregulated expression of vasodilator (Edn1), cytokine (Il-6, Tgfb1), adhesion receptor (Cd34), apoptotic factor (Bax) and transcription factors (Nfkb2, Socs1, Stat3). Ptgs2 was also reduced in PRKO ovaries, but mRNA and protein were not different in granulosa cells. There were reduced neutrophils in ovaries of PRKO mice at ovulation; however, chemotaxis assays showed PRKO neutrophils migrate normally and that PRKO ovarian extracts exhibit chemotactic properties in vitro. Specific inflammatory mediators are altered in the ovaries of PRKO mice indicating that progesterone regulates features of inflammation at ovulation. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Simultaneous Increase in Open-Circuit Voltage and Efficiency of Fullerene-Free Solar Cells through Chlorinated Thieno[3,4- b ]thiophene Polymer Donor

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

Wang, Huan; Chao, Pengjie; Chen, Hui

The chlorinated polymer, PBTCl, has been found to be an efficient donor in nonfullerene polymer solar cells (PSCs), which showed a blue-shifted absorbance compared to that of its fluorine analogue (PTB7-th) and resulted in more complementary light absorption with a nonfullerene acceptor, such as ITIC. Meanwhile, chlorine substitution lowered the HOMO level of PBTCl, which increased the open-circuit voltage of the corresponding polymer-based devices. The 2D GIWAXS analysis illustrated that the PBTCl/ITIC blend film exhibited a “face-on” orientation and scattering features of both PBTCl and ITIC, suggesting that the blend of PBTCl and ITIC was phase-separated and formed individual crystallinemore » domains of the donor and acceptor, which promoted charge transfer in the bicontinuous film and eventually elevated the solar energy conversion efficiency. The PBTCl-based nonfullerene PSC exhibited a maximum PCE of 7.57% with a Voc of 0.91 V, which was an approximately 13% increasing in the PCE compared to that of the fluorine-analogue-based device.« less

Visual feature integration with an attention deficit.

PubMed

Arguin, M; Cavanagh, P; Joanette, Y

1994-01-01

Treisman's feature integration theory proposes that the perception of illusory conjunctions of correctly encoded visual features is due to the failure of an attentional process. This hypothesis was examined by studying brain-damaged subjects who had previously been shown to have difficulty in attending to contralesional stimulation. These subjects exhibited a massive feature integration deficit for contralesional stimulation relative to ipsilesional displays. In contrast, both normal age-matched controls and brain-damaged subjects who did not exhibit any evidence of an attention deficit showed comparable feature integration performance with left- and right-hemifield stimulation. These observations indicate the crucial function of attention for visual feature integration in normal perception.

Microscopic and ultrastructural features in Wolcott-Rallison syndrome, a permanent neonatal diabetes mellitus: about two autopsy cases.

PubMed

Collardeau-Frachon, Sophie; Vasiljevic, Alexandre; Jouvet, Anne; Bouvier, Raymonde; Senée, Valérie; Nicolino, Marc

2015-11-01

Wolcott-Rallison syndrome (WRS) is a rare autosomal recessive disorder characterized by the association of permanent neonatal or early-infancy insulin-dependent diabetes, multiple bone dysplasia, hepatic dysfunction, and growth retardation. All clinical manifestations result from gene mutations encoding pancreatic endoplasmic reticulum eIF2 α kinase (PERK), an endoplasmic reticulum transmembrane protein that plays a role in the unfolded protein response. Histological and ultrastructural lesions of bone and pancreas have been described in animal models and WRS patients. However, histological and ultrastructural findings of other organs, especially of the liver, are lacking. Autopsy specimens from two pediatric patients with WRS were analyzed. An immunohistochemical study was performed on the pancreas. An ultrastructural study was realized from samples of liver, pancreas, kidney, and myocardium. Our findings were compared with those of the literature and correlated with the molecular data. Hepatocytes and pancreatic exocrine cells exhibited very peculiar features of necrosis suggestive of secondary changes because of endoplasmic reticulum overload. Steatosis occurred in renal tubular cells, hepatocytes, and myocardial fibers. Abnormal mitochondria were noted in renal and myocardial fibers. Pancreas islets were characterized by a marked reduction in the number of insulin-secreting β cells. The histological and ultrastructural features that occur in WRS are directly or indirectly linked to endoplasmic reticulum (ER) dysfunction and can explain the peculiar phenotype of this syndrome. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cellular Scale Anisotropic Topography Guides Schwann Cell Motility

PubMed Central

Mitchel, Jennifer A.; Hoffman-Kim, Diane

2011-01-01

Directed migration of Schwann cells (SC) is critical for development and repair of the peripheral nervous system. Understanding aspects of motility specific to SC, along with SC response to engineered biomaterials, may inform strategies to enhance nerve regeneration. Rat SC were cultured on laminin-coated microgrooved poly(dimethyl siloxane) platforms that were flat or presented repeating cellular scale anisotropic topographical cues, 30 or 60 µm in width, and observed with timelapse microscopy. SC motion was directed parallel to the long axis of the topography on both the groove floor and the plateau, with accompanying differences in velocity and directional persistence in comparison to SC motion on flat substrates. In addition, feature dimension affected SC morphology, alignment, and directional persistence. Plateaus and groove floors presented distinct cues which promoted differential motility and variable interaction with the topographical features. SC on the plateau surfaces tended to have persistent interactions with the edge topography, while SC on the groove floors tended to have infrequent contact with the corners and walls. Our observations suggest the capacity of SC to be guided without continuous contact with a topographical cue. SC exhibited a range of distinct motile morphologies, characterized by their symmetry and number of extensions. Across all conditions, SC with a single extension traveled significantly faster than cells with more or no extensions. We conclude that SC motility is complex, where persistent motion requires cellular asymmetry, and that anisotropic topography with cellular scale features can direct SC motility. PMID:21949703

Benign and Malignant Brenner Tumors Show an Absence of TERT Promoter Mutations That Are Commonly Present in Urothelial Carcinoma.

PubMed

Khani, Francesca; Diolombi, Mairo L; Khattar, Pallavi; Huang, Weihua; Fallon, John T; Epstein, Jonathan I; Zhong, Minghao

2016-09-01

Brenner tumors are uncommon ovarian neoplasms, which have morphologic and immunophenotypical features of transitional cell (urothelial) differentiation. The origin of Brenner tumors is perplexing, but they are believed to arise from transitional cell metaplasia occurring within the ovary and/or fallopian tube, although it is controversial whether this metaplasia is truly along transitional cell lines. Recently, TERT promoter mutations have been identified in urothelial carcinoma (UC) with high frequency (approximately 70%), and the current literature suggests a potential diagnostic and/or prognostic role of these mutations in UC. Molecular evidence supporting that Brenner tumors represent neoplasms exhibiting transitional cell differentiation is scant. To explore this further, we investigated a series of 19 Brenner tumors of the ovary (15 benign and 4 malignant) for the presence of TERT promoter mutations after genomic DNA extraction from formalin-fixed paraffin-embedded tissue blocks and standard polymerase chain reaction sequencing. TERT promoter mutations were not identified in any of the cases (0/19). The absence of TERT promoter mutations in Brenner tumors suggests that despite the morphologic and some immunophenotypical resemblance to non-neoplastic and neoplastic transitional epithelium, Brenner tumors may exhibit a molecularly distinct pathogenesis. The findings also may portend diagnostic utility in rare cases wherein it is difficult to distinguish a primary malignant Brenner tumor of the ovary from metastatic UC.

Disruption of NBS1 gene leads to early embryonic lethality in homozygous null mice and induces specific cancer in heterozygous mice

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

Kurimasa, Akihiro; Burma, Sandeep; Henrie, Melinda

2002-04-15

Nijmegen breakage syndrome (NBS) is a rare autosomal recessive chromosome instability syndrome characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition, with cellular features similar to that of ataxia telangiectasia (AT). NBS results from mutations in the mammalian gene Nbs1 that codes for a 95-kDa protein called nibrin, NBS1, or p95. To establish an animal model for NBS, we attempted to generate NBS1 knockout mice. However, NBS1 gene knockouts were lethal at an early embryonic stage. NBS1 homozygous(-/-) blastocyst cells cultured in vitro showed retarded growth and subsequently underwent growth arrest within 5 days of culture. Apoptosis, assayed by TUNELmore » staining, was observed in NBSI homozygous(-/-) blastocyst cells cultured for four days. NBSI heterozygous(+/-) mice were normal, and exhibited no specific phenotype for at least one year. However, fibroblast cells from NBSI heterozygous(+/-) mice displayed an enhanced frequency of spontaneous transformation to anchorage-independent growth as compared to NBS1 wild-type(+/+) cells. Furthermore, heterozygous(+/-) mice exhibited a high incidence of hepatocellular carcinoma after one year compared to wild-type mice, even though no significant differences in the incidence of other tumors such as lung adenocarcinoma and lymphoma were observed. Taken together, these results strongly suggest that NBS1 heterozygosity and reduced NBSI expression induces formation of specific tumors in mice.« less

ATP6AP2 over-expression causes morphological alterations in the hippocampus and in hippocampus-related behaviour.

PubMed

Bracke, A; Schäfer, S; von Bohlen Und Halbach, V; Klempin, F; Bente, K; Bracke, K; Staar, D; van den Brandt, J; Harzsch, S; Bader, M; Wenzel, U O; Peters, J; von Bohlen Und Halbach, O

2018-02-23

The (pro)renin receptor [(P)RR], also known as ATP6AP2 [ATPase 6 accessory protein 2], is highly expressed in the brain. ATP6AP2 plays a role in early brain development, adult hippocampal neurogenesis and in cognitive functions. Lack of ATP6AP2 has deleterious effects, and mutations of ATP6AP2 in humans are associated with, e.g. X-linked intellectual disability. However, little is known about the effects of over-expression of ATP6AP2 in the adult brain. We hypothesized that mice over-expressing ATP6AP2 in the brain might exhibit altered neuroanatomical features and behavioural responses. To this end, we investigated heterozygous transgenic female mice and confirmed increased levels of ATP6AP2 in the brain. Our data show that over-expression of ATP6AP2 does not affect adult hippocampal neurogenesis, exercise-induced cell proliferation, or dendritic spine densities in the hippocampus. Only a reduced ventricular volume on the gross morphological level was found. However, ATP6AP2 over-expressing mice displayed altered exploratory behaviour with respect to the hole-board and novel object recognition tests. Moreover, primary adult hippocampal neural stem cells over-expressing ATP6AP2 exhibit a faster cell cycle progression and increased cell proliferation. Together, in contrast to the known deleterious effects of ATP6AP2 depletion, a moderate over-expression results in moderate behavioural changes and affects cell proliferation rate in vitro.

Hemocytes of the palaemonids Macrobrachium rosenbergii and M. acanthurus, and of the penaeid Penaeus paulensis.

PubMed

Gargioni, R; Barracco, M A

1998-06-01

The hemocytes of two palaemonids and one penaeid were characterized using light and transmission electron microscopy (TEM). The blood cells in all three species were classified as hyaline hemocytes (HH), small granule hemocytes (SGH), and large granule hemocytes (LGH). The HH are unstable hemocytes with a characteristic high nucleo-cytoplasmic ratio. Their cytoplasm appears particularly dense and has from few to numerous granules that often exhibit a typical striated substructure. In both palaemonids, the great majority of the HH contain numerous granules, whereas in Penaeus paulensis, a small number of these cells have few or no granules. The cytoplasm of some HH of the penaeid exhibits typical electron-dense deposits. The granulocytes, LGH and SGH, contain abundant electron-dense granules that are usually smaller in the SGH. In both hemocyte types, the cytosol, but not the granules, is rich in carbohydrates (PAS positive) and numerous vesicles contain acid phosphatase (Gomori reactive). In all studied shrimps, the SGH and LGH were actively phagocytic when examined on blood cell monolayers incubated with the yeast Saccharomyces cerevisiae. A few mitotic figures (less than 1%) were observed in the granulocytes of P. paulensis, but not in the palaemonids. SGH is the main circulating blood cell type in both palaemonids, whereas HH is predominant in the penaeid. Based on morphological and functional features, it appears that the hyaline and the granular hemocytes of the three shrimp species represent different cell lineages.

The Osteogenic Niche Promotes Early-Stage Bone Colonization of Disseminated Breast Cancer Cells

PubMed Central

Wang, Hai; Yu, Cuijuan; Gao, Xia; Welte, Thomas; Muscarella, Aaron M.; Tian, Lin; Zhao, Hong; Zhao, Zhen; Du, Shiyu; Tao, Jianning; Lee, Brendan; Westbrook, Thomas F.; Wong, Stephen T. C.; Jin, Xin; Rosen, Jeffrey M.; Osborne, C. Kent; Zhang, Xiang H.-F.

2014-01-01

Summary Breast cancer bone micrometastases can remain asymptomatic for years before progressing into overt lesions. The biology of this process, including the microenvironment niche and supporting pathways, is unclear. We find that bone micrometastases predominantly reside in a niche that exhibits features of osteogenesis. Niche interactions are mediated by heterotypic adherens junctions (hAJs) involving cancer-derived E-cadherin and osteogenic N-cadherin, the disruption of which abolishes niche-conferred advantages. We further elucidate that hAJ activates the mTOR pathway in cancer cells, which drives the progression from single cells to micrometastases. Human datasets analyses support the roles of AJ and the mTOR pathway in bone colonization. Our study illuminates the initiation of bone colonization, and provides potential therapeutic targets to block progression toward osteolytic metastases. Significance In advanced stages, breast cancer bone metastases are driven by paracrine crosstalk among cancer cells, osteoblasts, and osteoclasts, which constitute a vicious osteolytic cycle. Current therapies targeting this process limit tumor progression, but do not improve patient survival. On the other hand, bone micrometastases may remain indolent for years before activating the vicious cycle, providing a therapeutic opportunity to prevent macrometastases. Here, we show that bone colonization is initiated in a microenvironment niche exhibiting active osteogenesis. Cancer and osteogenic cells form heterotypic adherens junctions, which enhance mTOR activity and drive early-stage bone colonization prior to osteolysis. These results reveal a strong connection between osteogenesis and micrometastasis and suggest potential therapeutic targets to prevent bone macrometastases. PMID:25600338

Loss of Asxl1 leads to myelodysplastic syndrome-like disease in mice.

PubMed

Wang, Jiapeng; Li, Zhaomin; He, Yongzheng; Pan, Feng; Chen, Shi; Rhodes, Steven; Nguyen, Lihn; Yuan, Jin; Jiang, Li; Yang, Xianlin; Weeks, Ophelia; Liu, Ziyue; Zhou, Jiehao; Ni, Hongyu; Cai, Chen-Leng; Xu, Mingjiang; Yang, Feng-Chun

2014-01-23

ASXL1 is mutated/deleted with high frequencies in multiple forms of myeloid malignancies, and its alterations are associated with poor prognosis. De novo ASXL1 mutations cause Bohring-Opitz syndrome characterized by multiple congenital malformations. We show that Asxl1 deletion in mice led to developmental abnormalities including dwarfism, anophthalmia, and 80% embryonic lethality. Surviving Asxl1(-/-) mice lived for up to 42 days and developed features of myelodysplastic syndrome (MDS), including dysplastic neutrophils and multiple lineage cytopenia. Asxl1(-/-) mice had a reduced hematopoietic stem cell (HSC) pool, and Asxl1(-/-) HSCs exhibited decreased hematopoietic repopulating capacity, with skewed cell differentiation favoring granulocytic lineage. Asxl1(+/-) mice also developed mild MDS-like disease, which could progress to MDS/myeloproliferative neoplasm, demonstrating a haploinsufficient effect of Asxl1 in the pathogenesis of myeloid malignancies. Asxl1 loss led to an increased apoptosis and mitosis in Lineage(-)c-Kit(+) (Lin(-)c-Kit(+)) cells, consistent with human MDS. Furthermore, Asxl1(-/-) Lin(-)c-Kit(+) cells exhibited decreased global levels of H3K27me3 and H3K4me3 and altered expression of genes regulating apoptosis (Bcl2, Bcl2l12, Bcl2l13). Collectively, we report a novel ASXL1 murine model that recapitulates human myeloid malignancies, implying that Asxl1 functions as a tumor suppressor to maintain hematopoietic cell homeostasis. Future work is necessary to clarify the contribution of microenvironment to the hematopoietic phenotypes observed in the constitutional Asxl1(-/-) mice.

High Q-factor metasurfaces based on miniaturized asymmetric single split resonators

NASA Astrophysics Data System (ADS)

Al-Naib, Ibraheem A. I.; Jansen, Christian; Koch, Martin

2009-04-01

We introduce asymmetric single split rectangular resonators as bandstop metasurfaces, which exhibit very high Q-factors in combination with low passband losses and a small electrical footprint. The effect of the degree of asymmetry on the frequency response is thoroughly studied. Furthermore, complementary structures, which feature a bandpass behavior, were derived by applying Babinet's principle and investigated with regards to their transmission characteristics. In future, asymmetric single split rectangular resonators could provide efficient unit cells for frequency selective surface devices, such as thin-film sensors or high performance filters.

SerpinB1 Promotes Pancreatic β Cell Proliferation

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

El Ouaamari, Abdelfattah; Dirice, Ercument; Gedeon, Nicholas

2016-01-01

Compensatory β-cell growth in response to insulin resistance is a common feature in diabetes. We recently reported that liver-derived factors participate in this compensatory response in the liver insulin receptor knockout (LIRKO) mouse, a model of significant islet hyperplasia. Here we show that serpinB1 is a liver-derived secretory protein that controls β-cell proliferation. SerpinB1 is abundant in the hepatocyte secretome and sera derived from LIRKO mice. SerpinB1 and small molecule compounds that partially mimic serpinB1 activity enhanced proliferation of zebrafish, mouse and human β-cells. We report that serpinB1-induced β-cell replication requires protease inhibition activity and mice lacking serpinB1 exhibit attenuatedmore » β-cell replication in response to insulin resistance. Finally, SerpinB1-treatment of islets modulated signaling proteins in growth and survival pathways such as MAPK, PKA and GSK3. Together, these data implicate SerpinB1 as a protein that can potentially be harnessed to enhance functional β-cell mass in patients with diabetes.« less

Comparison of Cellular Alterations in Fat Cells Harvested With Laser-Assisted Liposuction and Suction-Assisted Liposuction.

PubMed

Yildiz, Kemalettin; Taşli, Pakize Neslihan; Şahin, Fikrettin; Güneren, Ethem

2016-05-01

The aim of the present study was to evaluate the viability and proliferative capacity of adipose-derived stem cells obtained by laser-assisted liposuction (LAL). Fat tissue was obtained from 7 male patients treated surgically for gynecomastia. On one side, harvesting was made before LAL, while it was implemented after LAL on the contralateral side. Viability, cell surface antigens, pluripotency, and apoptosis were assessed and compared in these samples. Cells harvested before and after LAL did not exhibit any significant difference in terms of surface cell markers. Number of viable stem cells was lower initially after exposure to laser, while this difference was reversed at the end of 72 hours. Genetic indicators of cellular differentiation were similar in both groups. Apoptosis indicators were increased remarkably after laser exposure in the first 24 hours, but this increase was absent 72 hours after LAL procedure. The authors' results have promising clinical relevance since mesenchymal stem cells harvested during LAL have maintained appropriate cellular features to be used for autologous fat transfer and fat grafting.

Relating cell shape and mechanical stress in a spatially disordered epithelium using a vertex-based model

PubMed Central

Nestor-Bergmann, Alexander; Goddard, Georgina; Woolner, Sarah; Jensen, Oliver E

2018-01-01

Abstract Using a popular vertex-based model to describe a spatially disordered planar epithelial monolayer, we examine the relationship between cell shape and mechanical stress at the cell and tissue level. Deriving expressions for stress tensors starting from an energetic formulation of the model, we show that the principal axes of stress for an individual cell align with the principal axes of shape, and we determine the bulk effective tissue pressure when the monolayer is isotropic at the tissue level. Using simulations for a monolayer that is not under peripheral stress, we fit parameters of the model to experimental data for Xenopus embryonic tissue. The model predicts that mechanical interactions can generate mesoscopic patterns within the monolayer that exhibit long-range correlations in cell shape. The model also suggests that the orientation of mechanical and geometric cues for processes such as cell division are likely to be strongly correlated in real epithelia. Some limitations of the model in capturing geometric features of Xenopus epithelial cells are highlighted. PMID:28992197

Dynamic Interactions Between Cancer Stem Cells And Their Stromal Partners.

PubMed

Park, Tea Soon; Donnenberg, Vera S; Donnenberg, Albert D; Zambidis, Elias T; Zimmerlin, Ludovic

2014-03-01

The cancer stem cell (CSC) paradigm presumes the existence of self-renewing cancer cells capable of regenerating all tumor compartments and exhibiting stem cell-associated phenotypes. Recent interpretations of the CSC hypothesis envision stemness as a dynamic trait of tumor-initiating cells rather than a defined and unique cell type. Bidirectional crosstalk between the tumor microenvironment and the cancer bulk is well described in the literature and the tumor-associated stroma, vasculature and immune infiltrate have all been implicated as direct contributors to tumor development. These non-neoplastic cell types have also been shown to organize specific niches within the tumor bulk where they can control the intra-tumor CSC content and alter the fate of CSCs and tumor progenitors during tumorigenesis to acquire phenotypic features for invasion, metastasis and dormancy. Despite the complexity of the tumor-stroma interactome, novel therapeutic approaches envision combining tumor-ablative treatment with manipulation of the tumor microenvironment. We will review the currently available literature that provides clues about the complex cellular network that regulate the CSC phenotype and its niches during tumor progression.

Disseminated Hemangiosarcoma in a Juvenile Rhesus Macaque (Macaca mulatta)

PubMed Central

Beck, Amanda P; Gray, Stanton B; Chaffee, Beth K

2016-01-01

Hemangiosarcoma is a malignant tumor of vascular endothelial origin that is sporadically reported in rhesus macaques. This report describes the clinicopathologic features of a 1-y-old rhesus macaque with spontaneous disseminated hemangiosarcoma that originally presented as a focal cutaneous mass. Histopathologic examination of multiple tumor foci revealed regions in which the neoplastic cells formed diffuse sheets, as well as the well-defined vascular channels typically associated with hemangiosarcoma. Multiple endothelial cell immunomarkers were used to confirm the diagnosis in this rhesus macaque. The tumor exhibited staining properties consistent with those seen in domestic animals and humans. In addition, to our knowledge, this animal represents the youngest case of any form of spontaneous hemangiosarcoma reported in the rhesus macaque to date. PMID:27298251

Disseminated Hemangiosarcoma in a Juvenile Rhesus Macaque (Macaca mulatta).

PubMed

Beck, Amanda P; Gray, Stanton B; Chaffee, Beth K

2016-01-01

Hemangiosarcoma is a malignant tumor of vascular endothelial origin that is sporadically reported in rhesus macaques. This report describes the clinicopathologic features of a 1-y-old rhesus macaque with spontaneous disseminated hemangiosarcoma that originally presented as a focal cutaneous mass. Histopathologic examination of multiple tumor foci revealed regions in which the neoplastic cells formed diffuse sheets, as well as the well-defined vascular channels typically associated with hemangiosarcoma. Multiple endothelial cell immunomarkers were used to confirm the diagnosis in this rhesus macaque. The tumor exhibited staining properties consistent with those seen in domestic animals and humans. In addition, to our knowledge, this animal represents the youngest case of any form of spontaneous hemangiosarcoma reported in the rhesus macaque to date.

'The genetic analysis of functional connectomics in Drosophila'

PubMed Central

Meinertzhagen, Ian A.; Lee, Chi-Hon

2014-01-01

Fly and vertebrate nervous systems share many organization characteristics, such as layers, columns and glomeruli, and utilize similar synaptic components, such ion channels and receptors. Both also exhibit similar network features. Recent technological advances, especially in electron microscopy, now allow us to determine synaptic circuits and identify pathways cell-by-cell, as part of the fly’s connectome. Genetic tools provide the means to identify synaptic components, as well as to record and manipulate neuronal activity, adding function to the connectome. This review discusses technical advances in these emerging areas of functional connectomics, offering prognoses in each and identifying the challenges in bridging structural connectomics to molecular biology and synaptic physiology, thereby determining fundamental computation mechanisms that underlie behaviour. PMID:23084874

Template method for fabricating interdigitate p-n heterojunction for organic solar cell

PubMed Central

2012-01-01

Anodic aluminum oxide (AAO) templates are used to fabricate arrays of poly(3-hexylthiophene) (P3HT) pillars. This technique makes it possible to control the dimensions of the pillars, namely their diameters, intervals, and heights, on a tens-of-nanometer scale. These features are essential for enhancing carrier processes such as carrier generation, exciton diffusion, and carrier dissociation and transport. An interdigitated p-n junction between P3HT pillars and fullerene (C60) exhibits a photovoltaic effect. Although the device properties are still preliminary, the experimental results indicate that an AAO template is an effective tool with which to develop organic solar cells because highly regulated nanostructures can be produced on large areas exceeding 100 mm2. PMID:22908897

Isodicentric Y mosaicism involving a 46, XX cell line: Implications for management.

PubMed

Hipp, Lauren E; Mohnach, Lauren H; Wei, Sainan; Thomas, Inas H; Elhassan, Maha E; Sandberg, David E; Quint, Elisabeth H; Keegan, Catherine E

2016-01-01

Carriers of isodicentric Y (idicY) mosaicism exhibit a wide range of clinical features, including short stature, gonadal abnormalities, and external genital anomalies. However, the phenotypic spectrum for individuals carrying an idicY and a 46, XX cell line is less clearly defined. A more complete description of the phenotype related to idicY is thus essential to guide management related to pubertal development, fertility, and gonadoblastoma risk in mosaic carriers. Findings from the evaluation of twin females with an abnormal karyotype, 48, XX, +idic(Yq) x2/47, XX, +idic(Yq)/46, XX, are presented to highlight the importance of interdisciplinary care in the management of multifaceted disorders of sex development. © 2015 Wiley Periodicals, Inc.

A general synthetic strategy and the anti-proliferation properties on prostate cancer cell lines for natural phenylethanoid glycosides.

PubMed

Mulani, Shaheen K; Guh, Jih-Hwa; Mong, Kwok-Kong Tony

2014-05-14

A general strategy for the synthesis of phenylethanoid glycosides (PhG) including echinacoside 1, acteoside 2, calceolarioside-A 3 and calceolarioside-B 4 is reported. The strategy features the application of low substrate concentration glycosylation and N-formyl morpholine modulated glycosylation methods for the construction of 1,2-trans β- and α-glycosidic bonds. The reported strategy does not invoke the use of the participatory acyl protecting function, which is incompatible with the ester function present in target PhG compounds. A preliminary study of the anti-proliferation properties of the PhG compounds 1–4 was performed; the acteoside 2 exhibited the best inhibition on the prostatic cancer cell proliferation.

Direct head-to-head comparison of cationic liposome-mediated gene delivery to mesenchymal stem/stromal cells of different human sources: a comprehensive study.

PubMed

Boura, Joana S; Santos, Francisco Dos; Gimble, Jeffrey M; Cardoso, Carla M P; Madeira, Catarina; Cabral, Joaquim M S; Silva, Cláudia Lobato da

2013-02-01

Nonviral gene delivery to human mesenchymal stem/stromal cells (MSC) can be considered a very promising strategy to improve their intrinsic features, amplifying the therapeutic potential of these cells for clinical applications. In this work, we performed a comprehensive comparison of liposome-mediated gene transfer efficiencies to MSC derived from different human sources-bone marrow (BM MSC), adipose tissue-derived cells (ASC), and umbilical cord matrix (UCM MSC). The results obtained using a green fluorescent protein (GFP)-encoding plasmid indicated that MSC isolated from BM and UCM are more amenable to genetic modification when compared to ASC as they exhibited superior levels of viable, GFP(+) cells 48 hr post-transfection, 58 ± 7.1% and 54 ± 3.8%, respectively, versus 33 ± 4.7%. For all cell sources, high cell recoveries (≈50%) and viabilities (>85%) were achieved, and the transgene expression was maintained for 10 days. Levels of plasmid DNA uptake, as well as kinetics of transgene expression and cellular division, were also determined. Importantly, modified cells were found to retain their characteristic immunophenotypic profile and multilineage differentiation capacity. By using the lipofection protocol optimized herein, we were able to maximize transfection efficiencies to human MSC (maximum of 74% total GFP(+) cells) and show that lipofection is a promising transfection strategy for MSC genetic modification, especially when a transient expression of a therapeutic gene is required. Importantly, we also clearly demonstrated that intrinsic features of MSC from different sources should be taken into consideration when developing and optimizing strategies for MSC engineering with a therapeutic gene.

[Clinicopathologic study of sinonasal teratocarcinosarcoma and its contrast with olfactory neuroblastoma].

PubMed

Li, Xue; Liu, Hong-Gang; Xie, Xin-Ji; Han, Yi-Ding; Li, Ming

2008-07-01

To study the clinicopathologic features, diagnosis and differential diagnosis of sinonasal teratocarcinosarcoma (SNTCS) and olfactory neuroblastoma (ONB), and to discuss the histogenesis and possible relationship between SNTCS and ONB. Seven cases of SNTCS and 34 cases of ONB were retrieved from the pathological archives together with one case each of malignant teratoma and immature embryonic tissue at 8 weeks were collected from Beijing Tongren Hospital. The clinicopathologic features were analyzed and immunohistochemical staining was performed on paraffin sections. Six of the SNTCS patients were male and one was female. The patients age range was 25 to 69 years (mean age 46). Four cases were initial presentation and three were recurrences. Histologically, the tumor shows multiple tissue components derived from three germ layers. There were mixture of teratoma-like tissue and carcinosarcoma. The components include fetal clear cell squamous epithelium derived from ectoderm. Glandular and tubular structures and ciliated columnar epithelium derived from endoderm. Fibroblasts, striated muscle, smooth muscle, cartilage and osteoid matrix derived from mesoderm. The carcinoma component exhibited mostly adenocarcinoma and squamous cell carcinoma, whereas the sarcoma component mostly exhibited rhabdomyosarcoma, leiomyosarcoma, and fibrosarcoma. In addition, carcinoid, and primitive mesenchymal tissue and the ONB component were also seen. The morphological characteristics of SNTCS comprised fetal clear cell squamous epithelium, carcinosarcoma and the ONB component. By immunohistochemistry, the epithelial component and cells with epithelium differentiation were positive for cytokeratin (pan) and EMA. The ONB component was positive for Syn, NSE, CD99, NF and CgA to different degrees. Neurofibril bundles were positive for S-100, and Flexner-Wintersteiner rosettes expressed cytokeratin (pan) and EMA. The spindle cells expressed vimentin, SMA, desmin, myosin and myoglobin. The primitive mesenchymal tissue expressed vimentin, and the mucoid materials and glycogen were positive for PAS. GFAP was negative in all cases. The 34 cases of ONB, included 18 men and 16 women, the age ranged from 12 to 72 years (mean 42.8 years). Microscopically, the tumor shows epithelial nests, net of angioma-like fibrous connective tissues, small round and spindle cells, glandular, squamous-like cells, and cells of rhabdomyoblastic differentiation, Homer-Wright and Flexner rosette, bundles of neurofibrils, etc. NSE and CgA were expressed in small cells. S-100 protein was positive in the areas of bunches of neurofibril. Cytokeratin (pan) was positive in epithelial cells. Myoglobin was positive in the cells of rhabdomyoblastic differentiation. The single case of immature malignant teratoma exhibited primitive nerve tissue, but fetal clear cell squamous epithelium was not found. In the immature embryonic tissue, rudimentary organs were formed, with fetal clear cell squamous epithelium lining present on the nasal and oral cavities surface. SNTCS is a rare and aggressive malignant neoplasm. Most of ONB are low-grade malignant tumors. Morphological differences are the most important basis to make differentiate SNTCS from ONB. As SNTCS may demonstrate a multiplicity of structures and pleomorphism, inadequate sampling at biopsy, therefore, may lead to errors in diagnosis. No evidence show that SNTCS are derived from germ cells and sinonasal teratoid carcinosarcoma may be a more proper name. SNTCS probably arises from primitive totipotential cells of olfactory/sinonasal membrane, and the relationship between SNTCS and ONB needs further study.

On the relationship between the dynamic behavior and nanoscale staggered structure of the bone

NASA Astrophysics Data System (ADS)

Qwamizadeh, Mahan; Zhang, Zuoqi; Zhou, Kun; Zhang, Yong Wei

2015-05-01

Bone, a typical load-bearing biological material, composed of ordinary base materials such as organic protein and inorganic mineral arranged in a hierarchical architecture, exhibits extraordinary mechanical properties. Up to now, most of previous studies focused on its mechanical properties under static loading. However, failure of the bone occurs often under dynamic loading. An interesting question is: Are the structural sizes and layouts of the bone related or even adapted to the functionalities demanded by its dynamic performance? In the present work, systematic finite element analysis was performed on the dynamic response of nanoscale bone structures under dynamic loading. It was found that for a fixed mineral volume fraction and unit cell area, there exists a nanoscale staggered structure at some specific feature size and layout which exhibits the fastest attenuation of stress waves. Remarkably, these specific feature sizes and layouts are in excellent agreement with those experimentally observed in the bone at the same scale, indicating that the structural size and layout of the bone at the nanoscale are evolutionarily adapted to its dynamic behavior. The present work points out the importance of dynamic effect on the biological evolution of load-bearing biological materials.

Tumor SHB gene expression affects disease characteristics in human acute myeloid leukemia.

PubMed

Jamalpour, Maria; Li, Xiujuan; Cavelier, Lucia; Gustafsson, Karin; Mostoslavsky, Gustavo; Höglund, Martin; Welsh, Michael

2017-10-01

The mouse Shb gene coding for the Src Homology 2-domain containing adapter protein B has recently been placed in context of BCRABL1-induced myeloid leukemia in mice and the current study was performed in order to relate SHB to human acute myeloid leukemia (AML). Publicly available AML databases were mined for SHB gene expression and patient survival. SHB gene expression was determined in the Uppsala cohort of AML patients by qPCR. Cell proliferation was determined after SHB gene knockdown in leukemic cell lines. Despite a low frequency of SHB gene mutations, many tumors overexpressed SHB mRNA compared with normal myeloid blood cells. AML patients with tumors expressing low SHB mRNA displayed longer survival times. A subgroup of AML exhibiting a favorable prognosis, acute promyelocytic leukemia (APL) with a PMLRARA translocation, expressed less SHB mRNA than AML tumors in general. When examining genes co-expressed with SHB in AML tumors, four other genes ( PAX5, HDAC7, BCORL1, TET1) related to leukemia were identified. A network consisting of these genes plus SHB was identified that relates to certain phenotypic characteristics, such as immune cell, vascular and apoptotic features. SHB knockdown in the APL PMLRARA cell line NB4 and the monocyte/macrophage cell line MM6 adversely affected proliferation, linking SHB gene expression to tumor cell expansion and consequently to patient survival. It is concluded that tumor SHB gene expression relates to AML survival and its subgroup APL. Moreover, this gene is included in a network of genes that plays a role for an AML phenotype exhibiting certain immune cell, vascular and apoptotic characteristics.

L-DOPA decarboxylase mRNA levels provide high diagnostic accuracy and discrimination between clear cell and non-clear cell subtypes in renal cell carcinoma.

PubMed

Papadopoulos, Emmanuel I; Petraki, Constantina; Gregorakis, Alkiviadis; Chra, Eleni; Fragoulis, Emmanuel G; Scorilas, Andreas

2015-06-01

Renal cell carcinoma (RCC) is the most frequent type of kidney cancer. RCC patients frequently present with arterial hypertension due to various causes, including intrarenal dopamine deficiency. L-DOPA decarboxylase (DDC) is the gene encoding the enzyme that catalyzes the biosynthesis of dopamine in humans. Several studies have shown that the expression levels of DDC are significantly deregulated in cancer. Thus, we herein sought to analyze the mRNA levels of DDC and evaluate their clinical significance in RCC. DDC levels were analyzed in 58 surgically resected RCC tumors and 44 adjacent non-cancerous renal tissue specimens via real-time PCR. Relative levels of DDC were estimated by applying the 2(-ΔΔC)T method, while their diagnostic accuracy and correlation with the clinicopathological features of RCC tumors were assessed by comprehensive statistical analysis. DDC mRNA levels were found to be dramatically downregulated (p<0.001) in RCC tumors, exhibiting remarkable diagnostic accuracy as assessed by ROC curve analysis (AUC: 0.910; p<0.001) and logistic regression (OR: 0.678; p=0.001). Likewise, DDC was found to be differentially expressed between clear cell RCC and the group of non-clear cell subtypes (p=0.001) consisted of papillary and chromophobe RCC specimens. Furthermore, a statistically significant inverse correlation was also observed when the mRNA levels of DDC were analyzed in relation to tumor grade (p=0.049). Our data showed that DDC constitutes a highly promising molecular marker for RCC, exhibiting remarkable diagnostic accuracy and potential to discriminate between clear cell and non-clear cell histological subtypes of RCC. Copyright © 2015. Published by Elsevier Inc.

Genetically heterogeneous glioblastoma recurring with disappearance of 1p/19q losses: case report.

PubMed

Ito, Motokazu; Wakabayashi, Toshihiko; Natsume, Atsushi; Hatano, Hisashi; Fujii, Masazumi; Yoshida, Jun

2007-07-01

Intratumor heterogeneity is of great importance in many clinical aspects of glioma biology, including tumor grading, therapeutic response, and recurrence. Modifications in the genetic features of a specific primary tumor recurring after chemo- and radiotherapy are poorly understood. We report a recurrent glioblastoma case exhibiting loss of heterozygosity (LOH) on chromosome 10q, while the primary tumor exhibited heterogeneity in the LOH status of 1p, 19q, and 10q. To determine the relationship between such modifications and heterogeneous chemosensitivity, primary cultured cells heterogeneously showing 1p/19q/10q losses were established from a surgical specimen of oligoastrocytoma and were treated with chemotherapeutic agents. A 46-year-old woman with a 1-month history of headache and visual disturbances presented to our institution. A right temporoparietal craniotomy and gross total resection were performed. The pathological diagnosis was glioblastoma multiforme with oligodendroglial components. Whereas LOH on 10q was identified at all tumor sites, only the oligodendroglial components exhibited LOH on 1p and 19q. The tumor recurred 6 months after postoperative chemotherapy using interferon-beta and ranimustine, as well as a course of fractionated external-beam radiotherapy (total dose, 60 Gy). Gene analysis revealed no 1p/19q allelic losses but only 10q LOH. Intratumor heterogeneity might be explained by the presence of more than one subclone in the primary tumor. Here, the tumor cells exhibiting 1p/19q LOH with high chemosensitivity might have been killed by the adjuvant therapy and those exhibiting 10q LOH with chemoresistance recurred. This study and our preliminary laboratory findings might suggest an approach to brain tumor physiology, diagnosis, and therapy.

Automated processing of label-free Raman microscope images of macrophage cells with standardized regression for high-throughput analysis.

PubMed

Milewski, Robert J; Kumagai, Yutaro; Fujita, Katsumasa; Standley, Daron M; Smith, Nicholas I

2010-11-19

Macrophages represent the front lines of our immune system; they recognize and engulf pathogens or foreign particles thus initiating the immune response. Imaging macrophages presents unique challenges, as most optical techniques require labeling or staining of the cellular compartments in order to resolve organelles, and such stains or labels have the potential to perturb the cell, particularly in cases where incomplete information exists regarding the precise cellular reaction under observation. Label-free imaging techniques such as Raman microscopy are thus valuable tools for studying the transformations that occur in immune cells upon activation, both on the molecular and organelle levels. Due to extremely low signal levels, however, Raman microscopy requires sophisticated image processing techniques for noise reduction and signal extraction. To date, efficient, automated algorithms for resolving sub-cellular features in noisy, multi-dimensional image sets have not been explored extensively. We show that hybrid z-score normalization and standard regression (Z-LSR) can highlight the spectral differences within the cell and provide image contrast dependent on spectral content. In contrast to typical Raman imaging processing methods using multivariate analysis, such as single value decomposition (SVD), our implementation of the Z-LSR method can operate nearly in real-time. In spite of its computational simplicity, Z-LSR can automatically remove background and bias in the signal, improve the resolution of spatially distributed spectral differences and enable sub-cellular features to be resolved in Raman microscopy images of mouse macrophage cells. Significantly, the Z-LSR processed images automatically exhibited subcellular architectures whereas SVD, in general, requires human assistance in selecting the components of interest. The computational efficiency of Z-LSR enables automated resolution of sub-cellular features in large Raman microscopy data sets without compromise in image quality or information loss in associated spectra. These results motivate further use of label free microscopy techniques in real-time imaging of live immune cells.

Functional relevance of intestinal epithelial cells in inflammatory bowel disease.

PubMed

Okamoto, Ryuichi; Watanabe, Mamoru

2016-01-01

The intestinal epithelium constitutes a physical barrier between inner and outer side of our body. It also functions as a "hub" which connects factors that determine the development of inflammatory bowel disease, such as microbiota, susceptibility genes, and host immune response. Accordingly, recent studies have implicated and further featured the role of intestinal epithelial cell dysfunction in the pathophysiology of inflammatory bowel disease. For example, mucin producing goblet cells are usually "depleted" in ulcerative colitis patients. Studies have shown that those goblet cells exhibit various immune-regulatory functions in addition to mucin production, such as antigen presentation or cytokine production. Paneth cells are another key cell lineage that has been deeply implicated in the pathophysiology of Crohn's disease. Several susceptibility genes for Crohn's disease may lead to impairment of anti-bacterial peptide production and secretion by Paneth cells. Also, other susceptibility genes may determine the survival of Paneth cells, which leads to reduced Paneth cell function in the patient small intestinal mucosa. Further studies may reveal other unexpected roles of the intestinal epithelium in the pathophysiology of inflammatory bowel disease, and may help to develop alternative therapies targeted to intestinal epithelial cell functions.

In Vitro Antiproliferative Effect of the Acetone Extract of Rubus fairholmianus Gard. Root on Human Colorectal Cancer Cells

PubMed Central

Plackal Adimuriyil George, Blassan; Tynga, Ivan Mfouo

2015-01-01

Plants and plant derived products exert chemopreventive effects on various cancer cell lines by the induction of cell death mechanisms. The effects of root acetone extract of Rubus fairholmianus (RFRA) on the proliferation of human colorectal cancer (Caco-2) cells have been investigated in this study. The extract led to a dose dependent decrease in both viability and proliferation and increased cytotoxicity using trypan blue exclusion, adenosine 5′-triphosphate (ATP), and lactate dehydrogenase (LDH) assay. The morphological features of the treated cells were supportive for the antiproliferative activity. The Annexin V/propidium iodide staining indicated that R. fairholmianus induced toxic effects in Caco-2 cells and the percentages of the early and late apoptotic population significantly increased when compared with control cells. Also we studied the apoptosis inducing ability of the extract by analysing caspase 3/7 activity and the induction of cell death via the effector caspases was confirmed; the activity increased in treated cells compared with control. Thus the present findings highlight that the R. fairholmianus root acetone extract exhibits antiproliferative activity on Caco-2 cells by the induction of apoptosis via caspase dependent pathway. PMID:26078938

Dynamic phase differences based on quantitative phase imaging for the objective evaluation of cell behavior.

PubMed

Krizova, Aneta; Collakova, Jana; Dostal, Zbynek; Kvasnica, Lukas; Uhlirova, Hana; Zikmund, Tomas; Vesely, Pavel; Chmelik, Radim

2015-01-01

Quantitative phase imaging (QPI) brought innovation to noninvasive observation of live cell dynamics seen as cell behavior. Unlike the Zernike phase contrast or differential interference contrast, QPI provides quantitative information about cell dry mass distribution. We used such data for objective evaluation of live cell behavioral dynamics by the advanced method of dynamic phase differences (DPDs). The DPDs method is considered a rational instrument offered by QPI. By subtracting the antecedent from the subsequent image in a time-lapse series, only the changes in mass distribution in the cell are detected. The result is either visualized as a two dimensional color-coded projection of these two states of the cell or as a time dependence of changes quantified in picograms. Then in a series of time-lapse recordings, the chain of cell mass distribution changes that would otherwise escape attention is revealed. Consequently, new salient features of live cell behavior should emerge. Construction of the DPDs method and results exhibiting the approach are presented. Advantage of the DPDs application is demonstrated on cells exposed to an osmotic challenge. For time-lapse acquisition of quantitative phase images, the recently developed coherence-controlled holographic microscope was employed.

Dynamic phase differences based on quantitative phase imaging for the objective evaluation of cell behavior

NASA Astrophysics Data System (ADS)

Krizova, Aneta; Collakova, Jana; Dostal, Zbynek; Kvasnica, Lukas; Uhlirova, Hana; Zikmund, Tomas; Vesely, Pavel; Chmelik, Radim

2015-11-01

Quantitative phase imaging (QPI) brought innovation to noninvasive observation of live cell dynamics seen as cell behavior. Unlike the Zernike phase contrast or differential interference contrast, QPI provides quantitative information about cell dry mass distribution. We used such data for objective evaluation of live cell behavioral dynamics by the advanced method of dynamic phase differences (DPDs). The DPDs method is considered a rational instrument offered by QPI. By subtracting the antecedent from the subsequent image in a time-lapse series, only the changes in mass distribution in the cell are detected. The result is either visualized as a two-dimensional color-coded projection of these two states of the cell or as a time dependence of changes quantified in picograms. Then in a series of time-lapse recordings, the chain of cell mass distribution changes that would otherwise escape attention is revealed. Consequently, new salient features of live cell behavior should emerge. Construction of the DPDs method and results exhibiting the approach are presented. Advantage of the DPDs application is demonstrated on cells exposed to an osmotic challenge. For time-lapse acquisition of quantitative phase images, the recently developed coherence-controlled holographic microscope was employed.

A pyrene-benzthiazolium conjugate portraying aggregation induced emission, a ratiometric detection and live cell visualization of HSO3(.).

PubMed

Diwan, Uzra; Kumar, Virendra; Mishra, Rakesh K; Rana, Nishant Kumar; Koch, Biplob; Singh, Manish Kumar; Upadhyay, K K

2016-07-27

The present study deals with the photophysical property of a pyrene-benzthiazolium conjugate R1, as a strong intramolecular charge transfer (ICT) probe exhibiting long wavelength emission in the red region. Unlike traditional planar polyaromatic hydrocarbons whose aggregation generally quenches the light emission, the pyrene based R1 was found to display aggregation-induced emission (AIE) property along with simultaneous increase in its quantum yield upon increasing the water content of the medium. The R1 exhibits high specificity towards HSO3(-)/SO3(2-) by interrupting its own ICT producing there upon a large ratiometric blue shift of ∼220 nm in its emission spectrum. The lowest detection limit for the above measurement was found to be 8.90 × 10(-8) M. The fluorescent detection of HSO3(-) was also demonstrated excellently by test paper strip and silica coated TLC plate incorporating R1. The live cell imaging of HSO3(─) through R1 in HeLa cells was studied using fluorescence microscopic studies. The particle size and morphological features of R1 and R1-HSO3(-) aggregates in aqueous solution were characterized by DLS along with SEM analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Cobalt nanoparticles for biomedical applications: Facile synthesis, physiochemical characterization, cytotoxicity behavior and biocompatibility

NASA Astrophysics Data System (ADS)

Ansari, S. M.; Bhor, R. D.; Pai, K. R.; Sen, D.; Mazumder, S.; Ghosh, Kartik; Kolekar, Y. D.; Ramana, C. V.

2017-08-01

Cobalt (Co) nanoparticles (NPs) were produced by a simple, one step hydrothermal method with the capping of oleic acid. Intrinsic structural, physiochemical and magnetic properties of Co NPs were investigated and demonstrated their applicability in biomedicine. X-ray diffraction, Raman spectroscopy and infrared (IR) spectroscopic studies confirm the single phase Co NPs with a high structural quality. The IR data revealed the capping of oleic acid via monodentate interaction. Small angle scattering studies suggest the existence of sticky hard sphere type of interaction among the Co NPs because of magnetic interaction which is further evidenced by electron microscopy imaging analyses. The Co NPs exhibit a ferromagnetic character over a wide range of temperature (20-300 K). The temperature dependence of magnetic parameters namely, saturation magnetization, remanent magnetization, coercivity and reduced remanent magnetization were determined and correlated with structure of Co NPs. The Cytotoxicity studies demonstrate that these Co NPs exhibit the mild anti-proliferative character against the cancer cells (cisplatin resistant ovarian cancer (A2780/CP70)) and safe nature towards the normal cells. Haemolytic behavior of human red blood cells (RBC) revealed (<5%) haemolysis signifying the compatibility of Co NPs with human RBC which is an essential feature in vivo biomedical applications without creating any harmful effects in the human blood stream.

Fabrication of hierarchical micro-nanotopographies for cell attachment studies.

PubMed

López-Bosque, M J; Tejeda-Montes, E; Cazorla, M; Linacero, J; Atienza, Y; Smith, K H; Lladó, A; Colombelli, J; Engel, E; Mata, A

2013-06-28

We report on the development of micro/nanofabrication processes to create hierarchical surface topographies that expand from 50 nm to microns in size on different materials. Three different approaches (named FIB1, FIB2, and EBL) that combine a variety of techniques such as photolithography, reactive ion etching, focused ion beam lithography, electron beam lithography, and soft lithography were developed, each one providing different advantages and disadvantages. The EBL approach was employed to fabricate substrates comprising channels with features between 200 nm and 10 μm in size on polymethylmethacrylate (PMMA), which were then used to investigate the independent or competitive effects of micro- and nanotopographies on cell adhesion and morphology. Rat mesenchymal stem cells (rMSCs) were cultured on four different substrates including 10 μm wide and 500 nm deep channels separated by 10 μm distances (MICRO), 200 nm wide and 100 nm deep nanochannels separated by 200 nm distances (NANO), their combination in parallel (PARAL), and in a perpendicular direction (PERP). Rat MSCs behaved differently on all tested substrates with a high degree of alignment (as measured by both number of aligned cells and average angle) on both NANO and MICRO. Furthermore, cells exhibited the highest level of alignment on PARAL, suggesting a synergetic effect of the two scales of topographies. On the other hand, cells on PERP exhibited the lowest alignment and a consistent change in morphology over time that seemed to be the result of interactions with both micro- and nanochannels positioned in the perpendicular direction, also suggesting a competitive effect of the topographies.

Tumor-initiating cells of breast and prostate origin show alterations in the expression of genes related to iron metabolism

PubMed Central

Tomkova, Veronika; Korenkova, Vlasta; Langerova, Lucie; Simonova, Ekaterina; Zjablovskaja, Polina; Alberich-Jorda, Meritxell; Neuzil, Jiri; Truksa, Jaroslav

2017-01-01

The importance of iron in the growth and progression of tumors has been widely documented. In this report, we show that tumor-initiating cells (TICs), represented by spheres derived from the MCF7 cell line, exhibit higher intracellular labile iron pool, mitochondrial iron accumulation and are more susceptible to iron chelation. TICs also show activation of the IRP/IRE system, leading to higher iron uptake and decrease in iron storage, suggesting that level of properly assembled cytosolic iron-sulfur clusters (FeS) is reduced. This finding is confirmed by lower enzymatic activity of aconitase and FeS cluster biogenesis enzymes, as well as lower levels of reduced glutathione, implying reduced FeS clusters synthesis/utilization in TICs. Importantly, we have identified specific gene signature related to iron metabolism consisting of genes regulating iron uptake, mitochondrial FeS cluster biogenesis and hypoxic response (ABCB10, ACO1, CYBRD1, EPAS1, GLRX5, HEPH, HFE, IREB2, QSOX1 and TFRC). Principal component analysis based on this signature is able to distinguish TICs from cancer cells in vitro and also Leukemia-initiating cells (LICs) from non-LICs in the mouse model of acute promyelocytic leukemia (APL). Majority of the described changes were also recapitulated in an alternative model represented by MCF7 cells resistant to tamoxifen (TAMR) that exhibit features of TICs. Our findings point to the critical importance of redox balance and iron metabolism-related genes and proteins in the context of cancer and TICs that could be potentially used for cancer diagnostics or therapy. PMID:28031527

Emerging insights into recurrent and metastatic human papillomavirus‐related oropharyngeal squamous cell carcinoma

PubMed Central

Faraji, Farhoud; Eisele, David W.

2017-01-01

ABSTRACT Objective To review recent literature on human papillomavirus‐related (HPV‐positive) oropharyngeal squamous cell carcinoma (OPC) and focus on implications of recurrent and metastatic disease. Methods Primary articles from 1990 to 2016 indexed in MEDLINE (1) pertaining to the epidemiology of HPV‐positive OPC and (2) providing clinical insight into recurrent and metastatic OPC. Results The incidence of HPV‐positive OPC is increasing globally. HPV‐positive OPC is a subtype with distinct molecular and clinical features including enhanced treatment response and improved overall survival. While disease recurrence is less common in patients with HPV‐positive OPC, up to 36% of patients experience treatment failure within eight years. Recurrent and metastatic OPC has historically signified poor prognosis, however recent data are challenging this dogma. Here, we discuss recurrent and metastatic OPC in the context of HPV tumor status. Conclusion HPV‐positive OPC exhibits distinct genetic, cellular, epidemiological, and clinical features from HPV‐negative OPC. HPV tumor status is emerging as a marker indicative of improved prognosis after disease progression in both locoregionally recurrent and distant metastatic OPC. Level of Evidence N/A. PMID:28894817

Multi-color flow cytometry for evaluating age-related changes in memory lymphocyte subsets in dogs.

PubMed

Withers, Sita S; Moore, Peter F; Chang, Hong; Choi, Jin W; McSorley, Stephen J; Kent, Michael S; Monjazeb, Arta M; Canter, Robert J; Murphy, William J; Sparger, Ellen E; Rebhun, Robert B

2018-05-31

While dogs are increasingly being utilized as large-animal models of disease, important features of age-related immunosenescence in the dog have yet to be evaluated due to the lack of defined naïve vs. memory T lymphocyte phenotypes. We therefore performed multi-color flow cytometry on peripheral blood mononuclear cells from young and aged beagles, and determined the differential cytokine production by proposed memory subsets. CD4+ and CD8+ T lymphocytes in aged dogs displayed increased cytokine production, and decreased proliferative capacity. Antibodies targeting CD45RA and CD62L, but less so CD28 or CD44, defined canine cells that consistently exhibited properties of naïve-, central memory-, effector memory-, and terminal effector-like CD4+ and CD8+ T lymphocyte subsets. Older dogs demonstrated decreased frequencies of naïve-like CD4+ and CD8+ T lymphocytes, and an increased frequency of terminal effector-like CD8+ T lymphocytes. Overall findings revealed that aged dogs displayed features of immunosenescence similar to those reported in other species. Copyright © 2018 Elsevier Ltd. All rights reserved.

Mutation of NLRC4 causes a syndrome of enterocolitis and autoinflammation

PubMed Central

Nelson-Williams, Carol; Stiegler, Amy L; Loring, Erin; Choi, Murim; Overton, John; Meffre, Eric; Khokha, Mustafa K; Huttner, Anita J; West, Brian; Podoltsev, Nikolai A; Boggon, Titus J; Kazmierczak, Barbara I; Lifton, Richard P

2014-01-01

Upon detection of pathogen-associated molecular patterns, innate immune receptors initiate inflammatory responses. These receptors include cytoplasmic NOD-like receptors (NLRs), whose stimulation recruits and proteolytically activates caspase-1 within the inflammasome, a multi-protein complex. Caspase-1 mediates the production of interleukin-1 family cytokines (IL1FCs), leading to fever, and inflammatory cell death (pyroptosis)1,2. Mutations that constitutively activate these pathways underlie several autoinflammatory diseases with diverse clinical features3. We describe a family with a previously unreported syndrome featuring neonatal-onset enterocolitis, periodic fever, and fatal/near-fatal episodes of autoinflammation caused by a de novo gain-of-function mutation (p.V341A) in the HD1 domain of NLRC4 that co-segregates with disease. Mutant NLRC4 causes constitutive Interleukin-1 family cytokine production and macrophage cell death. Infected patient macrophages are polarized toward pyroptosis and exhibit abnormal staining for inflammasome components. These findings describe and reveal the cause of a life-threatening but treatable autoinflammatory disease that underscores the divergent roles of the NLRC4 inflammasome. PMID:25217960

Activating PIK3CD mutations impair human cytotoxic lymphocyte differentiation, function and EBV immunity.

PubMed

Edwards, Emily S J; Bier, Julia; Cole, Theresa S; Wong, Melanie; Hsu, Peter; Berglund, Lucinda J; Boztug, Kaan; Lau, Anthony; Gostick, Emma; Price, David A; O'Sullivan, Michael; Meyts, Isabelle; Choo, Sharon; Gray, Paul; Holland, Steven M; Deenick, Elissa K; Uzel, Gulbu; Tangye, Stuart G

2018-05-22

Germline gain-of function (GOF) mutations in PIK3CD, encoding the catalytic p110δ subunit of phosphatidylinositol-3 kinase, result in hyperactivation of the PI3K-AKT-mTOR pathway and underlie a novel inborn error of immunity. Affected individuals exhibit perturbed humoral and cellular immunity, manifesting as recurrent infections, autoimmunity, hepatosplenomegaly, uncontrolled EBV and/or CMV infection, and an increased incidence of B-cell lymphoproliferation and/or lymphoma. Mechanisms underlying disease pathogenesis remain unknown. Understanding the cellular and molecular mechanisms underpinning inefficient surveillance of EBV-infected B cells is required to understand disease in individuals with PIK3CD GOF mutations, identify key molecules required for cell mediated immunity against EBV, and develop immunotherapeutic interventions for the treatment of this as well as other EBV-opathies. We studied the consequences of PIK3CD GOF mutations on the generation, differentiation and function of CD8 + T cells and NK cells, which are implicated in host defense against infection with herpesviruses including EBV. PIK3CD GOF total and EBV-specific CD8 + T cells were skewed towards an effector phenotype, with exaggerated expression of markers associated with premature immunosenescence/exhaustion, and increased susceptibility to re-activation induced cell death. These findings were recapitulated in a novel mouse model of PI3K GOF. NK cells in PIK3CD GOF individuals also exhibited perturbed expression of differentiation-associated molecules. Both CD8 + T cells and NK cells had reduced capacity to kill EBV-infected B cells. PIK3CD GOF B cells had increased expression of CD48, PDL-1/2 and CD70. PIK3CD GOF mutations aberrantly induce exhaustion and/or senescence and impair cytotoxicity of CD8+ T and NK cells. These defects may contribute to clinical features of affected individuals, such as impaired immunity to herpesviruses and tumor surveillance. Copyright © 2018. Published by Elsevier Inc.

Differentiation-associated alteration in human monocyte-macrophage accessory cell function.

PubMed

Mayernik, D G; Ul-Haq, A; Rinehart, J J

1983-05-01

Human monocyte (Mo) to macrophage (Mx) differentiation is associated with marked and well studied changes in morphology, biochemical parameters, and effector cell function. Nevertheless, the comparative accessory cell (AC) function of blood Mo and differentiated Mx has not been carefully studied. We, therefore, examined the kinetics and mechanisms of change in AC function during in vitro Mo to Mx differentiation. The system utilized has two distinctive features: blood Mo and resultant cultured Mx represent a cohort of cells derived from the bone marrow within a 12-hr period. Moreover, the in vitro derived Mx utilized herein have been characterized extensively and are functionally and biochemically similar to pulmonary macrophages (PMx). In the experiments reported, AC functions of blood Mo, Mx derived from Mo after 1 to 6 days of culture, and PMx was compared. AC were cultured with nylon wool column-purified autologous T cells and were stimulated with concanavalin A (Con A) or streptokinase-streptodornase (SKSD). Blood T cell proliferation to Con A or SKSD was inhibited greater than 90% by the removal of Mo and was reconstituted by 20% Mo. Mx derived from Mo by culture for 1 to 3 days exhibited the same (or better) AC function as Mo when T cells were stimulated with either SKSD or Con A. In marked contrast, Mx derived from 6-day cultures exhibited less than or equal to 15% of Mo (i.e., control) capacity to support T cell proliferative response to SKSD. Six-day Mx support T cell proliferation to Con A was somewhat variable. Similar to 6-day cultured Mx, PMx failed to function as AC. The mechanism of loss of AC function was examined: a) cultured Mx maintained Ia antigen positivity for greater than 8 days; b) mixing experiments with Mo + 6-day cultured Mx or Mo + PMx demonstrated no T cell suppression; c) the normal capacity of most 6-day cultured Mx to support Con A but not SKSD induced T cell proliferation, apparently ruled out the loss of the ability to deliver a nonspecific "second signal" as the involved mechanism; d) inhibition of Mo to Mx differentiation by dexamethasone preserved AC activity. Thus, human culture-derived Mx and PMx exhibit deficit AC function through loss of an undefined mechanism. However, loss of AC antigen processing or presentation may occur.

Osteoinductive peptide-functionalized nanofibers with highly ordered structure as biomimetic scaffolds for bone tissue engineering.

PubMed

Gao, Xiang; Zhang, Xiaohong; Song, Jinlin; Xu, Xiao; Xu, Anxiu; Wang, Mengke; Xie, Bingwu; Huang, Enyi; Deng, Feng; Wei, Shicheng

2015-01-01

The construction of functional biomimetic scaffolds that recapitulate the topographical and biochemical features of bone tissue extracellular matrix is now of topical interest in bone tissue engineering. In this study, a novel surface-functionalized electrospun polycaprolactone (PCL) nanofiber scaffold with highly ordered structure was developed to simulate the critical features of native bone tissue via a single step of catechol chemistry. Specially, under slightly alkaline aqueous solution, polydopamine (pDA) was coated on the surface of aligned PCL nanofibers after electrospinning, followed by covalent immobilization of bone morphogenetic protein-7-derived peptides onto the pDA-coated nanofiber surface. Contact angle measurement, Raman spectroscopy, and X-ray photoelectron spectroscopy confirmed the presence of pDA and peptides on PCL nanofiber surface. Our results demonstrated that surface modification with osteoinductive peptides could improve cytocompatibility of nanofibers in terms of cell adhesion, spreading, and proliferation. Most importantly, Alizarin Red S staining, quantitative real-time polymerase chain reaction, immunostaining, and Western blot revealed that human mesenchymal stem cells cultured on aligned nanofibers with osteoinductive peptides exhibited enhanced osteogenic differentiation potential than cells on randomly oriented nanofibers. Furthermore, the aligned nanofibers with osteoinductive peptides could direct osteogenic differentiation of human mesenchymal stem cells even in the absence of osteoinducting factors, suggesting superior osteogenic efficacy of biomimetic design that combines the advantages of osteoinductive peptide signal and highly ordered nanofibers on cell fate decision. The presented peptide-decorated bone-mimic nanofiber scaffolds hold a promising potential in the context of bone tissue engineering.

A two parameter family of travelling waves with a singular barrier arising from the modelling of extracellular matrix mediated cellular invasion

NASA Astrophysics Data System (ADS)

Perumpanani, Abbey J.; Sherratt, Jonathan A.; Norbury, John; Byrne, Helen M.

1999-02-01

Invasive cells variously show changes in adhesion, protease production and motility. In this paper the authors develop and analyse a model for malignant invasion, brought about by a combination of proteolysis and haptotaxis. A common feature of these two mechanisms is that they can be produced by contact with the extracellular matrix through the mediation of a class of surface receptors called integrins. An unusual feature of the model is the absence of cell diffusion. By seeking travelling wave solutions the model is reduced to a system of ordinary differential equations which can be studied using phase plane analysis. The authors demonstrate the presence of a singular barrier in the phase plane and a “hole” in this singular barrier which admits a phase trajectory. The model admits a family of travelling waves which depend on two parameters, i.e. the tissue concentration of connective tissue and the rate of decay of the initial spatial profile of the invading cells. The slowest member of this family corresponds to the phase trajectory which goes through the “hole” in the singular barrier. Using a power series method the authors derive an expression relating the minimum wavespeed to the tissue concentration of the extracellular matrix which is arbitrary. The model is applicable in a wide variety of biological settings which combine haptotaxis with proteolysis. By considering various functional forms the authors show that the key mathematical features of the particular model studied in the early parts of the paper are exhibited by a wider class of models which characterise the behaviour of invading cells.

Eosinophilia in primary biliary cirrhosis.

PubMed

Yamazaki, K; Nakadate, I; Suzuki, K; Sato, S; Masuda, T

1996-03-01

Recent studies have shown the occurrence of eosinophilia in patients with primary biliary cirrhosis (PBC). To examine whether eosinophilia is indeed a distinctive feature of PBC, we performed extensive leukocyte differential analysis using a highly sophisticated hematology instrument. We also investigated the relationship between eosinophil dynamics and clinical features of PBC including the effects of ursodeoxycholic acid (UDCA) treatment. A flow cytometry-based blood cell analyzer (Technicon H6000) was used to examine peripheral blood eosinophil counts in 38 patients with PBC and 131 patients with various liver deseases. We also performed eosinophil quantitation in 19 PBC patients before and after administration of UDCA for 4 wk. Patients with PBC had significantly higher relative and absolute eosinophil counts when compared with other liver diseases (5.7 +/- 0.5% [p < 0.0001, mean +/- SEM] and 312 +/- 26 cells/microliter [p < 0.01], respectively). Twenty-one of 38 PBC patients (55%) exhibited relative eosinophilia. In patients with PBC, the eosinophil count was: 1) significantly higher in those with early histological stages (stage I-II, 6.5 +/- 0.5% vs stage III-IV, 4.4 +/- 0.7%,p < 0.05), 2) positively correlated with basophil count (p < 0.01), serum IgA levels (p < 0.05), and the degree of eosinophil infiltration in the portal tract (p < 0.01), and 3) markedly reduced by UDCA treatment (before: 5.9 +/- 0.7%, 307 +/- 37 cells/microliter; after: 2.8 +/- 0.03% [p < 0.001], 162 +/- 26 cells/microliter ¿p < 0.001]). Eosinophilia is a common and distinctive feature of patients with PBC. UDCA ameliorates eosinophilia as well as liver function tests in PBC patients. Eosinophilia may be useful as one of the initial clues in the diagnosis of PBC, especially in its early stage.

Protective Effect of Coriolus versicolor Cultivated in Citrus Extract Against Nitric Oxide-Induced Apoptosis in Human Neuroblastoma SK-N-MC Cells

PubMed Central

Kim, Byung-Chul; Kim, Youn-Sub; Lee, Jin-Woo; Seo, Jin-Hee; Ji, Eun-Sang; Lee, Hyejung; Park, Yong-Il

2011-01-01

Nitric oxide (NO) is a reactive free radical and a messenger molecule in many physiological functions. However, excessive NO is believed to be a mediator of neurotoxicity. The medicinal plant Coriolus versicolor is known to possess anti-tumor and immune-potentiating activities. In this study, we investigated whether Coriolus versicolor possesses a protective effect against NO donor sodium nitroprusside (SNP)-induced apoptosis in the human neuroblastoma cell line SK-N-MC. We utilized 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, 4,6-diamidino-2-phenylindole (DAPI) staining, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, DNA fragmentation assay, reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis, and caspase-3 enzyme activity assay in SK-N-MC cells. MTT assay showed that SNP treatment significantly reduces the viability of cells, and the viabilities of cells pre-treated with the aqueous extract of Coriolus versicolor cultivated in citrus extract (CVEcitrus) was increased. However, aqueous extract of Coriolus versicolor cultivated in synthetic medium (CVEsynthetic) showed no protective effect and aqueous citrus extract (CE) had a little protective effect. The cell treated with SNP exhibited several apoptotic features, while those pre-treated for 1 h with CVEcitrus prior to SNP expose showed reduced apoptotic features. The cells pre-treated for 1 h with CVEcitrus prior to SNP expose inhibited p53 and Bax expressions and caspase-3 enzyme activity up-regulated by SNP. We showed that CVEcitrus exerts a protective effect against SNP-induced apoptosis in SK-N-MC cells. Our study suggests that CVEcitrus has therapeutic value in the treatment of a variety of NO-induced brain diseases. PMID:22110367

Protective Effect of Coriolus versicolor Cultivated in Citrus Extract Against Nitric Oxide-Induced Apoptosis in Human Neuroblastoma SK-N-MC Cells.

PubMed

Kim, Byung-Chul; Kim, Youn-Sub; Lee, Jin-Woo; Seo, Jin-Hee; Ji, Eun-Sang; Lee, Hyejung; Park, Yong-Il; Kim, Chang-Ju

2011-06-01

Nitric oxide (NO) is a reactive free radical and a messenger molecule in many physiological functions. However, excessive NO is believed to be a mediator of neurotoxicity. The medicinal plant Coriolus versicolor is known to possess anti-tumor and immune-potentiating activities. In this study, we investigated whether Coriolus versicolor possesses a protective effect against NO donor sodium nitroprusside (SNP)-induced apoptosis in the human neuroblastoma cell line SK-N-MC. We utilized 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, 4,6-diamidino-2-phenylindole (DAPI) staining, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, DNA fragmentation assay, reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis, and caspase-3 enzyme activity assay in SK-N-MC cells. MTT assay showed that SNP treatment significantly reduces the viability of cells, and the viabilities of cells pre-treated with the aqueous extract of Coriolus versicolor cultivated in citrus extract (CVE(citrus)) was increased. However, aqueous extract of Coriolus versicolor cultivated in synthetic medium (CVE(synthetic)) showed no protective effect and aqueous citrus extract (CE) had a little protective effect. The cell treated with SNP exhibited several apoptotic features, while those pre-treated for 1 h with CVE(citrus) prior to SNP expose showed reduced apoptotic features. The cells pre-treated for 1 h with CVE(citrus) prior to SNP expose inhibited p53 and Bax expressions and caspase-3 enzyme activity up-regulated by SNP. We showed that CVE(citrus) exerts a protective effect against SNP-induced apoptosis in SK-N-MC cells. Our study suggests that CVE(citrus) has therapeutic value in the treatment of a variety of NO-induced brain diseases.

Advances in ethanol production using immobilized cell systems

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

Margaritis, A.; Merchant, F.J.A.

The application of immobilized cell systems for the production of ethanol has resulted in substantial improvements in the efficiency of the process when compared to the traditional free cell system. In this review, the various methods of cell immobilization employed in ethanol production systems have been described in detail. Their salient features, performance characteristics, advantages and limitations have been critically assessed. More recently, these immobilized cell systems have also been employed for the production of ethanol from non-conventional feedstocks such as Jerusalem artichoke extracts, cheese whey, cellulose, cellobiose and xylose. Ethanol production by immobilized yeast and bacterial cells has beenmore » attempted in various bioreactor types. Although most of these studies have been carried out using laboratory scale prototype bioreactors, it appears that only fluidized bed, horizontally packed bed bioreactors and tower fermenters may find application on scale-up. Several studies have indicated that upon immobilization, yeast cells performing ethanol fermentation exhibit more favourable physiological and metabolic properties. This, in addition to substantial improvements in ethanol productivities by immobilized cell systems, is indicative of the fact that future developments in the production of ethanol and alcoholic beverages will be directed towards the use of immobilized cell systems. 291 references.« less

A review on the chemotherapeutic potential of fisetin: In vitro evidences.

PubMed

Sundarraj, Kiruthika; Raghunath, Azhwar; Perumal, Ekambaram

2018-01-01

During the past five decades, cancer cell lines are being successfully used as an in vitro model to discover the anti-cancer potential of plant secondary metabolites. Fisetin - the most popular polyphenol from fruits and vegetables, exhibits a repertoire of promising pharmacological features. Such versatile properties make fisetin an excellent anticancer agent and its efficacy as a chemotherapeutic agent against tumor heterogeneity from in vitro studies are encouraging. Fisetin is like a Pandora's box, as more research studies are being carried out, it reveals its new molecules within the cancer cells as therapeutic targets. These molecular targets orchestrate processes such as apoptosis, autophagic cell death, cell cycle, invasion, metastasis and angiogenesis in cancer cells. Besides apoptotic elicitation, fisetin's ability to induce autophagic cell death in cancer cells has been reported. This review examines the various molecular mechanisms of action elicited by fisetin leading to apoptosis and autophagic cell death as evidenced from cancer cell lines. In addition, the increased bioavailability and sustained release of fisetin improved through conjugation and enhanced effect of fisetin through synergism on various cancers are also highlighted. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Proflavine Hemisulfate as a Fluorescent Contrast Agent for Point-of-Care Cytology

PubMed Central

Prieto, Sandra P.; Powless, Amy J.; Boice, Jackson W.; Sharma, Shree G.; Muldoon, Timothy J.

2015-01-01

Proflavine hemisulfate, an acridine-derived fluorescent dye, can be used as a rapid stain for cytologic examination of biological specimens. Proflavine fluorescently stains cell nuclei and cytoplasmic structures, owing to its small amphipathic structure and ability to intercalate DNA. In this manuscript, we demonstrated the use of proflavine as a rapid cytologic dye on a number of specimens, including normal exfoliated oral squamous cells, cultured human oral squamous carcinoma cells, and leukocytes derived from whole blood specimens using a custom-built, portable, LED-illuminated fluorescence microscope. No incubation time was needed after suspending cells in 0.01% (w/v) proflavine diluted in saline. Images of proflavine stained oral cells had clearly visible nuclei as well as granular cytoplasm, while stained leukocytes exhibited bright nuclei, and highlighted the multilobar nature of nuclei in neutrophils. We also demonstrated the utility of quantitative analysis of digital images of proflavine stained cells, which can be used to detect significant morphological differences between different cell types. Proflavine stained oral cells have well-defined nuclei and cell membranes which allowed for quantitative analysis of nuclear to cytoplasmic ratios, as well as image texture analysis to extract quantitative image features. PMID:25962131

Proflavine Hemisulfate as a Fluorescent Contrast Agent for Point-of-Care Cytology.

PubMed

Prieto, Sandra P; Powless, Amy J; Boice, Jackson W; Sharma, Shree G; Muldoon, Timothy J

2015-01-01

Proflavine hemisulfate, an acridine-derived fluorescent dye, can be used as a rapid stain for cytologic examination of biological specimens. Proflavine fluorescently stains cell nuclei and cytoplasmic structures, owing to its small amphipathic structure and ability to intercalate DNA. In this manuscript, we demonstrated the use of proflavine as a rapid cytologic dye on a number of specimens, including normal exfoliated oral squamous cells, cultured human oral squamous carcinoma cells, and leukocytes derived from whole blood specimens using a custom-built, portable, LED-illuminated fluorescence microscope. No incubation time was needed after suspending cells in 0.01% (w/v) proflavine diluted in saline. Images of proflavine stained oral cells had clearly visible nuclei as well as granular cytoplasm, while stained leukocytes exhibited bright nuclei, and highlighted the multilobar nature of nuclei in neutrophils. We also demonstrated the utility of quantitative analysis of digital images of proflavine stained cells, which can be used to detect significant morphological differences between different cell types. Proflavine stained oral cells have well-defined nuclei and cell membranes which allowed for quantitative analysis of nuclear to cytoplasmic ratios, as well as image texture analysis to extract quantitative image features.

Novel 20(S)-sulfonylamidine derivatives of camptothecin and the use thereof as a potent antitumor agent: a patent evaluation of WO2015048365 (A1).

PubMed

Beretta, Giovanni Luca; Zaffaroni, Nadia; Varchi, Greta

2016-05-01

A series of camptothecin (CPT) derivatives featuring acyl-esterification of the 20(S)-hydroxyl group with a residue containing a sulfonylamidine moiety is synthesized via a Cu catalyzed three-component reaction. The compounds show remarkable cytotoxicity against a panel of tumor cells, including a cell line exhibiting Multi-Drug Resistant (MDR) phenotype. The patent develops 9a, the best derivative of the series, that i) selectively poisons DNA Topoisomerase I (TopoI); ii) induces cell-cycle S-phase arrest with activation of the DNA damage response pathway and apoptosis induction and iii) shows considerable in vivo antitumor potency. We envision that the peculiar modification of the 20(S)-hydroxyl group of CPT with a sulfonylamidine residue will play a continuing role in affording new TopoI poison drug candidates for therapeutic applications.

Quorum Sensing Gene Regulation by LuxR/HapR Master Regulators in Vibrios

PubMed Central

Ball, Alyssa S.; Chaparian, Ryan R.

2017-01-01

ABSTRACT The coordination of group behaviors in bacteria is accomplished via the cell-cell signaling process called quorum sensing. Vibrios have historically been models for studying bacterial communication due to the diverse and remarkable behaviors controlled by quorum sensing in these bacteria, including bioluminescence, type III and type VI secretion, biofilm formation, and motility. Here, we discuss the Vibrio LuxR/HapR family of proteins, the master global transcription factors that direct downstream gene expression in response to changes in cell density. These proteins are structurally similar to TetR transcription factors but exhibit distinct biochemical and genetic features from TetR that determine their regulatory influence on the quorum sensing gene network. We review here the gene groups regulated by LuxR/HapR and quorum sensing and explore the targets that are common and unique among Vibrio species. PMID:28484045

Formation of rarefaction waves in origami-based metamaterials

DOE PAGES

Yasuda, H.; Chong, C.; Charalampidis, E. G.; ...

2016-04-15

Here, we investigate the nonlinear wave dynamics of origami-based metamaterials composed of Tachi-Miura polyhedron (TMP) unit cells. These cells exhibit strain softening behavior under compression, which can be tuned by modifying their geometrical configurations or initial folded conditions. We assemble these TMP cells into a cluster of origami-based metamaterials, and we theoretically model and numerically analyze their wave transmission mechanism under external impact. Numerical simulations show that origami-based metamaterials can provide a prototypical platform for the formation of nonlinear coherent structures in the form of rarefaction waves, which feature a tensile wavefront upon the application of compression to the system.more » We also demonstrate the existence of numerically exact traveling rarefaction waves in an effective lumped-mass model. Origami-based metamaterials can be highly useful for mitigating shock waves, potentially enabling a wide variety of engineering applications.« less

TASI: A software tool for spatial-temporal quantification of tumor spheroid dynamics.

PubMed

Hou, Yue; Konen, Jessica; Brat, Daniel J; Marcus, Adam I; Cooper, Lee A D

2018-05-08

Spheroid cultures derived from explanted cancer specimens are an increasingly utilized resource for studying complex biological processes like tumor cell invasion and metastasis, representing an important bridge between the simplicity and practicality of 2-dimensional monolayer cultures and the complexity and realism of in vivo animal models. Temporal imaging of spheroids can capture the dynamics of cell behaviors and microenvironments, and when combined with quantitative image analysis methods, enables deep interrogation of biological mechanisms. This paper presents a comprehensive open-source software framework for Temporal Analysis of Spheroid Imaging (TASI) that allows investigators to objectively characterize spheroid growth and invasion dynamics. TASI performs spatiotemporal segmentation of spheroid cultures, extraction of features describing spheroid morpho-phenotypes, mathematical modeling of spheroid dynamics, and statistical comparisons of experimental conditions. We demonstrate the utility of this tool in an analysis of non-small cell lung cancer spheroids that exhibit variability in metastatic and proliferative behaviors.

Merkel cell carcinoma: Do you know your guidelines?

PubMed

Miles, Brett A; Goldenberg, David

2016-05-01

Merkel cell carcinoma (MCC) is a cutaneous neuroendocrine malignancy that exhibits clinically aggressive features and is associated with a poor prognosis. The incidence of MCC seems to be increasing for reasons unknown, and is estimated to be 0.32/100,000 in the United States. This article will review the current literature and National Comprehensive Cancer Network practice guidelines in the treatment of MCC. Resection of MCC with negative margins remains the mainstay of therapy. Positive nodal disease should be treated with neck dissection and adjuvant radiotherapy. High-risk patients should undergo adjuvant radiotherapy, which improves oncologic outcomes. The role of chemotherapy is less clear and is currently reserved for advanced-stage MCC and palliative therapy. The pathogenesis of MCC has recently been impacted with the discovery of the Merkel cell polyomavirus (MCPyV). Research to establish targeted and immunologic therapeutic options are ongoing. © 2015 Wiley Periodicals, Inc.

Exploring natural silk protein sericin for regenerative medicine: an injectable, photoluminescent, cell-adhesive 3D hydrogel.

PubMed

Wang, Zheng; Zhang, Yeshun; Zhang, Jinxiang; Huang, Lei; Liu, Jia; Li, Yongkui; Zhang, Guozheng; Kundu, Subhas C; Wang, Lin

2014-11-20

Sericin, a major component of silk, has a long history of being discarded as a waste during silk processing. The value of sericin for tissue engineering is underestimated and its potential application in regenerative medicine has just begun to be explored. Here we report the successful fabrication and characterization of a covalently-crosslinked 3D pure sericin hydrogel for delivery of cells and drugs. This hydrogel is injectable, permitting its implantation through minimally invasive approaches. Notably, this hydrogel is found to exhibit photoluminescence, enabling bioimaging and in vivo tracking. Moreover, this hydrogel system possesses excellent cell-adhesive capability, effectively promoting cell attachment, proliferation and long-term survival of various types of cells. Further, the sericin hydrogel releases bioactive reagents in a sustained manner. Additionally, this hydrogel demonstrates good elasticity, high porosity, and pH-dependent degradation dynamics, which are advantageous for this sericin hydrogel to serve as a delivery vehicle for cells and therapeutic drugs. With all these unique features, it is expected that this sericin hydrogel will have wide utility in the areas of tissue engineering and regenerative medicine.

Exploring natural silk protein sericin for regenerative medicine: an injectable, photoluminescent, cell-adhesive 3D hydrogel

PubMed Central

Wang, Zheng; Zhang, Yeshun; Zhang, Jinxiang; Huang, Lei; Liu, Jia; Li, Yongkui; Zhang, Guozheng; Kundu, Subhas C.; Wang, Lin

2014-01-01

Sericin, a major component of silk, has a long history of being discarded as a waste during silk processing. The value of sericin for tissue engineering is underestimated and its potential application in regenerative medicine has just begun to be explored. Here we report the successful fabrication and characterization of a covalently-crosslinked 3D pure sericin hydrogel for delivery of cells and drugs. This hydrogel is injectable, permitting its implantation through minimally invasive approaches. Notably, this hydrogel is found to exhibit photoluminescence, enabling bioimaging and in vivo tracking. Moreover, this hydrogel system possesses excellent cell-adhesive capability, effectively promoting cell attachment, proliferation and long-term survival of various types of cells. Further, the sericin hydrogel releases bioactive reagents in a sustained manner. Additionally, this hydrogel demonstrates good elasticity, high porosity, and pH-dependent degradation dynamics, which are advantageous for this sericin hydrogel to serve as a delivery vehicle for cells and therapeutic drugs. With all these unique features, it is expected that this sericin hydrogel will have wide utility in the areas of tissue engineering and regenerative medicine. PMID:25412301

Exploring natural silk protein sericin for regenerative medicine: an injectable, photoluminescent, cell-adhesive 3D hydrogel

NASA Astrophysics Data System (ADS)

Wang, Zheng; Zhang, Yeshun; Zhang, Jinxiang; Huang, Lei; Liu, Jia; Li, Yongkui; Zhang, Guozheng; Kundu, Subhas C.; Wang, Lin

2014-11-01

Sericin, a major component of silk, has a long history of being discarded as a waste during silk processing. The value of sericin for tissue engineering is underestimated and its potential application in regenerative medicine has just begun to be explored. Here we report the successful fabrication and characterization of a covalently-crosslinked 3D pure sericin hydrogel for delivery of cells and drugs. This hydrogel is injectable, permitting its implantation through minimally invasive approaches. Notably, this hydrogel is found to exhibit photoluminescence, enabling bioimaging and in vivo tracking. Moreover, this hydrogel system possesses excellent cell-adhesive capability, effectively promoting cell attachment, proliferation and long-term survival of various types of cells. Further, the sericin hydrogel releases bioactive reagents in a sustained manner. Additionally, this hydrogel demonstrates good elasticity, high porosity, and pH-dependent degradation dynamics, which are advantageous for this sericin hydrogel to serve as a delivery vehicle for cells and therapeutic drugs. With all these unique features, it is expected that this sericin hydrogel will have wide utility in the areas of tissue engineering and regenerative medicine.

A light-trapping strategy for nanocrystalline silicon thin-film solar cells using three-dimensionally assembled nanoparticle structures.

PubMed

Ha, Kyungyeon; Jang, Eunseok; Jang, Segeun; Lee, Jong-Kwon; Jang, Min Seok; Choi, Hoseop; Cho, Jun-Sik; Choi, Mansoo

2016-02-05

We report three-dimensionally assembled nanoparticle structures inducing multiple plasmon resonances for broadband light harvesting in nanocrystalline silicon (nc-Si:H) thin-film solar cells. A three-dimensional multiscale (3DM) assembly of nanoparticles generated using a multi-pin spark discharge method has been accomplished over a large area under atmospheric conditions via ion-assisted aerosol lithography. The multiscale features of the sophisticated 3DM structures exhibit surface plasmon resonances at multiple frequencies, which increase light scattering and absorption efficiency over a wide spectral range from 350-1100 nm. The multiple plasmon resonances, together with the antireflection functionality arising from the conformally deposited top surface of the 3D solar cell, lead to a 22% and an 11% improvement in power conversion efficiency of the nc-Si:H thin-film solar cells compared to flat cells and cells employing nanoparticle clusters, respectively. Finite-difference time-domain simulations were also carried out to confirm that the improved device performance mainly originates from the multiple plasmon resonances generated from three-dimensionally assembled nanoparticle structures.

Thermal phase transition behavior of lipid layers on a single human corneocyte cell.

PubMed

Imai, Tomohiro; Nakazawa, Hiromitsu; Kato, Satoru

2013-09-01

We have improved the selected area electron diffraction method to analyze the dynamic structural change in a single corneocyte cell non-invasively stripped off from human skin surface. The improved method made it possible to obtain reliable diffraction images to trace the structural change in the intercellular lipid layers on a single corneocyte cell during heating from 24°C to 100°C. Comparison of the results with those of synchrotron X-ray diffraction experiments on human stratum corneum sheets revealed that the intercellular lipid layers on a corneocyte cell exhibit essentially the same thermal phase transitions as those in a stratum corneum sheet. These results suggest that the structural features of the lipid layers are well preserved after the mechanical stripping of the corneocyte cell. Moreover, electron diffraction analyses of the thermal phase transition behaviors of the corneocyte cells that had the lipid layers with different distributions of orthorhombic and hexagonal domains at 24°C suggested that small orthorhombic domains interconnected with surrounding hexagonal domains transforms in a continuous manner into new hexagonal domains. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Dual action of high estradiol doses on MNU-induced prostate neoplasms in a rodent model with high serum testosterone: Protective effect and emergence of unstable epithelial microenvironment.

PubMed

Gonçalves, Bianca F; de Campos, Silvana G P; Góes, Rejane M; Scarano, Wellerson R; Taboga, Sebastião R; Vilamaior, Patricia S L

2017-06-01

Estrogens are critical players in prostate growth and disease. Estrogen therapy has been the standard treatment for advanced prostate cancer for several decades; however, it has currently been replaced by alternative anti-androgenic therapies. Additionally, studies of its action on prostate biology, resulting from an association between carcinogens and estrogen, at different stages of life are scarce or inconclusive about its protective and beneficial role on induced-carcinogenesis. Thus, the aim of this study was to determine whether estradiol exerts a protective and/or stimulatory role on N-methyl-N-nitrosurea-induced prostate neoplasms. We adopted a rodent model that has been used to study induced-prostate carcinogenesis: the Mongolian gerbil. We investigated the occurrence of neoplasms, karyometric patterns, androgen and estrogen receptors, basal cells, and global methylation status in ventral and dorsolateral prostate tissues. Histopathological analysis showed that estrogen was able to slow tumor growth in both lobes after prolonged treatment. However, a true neoplastic regression was observed only in the dorsolateral prostate. In addition to the protective effects against neoplastic progression, estrogen treatment resulted in an epithelium that exhibited features distinctive from a normal prostate, including increased androgen-insensitive basal cells, high androgens and estrogen receptor positivity, and changes in DNA methylation patterns. Estrogen was able to slow tumor growth, but the epithelium exhibited features distinct from a normal prostatic epithelium, and this unstable microenvironment could trigger lesion recurrence over time. © 2017 Wiley Periodicals, Inc.

Mucin-like Region of Herpes Simplex Virus Type 1 Attachment Protein Glycoprotein C (gC) Modulates the Virus-Glycosaminoglycan Interaction*

PubMed Central

Altgärde, Noomi; Eriksson, Charlotta; Peerboom, Nadia; Phan-Xuan, Tuan; Moeller, Stephanie; Schnabelrauch, Matthias; Svedhem, Sofia; Trybala, Edward; Bergström, Tomas; Bally, Marta

2015-01-01

Glycoprotein C (gC) mediates the attachment of HSV-1 to susceptible host cells by interacting with glycosaminoglycans (GAGs) on the cell surface. gC contains a mucin-like region located near the GAG-binding site, which may affect the binding activity. Here, we address this issue by studying a HSV-1 mutant lacking the mucin-like domain in gC and the corresponding purified mutant protein (gCΔmuc) in cell culture and GAG-binding assays, respectively. The mutant virus exhibited two functional alterations as compared with native HSV-1 (i.e. decreased sensitivity to GAG-based inhibitors of virus attachment to cells and reduced release of viral particles from the surface of infected cells). Kinetic and equilibrium binding characteristics of purified gC were assessed using surface plasmon resonance-based sensing together with a surface platform consisting of end-on immobilized GAGs. Both native gC and gCΔmuc bound via the expected binding region to chondroitin sulfate and sulfated hyaluronan but not to the non-sulfated hyaluronan, confirming binding specificity. In contrast to native gC, gCΔmuc exhibited a decreased affinity for GAGs and a slower dissociation, indicating that once formed, the gCΔmuc-GAG complex is more stable. It was also found that a larger number of gCΔmuc bound to a single GAG chain, compared with native gC. Taken together, our data suggest that the mucin-like region of HSV-1 gC is involved in the modulation of the GAG-binding activity, a feature of importance both for unrestricted virus entry into the cells and release of newly produced viral particles from infected cells. PMID:26160171

Evidence that molecular changes in cells occur before morphological alterations during the progression of breast ductal carcinoma

PubMed Central

Castro, Nadia P; Osório, Cynthia ABT; Torres, César; Bastos, Elen P; Mourão-Neto, Mário; Soares, Fernando A; Brentani, Helena P; Carraro, Dirce M

2008-01-01

Introduction Ductal carcinoma in situ (DCIS) of the breast includes a heterogeneous group of preinvasive tumors with uncertain evolution. Definition of the molecular factors necessary for progression to invasive disease is crucial to determining which lesions are likely to become invasive. To obtain insight into the molecular basis of DCIS, we compared the gene expression pattern of cells from the following samples: non-neoplastic, pure DCIS, in situ component of lesions with co-existing invasive ductal carcinoma, and invasive ductal carcinoma. Methods Forty-one samples were evaluated: four non-neoplastic, five pure DCIS, 22 in situ component of lesions with co-existing invasive ductal carcinoma, and 10 invasive ductal carcinoma. Pure cell populations were isolated using laser microdissection. Total RNA was purified, DNase treated, and amplified using the T7-based method. Microarray analysis was conducted using a customized cDNA platform. The concept of molecular divergence was applied to classify the sample groups using analysis of variance followed by Tukey's test. Results Among the tumor sample groups, cells from pure DCIS exhibited the most divergent molecular profile, consequently identifying cells from in situ component of lesions with co-existing invasive ductal carcinoma as very similar to cells from invasive lesions. Additionally, we identified 147 genes that were differentially expressed between pure DCIS and in situ component of lesions with co-existing invasive ductal carcinoma, which can discriminate samples representative of in situ component of lesions with co-existing invasive ductal carcinoma from 60% of pure DCIS samples. A gene subset was evaluated using quantitative RT-PCR, which confirmed differential expression for 62.5% and 60.0% of them using initial and partial independent sample groups, respectively. Among these genes, LOX and SULF-1 exhibited features that identify them as potential participants in the malignant process of DCIS. Conclusions We identified new genes that are potentially involved in the malignant transformation of DCIS, and our findings strongly suggest that cells from the in situ component of lesions with co-existing invasive ductal carcinoma exhibit molecular alterations that enable them to invade the surrounding tissue before morphological changes in the lesion become apparent. PMID:18928525

Evidence that molecular changes in cells occur before morphological alterations during the progression of breast ductal carcinoma.

PubMed

Castro, Nadia P; Osório, Cynthia A B T; Torres, César; Bastos, Elen P; Mourão-Neto, Mário; Soares, Fernando A; Brentani, Helena P; Carraro, Dirce M

2008-01-01

Ductal carcinoma in situ (DCIS) of the breast includes a heterogeneous group of preinvasive tumors with uncertain evolution. Definition of the molecular factors necessary for progression to invasive disease is crucial to determining which lesions are likely to become invasive. To obtain insight into the molecular basis of DCIS, we compared the gene expression pattern of cells from the following samples: non-neoplastic, pure DCIS, in situ component of lesions with co-existing invasive ductal carcinoma, and invasive ductal carcinoma. Forty-one samples were evaluated: four non-neoplastic, five pure DCIS, 22 in situ component of lesions with co-existing invasive ductal carcinoma, and 10 invasive ductal carcinoma. Pure cell populations were isolated using laser microdissection. Total RNA was purified, DNase treated, and amplified using the T7-based method. Microarray analysis was conducted using a customized cDNA platform. The concept of molecular divergence was applied to classify the sample groups using analysis of variance followed by Tukey's test. Among the tumor sample groups, cells from pure DCIS exhibited the most divergent molecular profile, consequently identifying cells from in situ component of lesions with co-existing invasive ductal carcinoma as very similar to cells from invasive lesions. Additionally, we identified 147 genes that were differentially expressed between pure DCIS and in situ component of lesions with co-existing invasive ductal carcinoma, which can discriminate samples representative of in situ component of lesions with co-existing invasive ductal carcinoma from 60% of pure DCIS samples. A gene subset was evaluated using quantitative RT-PCR, which confirmed differential expression for 62.5% and 60.0% of them using initial and partial independent sample groups, respectively. Among these genes, LOX and SULF-1 exhibited features that identify them as potential participants in the malignant process of DCIS. We identified new genes that are potentially involved in the malignant transformation of DCIS, and our findings strongly suggest that cells from the in situ component of lesions with co-existing invasive ductal carcinoma exhibit molecular alterations that enable them to invade the surrounding tissue before morphological changes in the lesion become apparent.

A high-content phenotypic screen reveals the disruptive potency of quinacrine and 3',4'-dichlorobenzamil on the digestive vacuole of Plasmodium falciparum.

PubMed

Lee, Yan Quan; Goh, Amanda S P; Ch'ng, Jun Hong; Nosten, François H; Preiser, Peter Rainer; Pervaiz, Shazib; Yadav, Sanjiv Kumar; Tan, Kevin S W

2014-01-01

Plasmodium falciparum is the etiological agent of malignant malaria and has been shown to exhibit features resembling programmed cell death. This is triggered upon treatment with low micromolar doses of chloroquine or other lysosomotrophic compounds and is associated with leakage of the digestive vacuole contents. In order to exploit this cell death pathway, we developed a high-content screening method to select compounds that can disrupt the parasite vacuole, as measured by the leakage of intravacuolar Ca(2+). This assay uses the ImageStream 100, an imaging-capable flow cytometer, to assess the distribution of the fluorescent calcium probe Fluo-4. We obtained two hits from a small library of 25 test compounds, quinacrine and 3',4'-dichlorobenzamil. The ability of these compounds to permeabilize the digestive vacuole in laboratory strains and clinical isolates was validated by confocal microscopy. The hits could induce programmed cell death features in both chloroquine-sensitive and -resistant laboratory strains. Quinacrine was effective at inhibiting field isolates in a 48-h reinvasion assay regardless of artemisinin clearance status. We therefore present as proof of concept a phenotypic screening method with the potential to provide mechanistic insights to the activity of antimalarial drugs.

Morphopathological features in tissues of alpha-mannosidosis guinea pigs at different gestational ages.

PubMed

Auclair, D; Hopwood, J J

2007-10-01

Alpha-mannosidosis is an inherited metabolic disorder characterized by a reduction in alpha-D-mannosidase and intralysosomal accumulation of undegraded mannose-containing oligosaccharides. The alpha-mannosidosis guinea pig exhibits pathological similarities to its human counterpart, which make it a valuable animal model. To trace the progression of alpha-mannosidosis during foetal development, brain and visceral organs from affected and unaffected guinea pigs at 30, 36, 38, 51 and 65 days of gestation (dg) were examined by light and electron microscopy (term: approximately 68 dg). In the affected brain, distended lysosomes (vacuoles) were scarce up to 38 dg and were seen in few differentiating neuronal cells but mostly in macrophages, pericytes and endothelial cells. At 51 and 65 dg, several vacuoles were observed in some neurones, in many Purkinje cells, pericytes, endothelial and microglial cells, and in few cerebellar internal granule cells. Myelination had started by 51 dg. Non-myelinated axonal spheroids were detected in the brainstem at 65 dg. In the kidney cortex and liver, an increase in vacuolation was noticed between 36 and 65 dg. Some vacuolated cells were also noticed in the lungs and spleen at 51 and 65 dg. Altogether, these histological observations suggest that alpha-mannosidosis is unlikely to affect ontogenesis before the second half of gestation in guinea pigs; however, the morphopathological features recorded during the last quarter of gestation (which may roughly correspond to the period covering near term to 1-2 years of age in human) were clearly noticeable and may have had some impact.

Random Combinatorial Gradient Metasurface for Broadband, Wide-Angle and Polarization-Independent Diffusion Scattering.

PubMed

Zhuang, Yaqiang; Wang, Guangming; Liang, Jiangang; Cai, Tong; Tang, Xiao-Lan; Guo, Tongfeng; Zhang, Qingfeng

2017-11-29

This paper proposes an easy, efficient strategy for designing broadband, wide-angle and polarization-independent diffusion metasurface for radar cross section (RCS) reduction. A dual-resonance unit cell, composed of a cross wire and cross loop (CWCL), is employed to enhance the phase bandwidth covering the 2π range. Both oblique-gradient and horizontal-gradient phase supercells are designed for illustration. The numerical results agree well with the theoretical ones. To significantly reduce backward scattering, the random combinatorial gradient metasurface (RCGM) is subsequently constructed by collecting eight supercells with randomly distributed gradient directions. The proposed metasurface features an enhanced specular RCS reduction performance and less design complexity compared to other candidates. Both simulated and measured results show that the proposed RCGM can significantly suppress RCS and exhibits broadband, wide-angle and polarization independence features.

Adult human pancreas-derived cells expressing stage-specific embryonic antigen 4 differentiate into Sox9-expressing and Ngn3-expressing pancreatic ducts in vivo.

PubMed

Lee, Song; Lee, Chan Mi; Kim, Song Cheol

2016-11-11

Tissue-specific stem/progenitor cells are found in various adult tissues and may have the capacity for lineage-specific differentiation, facilitating applications in autologous transplantation. Stage-specific embryonic antigen 4 (SSEA-4), an early embryonic glycolipid antigen, is expressed in cells derived from adult human pancreas exocrine tissue. Here, we examined the characteristics and lineage-specific differentiation capacity of SSEA-4 + cells. Human adult partial pancreas tissues were obtained from different donors and cultured in vitro. SSEA-4 + and CA19-9 + cells were isolated from adult human pancreas exocrine cells using magnetic-activated cell sorting, and gene expression was validated by quantitative polymerase chain reaction. To confirm in-vivo differentiation, SSEA-4 + and CA19-9 + cells were transplanted into the dorsal subcutaneous region of mice. Finally, morphological features of differentiated areas were confirmed by immunostaining and morphometric analysis. SSEA-4-expressing cells were detected in isolated pancreas exocrine cells from adult humans. These SSEA-4 + cells exhibited coexpression of CA19-9, a marker of pancreatic duct cells, but not amylase expression, as shown by immunostaining and flow cytometry. SSEA-4 + cells exhibited higher relative expression of Oct4, Nanog, Klf4, Sox2, and c-Myc mRNAs than CA19-9 + cells. Pancreatic intralobular ducts (PIDs) were generated from SSEA-4 + or CA19-9 + cells in vivo at 5 weeks after transplantation. However, newly formed PIDs from CA19-9 + cells were less abundant and showed an incomplete PID morphology. In contrast, newly formed PIDs from SSEA-4 + cells were abundant in the transplanted area and showed a crowded morphology, typical of PIDs. Sox9 and Ngn3, key transcription factors associated with pancreatic development and regeneration, were expressed in PIDs from SSEA-4 + cells. SSEA-4-expressing cells in the adult human pancreas may have the potential for regeneration of the pancreas and may be used as a source of stem/progenitor cells for pancreatic cell lineage-specific differentiation.

Reversal of CD8 T-Cell–Mediated Mucocutaneous Graft-Versus-Host-Like Disease by the JAK Inhibitor Tofacitinib

PubMed Central

Okiyama, Naoko; Furumoto, Yasuko; Villarroel, Vadim A; Linton, Jay T; Tsai, Wanxia L; Gutermuth, Jan; Ghoreschi, Kamran; Gadina, Massimo; O'Shea, John J; Katz, Stephen I

2014-01-01

The utility of allogeneic hematopoietic stem cell transplantation is limited by graft-versus-host disease (GVHD), a significant cause of morbidity and mortality. Patients with GVHD exhibit cutaneous manifestations with histological features of interface dermatitis followed by scleroderma-like changes. JAK inhibitors represent a class of immunomodulatory drugs that inhibit signaling by multiple cytokines. Herein we report the effects of tofacitinib in a murine model of GVHD. Oral administration of tofacitinib prevented GVHD-like disease manifested by weight loss and mucocutaneous lesions. More importantly, tofacitinib was also effective in reversing established disease. Tofacitinib diminished the expansion and activation of murine CD8 T cells in this model, and had similar effects on IL-2-stimulated human CD8 T cells. Tofacitinib also inhibited the expression of IFN-γ-inducible chemoattractants by keratinocytes, and IFN-γ-inducible cell death of keratinocytes. Tofacitinib may be an effective drug for treatment against CD8 T-cell–mediated mucocutaneous diseases in patients with GVHD. PMID:24213371

Glomus tumor of the liver in a cow

PubMed Central

HORIUCHI, Noriyuki; KOMAGATA, Makoto; SHITAMURA, Keiichi; CHIBA, Shiori; MATSUMOTO, Kotaro; INOKUMA, Hisashi; MATSUI, Takane; KOBAYASHI, Yoshiyasu

2015-01-01

An 11-year-old Holstein-Friesian cow exhibited anorexia and jaundice. A large mass was found in the liver during necropsy. Macroscopically, the mass was composed of dark red multilobular tissue and a centrally located abscess, which was connected to the hepatic duct. Histologically, the mass consisted of proliferation of small neoplastic cells and was demarcated from the hepatic parenchyma by a thick region of granulation tissue. The neoplastic cells were predominantly arranged in solid sheets, but they also formed blood-filled cancellous structures, and proliferating foci were seen around blood vessels. Periodic acid-Schiff reaction demonstrated that a fine basement membrane-like structure surrounded the neoplastic cells. Immunohistochemically, the neoplastic cells were positive for vimentin and alpha smooth muscle actin and negative for cytokeratin, factor VIII-related antigen, chromogranin and desmin. Based on its histopathological features, the hepatic neoplasm was diagnosed as a primary glomus tumor. This is the first report about a primary glomus tumor of the liver in a cow. PMID:25715802

On the self-association potential of transmembrane tight junction proteins.

PubMed

Blasig, I E; Winkler, L; Lassowski, B; Mueller, S L; Zuleger, N; Krause, E; Krause, G; Gast, K; Kolbe, M; Piontek, J

2006-02-01

Tight junctions seal intercellular clefts via membrane-related strands, hence, maintaining important organ functions. We investigated the self-association of strand-forming transmembrane tight junction proteins. The regulatory tight junction protein occludin was differently tagged and cotransfected in eucaryotic cells. These occludins colocalized within the plasma membrane of the same cell, coprecipitated and exhibited fluorescence resonance energy transfer. Differently tagged strand-forming claudin-5 also colocalized in the plasma membrane of the same cell and showed fluorescence resonance energy transfer. This demonstrates self-association in intact cells both of occludin and claudin-5 in one plasma membrane. In search of dimerizing regions of occludin, dimerization of its cytosolic C-terminal coiledcoil domain was identified. In claudin-5, the second extracellular loop was detected as a dimer. Since the transmembrane junctional adhesion molecule also is known to dimerize, the assumption that homodimerization of transmembrane tight junction proteins may serve as a common structural feature in tight junction assembly is supported.

Engineering a nanostructured "super surface" with superhydrophobic and superkilling properties.

PubMed

Hasan, Jafar; Raj, Shammy; Yadav, Lavendra; Chatterjee, Kaushik

2015-05-12

We present a nanostructured "super surface" fabricated using a simple recipe based on deep reactive ion etching of a silicon wafer. The topography of the surface is inspired by the surface topographical features of dragonfly wings. The super surface is comprised of nanopillars 4 μm in height and 220 nm in diameter with random inter-pillar spacing. The surface exhibited superhydrophobicity with a static water contact angle of 154.0° and contact angle hysteresis of 8.3°. Bacterial studies revealed the bactericidal property of the surface against both gram negative ( Escherichia coli ) and gram positive ( Staphylococcus aureus ) strains through mechanical rupture of the cells by the sharp nanopillars. The cell viability on these nanostructured surfaces was nearly six-fold lower than on the unmodified silicon wafer. The nanostructured surface also killed mammalian cells (mouse osteoblasts) through mechanical rupture of the cell membrane. Thus, such nanostructured super surfaces could find applications for designing self-cleaning and anti-bacterial surfaces in diverse applications such as microfluidics, surgical instruments, pipelines and food packaging.

Ovarian teratoma displaying a wide variety of tissue components in a broiler chicken (Gallus Domesticus): morphological heterogeneity of pluripotential germ cell during tumorigenesis.

PubMed

Ohfuji, S

2016-01-01

Spontaneous ovarian teratoma was found in a seven-week-old female Chunky broiler chicken that was slaughtered for food. On post-mortem inspection, a spherical tumor mass attaching to a juvenile ovary was found in the abdominal cavity. Histopathologically, the tumor was comprised of immature mesenchymal stroma and a variety of mature tissue elements of mesodermal and ectodermal origin. In addition, there were multiple indistinguishable tissue elements, which showed no malignant cytological features but were unidentifiable as to corresponding embryological layer of origin. These heterogeneous teratoma tissues consisted of a variety of glandular, cystic, duct-like, and tubular structures, some of which exhibited a lining by a mixture of both keratinizing/non-keratinizing stratified squamous epithelial cells and cuboidal/columnar epithelial cells. The ovarian tetatoma was considered a benign and congenital one. The highly diverse differentiation of the teratoma might have manifested a morphological aspect of intrinsic character of the pluripotential germ cells during tumorigenesis.

Cell internalizable and intracellularly degradable cationic polyurethane micelles as a potential platform for efficient imaging and drug delivery.

PubMed

Ding, Mingming; Zeng, Xin; He, Xueling; Li, Jiehua; Tan, Hong; Fu, Qiang

2014-08-11

A cell internalizable and intracellularly degradable micellar system, assembled from multiblock polyurethanes bearing cell-penetrating gemini quaternary ammonium pendent groups in the side chain and redox-responsive disulfide linkages throughout the backbone, was developed for potential magnetic resonance imaging (MRI) and drug delivery. The nanocarrier is featured as a typical "cleavable core-internalizable shell-protective corona" architecture, which exhibits small size, positive surface charge, high loading capacity, and reduction-triggered destabilization. Furthermore, it can rapidly enter tumor cells and release its cargo in response to an intracellular level of glutathione, resulting in enhanced drug efficacy in vitro. The magnetic micelles loaded with superparamagnetic iron oxide (SPIO) nanoparticles demonstrate excellent MRI contrast enhancement, with T2 relaxivity found to be affected by the morphology of SPIO-clustering inside the micelle core. The multifunctional carrier with good cytocompatibility and nontoxic degradation products can serve as a promising theranostic candidate for efficient intracellular delivery of anticancer drugs and real-time monitoring of therapeutic effect.

Keratin 17 null mice exhibit age- and strain-dependent alopecia

PubMed Central

McGowan, Kevin M.; Tong, Xuemei; Colucci-Guyon, Emma; Langa, Francina; Babinet, Charles; Coulombe, Pierre A.

2002-01-01

Onset of type I keratin 17 (K17) synthesis marks the adoption of an appendageal fate within embryonic ectoderm, and its expression persists in specific cell types within mature hair, glands, and nail. We report that K17 null mice develop severe alopecia during the first week postbirth, correlating with hair fragility, alterations in follicular histology, and apoptosis in matrix cells. These alterations are incompletely penetrant and normalize starting with the first postnatal cycle. Absence of a hair phenotype correlates with a genetic strain-dependent compensation by related keratins, including K16. These findings reveal a crucial role for K17 in the structural integrity of the first hair produced and the survival of hair-producing cells. Given that identical inherited mutations in this gene can cause either pachyonychia congenita or steatocystoma multiplex, the features of this mouse model suggest that this clinical heterogeneity arises from a cell type-specific, genetically determined compensation by related keratins. PMID:12050118

Histochemical carbonic anhydrase in rat inner medullary collecting duct

NASA Technical Reports Server (NTRS)

Kleinman, J. G.; Bain, J. L.; Fritsche, C.; Riley, D. A.

1992-01-01

Rat inner medullary collecting duct (IMCD) secretes substantial amounts of H+. However, carbonic anhydrase (CA), a concomitant of H+ secretion, has been generally reported absent in this segment. To reexamine this problem, we investigated CA and the morphological phenotypes of cells comprising the IMCD by CA histochemistry, using a modified Hansson technique with light and electron microscopy. Throughout the medulla, tubule cells exhibit histochemical CA activity. In the initial third of the inner medulla, a small proportion have features of intercalated cells and demonstrate some degree of CA activity. However, the majority population in the early portions of the IMCD appears to consist of principal cells. These also show CA staining of widely variable intensity, both among and within cells. A third cell type, previously called "IMCD cells", appears in the middle portion of the IMCD and is the only cell type present near the papilla tip. In contrast to previous reports, these "IMCD cells" have histochemical CA staining, also of highly variable intensity. These results demonstrate that stainable carbonic anhydrase to support acidification is present throughout the rat IMCD, both in intercalated cells and in some cells clearly not of this type. Therefore, the presence of CA is not specific for the intercalated cell type and suggests that other cell types may participate in acid secretion in IMCD.

The circadian clock in skin: implications for adult stem cells, tissue regeneration, cancer, aging, and immunity

PubMed Central

Plikus, Maksim V.; Van Spyk, Elyse Noelani; Pham, Kim; Geyfman, Mikhail; Kumar, Vivek; Takahashi, Joseph S.; Andersen, Bogi

2015-01-01

Historically work on peripheral circadian clocks has been focused on organs and tissues that have prominent metabolic functions, such as liver, fat and muscle. In recent years, skin is emerging as a model for studying circadian clock regulation of cell proliferation, stem cell functions, tissue regeneration, aging and carcinogenesis. Morphologically skin is complex, containing multiple cell types and structures, and there is evidence for a functional circadian clock in most, if not all, of its cell types. Despite the complexity, skin stem cell populations are well defined, experimentally tractable and exhibit prominent daily cell proliferation cycles. Hair follicle stem cells also participate in recurrent, long-lasting cycles of regeneration -- the hair growth cycles. Among other advantages of skin is a broad repertoire of available genetic tools enabling the creation of cell-type specific circadian mutants. Also, due to the accessibility of the skin, in vivo imaging techniques can be readily applied to study the circadian clock and its outputs in real time, even at the single-cell level. Skin provides the first line of defense against many environmental and stress factors that exhibit dramatic diurnal variations such as solar UV radiation and temperature. Studies have already linked the circadian clock to the control of UVB-induced DNA damage and skin cancers. Due to the important role that skin plays in the defense against microorganisms, it represents a promising model system to further explore the role of the clock in the regulation of the body's immune functions. To that end, recent studies have already linked the circadian clock to psoriasis, one of the most common immune-mediated skin disorders. The skin also provides opportunities to interrogate clock regulation of tissue metabolism in the context of stem cells and regeneration. Furthermore, many animal species feature prominent seasonal hair molt cycles, offering an attractive model for investigating the role of clock in seasonal organismal behaviors. PMID:25589491

B-cell lymphomas with concurrent IGH-BCL2 and MYC rearrangements are aggressive neoplasms with clinical and pathologic features distinct from Burkitt lymphoma and diffuse large B-cell lymphoma.

PubMed

Snuderl, Matija; Kolman, Olga K; Chen, Yi-Bin; Hsu, Jessie J; Ackerman, Adam M; Dal Cin, Paola; Ferry, Judith A; Harris, Nancy Lee; Hasserjian, Robert P; Zukerberg, Lawrence R; Abramson, Jeremy S; Hochberg, Ephraim P; Lee, Hang; Lee, Alfred I; Toomey, Christiana E; Sohani, Aliyah R

2010-03-01

B-cell lymphomas with concurrent IGH-BCL2 and MYC rearrangements, also known as "double-hit" lymphomas (DHL), are rare neoplasms characterized by highly aggressive clinical behavior, complex karyotypes, and a spectrum of pathologic features overlapping with Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL) and B-lymphoblastic lymphoma/leukemia (B-LBL). The clinical and pathologic spectrum of this rare entity, including comparison to other high-grade B-cell neoplasms, has not been well defined. We conducted a retrospective analysis of clinical and pathologic features of 20 cases of DHL seen at our institution during a 5-year period. In addition, we carried out case-control comparisons of DHL with BL and International Prognostic Index (IPI)-matched DLBCL. The 11 men and 9 women had a median age of 63.5 years (range 32 to 91). Six patients had a history of grade 1 to 2 follicular lymphoma; review of the prior biopsy specimens in 2 of 5 cases revealed blastoid morphology. Eighteen patients had Ann Arbor stage 3 or 4 disease and all had elevated serum lactate dehydrogenase (LDH) levels at presentation. Extranodal disease was present in 17/20 (85%), bone marrow involvement in 10/17 (59%) and central nervous system (CNS) disease in 5/11 (45%). Nineteen patients were treated with combination chemotherapy, of whom 18 received rituximab and 14 received CNS-directed therapy. Fourteen patients (70%) died within 8 months of diagnosis. Median overall survival in the DHL group (4.5 mo) was inferior to both BL (P=0.002) and IPI-matched DLBCL (P=0.04) control patients. Twelve DHL cases (60%) were classified as B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL, 7 cases (35%) as DLBCL, not otherwise specified, and 1 case as B-LBL. Distinguishing features from BL included expression of Bcl2 (P<0.0001), Mum1/IRF4 (P=0.006), Ki-67 <95% (P<0.0001), and absence of EBV-EBER (P=0.006). DHL commonly contained the t(8;22) rather than the t(8;14) seen in most BL controls (P=0.001), and exhibited a higher number of chromosomal aberrations (P=0.0009). DHL is a high-grade B-cell neoplasm with a poor prognosis, resistance to multiagent chemotherapy, and clinical and pathologic features distinct from other high-grade B-cell neoplasms. Familiarity with the morphologic and immunophenotypic spectrum of DHL is important in directing testing to detect concurrent IGH-BCL2 and MYC rearrangements when a karyotype is unavailable. The aggressive clinical behavior and combination of genetic abnormalities seen in these cases may warrant categorization as a separate entity in future classifications and call for novel therapeutic approaches.

Trail networks formed by populations of immune cells

NASA Astrophysics Data System (ADS)

Yang, Taeseok Daniel; Kwon, Tae Goo; Park, Jin-sung; Lee, Kyoung J.

2014-02-01

Populations of biological cells that communicate with each other can organize themselves to generate large-scale patterns. Examples can be found in diverse systems, ranging from developing embryos, cardiac tissues, chemotaxing ameba and swirling bacteria. The similarity, often shared by the patterns, suggests the existence of some general governing principle. On the other hand, rich diversity and system-specific properties are exhibited, depending on the type of involved cells and the nature of their interactions. The study on the similarity and the diversity constitutes a rapidly growing field of research. Here, we introduce a new class of self-organized patterns of cell populations that we term as ‘cellular trail networks’. They were observed with populations of rat microglia, the immune cells of the brain and the experimental evidence suggested that haptotaxis is the key element responsible for them. The essential features of the observed patterns are well captured by the mathematical model cells that actively crawl and interact with each other through a decomposing but non-diffusing chemical attractant laid down by the cells. Our finding suggests an unusual mechanism of socially cooperative long-range signaling for the crawling immune cells.

Structural and elemental changes in glioblastoma cells in situ: complementary imaging with high resolution visible light- and X-ray microscopy

DOE PAGES

Ducic, Tanja; Paunesku, Tatjana; Chen, Si; ...

2016-12-09

The glioblastoma (GBM) is characterized by a short median survival and an almost 100% tumor related mortality. GBM cells exhibit highly invasive behavior whose mechanisms are not yet fully understood. The present study explores application of X-ray and visible light microscopy to display the elemental and structural images of cells from 3 patient derived GMB samples and an established GMB cell line. Slight differences in elemental concentrations, in actin cytoskeleton organization and cell morphology were noted between all cells types by X-ray fluorescence and full field soft X-ray microscopy, as well as the Structured Illumination Super-resolution Microscope (SIM). Different samplemore » preparation approaches were used to match each imaging technique. While preparation for SIM included cell fixation and staining, intact frozen hydrated cells were used for the trace element imaging by hard X-ray fluorescence and exploration of the structural features by soft X-ray absorption tomography. In conclusion, each technique documented differences between samples with regard to morphology and elemental composition and underscored the importance of use of multiple patient derived samples for detailed GBM study.« less

Structural and elemental changes in glioblastoma cells in situ: complementary imaging with high resolution visible light- and X-ray microscopy

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

Ducic, Tanja; Paunesku, Tatjana; Chen, Si

The glioblastoma (GBM) is characterized by a short median survival and an almost 100% tumor related mortality. GBM cells exhibit highly invasive behavior whose mechanisms are not yet fully understood. The present study explores application of X-ray and visible light microscopy to display the elemental and structural images of cells from 3 patient derived GMB samples and an established GMB cell line. Slight differences in elemental concentrations, in actin cytoskeleton organization and cell morphology were noted between all cells types by X-ray fluorescence and full field soft X-ray microscopy, as well as the Structured Illumination Super-resolution Microscope (SIM). Different samplemore » preparation approaches were used to match each imaging technique. While preparation for SIM included cell fixation and staining, intact frozen hydrated cells were used for the trace element imaging by hard X-ray fluorescence and exploration of the structural features by soft X-ray absorption tomography. In conclusion, each technique documented differences between samples with regard to morphology and elemental composition and underscored the importance of use of multiple patient derived samples for detailed GBM study.« less

'Hints' in the killer protein gasdermin D: unveiling the secrets of gasdermins driving cell death.

PubMed

Qiu, Shiqiao; Liu, Jing; Xing, Feiyue

2017-04-01

Pyroptosis is a lytic form of cell death distinguished from apoptosis, ferroptosis, necrosis, necroptosis, NETosis, oncosis, pyronecrosis and autophagy. Proinflammatory caspases cleave a gasdermin D (GSDMD) protein to generate a 31 kDa N-terminal domain. The cleavage relieves the intramolecular inhibition on the gasdermin-N domain, which then moves to the plasma membrane to exhibit pore-forming activity. Thus, GSDMD acts as the final and direct executor of pyroptotic cell death. Owing to the selective targeting of the inner leaflet of the plasma membrane with the pore-forming that determines pyroptotic cell death, GSDMD could be a potential target to control cell death or extracellular bacterial infections. Intriguingly, other gasdermin family members also share similar N-terminal domains, but they present different cell death programs. Herein, we summarize features and functions of the novel player proteins in cell death, including GSDMD triggering pyroptosis, Gsdma3/GSDMA initiating autophagy/apoptosis and DFNA5 inducing apoptosis/secondary necrosis. The gasdermin N terminus appears to be a novel pore-forming protein. This provides novel insight into the underlying roles and mechanisms of lytic or nonlytic forms of programmed cell death, as well as their potential applications in inflammation-associated diseases.

Homeobox NKX2-3 promotes marginal-zone lymphomagenesis by activating B-cell receptor signalling and shaping lymphocyte dynamics

PubMed Central

Robles, Eloy F.; Mena-Varas, Maria; Barrio, Laura; Merino-Cortes, Sara V.; Balogh, Péter; Du, Ming-Qing; Akasaka, Takashi; Parker, Anton; Roa, Sergio; Panizo, Carlos; Martin-Guerrero, Idoia; Siebert, Reiner; Segura, Victor; Agirre, Xabier; Macri-Pellizeri, Laura; Aldaz, Beatriz; Vilas-Zornoza, Amaia; Zhang, Shaowei; Moody, Sarah; Calasanz, Maria Jose; Tousseyn, Thomas; Broccardo, Cyril; Brousset, Pierre; Campos-Sanchez, Elena; Cobaleda, Cesar; Sanchez-Garcia, Isidro; Fernandez-Luna, Jose Luis; Garcia-Muñoz, Ricardo; Pena, Esther; Bellosillo, Beatriz; Salar, Antonio; Baptista, Maria Joao; Hernandez-Rivas, Jesús Maria; Gonzalez, Marcos; Terol, Maria Jose; Climent, Joan; Ferrandez, Antonio; Sagaert, Xavier; Melnick, Ari M.; Prosper, Felipe; Oscier, David G.; Carrasco, Yolanda R.; Dyer, Martin J. S.; Martinez-Climent, Jose A.

2016-01-01

NKX2 homeobox family proteins have a role in cancer development. Here we show that NKX2-3 is overexpressed in tumour cells from a subset of patients with marginal-zone lymphomas, but not with other B-cell malignancies. While Nkx2-3-deficient mice exhibit the absence of marginal-zone B cells, transgenic mice with expression of NKX2-3 in B cells show marginal-zone expansion that leads to the development of tumours, faithfully recapitulating the principal clinical and biological features of human marginal-zone lymphomas. NKX2-3 induces B-cell receptor signalling by phosphorylating Lyn/Syk kinases, which in turn activate multiple integrins (LFA-1, VLA-4), adhesion molecules (ICAM-1, MadCAM-1) and the chemokine receptor CXCR4. These molecules enhance migration, polarization and homing of B cells to splenic and extranodal tissues, eventually driving malignant transformation through triggering NF-κB and PI3K-AKT pathways. This study implicates oncogenic NKX2-3 in lymphomagenesis, and provides a valid experimental mouse model for studying the biology and therapy of human marginal-zone B-cell lymphomas. PMID:27297662

Active matter model of Myxococcus xanthus aggregation

NASA Astrophysics Data System (ADS)

Patch, Adam; Bahar, Fatmagul; Liu, Guannan; Thutupalli, Shashi; Welch, Roy; Yllanes, David; Shaevitz, Joshua; Marchetti, M. Cristina

Myxococcus xanthus is a soil-dwelling bacterium that exhibits several fascinating collective behaviors including streaming, swarming, and generation of fruiting bodies. A striking feature of M. xanthus is that it periodically reverses its motility direction. The first stage of fruiting body formation is characterized by the aggregation of cells on a surface into round mesoscopic structures. Experiments have shown that this aggregation relies heavily on regulation of the reversal rate and local mechanical interactions, suggesting motility-induced phase separation may play an important role. We have adapted self-propelled particle models to include cell reversal and motility suppression resulting from sporulation observed in aggregates. Using 2D molecular dynamics simulations, we map the phase behavior in the space of Péclet number and local density and examine the kinetics of aggregation for comparison to experiments.

PBP deletion mutants of Escherichia coli exhibit irregular distribution of MreB at the deformed zones.

PubMed

Vijayan, Saptha; Mallick, Sathi; Dutta, Mouparna; Narayani, M; Ghosh, Anindya S

2014-02-01

MreB is a cytoskeletal protein, which is responsible for maintaining proper cellular morphology and is essential for cell survival. Likewise, penicillin-binding protein 5 (PBP5) helps in maintaining cell shape, though non-essential for survival. The contradicting feature of these two proteins paves the way for this study, wherein we attempt to draw a relation on the nature of distribution of MreB in PBP deletion mutants. The study revealed that the uniform MreB helices/patches were destabilized/disturbed at the zone of deformities of the PBP mutants, whereas the helical patterns were retained at the regions maintaining a rod shape. We interpret that MreB remains functional irrespective of its distribution being misguided by the aberrant shapes of PBP mutants.

Ultrathin Polyaniline-based Buffer Layer for Highly Efficient Polymer Solar Cells with Wide Applicability

PubMed Central

Zhao, Wenchao; Ye, Long; Zhang, Shaoqing; Fan, Bin; Sun, Mingliang; Hou, Jianhui

2014-01-01

Interfacial buffer layers often attribute the improved device performance in organic optoelectronic device. Herein, a water-soluble hydrochloric acid doped polyanilines (HAPAN) were utilized as p-type electrode buffer layer in highly efficient polymer solar cells (PSC) based on PBDTTT-EFT and several representative polymers. The PBDTTT-EFT-based conventional PSC featuring ultrathin HAPAN (1.3 nm) delivered high PCE approximately 9%, which is one of the highest values among conventional PSC devices. Moreover, ultrathin HAPAN also exhibited wide applicability in a variety of efficient photovoltaic polymers including PBDTTT-C-T, PTB7, PBDTBDD, PBTTDPP-T, PDPP3T and P3HT. The excellent performances were originated from the high transparency, small film roughness and suitable work function. PMID:25300365

An Aurivillius Oxide Based Cathode with Excellent CO2 Tolerance for Intermediate-Temperature Solid Oxide Fuel Cells.

PubMed

Zhu, Yinlong; Zhou, Wei; Chen, Yubo; Shao, Zongping

2016-07-25

The Aurivillius oxide Bi2 Sr2 Nb2 MnO12-δ (BSNM) was used as a cobalt-free cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). To the best of our knowledge, the BSNM oxide is the only alkaline-earth-containing cathode material with complete CO2 tolerance that has been reported thus far. BSNM not only shows favorable activity in the oxygen reduction reaction (ORR) at intermediate temperatures but also exhibits a low thermal expansion coefficient, excellent structural stability, and good chemical compatibility with the electrolyte. These features highlight the potential of the new BSNM material as a highly promising cathode material for IT-SOFCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Village Power Exhibit Featured at NREL's Visitors Center

Science.gov Websites

World Energy" Expo Slated for February-April For more information contact: Gary Schmitz, 303-275 is a feature attraction of NREL's Visitors Center "Powering Our Lives, Powering Our World" , Powering Our World" Energy Expo begins Feb. 20 with the opening of the Village Power exhibit, and

76 FR 45646 - Culturally Significant Objects Imported for Exhibition Determinations: “5,000 Years of Chinese...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-29

... DEPARTMENT OF STATE [Public Notice: 7540] Culturally Significant Objects Imported for Exhibition Determinations: ``5,000 Years of Chinese Jade Featuring Selections From the National Museum of Taiwan and the... ``5,000 Years of Chinese Jade Featuring Selections from the National Museum of Taiwan and the Arthur M...

The cytologic features of NUT midline carcinoma.

PubMed

Bellizzi, Andrew M; Bruzzi, Cynthia; French, Christopher A; Stelow, Edward B

2009-12-25

Nuclear protein in testis (NUT) midline carcinoma (NMC) represents an aggressive, high-grade carcinoma typically involving the upper aerodigestive tract or mediastinum. Although the tumor was originally noted in young persons, we have subsequently identified 5 adult cases. To our knowledge, the cytology of NMC has not been systematically described. We recently published a series of NMCs identified by fluorescent in situ hybridization for characteristic NUT rearrangement. Three of these patients had undergone fine-needle aspiration. Patient age, sex, primary tumor location, and aspiration site were noted. Cases were assessed for the following: cellularity, architecture, cytoplasm, cell size, nuclear contours, nucleoli, chromatin, anisonucleosis/cytosis, mitotic activity, background, and nuclear crush. The 3 cases occurred in 2 women and 1 man, ages 31-79 years. Primaries involved the sinonasal tract (2) and larynx. Aspirates were of right neck masses (2) and supraclavicular lymph node. Smears were highly cellular and generally noncohesive. Cytoplasm was scant/delicate, although occasional cells with denser cytoplasm were noted in 1 case. Cells were 2-3 times the diameter of a small lymphocyte with irregular nuclear contours, discrete nucleoli, and fine/granular to vesicular chromatin. Anisonucleosis/cytosis was slight to moderate. Mitotic figures were noted in each case. The background contained naked nuclei and karyorrhectic debris; nuclear crush was noted. NMCs exhibit cytologic features of a poorly differentiated or undifferentiated carcinoma. Although reports mention squamous differentiation as a histologic feature, it is typically focal, and overt squamous differentiation was not identified in our cases. Given morphologic overlap with other high-grade carcinomas, diagnosis requires a high index of suspicion. (c) 2009 American Cancer Society.

Clinical, Cytological, Histological and Immunohistochemical Features of Cutaneous Mast Cell Tumours in Ferrets (Mustela putorius furo).

PubMed

Vilalta, L; Meléndez-Lazo, A; Doria, G; Ramis, A; Solano-Gallego, L; Pastor, J; Martorell, J

2016-11-01

Cutaneous mast cell tumours (cMCTs) are one of the most common cutaneous tumours in ferrets (Mustela putorius furo). However, limited information is available regarding cytological and histological features of these tumours and studies evaluating KIT expression are lacking in this species. The aims of this prospective study were to describe the most common clinical, cytological and histological features of cMCTs in ferrets and to compare the usefulness of different staining techniques in the diagnosis of these tumours in ferrets as well as evaluating KIT expression in neoplastic mast cells (MCs) by immunohistochemistry. Macroscopically, the tumours were small, round to plaque-like and frequently associated with surface crusting. The most common locations were the extremities and the trunk. MC granules were stained in all cases using toluidine blue (TB) and Wright-Giemsa stains in cytological specimens, but none stained with modified Wright's stain. Haematoxylin and eosin and TB on histological sections failed to stain MC granules in all the cases. Cytological and histological examination revealed low to moderate anisocytosis and anisokaryosis. An infiltrative rather than a delineated or encapsulated growth pattern was noted histologically in all cases. Eosinophilic infiltration was not uncommon and 'collagenolysis' was detected on cytological and histological examination. KIT expression was detected in all cases evaluated. In approximately one third of the cases the MCs exhibited KIT labelling pattern I and in the remaining ferrets, KIT pattern III. No correlation was found between KIT expression pattern and biological behaviour. Copyright © 2016 Elsevier Ltd. All rights reserved.

Increased erythrocyte deformability in fetal erythropoiesis and in erythrocytes deficient in glucose-6-phosphate dehydrogenase and other glycolytic enzymes.

PubMed

Johnson, R M; Panchoosingh, H; Goyette, G; Ravindranath, Y

1999-01-01

Erythrocyte deformability was determined in more than 500 clinical samples, and was found to be elevated in conditions in which fetal-like red cells are produced: aplastic anemia (3/3 cases), myelodysplastic syndromes, polycythemias, sickle cell anemia during treatment with hydroxyurea, paroxysmal nocturnal hemoglobinuria, and recovery from B12 deficiency. Elevated deformability was observed in neonatal erythrocytes, and during recovery from transient erythroblastopenia of childhood, when fetal-like red cells are known to be produced. Increased deformability appears to be a feature of fetal and fetal-like red cells. Forty-eight cases of enzymatically verified glucose-6-phosphate (G-6-PD) deficiency were also examined. Thirty out of 32 G-6-PD(A-) individuals, including both heterozygotes and hemizygotes, exhibited increased deformability during the steady state. In contrast, G-6-PD(Med) hemizygotes had normal deformability. Increased deformability was also found in G-6-PD(Huron) (n=3), G-6-PD(Wayne) (n=4), triose phosphate isomerase deficiency (n=2), and pyruvate kinase deficiency (n=2). An elevated osmoscan was found in more than 90% of female G-6-PD heterozygotes, affording a simple screening test for heterozygotes. Deformability remained high during hemolytic episodes, when older enzyme deficient cells are removed from the circulation. In four cases of G-6-PD deficiency with normal deformability, evidence for co-existing hereditary spherocytosis was found. The combination of conditions with opposing effects on deformability resulted in nearly normal deformability. Because increased red cell deformability is a feature of fetal erythrocytes, these results suggest that the red cells in many cases of glycolytic enzyme deficiency are fetal-like.

Model-based analysis of pattern motion processing in mouse primary visual cortex

PubMed Central

Muir, Dylan R.; Roth, Morgane M.; Helmchen, Fritjof; Kampa, Björn M.

2015-01-01

Neurons in sensory areas of neocortex exhibit responses tuned to specific features of the environment. In visual cortex, information about features such as edges or textures with particular orientations must be integrated to recognize a visual scene or object. Connectivity studies in rodent cortex have revealed that neurons make specific connections within sub-networks sharing common input tuning. In principle, this sub-network architecture enables local cortical circuits to integrate sensory information. However, whether feature integration indeed occurs locally in rodent primary sensory areas has not been examined directly. We studied local integration of sensory features in primary visual cortex (V1) of the mouse by presenting drifting grating and plaid stimuli, while recording the activity of neuronal populations with two-photon calcium imaging. Using a Bayesian model-based analysis framework, we classified single-cell responses as being selective for either individual grating components or for moving plaid patterns. Rather than relying on trial-averaged responses, our model-based framework takes into account single-trial responses and can easily be extended to consider any number of arbitrary predictive models. Our analysis method was able to successfully classify significantly more responses than traditional partial correlation (PC) analysis, and provides a rigorous statistical framework to rank any number of models and reject poorly performing models. We also found a large proportion of cells that respond strongly to only one stimulus class. In addition, a quarter of selectively responding neurons had more complex responses that could not be explained by any simple integration model. Our results show that a broad range of pattern integration processes already take place at the level of V1. This diversity of integration is consistent with processing of visual inputs by local sub-networks within V1 that are tuned to combinations of sensory features. PMID:26300738

KSC-2014-3135

NASA Image and Video Library

2014-07-03

CAPE CANAVERAL, Fla. – Samples of Earth rocks and real meteorites are featured in an interactive display at the new Great Balls of Fire exhibit at NASA’s Kennedy Space Center Visitor Complex in Florida. The grand opening featured remarks by former NASA astronaut Tom Jones, and Therrin Protze, chief operating officer at Delaware North Parks and Resorts at the visitor complex. Great Balls of Fire shares the story of the origins of our solar system, asteroids and comets and their possible impacts and risks. The 1,500-square-foot exhibit, located in the East Gallery of the IMAX theatre at the visitor complex, features several interactive displays, real meteorites and replica asteroid models. The exhibit is a production of The Space Science Institute's National Center for Interactive Learning. It is a traveling exhibition that also receives funding from NASA and the National Science Foundation. Photo credit: NASA/Daniel Casper

Co-immobilization of glucoamylase and glucose oxidase for electrochemical sequential enzyme electrode for starch biosensor and biofuel cell.

PubMed

Lang, Qiaolin; Yin, Long; Shi, Jianguo; Li, Liang; Xia, Lin; Liu, Aihua

2014-01-15

A novel electrochemical sequential biosensor was constructed by co-immobilizing glucoamylase (GA) and glucose oxidase (GOD) on the multi-walled carbon nanotubes (MWNTs)-modified glassy carbon electrode (GCE) by chemical crosslinking method, where glutaraldehyde and bovine serum albumin was used as crosslinking and blocking agent, respectively. The proposed biosensor (GA/GOD/MWNTs/GCE) is capable of determining starch without using extra sensors such as Clark-type oxygen sensor or H2O2 sensor. The current linearly decreased with the increasing concentration of starch ranging from 0.005% to 0.7% (w/w) with the limit of detection of 0.003% (w/w) starch. The as-fabricated sequential biosensor can be applicable to the detection of the content of starch in real samples, which are in good accordance with traditional Fehling's titration. Finally, a stable starch/O2 biofuel cell was assembled using the GA/GOD/MWNTs/GCE as bioanode and laccase/MWNTs/GCE as biocathode, which exhibited open circuit voltage of ca. 0.53 V and the maximum power density of 8.15 μW cm(-2) at 0.31 V, comparable with the other glucose/O2 based biofuel cells reported recently. Therefore, the proposed biosensor exhibited attractive features such as good stability in weak acidic buffer, good operational stability, wide linear range and capable of determination of starch in real samples as well as optimal bioanode for the biofuel cell. Copyright © 2013 Elsevier B.V. All rights reserved.

Ab Initio Simulation of Charge Transfer at the Semiconductor Quantum Dot/TiO 2 Interface in Quantum Dot-Sensitized Solar Cells

DOE PAGES

Xin, Xukai; Li, Bo; Jung, Jaehan; ...

2014-07-24

Quantum dot-sensitized solar cells (QDSSCs) have emerged as a promising solar architecture for next-generation solar cells. The QDSSCs exhibit a remarkably fast electron transfer from the quantum dot (QD) donor to the TiO 2 acceptor with size quantization properties of QDs that allows for the modulation of band energies to control photoresponse and photoconversion efficiency of solar cells. In order to understand the mechanisms that underpin this rapid charge transfer, the electronic properties of CdSe and PbSe QDs with different sizes on the TiO 2 substrate are simulated using a rigorous ab initio density functional method. Our method capitalizes onmore » localized orbital basis set, which is computationally less intensive. Quite intriguingly, a remarkable set of electron bridging states between QDs and TiO 2 occurring via the strong bonding between the conduction bands of QDs and TiO 2 is revealed. Such bridging states account for the fast adiabatic charge transfer from the QD donor to the TiO 2 acceptor, and may be a general feature for strongly coupled donor/acceptor systems. All the QDs/TiO 2 systems exhibit type II band alignments, with conduction band offsets that increase with the decrease in QD size. This facilitates the charge transfer from QDs donors to TiO 2 acceptors and explains the dependence of the increased charge transfer rate with the decreased QD size.« less

Low reversibility of intracellular cAMP accumulation in mouse Leydig tumor cells (MLTC-1) stimulated by human Luteinizing Hormone (hLH) and Chorionic Gonadotropin (hCG).

PubMed

Klett, Danièle; Meslin, Philippine; Relav, Lauriane; Nguyen, Thi Mong Diep; Mariot, Julie; Jégot, Gwenhaël; Cahoreau, Claire; Combarnous, Yves

2016-10-15

In order to study the intracellular cAMP response kinetics of Leydig cells to hormones with LH activity, we used MLTC-1 cells transiently expressing a chimeric cAMP-responsive luciferase so that real-time variations of intracellular cAMP concentration could be followed using oxiluciferin luminescence produced from catalyzed luciferin oxidation. The potencies of the different LHs and CGs were evaluated using areas under the curves (AUC) of their kinetics over 60 min stimulation. All mammalian LHs and CGs tested were found to stimulate cAMP accumulation in these cells. The reversibility of this stimulation was studied by removing the hormone from the culture medium after 10 min of incubation. The ratios of kinetics AUC after removing or not the hormone were used to evaluate the stimulation reversibility of each hormone. Natural and recombinant hLHs and hCGs were found to exhibit slowly reversible activation compared to pituitary rat, ovine, porcine, camel and equine LHs, serum-derived eCG (PMSG) and recombinant eLH/CGs. Carbohydrate side chains are not involved in this phenomenon since natural and recombinant homologous hormones exhibit the same reversibility rates. It is still unknown whether only one human subunit, α or β, is responsible for this behaviour or whether it is due to a particular feature of the hLH and hCG quaternary structure. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Low concentrations of doxycycline attenuates FasL-induced apoptosis in HeLa cells.

PubMed

Yoon, Jung Mi; Koppula, Sushruta; Huh, Se Jong; Hur, Sun Jin; Kim, Chan Gil

2015-07-24

Doxycycline (DC) has been shown to possess non-antibiotic properties including Fas/Fas Ligand (FasL)-mediated apoptosis against several tumor types in the concentration range of 10-40 µg/mL. However, the effect of DC in apoptotic signaling at much low concentrations was not studied. The present study investigated the attenuation effect of low dose of DC on FasL-induced apoptosis in HeLa cell by the methods of MTT assay, fluorescence microscopy, DNA fragmentation, flow cytometry analysis, and western blotting. In the present findings we showed that low concentration of DC (<2.0 µg/mL) exhibited protective effects against FasL-induced apoptosis in HeLa cells. FasL treatment to HeLa cells resulted in a concentration-dependent induction of cell death, and treatment with low concentrations of DC (0.1-2 µg/mL) significantly (p < 0.001) attenuated the FasL-induced cell death as measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Further, the FasL-induced apoptotic features in HeLa cells, such as morphological changes, DNA fragmentation and cell cycle arrest was also inhibited by DC (0.5 µg/mL). Tetracycline and minocycline also showed similar anti-apoptotic effects but were not significant when compared to DC, tested at same concentrations. Further, DC (0.01-16 µg/mL) did not influence the hydrogen peroxide- or cisplatin-induced intrinsic apoptotic pathway in HeLa cells. Protein analysis using Western blotting confirmed that FasL-induced cleavage/activation of caspase-8 and caspase-3, were inhibited by DC treatment at low concentration (0.5 µg/mL). Considering the overall data, we report for the first time that DC exhibited anti-apoptotic effects at low concentrations in HeLa cells by inhibition of caspase activation via FasL-induced extrinsic pathway.

Feature-Based Attention in Early Vision for the Modulation of Figure–Ground Segregation

PubMed Central

Wagatsuma, Nobuhiko; Oki, Megumi; Sakai, Ko

2013-01-01

We investigated psychophysically whether feature-based attention modulates the perception of figure–ground (F–G) segregation and, based on the results, we investigated computationally the neural mechanisms underlying attention modulation. In the psychophysical experiments, the attention of participants was drawn to a specific motion direction and they were then asked to judge the side of figure in an ambiguous figure with surfaces consisting of distinct motion directions. The results of these experiments showed that the surface consisting of the attended direction of motion was more frequently observed as figure, with a degree comparable to that of spatial attention (Wagatsuma et al., 2008). These experiments also showed that perception was dependent on the distribution of feature contrast, specifically the motion direction differences. These results led us to hypothesize that feature-based attention functions in a framework similar to that of spatial attention. We proposed a V1–V2 model in which feature-based attention modulates the contrast of low-level feature in V1, and this modulation of contrast changes directly the surround modulation of border-ownership-selective cells in V2; thus, perception of F–G is biased. The model exhibited good agreement with human perception in the magnitude of attention modulation and its invariance among stimuli. These results indicate that early-level features that are modified by feature-based attention alter subsequent processing along afferent pathway, and that such modification could even change the perception of object. PMID:23515841

Feature-based attention in early vision for the modulation of figure-ground segregation.

PubMed

Wagatsuma, Nobuhiko; Oki, Megumi; Sakai, Ko

2013-01-01

We investigated psychophysically whether feature-based attention modulates the perception of figure-ground (F-G) segregation and, based on the results, we investigated computationally the neural mechanisms underlying attention modulation. In the psychophysical experiments, the attention of participants was drawn to a specific motion direction and they were then asked to judge the side of figure in an ambiguous figure with surfaces consisting of distinct motion directions. The results of these experiments showed that the surface consisting of the attended direction of motion was more frequently observed as figure, with a degree comparable to that of spatial attention (Wagatsuma et al., 2008). These experiments also showed that perception was dependent on the distribution of feature contrast, specifically the motion direction differences. These results led us to hypothesize that feature-based attention functions in a framework similar to that of spatial attention. We proposed a V1-V2 model in which feature-based attention modulates the contrast of low-level feature in V1, and this modulation of contrast changes directly the surround modulation of border-ownership-selective cells in V2; thus, perception of F-G is biased. The model exhibited good agreement with human perception in the magnitude of attention modulation and its invariance among stimuli. These results indicate that early-level features that are modified by feature-based attention alter subsequent processing along afferent pathway, and that such modification could even change the perception of object.

Pathology and genomics of pediatric melanoma: A critical reexamination and new insights.

PubMed

Bahrami, Armita; Barnhill, Raymond L

2018-02-01

The clinicopathologic features of pediatric melanoma are distinct from those of the adult counterpart. For example, most childhood melanomas exhibit a uniquely favorable biologic behavior, save for those arising in large/giant congenital nevi. Recent studies suggest that the characteristically favorable biologic behavior of childhood melanoma may be related to extreme telomere shortening and dysfunction in the cancer cells. Herein, we review the genomic profiles that have been defined for the different subtypes of pediatric melanoma and particularly emphasize the potential prognostic value of telomerase reverse transcriptase alterations for these tumors. © 2017 Wiley Periodicals, Inc.

Hole growth dynamics in a two dimensional Leidenfrost droplet

NASA Astrophysics Data System (ADS)

Raufaste, Christophe; Celestini, Franck; Barzyk, Alexandre; Frisch, Thomas

2015-03-01

We studied the behaviors of Leidenfrost droplets confined in a Hele-Shaw cell. These droplets are unstable above a critical size and a hole grows at their center. We experimentally investigate two different systems for which the hole growth dynamics exhibits peculiar features that are driven by capillarity and inertia. We report a first regime characterized by the liquid reorganization from a liquid sheet to a liquid torus with similarities to the burst of micron-thick soap films. In the second regime, the liquid torus expands and thins before fragmentation. Finally, we propose models to account for the experimental results.

Laser-induced fluorescence spectroscopy of the secondary cataract

NASA Astrophysics Data System (ADS)

Maslov, N. A.; Larionov, P. M.; Rozhin, I. A.; Druzhinin, I. B.; Chernykh, V. V.

2016-06-01

Excitation-emission matrices of laser-induced fluorescence of lens capsule epithelium, the lens nucleus, and the lens capsule are investigated. A solid-state laser in combination with an optical parametric generator tunable in the range from 210 to 350 nm was used for excitation of fluorescence. The spectra of fluorescence of all three types of tissues exhibit typical features that are specific to them and drastically differ from one another. This effect can be used for intrasurgical control of presence of residual lens capsule epithelium cells in the capsular bag after surgical treatment of a cataract.

Effect of lipopolysaccharide on protein accumulation by murine peritoneal macrophages: the correlation to activation for macrophage tumoricidal function

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

Tannenbaum, C.S.

1987-01-01

The protein synthetic patterns of tumoricidal murine peritoneal macrophage populations have been compared to those of non-tumoricidal populations utilizing two dimensional polyacrylamide gel electrophoresis (2D PAGE) of (/sup 35/S)-methionine-labeled proteins. While the protein synthetic patterns exhibited by resident, inflammatory and activated macrophages had numerous common features which distinguished them from the other normal non-macrophage cell types examined, unique proteins also distinguished each macrophage population from the others. Peritoneal macrophages elicited by treatment with heat killed Propionibacterium acnes, the live, attenuated Mycobacterium bovis strain BCG, Listeria monocytogenes and the protozoan flagellate Trypanosoma rhodesiense, all exhibited tumoricidal activity in 16h or 72hmore » functional assays, and shared a common protein synthetic profile which differentiated them from the synthetic patterns characteristic of the non-tumoricidal resident and inflammatory macrophages.« less

Lymphocytic Mural Folliculitis Resembling Epitheliotropic Lymphoma in Tigers ( Panthera tigris).

PubMed

Sula, Mee-Ja M; Frank, Linda A; Ramsay, Edward C

2018-01-01

A striking form of lymphocytic mural folliculitis is described in 6 tigers ( Panthera tigris). Clinically, all tigers exhibited regionally extensive chronic, variably waxing and waning alopecia with minimal scaling and crusting most pronounced over the head, neck, and shoulders. More severely affected tigers exhibited marked hyperpigmentation and lichenification. Pruritus was not a feature. Tigers generally lacked signs of systemic illness and clinical pathology findings were unremarkable. Histologic examination of skin biopsies revealed infiltrative lymphocytic mural folliculitis extending the length of the hair follicle. Mild epidermal lymphocytic infiltrates were frequent. The surrounding dermis was histologically unremarkable in 4 of 6 tigers or associated with mild perifollicular and periadnexal mixed inflammation in 2 of 6 tigers. The cause of the mural folliculitis was not identified, and tigers responded poorly to immunomodulatory therapy. Lymphocytic mural folliculitis might be a nonspecific hypersensitivity reaction pattern in tigers, and care should be taken to differentiate this reaction pattern from epitheliotropic T-cell lymphoma.

The Progression of Cell Death Affects the Rejection of Allogeneic Tumors in Immune-Competent Mice – Implications for Cancer Therapy

PubMed Central

Chaurio, Ricardo A.; Muñoz, Luis E.; Maueröder, Christian; Janko, Christina; Harrer, Thomas; Fürnrohr, Barbara G.; Niederweis, Michael; Bilyy, Rostyslav; Schett, Georg; Herrmann, Martin; Berens, Christian

2014-01-01

Large amounts of dead and dying cells are produced during cancer therapy and allograft rejection. Depending on the death pathway and stimuli involved, dying cells exhibit diverse features, resulting in defined physiological consequences for the host. It is not fully understood how dying and dead cells modulate the immune response of the host. To address this problem, different death stimuli were studied in B16F10 melanoma cells by regulated inducible transgene expression of the pro-apoptotic active forms of caspase-3 (revCasp-3), Bid (tBid), and the Mycobacterium tuberculosis-necrosis inducing toxin (CpnTCTD). The immune outcome elicited for each death stimulus was assessed by evaluating the allograft rejection of melanoma tumors implanted subcutaneously in BALB/c mice immunized with dying cells. Expression of all proteins efficiently killed cells in vitro (>90%) and displayed distinctive morphological and physiological features as assessed by multiparametric flow cytometry analysis. BALB/c mice immunized with allogeneic dying melanoma cells expressing revCasp-3 or CpnTCTD showed strong rejection of the allogeneic challenge. In contrast, mice immunized with cells dying either after expression of tBid or irradiation with UVB did not, suggesting an immunologically silent cell death. Surprisingly, immunogenic cell death induced by expression of revCasp-3 or CpnTCTD correlated with elevated intracellular reactive oxygen species (ROS) levels at the time point of immunization. Conversely, early mitochondrial dysfunction induced by tBid expression or UVB irradiation accounted for the absence of intracellular ROS accumulation at the time point of immunization. Although ROS inhibition in vitro was not sufficient to abrogate the immunogenicity in our allo-immunization model, we suggest that the point of ROS generation and its intracellular accumulation may be an important factor for its role as damage associated molecular pattern in the development of allogeneic responses. PMID:25426116

Overexpression of hypoxia-inducible factor 1 alpha improves immunomodulation by dental mesenchymal stem cells.

PubMed

Martinez, Victor G; Ontoria-Oviedo, Imelda; Ricardo, Carolina P; Harding, Sian E; Sacedon, Rosa; Varas, Alberto; Zapata, Agustin; Sepulveda, Pilar; Vicente, Angeles

2017-09-29

Human dental mesenchymal stem cells (MSCs) are considered as highly accessible and attractive MSCs for use in regenerative medicine, yet some of their features are not as well characterized as other MSCs. Hypoxia-preconditioning and hypoxia-inducible factor 1 (HIF-1) alpha overexpression significantly improves MSC therapeutics, but the mechanisms involved are not fully understood. In the present study, we characterize immunomodulatory properties of dental MSCs and determine changes in their ability to modulate adaptive and innate immune populations after HIF-1 alpha overexpression. Human dental MSCs were stably transduced with green fluorescent protein (GFP-MSCs) or GFP-HIF-1 alpha lentivirus vectors (HIF-MSCs). A hypoxic-like metabolic profile was confirmed by mitochondrial and glycolysis stress test. Capacity of HIF-MSCs to modulate T-cell activation, dendritic cell differentiation, monocyte migration, and polarizations towards macrophages and natural killer (NK) cell lytic activity was assessed by a number of functional assays in co-cultures. The expression of relevant factors were determined by polymerase chain reaction (PCR) analysis and enzyme-linked immunosorbent assay (ELISA). While HIF-1 alpha overexpression did not modify the inhibition of T-cell activation by MSCs, HIF-MSCs impaired dendritic cell differentiation more efficiently. In addition, HIF-MSCs showed a tendency to induce higher attraction of monocytes, which differentiate into suppressor macrophages, and exhibited enhanced resistance to NK cell-mediated lysis, which supports the improved therapeutic capacity of HIF-MSCs. HIF-MSCs also displayed a pro-angiogenic profile characterized by increased expression of CXCL12/SDF1 and CCL5/RANTES and complete loss of CXCL10/IP10 transcription. Immunomodulation and expression of trophic factors by dental MSCs make them perfect candidates for cell therapy. Overexpression of HIF-1 alpha enhances these features and increases their resistance to allogenic NK cell lysis and, hence, their potential in vivo lifespan. Our results further support the use of HIF-1 alpha-expressing dental MSCs for cell therapy in tissue injury and immune disorders.

Seed morphology and variation in the genus Pachycereus (Cactaceae).

PubMed

Arias, Salvador; Terrazas, Teresa

2004-08-01

Seeds of 13 Pachycereus species and two Stenocereus species that have been suggested as closely related were examined with the scanning electron microscope. Quantitative features were evaluated using multivariate analysis in order to identify characters that distinguish them. Several species groups were recognized on the basis of 16 qualitative characters. All species studied are keeled. Stenocereus aragonii and S. eichlamii share with most Pachycereus species large size, glossy appearance, and a flat relief on periclinal cells in the lateral region. Pachycereus gatesii and P. schottii are unique in having the smallest seeds and a deeply impressed hilum-micropylar region. P. hollianus does not exhibit micro-relief on periclinal walls in the lateral region, and P. fulviceps has no expanded testa border. Multivariate analysis showed that four characters, length, breadth, hilum-micropylar region length, and angle, made the greatest contribution to distinguishing among species groups. More than 80% of P. fulviceps, P. hollianus, P. tepamo, P. weberi, and S. eichlamii seeds could be classified correctly using four seed features and the percentage was even higher using just two or three features for P. gatesii, P. grandis, P. militaris, P. pringlei, and P. schottii. Testa appearance, testa cell-pattern, and position relative to the rim of the hilum-micropylar region were found to be potentially informative and should be combined with other sources of data in future phylogenetic analyses.

Metabolic imaging of tumor for diagnosis and response for therapy

NASA Astrophysics Data System (ADS)

Zagaynova, Elena; Shirmanova, Marina; Lukina, Maria; Dudenkova, Varvara; Ignatova, Nadezgda; Elagin, Vadim; Shlivko, Irena; Scheslavsky, Vladislav; Orlinskay, Natalia

2018-02-01

Nonlinear optical microscopy combined with fluorescence lifetime imaging is a non-invasive imaging technique, based on the study of fluorescence decay times of naturally occurring fluorescent molecules, enabling a noninvasive investigation of the biological tissue with subcellular resolution. Cancer exhibits altered cellular metabolism, which affects the autofluorescence of metabolic cofactors NAD(P)H and FAD. In this study features of tumor metabolism in different systems of organization (from cell culture to patient lesion) was showed. The observed differences in the relative contributions of free NAD(P)H and FAD testify to an increased a glycolytic metabolism in cancer cells compare to fibroblasts. In 3D spheroids, the cells of the proliferating zone had greater a1 and lower tm values than the cells of the quiescent zone, which likely is a consequence of their higher glycolytic rate. During the growth of colorectal cancer in the experimental mouse model, the contribution of the free component of NAD(P)H was increased. Dysplastic nevus and melanoma is characterized by raised contribution of free NADH compare to healthy skin. Therefore, melanoma cells had very short value of τ1.

Extranodal rosai-dorfman disease associated with increased numbers of immunoglobulin g4 plasma cells involving the colon: case report with literature review.

PubMed

Wimmer, Daniel B; Ro, Jae Y; Lewis, Annisa; Schwartz, Mary R; Caplan, Richard; Schwarz, Peter; Ayala, Alberto G

2013-07-01

A 49-year-old woman presented with fever, weight loss, night sweats, hematochezia, and acid reflux symptoms. Two large, firm cecal lesions were seen at colonoscopy, but multiple biopsies were inconclusive. The patient underwent a right hemicolectomy for a clinical diagnosis of colon cancer. Noncaseating granulomatous inflammation with background lymphocytes, plasma cells, and histiocytes exhibiting emperipolesis were identified. With these histologic features and immunoreactivity for S-100 protein and CD68, a diagnosis of Rosai-Dorfman disease was rendered. Other areas had storiform fibrosis admixed with numerous immunoglobulin G4 (IgG4)-positive plasma cells. Although a few preliminary reports have noted an increased number of IgG4-positive plasma cells in Rosai-Dorfman disease, the relationship between these 2 conditions is unclear. To our knowledge, this is the first case report of a possible association of colonic Rosai-Dorfman disease with an increased number of IgG4-positive plasma cells. Reviews of colonic Rosai-Dorfman disease and IgG4-related sclerosis are presented to heighten awareness of this rare presentation.

Semi-transparent solar cells

NASA Astrophysics Data System (ADS)

Sun, J.; Jasieniak, J. J.

2017-03-01

Semi-transparent solar cells are a type of technology that combines the benefits of visible light transparency and light-to-electricity conversion. One of the biggest opportunities for such technologies is in their integration as windows and skylights within energy-sustainable buildings. Currently, such building integrated photovoltaics (BIPV) are dominated by crystalline silicon based modules; however, the opaque nature of silicon creates a unique opportunity for the adoption of emerging photovoltaic candidates that can be made truly semi-transparent. These include: amorphous silicon-, kesterite-, chalcopyrite-, CdTe-, dye-sensitized-, organic- and perovskite- based systems. For the most part, amorphous silicon has been the workhorse in the semi-transparent solar cell field owing to its established, low-temperature fabrication processes. Excitement around alternative classes, particularly perovskites and the inorganic candidates, has recently arisen because of the major efficiency gains exhibited by these technologies. Importantly, each of these presents unique opportunities and challenges within the context of BIPV. This topic review provides an overview into the broader benefits of semi-transparent solar cells as building-integrated features, as well as providing the current development status into all of the major types of semi-transparent solar cells technologies.

Design checkpoint kinase 2 inhibitors by pharmacophore modeling and virtual screening techniques.

PubMed

Wang, Yen-Ling; Lin, Chun-Yuan; Shih, Kuei-Chung; Huang, Jui-Wen; Tang, Chuan-Yi

2013-12-01

Damage to DNA is caused by ionizing radiation, genotoxic chemicals or collapsed replication forks. When DNA is damaged or cells fail to respond, a mutation that is associated with breast or ovarian cancer may occur. Mammalian cells control and stabilize the genome using a cell cycle checkpoint to prevent damage to DNA or to repair damaged DNA. Checkpoint kinase 2 (Chk2) is one of the important kinases, which strongly affects DNA-damage and plays an important role in the response to the breakage of DNA double-strands and related lesions. Therefore, this study concerns Chk2. Its purpose is to find potential inhibitors using the pharmacophore hypotheses (PhModels) and virtual screening techniques. PhModels can identify inhibitors with high biological activities and virtual screening techniques are used to screen the database of the National Cancer Institute (NCI) to retrieve compounds that exhibit all of the pharmacophoric features of potential inhibitors with high interaction energy. Ten PhModels were generated using the HypoGen best algorithm. The established PhModel, Hypo01, was evaluated by performing a cost function analysis of its correlation coefficient (r), root mean square deviation (RMSD), cost difference, and configuration cost, with the values 0.955, 1.28, 192.51, and 16.07, respectively. The result of Fischer's cross-validation test for the Hypo01 model yielded a 95% confidence level, and the correlation coefficient of the testing set (rtest) had a best value of 0.81. The potential inhibitors were then chosen from the NCI database by Hypo01 model screening and molecular docking using the cdocker docking program. Finally, the selected compounds exhibited the identified pharmacophoric features and had a high interaction energy between the ligand and the receptor. Eighty-three potential inhibitors for Chk2 are retrieved for further study. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development and characterization of a 3D multicell microtissue culture model of airway smooth muscle.

PubMed

West, Adrian R; Zaman, Nishat; Cole, Darren J; Walker, Matthew J; Legant, Wesley R; Boudou, Thomas; Chen, Christopher S; Favreau, John T; Gaudette, Glenn R; Cowley, Elizabeth A; Maksym, Geoffrey N

2013-01-01

Airway smooth muscle (ASM) cellular and molecular biology is typically studied with single-cell cultures grown on flat 2D substrates. However, cells in vivo exist as part of complex 3D structures, and it is well established in other cell types that altering substrate geometry exerts potent effects on phenotype and function. These factors may be especially relevant to asthma, a disease characterized by structural remodeling of the airway wall, and highlights a need for more physiologically relevant models of ASM function. We utilized a tissue engineering platform known as microfabricated tissue gauges to develop a 3D culture model of ASM featuring arrays of ∼0.4 mm long, ∼350 cell "microtissues" capable of simultaneous contractile force measurement and cell-level microscopy. ASM-only microtissues generated baseline tension, exhibited strong cellular organization, and developed actin stress fibers, but lost structural integrity and dissociated from the cantilevers within 3 days. Addition of 3T3-fibroblasts dramatically improved survival times without affecting tension development or morphology. ASM-3T3 microtissues contracted similarly to ex vivo ASM, exhibiting reproducible responses to a range of contractile and relaxant agents. Compared with 2D cultures, microtissues demonstrated identical responses to acetylcholine and KCl, but not histamine, forskolin, or cytochalasin D, suggesting that contractility is regulated by substrate geometry. Microtissues represent a novel model for studying ASM, incorporating a physiological 3D structure, realistic mechanical environment, coculture of multiple cells types, and comparable contractile properties to existing models. This new model allows for rapid screening of biochemical and mechanical factors to provide insight into ASM dysfunction in asthma.

A novel 3D human glioblastoma cell culture system for modeling drug and radiation responses

PubMed Central

Stevenson, Katrina; Gilmour, Lesley; Hamilton, Graham; Chalmers, Anthony J

2017-01-01

Abstract Background. Glioblastoma (GBM) is the most common primary brain tumor, with dismal prognosis. The failure of drug–radiation combinations with promising preclinical data to translate into effective clinical treatments may relate to the use of simplified 2-dimensional in vitro GBM cultures. Methods. We developed a customized 3D GBM culture system based on a polystyrene scaffold (Alvetex) that recapitulates key histological features of GBM and compared it with conventional 2D cultures with respect to their response to radiation and to molecular targeted agents for which clinical data are available. Results. In 3 patient-derived GBM lines, no difference in radiation sensitivity was observed between 2D and 3D cultures, as measured by clonogenic survival. Three different molecular targeted agents, for which robust clinical data are available were evaluated in 2D and 3D conditions: (i) temozolomide, which improves overall survival and is standard of care for GBM, exhibited statistically significant effects on clonogenic survival in both patient-derived cell lines when evaluated in the 3D model compared with only one cell line in 2D cells; (ii) bevacizumab, which has been shown to increase progression-free survival when added to standard chemoradiation in phase III clinical trials, exhibited marked radiosensitizing activity in our 3D model but had no effect on 2D cells; and (iii) erlotinib, which had no efficacy in clinical trials, displayed no activity in our 3D GBM model, but radiosensitized 2D cells. Conclusions. Our 3D model reliably predicted clinical efficacy, strongly supporting its clinical relevance and potential value in preclinical evaluation of drug–radiation combinations for GBM. PMID:27576873

Identifying mechanisms for superdiffusive dynamics in cell trajectories

NASA Astrophysics Data System (ADS)

Passucci, Giuseppe; Brasch, Megan; Henderson, James; Manning, M. Lisa

Self-propelled particle (SPP) models have been used to explore features of active matter such as motility-induced phase separation, jamming, and flocking, and are often used to model biological cells. However, many cells exhibit super-diffusive trajectories, where displacements scale faster than t 1 / 2 in all directions, and these are not captured by traditional SPP models. We extract cell trajectories from image stacks of mouse fibroblast cells moving on 2D substrates and find super-diffusive mean-squared displacements in all directions across varying densities. Two SPP model modifications have been proposed to capture super-diffusive dynamics: Levy walks and heterogeneous motility parameters. In mouse fibroblast cells displacement probability distributions collapse when time is rescaled by a power greater than 1/2, which is consistent with Levy walks. We show that a simple SPP model with heterogeneous rotational noise can also generate a similar collapse. Furthermore, a close examination of statistics extracted directly from cell trajectories is consistent with a heterogeneous mobility SPP model and inconsistent with a Levy walk model. Our work demonstrates that a simple set of analyses can distinguish between mechanisms for anomalous diffusion in active matter.

Preclinical Corrective Gene Transfer in Xeroderma Pigmentosum Human Skin Stem Cells

PubMed Central

Warrick, Emilie; Garcia, Marta; Chagnoleau, Corinne; Chevallier, Odile; Bergoglio, Valérie; Sartori, Daniela; Mavilio, Fulvio; Angulo, Jaime F; Avril, Marie-Françoise; Sarasin, Alain; Larcher, Fernando; Del Rio, Marcela; Bernerd, Françoise; Magnaldo, Thierry

2012-01-01

Xeroderma pigmentosum (XP) is a devastating disease associated with dramatic skin cancer proneness. XP cells are deficient in nucleotide excision repair (NER) of bulky DNA adducts including ultraviolet (UV)-induced mutagenic lesions. Approaches of corrective gene transfer in NER-deficient keratinocyte stem cells hold great hope for the long-term treatment of XP patients. To face this challenge, we developed a retrovirus-based strategy to safely transduce the wild-type XPC gene into clonogenic human primary XP-C keratinocytes. De novo expression of XPC was maintained in both mass population and derived independent candidate stem cells (holoclones) after more than 130 population doublings (PD) in culture upon serial propagation (>1040 cells). Analyses of retrovirus integration sequences in isolated keratinocyte stem cells suggested the absence of adverse effects such as oncogenic activation or clonal expansion. Furthermore, corrected XP-C keratinocytes exhibited full NER capacity as well as normal features of epidermal differentiation in both organotypic skin cultures and in a preclinical murine model of human skin regeneration in vivo. The achievement of a long-term genetic correction of XP-C epidermal stem cells constitutes the first preclinical model of ex vivo gene therapy for XP-C patients. PMID:22068429

Bone formation in vitro and in nude mice by human osteosarcoma cells.

PubMed

Ogose, A; Motoyama, T; Hotta, T; Watanabe, H; Takahashi, H E

1995-01-01

Osteosarcomas contain variable amounts of bony tissue, but the mechanism of bone formation by osteosarcoma is not well understood. While a number of cultured human osteosarcoma cell lines have been established, they are maintained by different media and differ qualitatively with regard to bone formation. We examined different media for their ability to support bone formation in vitro and found the alpha-modification of Eagle's minimal essential medium supplemented with beta glycerophosphate was best for this purpose, because it contained the proper calcium and phosphate concentrations. Subsequently, we compared seven human osteosarcoma cell lines under the same experimental conditions to clarify their ability to induce bone formation. NOS-1 cells most frequently exhibited features of bone formation in vitro and in nude mice. Collagen synthesis by tumour cells themselves seemed to be the most important factor for bone volume. However, even HuO9 cells, which lacked collagen synthesis and failed to form bone in vitro, successfully formed tumours containing bone in nude mice. Histological analysis of HuO9 cells in diffusion chambers implanted in nude mice and the findings of polymerase chain reaction indicated that the phenomenon was probably due to bone morphogenetic protein.

Unique Aspects of Cryptochrome in Chronobiology and Metabolism, Pancreatic β-Cell Dysfunction, and Regeneration: Research into Cysteine414-Alanine Mutant CRY1.

PubMed

Okano, Satoshi

2016-01-01

Cryptochrome proteins (CRYs), which can bind noncovalently to cofactor (chromophore) flavin adenine dinucleotide (FAD), occur widely among organisms. CRYs play indispensable roles in the generation of circadian rhythm in mammals. Transgenic mice (Tg mice), ubiquitously expressing mouse CRY1 having a mutation in which cysteine414 (the zinc-binding site of CRY1) being replaced with alanine, display unique phenotypes in their circadian rhythms. Moreover, male Tg mice exhibit symptoms of diabetes characterized by beta-cell dysfunction, resembling human maturity onset diabetes of the young (MODY). The lowered proliferation of β -cells is a primary cause of age-dependent β -cell loss. Furthermore, unusually enlarged duct-like structures developed prominently in the Tg mice pancreases. The duct-like structures contained insulin-positive cells, suggesting neogenesis of β -cells in the Tg mice. This review, based mainly on the author's investigation of the unique features of Tg mice, presents reported results and recent findings related to molecular processes associated with mammalian cryptochromes, especially their involvement in the regulation of metabolism. New information is described with emphasis on the aspects of islet architecture, pancreatic β -cell dysfunction, and regeneration.

Eugenol and its structural analogs inhibit monoamine oxidase A and exhibit antidepressant-like activity.

PubMed

Tao, Guoxin; Irie, Yoshifumi; Li, Dian-Jun; Keung, Wing Ming

2005-08-01

Eugenol (1) is an active principle of Rhizoma acori graminei, a medicinal herb used in Asia for the treatment of symptoms reminiscent of Alzheimer's disease (AD). It has been shown to protect neuronal cells from the cytotoxic effect of amyloid beta peptides (Abetas) in cell cultures and exhibit antidepressant-like activity in mice. Results from this study show that eugenol inhibits monoamine oxidase A (MAOA) preferentially with a K(i)=26 microM. It also inhibits MAOB but at much higher concentrations (K(i)=211 microM). In both cases, inhibition is competitive with respect to the monoamine substrate. Survey of compounds structurally related to eugenol has identified a few that inhibit MAOs more potently. Structure activity relationship reveals structural features important for MAOA and MAOB inhibition. Molecular docking experiments were performed to help explain the SAR outcomes. Four of these compounds, two (1, 24) inhibiting MAOA selectively and the other two (19, 21) inhibiting neither MAOA nor MAOB, were tested for antidepressant-like activity using the forced swim test in mice. Results suggest a potential link between the antidepressant activity of eugenol and its MAOA inhibitory activity.

Dclk1+ small intestinal epithelial tuft cells display the hallmarks of quiescence and self-renewal

PubMed Central

Chandrakesan, Parthasarathy; May, Randal; Qu, Dongfeng; Weygant, Nathaniel; Taylor, Vivian E.; Li, James D.; Ali, Naushad; Sureban, Sripathi M.; Qante, Michael; Wang, Timothy C.; Bronze, Michael S.; Houchen, Courtney W.

2015-01-01

To date, no discrete genetic signature has been defined for isolated Dclk1+ tuft cells within the small intestine. Furthermore, recent reports on the functional significance of Dclk1+ cells in the small intestine have been inconsistent. These cells have been proposed to be fully differentiated cells, reserve stem cells, and tumor stem cells. In order to elucidate the potential function of Dclk1+ cells, we FACS-sorted Dclk1+ cells from mouse small intestinal epithelium using transgenic mice expressing YFP under the control of the Dclk1 promoter (Dclk1-CreER;Rosa26-YFP). Analysis of sorted YFP+ cells demonstrated marked enrichment (~6000 fold) for Dclk1 mRNA compared with YFP− cells. Dclk1+ population display ~6 fold enrichment for the putative quiescent stem cell marker Bmi1. We observed significantly greater expression of pluripotency genes, pro-survival genes, and quiescence markers in the Dclk1+ population. A significant increase in self-renewal capability (14-fold) was observed in in vitro isolated Dclk1+ cells. The unique genetic report presented in this manuscript suggests that Dclk1+ cells may maintain quiescence, pluripotency, and metabolic activity for survival/longevity. Functionally, these reserve characteristics manifest in vitro, with Dclk1+ cells exhibiting greater ability to self-renew. These findings indicate that quiescent stem-like functionality is a feature of Dclk1-expressing tuft cells. PMID:26362399

Recognition of extremophilic archaeal viruses by eukaryotic cells: a promising nanoplatform from the third domain of life

PubMed Central

Uldahl, Kristine Buch; Wu, Linping; Hall, Arnaldur; Papathanasiou, Pavlos; Peng, Xu; Moghimi, Seyed Moein

2016-01-01

Viruses from the third domain of life, Archaea, exhibit unusual features including extreme stability that allow their survival in harsh environments. In addition, these species have never been reported to integrate into human or any other eukaryotic genomes, and could thus serve for exploration of novel medical nanoplatforms. Here, we selected two archaeal viruses Sulfolobus monocaudavirus 1 (SMV1) and Sulfolobus spindle shaped virus 2 (SSV2) owing to their unique spindle shape, hyperthermostable and acid-resistant nature and studied their interaction with mammalian cells. Accordingly, we followed viral uptake, intracellular trafficking and cell viability in human endothelial cells of brain (hCMEC/D3 cells) and umbilical vein (HUVEC) origin. Whereas SMV1 is efficiently internalized into both types of human cells, SSV2 differentiates between HUVECs and hCMEC/D3 cells, thus opening a path for selective cell targeting. On internalization, both viruses localize to the lysosomal compartments. Neither SMV1, nor SSV2 induced any detrimental effect on cell morphology, plasma membrane and mitochondrial functionality. This is the first study demonstrating recognition of archaeal viruses by eukaryotic cells which provides good basis for future exploration of archaeal viruses in bioengineering and development of multifunctional vectors. PMID:27892499

Clinicopathological characteristics of primary gastric T-cell lymphoma.

PubMed

Kawamoto, Kenichiro; Nakamura, Shotaro; Iwashita, Akinori; Watanabe, Jiro; Oshiro, Yumi; Nakayama, Yoshifuku; Nimura, Satoshi; Kimura, Nobuhiro; Aoyagi, Kunihiko; Yao, Takashi; Kuramochi, Shigeru; Matsuyama, Atsuji; Kurihara, Kenji; Ohshima, Koichi; Takeshita, Morishige

2009-12-01

To investigate the clinicopathological characteristics of 20 primary gastric T-cell lymphoma (GTCL) cases without human T-lymphotropic virus type I infection in Japan, a non-endemic area for coeliac disease. Fifteen cases had no history of persistent diarrhoea or severe hypoproteinaemia. Histologically, 13 cases (65%) consisted of large cell lymphoma and seven (35%) were of medium-sized cells. Intraepithelial lymphoma cell invasion was found in three cases (15%). Two of 10 surgical cases (20%) showed intramucosal tumour cell spreading with enteropathy-like features. Helicobacter pylori CagA gene was detected in three of 10 cases (30%). The lymphoma cells of all 20 cases were positive for CD3 and/or TCRbetaF1 and negative for CD56. CD4- and CD8- lymphoma was found in 11 cases (55%), CD4+ lymphoma in seven (35%) and CD8+ lymphoma in two (10%). CD30+, CD5+ and CD25+ lymphomas were detected in nine (45%), 10 (50%) and 11 (55%) cases, respectively. Five-year survival of the 16 available cases was 54%. Early clinical stage and medium-sized cell lymphoma were significantly (P < 0.05) better prognostic factors. Patients with GTCL exhibit distinct clinicopathological findings and prognoses from those with enteropathy-associated T-cell lymphomas. GTCL may be mainly derived from lamina propria and parafollicular T cells.

Effect of human cell malignancy on activity of DNA polymerase iota.

PubMed

Kazakov, A A; Grishina, E E; Tarantul, V Z; Gening, L V

2010-07-01

An increased level of mutagenesis, partially caused by imbalanced activities of error prone DNA polymerases, is a key symptom of cell malignancy. To clarify the possible role of incorrect DNA polymerase iota (Pol iota) function in increased frequency of mutations in mammalian cells, the activity of this enzyme in extracts of cells of different mouse organs and human eye (melanoma) and eyelid (basal-cell skin carcinoma) tumor cells was studied. Both Mg2+, considered as the main activator of the enzyme reaction of in vivo DNA replication, and Mn2+, that activates homogeneous Pol iota preparations in experiments in vitro more efficiently compared to all other bivalent cations, were used as cofactors of the DNA polymerase reaction in these experiments. In the presence of Mg2+, the enzyme was active only in cell extracts of mouse testicles and brain, whereas in the presence of Mn2+ the activity of Pol iota was found in all studied normal mouse organs. It was found that in cell extracts of both types of malignant tumors (basal-cell carcinoma and melanoma) Pol iota activity was observed in the presence of either Mn2+ or Mg2+. Manganese ions activated Pol iota in both cases, though to a different extent. In the presence of Mn2+ the Pol iota activity in the basal-cell carcinoma exceeded 2.5-fold that in control cells (benign tumors from the same eyelid region). In extracts of melanoma cells in the presence of either cation, the level of the enzyme activity was approximately equal to that in extracts of cells of surrounding tumor-free tissues as well as in eyes removed after traumas. The distinctive feature of tissue malignancy (in basal-cell carcinoma and in melanoma) was the change in DNA synthesis revealed as Mn2+-activated continuation of DNA synthesis after incorrect incorporation of dG opposite dT in the template by Pol iota. Among cell extracts of different normal mouse organs, only those of testicles exhibited a similar feature. This similarity can be explained by cell division blocking that occurs in all normal cells except in testicles and in malignant cells.

Global loss of a nuclear lamina component, lamin A/C, and LINC complex components SUN1, SUN2, and nesprin-2 in breast cancer.

PubMed

Matsumoto, Ayaka; Hieda, Miki; Yokoyama, Yuhki; Nishioka, Yu; Yoshidome, Katsuhide; Tsujimoto, Masahiko; Matsuura, Nariaki

2015-10-01

Cancer cells exhibit a variety of features indicative of atypical nuclei. However, the molecular mechanisms underlying these phenomena remain to be elucidated. The linker of nucleoskeleton and cytoskeleton (LINC) complex, a nuclear envelope protein complex consisting mainly of the SUN and nesprin proteins, connects nuclear lamina and cytoskeletal filaments and helps to regulate the size and shape of the nucleus. Using immunohistology, we found that a nuclear lamina component, lamin A/C and all of the investigated LINC complex components, SUN1, SUN2, and nesprin-2, were downregulated in human breast cancer tissues. In the majority of cases, we observed lower expression levels of these analytes in samples' cancerous regions as compared to their cancer-associated noncancerous regions (in cancerous regions, percentage of tissue samples exhibiting low protein expression: lamin A/C, 85% [n = 73]; SUN1, 88% [n = 43]; SUN2, 74% [n = 43]; and nesprin-2, 79% [n = 53]). Statistical analysis showed that the frequencies of recurrence and HER2 expression were negatively correlated with lamin A/C expression (P < 0.05), and intrinsic subtype and ki-67 level were associated with nesprin-2 expression (P < 0.05). In addition, combinatorial analysis using the above four parameters showed that all patients exhibited reduced expression of at least one of four components despite the tumor's pathological classification. Furthermore, several cultured breast cancer cell lines expressed less SUN1, SUN2, nesprin-2 mRNA, and lamin A/C compared to noncancerous mammary gland cells. Together, these results suggest that the strongly reduced expression of LINC complex and nuclear lamina components may play fundamental pathological functions in breast cancer progression. © 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Aurora-A-Dependent Control of TACC3 Influences the Rate of Mitotic Spindle Assembly

PubMed Central

Joseph, Nimesh; Cavazza, Tommaso; Vernos, Isabelle; Pfuhl, Mark; Gergely, Fanni; Bayliss, Richard

2015-01-01

The essential mammalian gene TACC3 is frequently mutated and amplified in cancers and its fusion products exhibit oncogenic activity in glioblastomas. TACC3 functions in mitotic spindle assembly and chromosome segregation. In particular, phosphorylation on S558 by the mitotic kinase, Aurora-A, promotes spindle recruitment of TACC3 and triggers the formation of a complex with ch-TOG-clathrin that crosslinks and stabilises kinetochore microtubules. Here we map the Aurora-A-binding interface in TACC3 and show that TACC3 potently activates Aurora-A through a domain centered on F525. Vertebrate cells carrying homozygous F525A mutation in the endogenous TACC3 loci exhibit defects in TACC3 function, namely perturbed localization, reduced phosphorylation and weakened interaction with clathrin. The most striking feature of the F525A cells however is a marked shortening of mitosis, at least in part due to rapid spindle assembly. F525A cells do not exhibit chromosome missegregation, indicating that they undergo fast yet apparently faithful mitosis. By contrast, mutating the phosphorylation site S558 to alanine in TACC3 causes aneuploidy without a significant change in mitotic duration. Our work has therefore defined a regulatory role for the Aurora-A-TACC3 interaction beyond the act of phosphorylation at S558. We propose that the regulatory relationship between Aurora-A and TACC3 enables the transition from the microtubule-polymerase activity of TACC3-ch-TOG to the microtubule-crosslinking activity of TACC3-ch-TOG-clathrin complexes as mitosis progresses. Aurora-A-dependent control of TACC3 could determine the balance between these activities, thereby influencing not only spindle length and stability but also the speed of spindle formation with vital consequences for chromosome alignment and segregation. PMID:26134678

Structural organization of parallel information processing within the tectofugal visual system of the pigeon.

PubMed

Hellmann, B; Güntürkün, O

2001-01-01

Visual information processing within the ascending tectofugal pathway to the forebrain undergoes essential rearrangements between the mesencephalic tectum opticum and the diencephalic nucleus rotundus of birds. The outer tectal layers constitute a two-dimensional map of the visual surrounding, whereas nucleus rotundus is characterized by functional domains in which different visual features such as movement, color, or luminance are processed in parallel. Morphologic correlates of this reorganization were investigated by means of focal injections of the neuronal tracer choleratoxin subunit B into different regions of the nuclei rotundus and triangularis of the pigeon. Dependent on the thalamic injection site, variations in the retrograde labeling pattern of ascending tectal efferents were observed. All rotundal projecting neurons were located within the deep tectal layer 13. Five different cell populations were distinguished that could be differentiated according to their dendritic ramifications within different retinorecipient laminae and their axons projecting to different subcomponents of the nucleus rotundus. Because retinorecipient tectal layers differ in their input from distinct classes of retinal ganglion cells, each tectorotundal cell type probably processes different aspects of the visual surrounding. Therefore, the differential input/output connections of the five tectorotundal cell groups might constitute the structural basis for spatially segregated parallel information processing of different stimulus aspects within the tectofugal visual system. Because two of five rotundal projecting cell groups additionally exhibited quantitative shifts along the dorsoventral extension of the tectum, data also indicate visual field-dependent alterations in information processing for particular visual features. Copyright 2001 Wiley-Liss, Inc.

Pharmacological features of osthole.

PubMed

Jarząb, Agata; Grabarska, Aneta; Skalicka-Woźniak, Krystyna; Stepulak, Andrzej

2017-05-15

Coumarins are a group of naturally occurring compounds common in the plant world. These substances and their derivatives exhibit a broad range of biological activities. One of the naturally occurring coumarins is osthole, which can most frequently be found in plants of the Apiaceae family. Cnidium monnieri (L.) Cusson ex Juss. Angelica pubescens Maxim. and Peucedanum ostruthium (L.). It has anti-proliferative, anti-inflammatory, anti-convulsant, and antiallergic properties; apart from that, inhibition of platelet aggregation has also been proved. The impact of osthole on bone metabolism has been demonstrated; also its hepatoprotective and neuroprotective properties have been confirmed. The inhibitory effect of this metokcompound on the development of neurodegenerative diseases has been proved in experimental models. Anticancer features of osthole have been also demonstrated both in vitro on different cell lines, and in vivo using animals xenografts. Osthole inhibited proliferation, motility and invasiveness of tumor cells, which may be associated with the induction of apoptosis and cell cycle slowdown. The exact molecular mechanism of osthole anti-cancer mode of action has not been fully elucidated. A synergistic effect of osthole with other anti-tumor substances has been also reported. Modification of its chemical structure led to the synthesis of many derivatives with significant anticancer effects. To sum up, osthole is an interesting therapeutic option, due to both its direct effect on tumor cells, as well as its neuroprotective or anti-inflammatory properties. Thus, there is a chance to use osthole or its synthetic derivatives in the treatment of cancer.

Dermatoscopy-guided therapy of pigmented basal cell carcinoma with imiquimod*

PubMed Central

Husein-ElAhmed, Husein; Fernandez-Pugnaire, Maria Antonia

2016-01-01

BACKGROUND Dermatoscopy is a non-invasive diagnostic tool used to examine skin lesions with an optical magnification. It has been suggested as a useful tool for monitoring therapeutic response in lentigo maligna patients treated with imiquimod. OBJECTIVE To examine the accuracy of dermatoscopy as a tool to monitor the therapeutic response of pigmented basal cell carcinoma treated with imiquimod. METHOD The authors designed a prospective study. Patients with pigmented basal cell carcinoma were included and data regarding the dermatoscopy features were collected following the Menzies criteria, prior to initiating the imiquimod treatment. Subsequent dermatoscopic evaluations were performed at weeks 4 and 8, following imiquimod discontinuation. RESULTS Twenty lesions were included. The most common pigmented dermatoscopy features were large blue-grey ovoid nests (80%), followed by blue-grey globules (50%) and leaf-like areas (30%). No spoke wheel areas were observed. In 17 out of 20 patients, a response was noted during the first evaluation at 4 weeks, while the clearance was noted at the second check-up after 8 weeks. In two patients, the clearance was found at the initial evaluation at 4 weeks, while in one patient, the response remained unchanged. Blue-grey globules were the fastest to exhibit clearance (50% at week 4), followed by leaf-like areas (15%) and large blue-grey ovoid nests (6.25%). CONCLUSION According to our results, dermatoscopic evaluation enhances the accuracy in the assessment of the clinical response to imiquimod in pigmented basal cell carcinoma. PMID:28099598

Anion exchange membrane crosslinked in the easiest way stands out for fuel cells

NASA Astrophysics Data System (ADS)

Hossain, Md. Masem; Wu, Liang; Liang, Xian; Yang, Zhengjin; Hou, Jianqiu; Xu, Tongwen

2018-06-01

Covalent crosslinking is an effective method to stabilize anion exchange membranes (AEMs) against water swelling and high alkaline environment, yet complicated process is required. We report herein a straightforward approach to prepare highly crosslinked, transparent and flexible AEM by simply immersing a halo-alkylated polymer (e.g., brominated poly-(2,6-dimethyl-phenylene oxide)) based membrane in aqueous dimethylamine solution at room temperature and the following methylation. During this crosslinking process, a robust self-crosslinking network is formed which shows a gel fraction in N-methyl-2-pyrrolidone of (up to) 94%. Self-crosslinked membranes show low water uptakes (20-42%) and dimensional swelling (9-16%) compared to non-crosslinked membrane but good hydroxide conductivities (up to 26 mS cm-1) at room temperature. Besides, the resulting membranes show some interesting features: the membranes do not immensely change its room temperature water swelling properties at high temperature but exhibits good hydroxide conductivities (up to 60 mS cm-1 at 80 °C). Noting that, the self-crosslinked AEM reported here has no β-hydrogens, exhibiting extremely high alkaline stability (no decline in hydroxide conductivity in 1 M KOH at 60 °C for 360h). Membrane electrode assembly consists of fabricated membrane shows moderate fuel cell performance reaching peak power density 31 mW cm-2 at 60 °C in a H2/O2 alkaline fuel cell.

Pyramidal neurons in the septal and temporal CA1 field of the human and hedgehog tenrec hippocampus.

PubMed

Liagkouras, Ioannis; Michaloudi, Helen; Batzios, Christos; Psaroulis, Dimitrios; Georgiadis, Marios; Künzle, Heinz; Papadopoulos, Georgios C

2008-07-07

The present study examines comparatively the cellular density of disector-counted/Nissl-stained CA1 pyramidal neurons and the morphometric characteristics (dendritic number/length, spine number/density and Sholl-counted dendritic branch points/20 microm) of the basal and apical dendritic systems of Golgi-impregnated CA1 neurons, in the septal and temporal hippocampus of the human and hedgehog tenrec brain. The obtained results indicate that in both hippocampal parts the cellular density of the CA1 pyramidal neurons is lower in human than in tenrec. However, while the human pyramidal cell density is higher in the septal hippocampal part than in the temporal one, in the tenrec the density of these cells is higher in the temporal part. The dendritic tree of the CA1 pyramidal cells, more developed in the septal than in temporal hippocampus in both species studied, is in general more complex in the human hippocampus. The basal and the apical dendritic systems exhibit species related morphometric differences, while dendrites of different orders exhibit differences in their number and length, and in their spine density. Finally, in both species, as well as hippocampal parts and dendritic systems, changes of dendritic morphometric features along ascending dendritic orders fluctuate in a similar way, as do the number of dendritic branch points in relation to the distance from the neuron soma.

Feature-based and statistical methods for analyzing the Deepwater Horizon oil spill with AVIRIS imagery

USGS Publications Warehouse

Rand, R.S.; Clark, R.N.; Livo, K.E.

2011-01-01

The Deepwater Horizon oil spill covered a very large geographical area in the Gulf of Mexico creating potentially serious environmental impacts on both marine life and the coastal shorelines. Knowing the oil's areal extent and thickness as well as denoting different categories of the oil's physical state is important for assessing these impacts. High spectral resolution data in hyperspectral imagery (HSI) sensors such as Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) provide a valuable source of information that can be used for analysis by semi-automatic methods for tracking an oil spill's areal extent, oil thickness, and oil categories. However, the spectral behavior of oil in water is inherently a highly non-linear and variable phenomenon that changes depending on oil thickness and oil/water ratios. For certain oil thicknesses there are well-defined absorption features, whereas for very thin films sometimes there are almost no observable features. Feature-based imaging spectroscopy methods are particularly effective at classifying materials that exhibit specific well-defined spectral absorption features. Statistical methods are effective at classifying materials with spectra that exhibit a considerable amount of variability and that do not necessarily exhibit well-defined spectral absorption features. This study investigates feature-based and statistical methods for analyzing oil spills using hyperspectral imagery. The appropriate use of each approach is investigated and a combined feature-based and statistical method is proposed.

Circulating CD21low B cells in common variable immunodeficiency resemble tissue homing, innate-like B cells

PubMed Central

Rakhmanov, Mirzokhid; Keller, Baerbel; Gutenberger, Sylvia; Foerster, Christian; Hoenig, Manfred; Driessen, Gertjan; van der Burg, Mirjam; van Dongen, Jacques J.; Wiech, Elisabeth; Visentini, Marcella; Quinti, Isabella; Prasse, Antje; Voelxen, Nadine; Salzer, Ulrich; Goldacker, Sigune; Fisch, Paul; Eibel, Hermann; Schwarz, Klaus; Peter, Hans-Hartmut; Warnatz, Klaus

2009-01-01

The homeostasis of circulating B cell subsets in the peripheral blood of healthy adults is well regulated, but in disease it can be severely disturbed. Thus, a subgroup of patients with common variable immunodeficiency (CVID) presents with an extraordinary expansion of an unusual B cell population characterized by the low expression of CD21. CD21low B cells are polyclonal, unmutated IgM+IgD+ B cells but carry a highly distinct gene expression profile which differs from conventional naïve B cells. Interestingly, while clearly not representing a memory population, they do share several features with the recently defined memory-like tissue, Fc receptor-like 4 positive B cell population in the tonsils of healthy donors. CD21low B cells show signs of previous activation and proliferation in vivo, while exhibiting defective calcium signaling and poor proliferation in response to B cell receptor stimulation. CD21low B cells express decreased amounts of homeostatic but increased levels of inflammatory chemokine receptors. This might explain their preferential homing to peripheral tissues like the bronchoalveolar space of CVID or the synovium of rheumatoid arthritis patients. Therefore, as a result of the close resemblance to the gene expression profile, phenotype, function and preferential tissue homing of murine B1 B cells, we suggest that CD21low B cells represent a human innate-like B cell population. PMID:19666505

High-temperature multipass cell for infrared spectroscopy of heated gases and vapors.

PubMed

Bartlome, R; Baer, M; Sigrist, M W

2007-01-01

In absorption spectroscopy, infrared spectra of heated gases or condensed samples in the vapor phase are usually recorded with a single pass heated gas cell. This device exhibits two orders of magnitude lower sensitivity than the high-temperature multipass cell presented in this article. Our device is a novel type of compact long path absorption cell that can withstand aggressive chemicals in addition to temperatures up to 723 K. The construction of the cell and its technical features are described in detail, paying special attention to the mechanisms that compensate for thermal expansion and that allow the user to vary the optical path length under any thermal or vacuum condition. The cell may be used with a laser source or implemented within a Fourier transform infrared spectrometer. Its design is compatible with optical arrangements using astigmatic mirrors or spherical mirrors in a Herriott configuration. Here we implement a homebuilt Herriott-type cell with a total optical path length of up to 35 m. In order to demonstrate the feasibility of the cell, methane and water vapor absorption lines showing dissimilar temperature effects on line intensity were recorded with the help of a mid-infrared laser source tunable between 3 and 4 microm. Emphasis is put on lines that are too weak to be recorded with a single pass cell.

Chromatin position in human HepG2 cells: although being non-random, significantly changed in daughter cells.

PubMed

Cvacková, Zuzana; Masata, Martin; Stanĕk, David; Fidlerová, Helena; Raska, Ivan

2009-02-01

Mammalian chromosomes occupy chromosome territories within nuclear space the positions of which are generally accepted as non-random. However, it is still controversial whether position of chromosome territories/chromatin is maintained in daughter cells. We addressed this issue and investigated maintenance of various chromatin regions of unknown composition as well as nucleolus-associated chromatin, a significant part of which is composed of nucleolus organizer region-bearing chromosomes. The photoconvertible histone H4-Dendra2 was used to label such regions in transfected HepG2 cells, and its position was followed up to next interphase. The distribution of labeled chromatin in daughter cells exhibited a non-random character. However, its distribution in a vast majority of daughter cells extensively differed from the original ones and the labeled nucleolus-associated chromatin differently located into the vicinity of different nucleoli. Therefore, our results were not consistent with a concept of preservation chromatin position. This conclusion was supported by the finding that the numbers of nucleoli significantly differed between the two daughter cells. Our results support a view that while the transfected daughter HepG2 cells maintain some features of the parental cell chromosome organization, there is also a significant stochastic component associated with reassortment of chromosome territories/chromatin that results in their positional rearrangements.

Empirical verification of evolutionary theories of aging.

PubMed

Kyryakov, Pavlo; Gomez-Perez, Alejandra; Glebov, Anastasia; Asbah, Nimara; Bruno, Luigi; Meunier, Carolynne; Iouk, Tatiana; Titorenko, Vladimir I

2016-10-25

We recently selected 3 long-lived mutant strains of Saccharomyces cerevisiae by a lasting exposure to exogenous lithocholic acid. Each mutant strain can maintain the extended chronological lifespan after numerous passages in medium without lithocholic acid. In this study, we used these long-lived yeast mutants for empirical verification of evolutionary theories of aging. We provide evidence that the dominant polygenic trait extending longevity of each of these mutants 1) does not affect such key features of early-life fitness as the exponential growth rate, efficacy of post-exponential growth and fecundity; and 2) enhances such features of early-life fitness as susceptibility to chronic exogenous stresses, and the resistance to apoptotic and liponecrotic forms of programmed cell death. These findings validate evolutionary theories of programmed aging. We also demonstrate that under laboratory conditions that imitate the process of natural selection within an ecosystem, each of these long-lived mutant strains is forced out of the ecosystem by the parental wild-type strain exhibiting shorter lifespan. We therefore concluded that yeast cells have evolved some mechanisms for limiting their lifespan upon reaching a certain chronological age. These mechanisms drive the evolution of yeast longevity towards maintaining a finite yeast chronological lifespan within ecosystems.

Bloom’s Syndrome: Why Not Premature Aging? A comparison of the BLM and WRN helicases

PubMed Central

de Renty, Christelle; Ellis, Nathan A.

2016-01-01

Genomic instability is a hallmark of cancer and aging. Premature aging (progeroid) syndromes are often caused by mutations in genes whose function is to ensure genomic integrity. The RecQ family of DNA helicases is highly conserved and plays crucial roles as genome caretakers. In human, mutations in three RecQ genes — BLM, WRN, and RECQL4 — give rise to Bloom’s syndrome (BS), Werner syndrome (WS), and Rothmund-Thomson’s syndrome (RTS), respectively. WS is a prototypic premature aging disorder; however, the clinical features present in BS and RTS do not indicate accelerated aging. The BLM helicase has pivotal functions at the crossroads of DNA replication, recombination, and repair. BS cells exhibit a characteristic form of genomic instability that includes excessive recombination. The excessive homologous recombination drives the development of the many types of cancers that affect persons in the normal population. Replication delay and slower cell turnover rates have been proposed to explain many features of Bloom’s syndrome, such as short stature. More recently, aberrant transcriptional regulation of growth and survival genes has been proposed as a hypothesis. PMID:27238185

Fabrication of biomimetic resorption lacunae-like structure on titanium surface and its osteoblast responses

NASA Astrophysics Data System (ADS)

Huo, Fangjun; Guo, Weihua; Wu, Hao; Wang, Yueting; He, Gang; Xie, Li; Tian, Weidong

2018-04-01

Biomimetic specific surface structure could improve biological behaviors of specific cells and eventual tissue integration. Featuring titanium surface with structures resembling bone resorption lacunae (RL) can be a promising approach to improve the osteoblast responses and osseointegration of implants. As a most common used dental implant surface, sandblasting and acid etching (SLA) surface has micro-sized structures with dimensions similar to RL, but great differences exist when it comes to shape and contour. In this work, by anodizing titanium substrate in a novel HCOONa/CH3COONa electrolyte, RL-like crater structures were fabricated with highly similar size, shape and contour. Compared with SLA, it was much more similar to RL structure in shape and contour. Furthermore, through subsequent alkali-heat treatment, nano-sized structures that overlaid the whole surface were obtained, which further mimic undercuts features inside the RL. The as-prepared surface was consisted of crystalline titania and exhibited super-hydrophilicity with good stability. In vitro evaluation results showed that the surface could significantly improve adhesion, proliferation and differentiation of MG63 cells in comparison with SLA. This new method may be a promising candidate for biomimetic modification of titanium implant to promote osseointegration.

Hypomorphic PCNA mutation underlies a human DNA repair disorder

PubMed Central

Baple, Emma L.; Chambers, Helen; Cross, Harold E.; Fawcett, Heather; Nakazawa, Yuka; Chioza, Barry A.; Harlalka, Gaurav V.; Mansour, Sahar; Sreekantan-Nair, Ajith; Patton, Michael A.; Muggenthaler, Martina; Rich, Phillip; Wagner, Karin; Coblentz, Roselyn; Stein, Constance K.; Last, James I.; Taylor, A. Malcolm R.; Jackson, Andrew P.; Ogi, Tomoo; Lehmann, Alan R.; Green, Catherine M.; Crosby, Andrew H.

2014-01-01

Numerous human disorders, including Cockayne syndrome, UV-sensitive syndrome, xeroderma pigmentosum, and trichothiodystrophy, result from the mutation of genes encoding molecules important for nucleotide excision repair. Here, we describe a syndrome in which the cardinal clinical features include short stature, hearing loss, premature aging, telangiectasia, neurodegeneration, and photosensitivity, resulting from a homozygous missense (p.Ser228Ile) sequence alteration of the proliferating cell nuclear antigen (PCNA). PCNA is a highly conserved sliding clamp protein essential for DNA replication and repair. Due to this fundamental role, mutations in PCNA that profoundly impair protein function would be incompatible with life. Interestingly, while the p.Ser228Ile alteration appeared to have no effect on protein levels or DNA replication, patient cells exhibited marked abnormalities in response to UV irradiation, displaying substantial reductions in both UV survival and RNA synthesis recovery. The p.Ser228Ile change also profoundly altered PCNA’s interaction with Flap endonuclease 1 and DNA Ligase 1, DNA metabolism enzymes. Together, our findings detail a mutation of PCNA in humans associated with a neurodegenerative phenotype, displaying clinical and molecular features common to other DNA repair disorders, which we showed to be attributable to a hypomorphic amino acid alteration. PMID:24911150

A murine model of autosomal dominant neurohypophyseal diabetes insipidus reveals progressive loss of vasopressin-producing neurons

PubMed Central

Russell, Theron A.; Ito, Masafumi; Ito, Mika; Yu, Richard N.; Martinson, Fred A.; Weiss, Jeffrey; Jameson, J. Larry

2003-01-01

Familial neurohypophyseal diabetes insipidus (FNDI) is an autosomal dominant disorder caused by mutations in the arginine vasopressin (AVP) precursor. The pathogenesis of FNDI is proposed to involve mutant protein–induced loss of AVP-producing neurons. We established murine knock-in models of two different naturally occurring human mutations that cause FNDI. A mutation in the AVP signal sequence [A(–1)T] is associated with a relatively mild phenotype or delayed presentation in humans. This mutation caused no apparent phenotype in mice. In contrast, heterozygous mice expressing a mutation that truncates the AVP precursor (C67X) exhibited polyuria and polydipsia by 2 months of age and these features of DI progressively worsened with age. Studies of the paraventricular and supraoptic nuclei revealed induction of the chaperone protein BiP and progressive loss of AVP-producing neurons relative to oxytocin-producing neurons. In addition, Avp gene products were not detected in the neuronal projections, suggesting retention of WT and mutant AVP precursors within the cell bodies. In summary, this murine model of FNDI recapitulates many features of the human disorder and demonstrates that expression of the mutant AVP precursor leads to progressive neuronal cell loss. PMID:14660745

Cytotoxicity of various types of gold-mesoporous silica nanoparticles in human breast cancer cells

PubMed Central

Liu, Guomu; Li, Qiongshu; Ni, Weihua; Zhang, Nannan; Zheng, Xiao; Wang, Yingshuai; Shao, Dan; Tai, Guixiang

2015-01-01

Recently, gold nanoparticles (AuNPs) have shown promising biological applications due to their unique electronic and optical properties. However, the potential toxicity of AuNPs remains a major hurdle that impedes their use in clinical settings. Mesoporous silica is very suitable for the use as a coating material for AuNPs and might not only reduce the cytotoxicity of cetyltrimethylammonium bromide-coated AuNPs but might also facilitate the loading and delivery of drugs. Herein, three types of rod-like gold-mesoporous silica nanoparticles (termed bare AuNPs, core–shell Au@mSiO2NPs, and Janus Au@mSiO2NPs) were specially designed, and the effects of these AuNPs on cellular uptake, toxic behavior, and mechanism were then systematically studied. Our results indicate that bare AuNPs exerted higher toxicity than the Au@mSiO2NPs and that Janus Au@mSiO2NPs exhibited the lowest toxicity in human breast cancer MCF-7 cells, consistent with the endocytosis capacity of the nanoparticles, which followed the order, bare AuNPs > core–shell Au@mSiO2NPs > Janus Au@mSiO2NPs. More importantly, the AuNPs-induced apoptosis of MCF-7 cells exhibited features that were characteristic of intracellular reactive oxygen species (ROS) generation, activation of c-Jun-N-terminal kinase (JNK) phosphorylation, an enhanced Bax-to-Bcl-2 ratio, and loss of the mitochondrial membrane potential. Simultaneously, cytochrome c was released from mitochondria, and the caspase-3/9 cascade was activated. Moreover, both ROS scavenger (N-acetylcysteine) and JNK inhibitor (SP600125) partly blocked the induction of apoptosis in all AuNPs-treated cells. Taken together, these findings suggest that all AuNPs induce apoptosis through the ROS-/JNK-mediated mitochondrial pathway. Thus, Janus Au@mSiO2NPs exhibit the potential for applications in biomedicine, thus aiding the clinical translation of AuNPs. PMID:26491285

Restoration of Mitochondrial NAD+ Levels Delays Stem Cell Senescence and Facilitates Reprogramming of Aged Somatic Cells.

PubMed

Son, Myung Jin; Kwon, Youjeong; Son, Taekwon; Cho, Yee Sook

2016-12-01

The fundamental tenet that aging is irreversible has been challenged by the development of reprogramming technology that can restore molecular and cellular age by reversing the progression of aging. The use of cells from aged individuals as sources for reprogramming or transplantation creates a major barrier in stem cell therapy with respect to cell quality and quantity. Here, we investigated the molecular features underlying senescence and rejuvenation during aged cell reprogramming and identified novel factors that can overcome age-associated barriers. Enzymes, such as nicotinamide nucleotide transhydrogenase (NNT) and nicotinamide mononucleotide adenylyltransferase 3 (NMNAT3), that control mitochondrial NAD + levels appear to be susceptible to aging. In aged cells, mitochondrial NAD + levels decrease, accompanied by reduced SIRT3 activity; these changes severely impede cell fate transition. However, in cells collected from aged p16 knockout mice, which exhibit delayed cellular senescence, no changes in NNT or NMNAT3 expression were found. Importantly, restoring mitochondrial NAD + levels by overexpressing NNT and NMNAT3 enhanced reprogramming efficiency of aged somatic cells and extended the lifespan of human mesenchymal stem cells by delaying replicative senescence. These results demonstrate that maintenance of mitochondrial NAD + levels is critical for reversing the mechanisms of aging and ensuring that cells collected from aged individuals are of high quality. Stem Cells 2016;34:2840-2851. © 2016 AlphaMed Press.

24(S)-hydroxycholesterol induces neuronal cell death through necroptosis, a form of programmed necrosis.

PubMed

Yamanaka, Kazunori; Saito, Yoshiro; Yamamori, Tohru; Urano, Yasuomi; Noguchi, Noriko

2011-07-15

24(S)-Hydroxycholesterol (24S-OHC) produced by cholesterol 24-hydroxylase expressed mainly in neurons plays an important physiological role in the brain. Conversely, it has been reported that 24S-OHC possesses potent cytotoxicity. The molecular mechanisms of 24S-OHC-induced cell death have not yet been fully elucidated. In this study, using human neuroblastoma SH-SY5Y cells and primary cortical neuronal cells derived from rat embryo, we characterized the form of cell death induced by 24S-OHC. SH-SY5Y cells treated with 24S-OHC exhibited neither fragmentation of the nucleus nor caspase activation, which are the typical characteristics of apoptosis. 24S-OHC-treated cells showed necrosis-like morphological changes but did not induce ATP depletion, one of the features of necrosis. When cells were treated with necrostatin-1, an inhibitor of receptor-interacting serine/threonine kinase 1 (RIPK1) required for necroptosis, 24S-OHC-induced cell death was significantly suppressed. The knockdown of RIPK1 by transfection of small interfering RNA of RIPK1 effectively attenuated 24S-OHC-induced cell death. It was found that neither SH-SY5Y cells nor primary cortical neuronal cells expressed caspase-8, which was regulated for RIPK1-dependent apoptosis. Collectively, these results suggest that 24S-OHC induces neuronal cell death by necroptosis, a form of programmed necrosis.

24(S)-Hydroxycholesterol Induces Neuronal Cell Death through Necroptosis, a Form of Programmed Necrosis*

PubMed Central

Yamanaka, Kazunori; Saito, Yoshiro; Yamamori, Tohru; Urano, Yasuomi; Noguchi, Noriko

2011-01-01

24(S)-Hydroxycholesterol (24S-OHC) produced by cholesterol 24-hydroxylase expressed mainly in neurons plays an important physiological role in the brain. Conversely, it has been reported that 24S-OHC possesses potent cytotoxicity. The molecular mechanisms of 24S-OHC-induced cell death have not yet been fully elucidated. In this study, using human neuroblastoma SH-SY5Y cells and primary cortical neuronal cells derived from rat embryo, we characterized the form of cell death induced by 24S-OHC. SH-SY5Y cells treated with 24S-OHC exhibited neither fragmentation of the nucleus nor caspase activation, which are the typical characteristics of apoptosis. 24S-OHC-treated cells showed necrosis-like morphological changes but did not induce ATP depletion, one of the features of necrosis. When cells were treated with necrostatin-1, an inhibitor of receptor-interacting serine/threonine kinase 1 (RIPK1) required for necroptosis, 24S-OHC-induced cell death was significantly suppressed. The knockdown of RIPK1 by transfection of small interfering RNA of RIPK1 effectively attenuated 24S-OHC-induced cell death. It was found that neither SH-SY5Y cells nor primary cortical neuronal cells expressed caspase-8, which was regulated for RIPK1-dependent apoptosis. Collectively, these results suggest that 24S-OHC induces neuronal cell death by necroptosis, a form of programmed necrosis. PMID:21613228

Phenotypic characterization of aberrant stem and progenitor cell populations in myelodysplastic syndromes.

PubMed

Ostendorf, Benjamin N; Flenner, Eva; Flörcken, Anne; Westermann, Jörg

2018-01-01

Recent reports have revealed myelodysplastic syndromes (MDS) to arise from cancer stem cells phenotypically similar to physiological hematopoietic stem cells. Myelodysplastic hematopoiesis maintains a hierarchical organization, but the proportion of several hematopoietic compartments is skewed and multiple surface markers are aberrantly expressed. These aberrant antigen expression patterns hold diagnostic and therapeutic promise. However, eradication of MDS requires targeting of early myelodysplasia propagating stem cells. This warrants an exact assessment of the differentiation stage at which aberrant expression occurs in transformed hematopoiesis. Here, we report results on the prospective and extensive dissection of the hematopoietic hierarchy in 20 patients with either low-risk MDS or MDS with excess blasts and compare it to hematopoiesis in patients with non-malignancy-associated cytopenia or B cell lymphoma without bone marrow infiltration. We found patients with MDS with excess blasts to exhibit characteristic expansions of specific immature progenitor compartments. We also identified the aberrant expression of several markers including ALDH, CLL-1, CD44, and CD47 to be specific features of hematopoiesis in MDS with excess blasts. We show that amongst these, aberrant CLL-1 expression manifested at the early uncommitted hematopoietic stem cell level, suggesting a potential role as a therapeutic target.

Cyanidin-3-glucoside isolated from mulberry fruits protects pancreatic β-cells against glucotoxicity-induced apoptosis.

PubMed

Lee, Jong Seok; Kim, Young Rae; Park, Jun Myoung; Kim, Young Eon; Baek, Nam In; Hong, Eock Kee

2015-04-01

The present study investigated the cytoprotective effects of cyanidin‑3‑glucoside (C3G), isolated from mulberry fruits, on the glucotoxicity‑induced apoptosis of pancreatic β‑cells to evaluate the antidiabetic effects of this compound. MIN6N pancreatic β‑cells were used to investigate the cytoprotective effects of C3G. In addition, the effects of C3G on the glucotoxicity‑induced apoptosis of pancreatic β‑cells was evaluated using MTT assay, immunofluorescent staining, flow cytometric and western blot analyses. The pancreatic β‑cells cultured under high glucose conditions exhibited distinct apoptotic features. C3G decreased the generation of intracellular reactive oxygen species, DNA fragmentation and the rate of apoptosis. C3G also prevented pancreatic β‑cell apoptosis induced by high glucose conditions by interfering with the intrinsic apoptotic pathways. In addition, C3G treatment resulted in increased insulin secretion compared with treatment with high glucose only. In conclusion, the results of the present study suggested that C3G obtained from mulberry fruits may be a potential phytotherapeutic agent for the prevention of diabetes.

Place Cell Networks in Pre-weanling Rats Show Associative Memory Properties from the Onset of Exploratory Behavior.

PubMed

Muessig, L; Hauser, J; Wills, T J; Cacucci, F

2016-08-01

Place cells are hippocampal pyramidal cells that are active when an animal visits a restricted area of the environment, and collectively their activity constitutes a neural representation of space. Place cell populations in the adult rat hippocampus display fundamental properties consistent with an associative memory network: the ability to 1) generate new and distinct spatial firing patterns when encountering novel spatial contexts or changes in sensory input ("remapping") and 2) reinstate previously stored firing patterns when encountering a familiar context, including on the basis of an incomplete/degraded set of sensory cues ("pattern completion"). To date, it is unknown when these spatial memory responses emerge during brain development. Here, we show that, from the age of first exploration (postnatal day 16) onwards, place cell populations already exhibit these key features: they generate new representations upon exposure to a novel context and can reactivate familiar representations on the basis of an incomplete set of sensory cues. These results demonstrate that, as early as exploratory behaviors emerge, and despite the absence of an adult-like grid cell network, the developing hippocampus processes incoming sensory information as an associative memory network. © The Author 2016. Published by Oxford University Press.

The Interaction Between IGF-1, Atherosclerosis and Vascular Aging

PubMed Central

Higashi, Yusuke; Quevedo, Henry C.; Tiwari, Summit; Sukhanov, Sergiy; Shai, Shaw-Yung; Anwar, Asif; Delafontaine, Patrice

2014-01-01

The process of vascular aging encompasses alterations in the function of endothelial (EC) and vascular smooth muscle cells (VSMCs) via oxidation, inflammation, cell senescence and epigenetic modifications, increasing the probability of atherosclerosis. Aged vessels exhibit decreased endothelial antithrombogenic properties, increased reactive oxygen species (ROS) generation and inflammatory signaling, increased migration of VSMCs to the subintimal space, impaired angiogenesis and increased elastin degradation. The key initiating step in atherogenesis is subendothelial accumulation of apolipoprotein-B containing low density lipoproteins resulting in activation of endothelial cells and recruitment of monocytes. Activated endothelial cells secrete “chemokines” that interact with cognate chemokine receptors on monocytes and promote directional migration. Recruitment of immune cells establishes a pro-inflammatory status, further causing elevated oxidative stress, which in turn triggers a series of events including apoptotic or necrotic death of vascular and non-vascular cells. Increased oxidative stress is also considered to be a key factor in mechanisms of aging-associated changes in tissue integrity and function. Experimental evidence indicates that insulin-like growth factor-1 (IGF-1) exerts anti-oxidant, anti-inflammatory and pro-survival effects on the vasculature, reducing atherosclerotic plaque burden and promoting features of atherosclerotic plaque stability. PMID:24943302

[Morphological characteristic of Langerhans cells from the human epidermis in case of general hypothermia].

PubMed

Stefanenko, E V; Miadelets, O D; Kukhnovets, O A; Miadelets, V O

2009-01-01

The objective of this work was to study morphological changes in the Langerhans cells of epidermis and epithelium of hair follicles from subjects who died as a result of general hypothermia. A total of 105 cadaveric skin samples from subjects of either gender aged from 19 to 83 years were available for analysis. Postmortem examination 1-2 days after death was performed at the Department of Forensic Medical Examination for the Vitebsk region. Skin samples were frozen in liquid nitrogen and studied as cryostat sections. Langerhans cells were detected using the ATPase assay as described by Wachstein and Meisel and modified by Robins and Brendon. The Langerhans cells of subjects who died from general hypothermia were shown to undergo marked morphological changes. Moreover, their number significantly decreased as a result of disintegration and transformation into fine-grain material. Surviving cells lost many of their outgrowths and exhibited enhanced ATPase activity in pericarion. The Langerhans cells from dorsal and ventral skin as well as from interfollicular epidermis and the outer sheath of hair follicles underwent virtually identical changes. A unique morphological feature of the skin in those who died from general hypothermia was formation of intraepidermal, subepidermal, and dermal blisters.

Initial contact guidance during cell spreading is contractility-independent.

PubMed

Sales, Adrià; Holle, Andrew W; Kemkemer, Ralf

2017-08-02

A wide variety of cell types exhibit substrate topography-based behavior, also known as contact guidance. However, the precise cellular mechanisms underlying this process are still unknown. In this study, we investigated contact guidance by studying the reaction of human endothelial cells (ECs) to well-defined microgroove topographies, both during and after initial cell spreading. As the cytoskeleton plays a major role in cellular adaptation to topographical features, two methods were used to perturb cytoskeletal structures. Inhibition of actomyosin contractility with the chemical inhibitor blebbistatatin demonstrated that initial contact guidance events are independent of traction force generation. However, cell alignment to the grooved substrate was altered at later time points, suggesting an initial 'passive' phase of contact guidance, followed by a contractility-dependent 'active' phase that relies on mechanosensitive feedback. The actin cytoskeleton was also perturbed in an indirect manner by culturing cells upside down, resulting in decreased levels of contact guidance and suggesting that a possible loss of contact between the actin cytoskeleton and the substrate could lead to cytoskeleton impairment. The process of contact guidance at the microscale was found to be primarily lamellipodia driven, as no bias in filopodia extension was observed on micron-scale grooves.

Simple mechanisms of early life - simulation model on the origin of semi-cells.

PubMed

Klein, Adrian; Bock, Martin; Alt, Wolfgang

2017-01-01

The development of first cellular structures played an important role in the early evolution of life. Early evolution of life probably took place on a molecular level in a reactive environment. The iron-sulfur theory postulates the formation of cell-like structures on catalytic surfaces. Experiments show that H 2 S together with FeS and other metallic centers drive auto-catalytic surface reactions, in which organic molecules such as pyruvic and amino acids occur. It is questionable which mechanisms are needed to form cell-like structures under these conditions. To address this question, we implemented a model system featuring the fundamentals of molecular dynamics: heat, attraction, repulsion and formation of covalent bonds. Our basic model exhibits a series of essential processes: self-organization of lipid micelles and bilayers, formation of fluid filled cavities, flux of molecules along membranes, transport of energized groups towards sinks and whole colonies of cell-like structures on a larger scale. The results demonstrate that only a few features are sufficient for discovering hitherto non described phenomena of self-assembly and dynamics of cell-like structures as candidates for early evolving proto-cells. Significance statement The quest for a possible origin of life continues to be one of the most fascinating problems in biology. In one theoretical scenario, early life originated from a solution of reactive chemicals in the ancient deep sea, similar to conditions as to be found in thermal vents. Experiments have shown that a variety of organic molecules, the building blocks of life, form under these conditions. Based on such experiments, the iron-sulfur theory postulates the growth of cell-like structures at certain catalytic surfaces. For an explanation and proof of such a process we have developed a computer model simulating molecular assembly of lipid bilayers and formation of semi-cell cavities. The results demonstrate the possibility of cell-like self-organization under appropriate physico-chemical conditions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Ependyma of the central canal of the rat spinal cord: a light and transmission electron microscopic study.

PubMed Central

Bruni, J E; Reddy, K

1987-01-01

Ependymal cells of the rat central canal were examined with a view to identifying features that distinguish them regionally and from their counterparts elsewhere in the ventricular system. The results revealed that the lining consisted for the most part of a pseudostratified layer of uniformly organised cuboidal to columnar ependymal cells present in largest numbers in lumbar and sacral segments and in the conus. Two cell variants were identified on the basis of the presence or absence of a radially directed cytoplasmic process originating from the base of the cell. The tanycytic form of ependymal cell was encountered along the entire length of the central canal but with increased frequency in caudalmost segments. Ependymal cells were largely similar in ultrastructural appearance along the length of the cord. Although they were also similar in appearance and orientation to their counterparts in the ventricles they did exhibit some unique features. The most notable were the prominent junctional complexes and associated filaments present along the lateral border of the cells near their apex and the abundance of intermediate filaments in tanycytes. The central canal of the filum differed most markedly from other segments of the cord and resembled in structure the primitive ependymal tube of the caudal cord in lower vertebrates. Ependymal cells of the cord were not sufficiently dissimilar morphologically from their counterparts in the ventricles to account for differences in proliferative capacity in response to localised injury. A factor that merits further study is the difference in numbers of tanycyte ependymal cells in the two locations for they may be the reactive elements that proliferate in response to injury. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 PMID:3654376

An azodye-rhodamine-based fluorescent and colorimetric probe specific for the detection of Pd(2+) in aqueous ethanolic solution: synthesis, XRD characterization, computational studies and imaging in live cells.

PubMed

Mahapatra, Ajit Kumar; Manna, Saikat Kumar; Maiti, Kalipada; Mondal, Sanchita; Maji, Rajkishor; Mandal, Debasish; Mandal, Sukhendu; Uddin, Md Raihan; Goswami, Shyamaprosad; Quah, Ching Kheng; Fun, Hoong-Kun

2015-02-21

Azodye-rhodamine hybrid colorimetric fluorescent probe (L) has been designed and synthesized. The structure of L has been established based on single crystal XRD. It has been shown to act as a selective turn-on fluorescent chemosensor for Pd(2+) with >40 fold enhancement by exhibiting red emission among the other 27 cations studied in aqueous ethanol. The coordination features of the species of recognition have been computationally evaluated by DFT methods and found to have a distorted tetrahedral Pd(2+) center in the binding core. The probe (L) has been shown to detect Pd up to 0.45 μM at pH 7.4. Furthermore, the probe can be used to image Pd(2+) in living cells.

Ulnar nerve sonography in leprosy neuropathy.

PubMed

Wang, Zhu; Liu, Da-Yue; Lei, Yang-Yang; Yang, Zheng; Wang, Wei

2016-01-01

A 23-year-old woman presented with a half-year history of right forearm sensory and motor dysfunction. Ultrasound imaging revealed definite thickening of the right ulnar nerve trunk and inner epineurium, along with heterogeneous hypoechogenicity and unclear nerve fiber bundle. Color Doppler exhibited a rich blood supply, which was clearly different from the normal ulnar nerve presentation with a scarce blood supply. The patient subsequently underwent needle aspiration of the right ulnar nerve, and histopathological examination confirmed that granulomatous nodules had formed with a large number of infiltrating lymphocytes and a plurality of epithelioid cells in the fibrous connective tissues, with visible atypical foam cells and proliferous vascularization, consistent with leprosy. Our report will familiarize readers with the characteristic sonographic features of the ulnar nerve in leprosy, particularly because of the decreasing incidence of leprosy in recent years.

IRF-4 and c-Rel expression in antiviral-resistant adult T-cell leukemia/lymphoma

PubMed Central

Ramos, Juan Carlos; Ruiz, Phillip; Ratner, Lee; Reis, Isildinha M.; Brites, Carlos; Pedroso, Celia; Byrne, Gerald E.; Toomey, Ngoc L.; Andela, Valentine; Harhaj, Edward W.; Lossos, Izidore S.

2007-01-01

Adult T-cell leukemia/lymphoma (ATLL) is a generally fatal malignancy. Most ATLL patients fare poorly with conventional chemotherapy; however, antiviral therapy with zidovudine (AZT) and interferon alpha (IFN-α) has produced long-term clinical remissions. We studied primary ATLL tumors and identified molecular features linked to sensitivity and resistance to antiviral therapy. Enhanced expression of the proto-oncogene c-Rel was noted in 9 of 27 tumors. Resistant tumors exhibited c-Rel (6 of 10; 60%) more often than did sensitive variants (1 of 9; 11%). This finding was independent of the disease form. Elevated expression of the putative c-Rel target, interferon regulatory factor-4 (IRF-4), was observed in 10 (91%) of 11 nonresponders and in all tested patients with c-Rel+ tumors and occurred in the absence of the HTLV-1 oncoprotein Tax. In contrast, tumors in complete responders did not express c-Rel or IRF-4. Gene rearrangement studies demonstrated the persistence of circulating T-cell clones in long-term survivors maintained on antiviral therapy. The expression of nuclear c-Rel and IRF-4 occurs in the absence of Tax in primary ATLL and is associated with antiviral resistance. These molecular features may help guide treatment. AZT and IFN-α is a suppressive rather than a curative regimen, and patients in clinical remission should remain on maintenance therapy indefinitely. PMID:17138822

Loss of the Na+/H+ exchanger NHE8 causes male infertility in mice by disrupting acrosome formation.

PubMed

Oberheide, Karina; Puchkov, Dmytro; Jentsch, Thomas J

2017-06-30

Mammalian sperm feature a specialized secretory organelle on the anterior part of the sperm nucleus, the acrosome, which is essential for male fertility. It is formed by a fusion of Golgi-derived vesicles. We show here that the predominantly Golgi-resident Na + /H + exchanger NHE8 localizes to the developing acrosome of spermatids. Similar to wild-type mice, Nhe8 -/- mice generated Golgi-derived vesicles positive for acrosomal markers and attached to nuclei, but these vesicles failed to form large acrosomal granules and the acrosomal cap. Spermatozoa from Nhe8 -/- mice completely lacked acrosomes, were round-headed, exhibited abnormal mitochondrial distribution, and displayed decreased motility, resulting in selective male infertility. Of note, similar features are also found in globozoospermia, one of the causes of male infertility in humans. Germ cell-specific, but not Sertoli cell-specific Nhe8 disruption recapitulated the globozoospermia phenotype, demonstrating that NHE8's role in spermiogenesis is germ cell-intrinsic. Our work has uncovered a crucial role of NHE8 in acrosome biogenesis and suggests that some forms of human globozoospermia might be caused by a loss of function of this Na + /H + exchanger. It points to NHE8 as a candidate gene for human globozoospermia and a possible drug target for male contraception. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Ineffectiveness of the presence of H-ras/p53 combination of mutations in squamous cell carcinoma cells to induce a conversion of a nontumorigenic to a tumorigenic phenotype.

PubMed

Lee, H; Li, D; Prior, T; Casto, B C; Weghorst, C M; Shuler, C F; Milo, G E

1997-10-01

Human tumor cells have properties in vitro or in surrogate hosts that are distinct from those of normal cells, such as immortality, anchorage independence, and tumor formation in nude mice. However, different cells from individual tumors may exhibit some, but not all of these features. In previous years, human tumor cell lines derived from different tumor and tissue types have been studied to determine those molecular changes that are associated with the in vitro properties listed above and with tumorigenicity in nude mice. In the present study, seven cell lines derived from human tumors were characterized for p53 and ras mutations that may occur in SCC tumor phenotypes and for tumor formation in nude mice. This investigation was designed to examine whether co-occurrence of mutated ras and p53 lead to a malignant stage in the progression process. None of the seven cell lines contained mutations in the recognized "hot spots" of the p53 tumor suppressor gene, but four had a nonsense/splice mutation in codon 126 and a mutation in codon 12 of the H-ras gene. The remaining three cell lines had p53 mutations in intron 5, in codon 193, and a missense mutation in codon 126, respectively. Four of seven cell lines were nontumorigenic; two of these cell lines contained a nonsense p53-126 mutation and mutated ras; one had a missense mutation at codon 126 but no mutated ras; the the fourth had only a p53 mutation at codon 193. Two of the nontumorigenic cell lines were converted to tumorigenicity after treatment with methyl methanesulfonate or N-methyl-N'-nitro-N-nitrosoguanidine with no apparent additional mutations in either gene. Our analysis revealed that there was a high frequency of genetic diversity and mutations in both p53 and H-ras. There was also a lack of a causal relationship in the presence of mutations in p53 and the cells' ability to exhibit a malignant potential in nude mice.

Discovering monotonic stemness marker genes from time-series stem cell microarray data.

PubMed

Wang, Hsei-Wei; Sun, Hsing-Jen; Chang, Ting-Yu; Lo, Hung-Hao; Cheng, Wei-Chung; Tseng, George C; Lin, Chin-Teng; Chang, Shing-Jyh; Pal, Nikhil; Chung, I-Fang

2015-01-01

Identification of genes with ascending or descending monotonic expression patterns over time or stages of stem cells is an important issue in time-series microarray data analysis. We propose a method named Monotonic Feature Selector (MFSelector) based on a concept of total discriminating error (DEtotal) to identify monotonic genes. MFSelector considers various time stages in stage order (i.e., Stage One vs. other stages, Stages One and Two vs. remaining stages and so on) and computes DEtotal of each gene. MFSelector can successfully identify genes with monotonic characteristics. We have demonstrated the effectiveness of MFSelector on two synthetic data sets and two stem cell differentiation data sets: embryonic stem cell neurogenesis (ESCN) and embryonic stem cell vasculogenesis (ESCV) data sets. We have also performed extensive quantitative comparisons of the three monotonic gene selection approaches. Some of the monotonic marker genes such as OCT4, NANOG, BLBP, discovered from the ESCN dataset exhibit consistent behavior with that reported in other studies. The role of monotonic genes found by MFSelector in either stemness or differentiation is validated using information obtained from Gene Ontology analysis and other literature. We justify and demonstrate that descending genes are involved in the proliferation or self-renewal activity of stem cells, while ascending genes are involved in differentiation of stem cells into variant cell lineages. We have developed a novel system, easy to use even with no pre-existing knowledge, to identify gene sets with monotonic expression patterns in multi-stage as well as in time-series genomics matrices. The case studies on ESCN and ESCV have helped to get a better understanding of stemness and differentiation. The novel monotonic marker genes discovered from a data set are found to exhibit consistent behavior in another independent data set, demonstrating the utility of the proposed method. The MFSelector R function and data sets can be downloaded from: http://microarray.ym.edu.tw/tools/MFSelector/.

Cutaneous lymphomatoid granulomatosis: correlation of clinical and biologic features.

PubMed

Beaty, M W; Toro, J; Sorbara, L; Stern, J B; Pittaluga, S; Raffeld, M; Wilson, W H; Jaffe, E S

2001-09-01

Lymphomatoid granulomatosis (LYG) is a rare angiocentric and angiodestructive Epstein-Barr virus-associated B-cell lymphoproliferative disorder (EBV-BLPD), varying widely from an indolent process to an aggressive large cell lymphoma. The skin is the extrapulmonary organ most commonly involved in LYG. We studied 32 skin lesions from 20 patients with known pulmonary LYG, using immunohistochemistry, in situ hybridization for EBV, and polymerase chain reaction for the presence of antigen receptor gene rearrangements (IgH and TCR) to better define both the clinicopathologic spectrum and pathogenesis of the cutaneous lesions. We describe two distinct patterns of cutaneous involvement. Multiple erythematous dermal papules and/or subcutaneous nodules, with or without ulceration, were present in 17 patients (85%). These lesions demonstrate a marked angiocentric lymphohistiocytic infiltrate, composed predominantly of CD4-positive T-cells, with a high propensity for involving the subcutaneous tissues, and exhibiting angiodestruction, necrosis, and cytologic atypia. EBV-positive B-cells were detected in the nodules from five patients; clonal immunoglobulin heavy chain gene (IgH) rearrangements were detected by polymerase chain reaction in two patients. Multiple indurated, erythematous to white plaques were present in three patients (15%). The plaque lesions were negative for EBV and clonal IgH gene rearrangements in all cases studied. The clinical course of overall disease was variable, ranging from spontaneous regression without treatment (1 of 13; 7%), resolution with chemo/immunomodulatory therapy (8 of 13; 62%), and progression (4 of 13; 31%). The clinical and histopathologic features of cutaneous LYG are extremely diverse. However, the majority (85%) of the cutaneous lesions mirrors to some extent LYG in the lung, although EBV+ cells are less frequently identified. This subset of cases shows the histopathologic triad of angiodestruction with associated necrosis, panniculitis, and in some cases atypical lymphoid cells. The commonality of the histologic features in this group suggests a common pathophysiologic basis, possibly mediated by cytokines and chemokines induced by EBV. A small percentage of the lesions (15%) presented as indurated and atrophic plaques, and EBV was not identified in the small number of cases studied. The relationship of the plaque-like lesions to LYG remains uncertain. Whereas some cases of LYG regress spontaneously, most require therapy.

Functional characterization of T cells in abdominal aortic aneurysms.

PubMed

Forester, Nerys D; Cruickshank, Sheena M; Scott, D Julian A; Carding, Simon R

2005-06-01

Abdominal aortic aneurysms (AAA) exhibit features of a chronic inflammatory disorder. The functional attributes of the T cells in AAA tissue are unclear, with little quantitative or functional data. Using a novel, non-enzymatic method to isolate viable cells from AAA tissue, functional properties of AAA T cells were investigated for the first time. Composition and phenotype of AAA T cells was determined by flow cytometry and verified by immunohistochemistry. Tissue mononuclear cells (MNCs) were cultured in the presence of T-cell mitogens, and cell cycle analysis and cytokine production assessed. Typical cell yield was 4.5 x 10(6) cells per gram of AAA tissue. The majority (58.1+/-5.3%) of haematopoietic (CD45+) cells recovered were CD3+ T cells, B cells comprised 41.1+/-5.7%, natural killer cells 7.3+/-2.5%, and macrophages 2%. Freshly isolated T cells were in resting (G1) state, with 25% expressing the activation-associated cell surface antigens major histocompatibility complex II and CD25. When stimulated in vitro, a significant proportion entered S and G2 phase of the cell cycle, up-regulated CD25, and secreted tumour necrosis factor-alpha, interferon-gamma, interleukin (IL)-5 and IL-6. Despite patient differences, the composition of the AAA inflammatory infiltrate was remarkably consistent, and when re-stimulated ex-vivo T cells produced a stereotypical cytokine response, consistent with the hypothesis that AAA T cells can promote tissue inflammation by secretion of proinflammatory cytokines, and in addition provide signals for B-cell help.

Changes in fine structure of pericytes and novel desmin-immunopositive perivascular cells during postnatal development in rat anterior pituitary gland.

PubMed

Jindatip, Depicha; Fujiwara, Ken; Horiguchi, Kotaro; Tsukada, Takehiro; Kouki, Tom; Yashiro, Takashi

2013-09-01

Pericytes are perivascular cells associated with capillaries. We previously demonstrated that pericytes, identified by desmin immunohistochemistry, produce type I and III collagens in the anterior pituitary gland of adult rats. In addition, we recently used desmin immunoelectron microscopy to characterize a novel type of perivascular cell, dubbed a desmin-immunopositive perivascular cell, in the anterior pituitary. These two types of perivascular cells differ in fine structure. The present study attempted to characterize the morphological features of pituitary pericytes and novel desmin-immunopositive perivascular cells during postnatal development, in particular their role in collagen synthesis. Desmin immunostaining revealed numerous perivascular cells at postnatal day 5 (P5) and P10. Transmission electron microscopy showed differences in the fine structure of the two cell types, starting at P5. Pericytes had well-developed rough endoplasmic reticulum and Golgi apparatus at P5 and P10. The novel desmin-immunopositive perivascular cells exhibited dilated cisternae of rough endoplasmic reticulum at P5-P30. In addition, during early postnatal development in the gland, a number of type I and III collagen-expressing cells were observed, as were high expression levels of these collagen mRNAs. We conclude that pituitary pericytes and novel desmin-immunopositive perivascular cells contain well-developed cell organelles and that they actively synthesize collagens during the early postnatal period.

VA-086 methacrylate gelatine photopolymerizable hydrogels: A parametric study for highly biocompatible 3D cell embedding.

PubMed

Occhetta, Paola; Visone, Roberta; Russo, Laura; Cipolla, Laura; Moretti, Matteo; Rasponi, Marco

2015-06-01

The ability to replicate in vitro the native extracellular matrix (ECM) features and to control the three-dimensional (3D) cell organization plays a fundamental role in obtaining functional engineered bioconstructs. In tissue engineering (TE) applications, hydrogels have been successfully implied as biomatrices for 3D cell embedding, exhibiting high similarities to the natural ECM and holding easily tunable mechanical properties. In the present study, we characterized a promising photocrosslinking process to generate cell-laden methacrylate gelatin (GelMA) hydrogels in the presence of VA-086 photoinitiator using a ultraviolet LED source. We investigated the influence of prepolymer concentration and light irradiance on mechanical and biomimetic properties of resulting hydrogels. In details, the increasing of gelatin concentration resulted in enhanced rheological properties and shorter polymerization time. We then defined and validated a reliable photopolymerization protocol for cell embedding (1.5% VA-086, LED 2 mW/cm2) within GelMA hydrogels, which demonstrated to support bone marrow stromal cells viability when cultured up to 7 days. Moreover, we showed how different mechanical properties, derived from different crosslinking parameters, strongly influence cell behavior. In conclusion, this protocol can be considered a versatile tool to obtain biocompatible cell-laden hydrogels with properties easily adaptable for different TE applications. © 2014 Wiley Periodicals, Inc.

Inferences of drug responses in cancer cells from cancer genomic features and compound chemical and therapeutic properties

PubMed Central

Wang, Yongcui; Fang, Jianwen; Chen, Shilong

2016-01-01

Accurately predicting the response of a cancer patient to a therapeutic agent is a core goal of precision medicine. Existing approaches were mainly relied primarily on genomic alterations in cancer cells that have been treated with different drugs. Here we focus on predicting drug response based on integration of the heterogeneously pharmacogenomics data from both cell and drug sides. Through a systematical approach, named as PDRCC (Predict Drug Response in Cancer Cells), the cancer genomic alterations and compound chemical and therapeutic properties were incorporated to determine the chemotherapeutic response in cancer patients. Using the Cancer Cell Line Encyclopedia (CCLE) study as the benchmark dataset, all pharmacogenomics data exhibited their roles in inferring the relationships between cancer cells and drugs. When integrating both genomic resources and compound information, the prediction coverage was significantly increased. The validity of PDRCC was also supported by its effective in uncovering the unknown cell-drug associations with database and literature evidences. It set the stage for clinical testing of novel therapeutic strategies, such as the sensitive association between cancer cell ‘A549_LUNG’ and compound ‘Topotecan’. In conclusion, PDRCC offers the possibility for faster, safer, and cheaper the development of novel anti-cancer therapeutics in the early-stage clinical trails. PMID:27645580

Inferences of drug responses in cancer cells from cancer genomic features and compound chemical and therapeutic properties

NASA Astrophysics Data System (ADS)

Wang, Yongcui; Fang, Jianwen; Chen, Shilong

2016-09-01

Accurately predicting the response of a cancer patient to a therapeutic agent is a core goal of precision medicine. Existing approaches were mainly relied primarily on genomic alterations in cancer cells that have been treated with different drugs. Here we focus on predicting drug response based on integration of the heterogeneously pharmacogenomics data from both cell and drug sides. Through a systematical approach, named as PDRCC (Predict Drug Response in Cancer Cells), the cancer genomic alterations and compound chemical and therapeutic properties were incorporated to determine the chemotherapeutic response in cancer patients. Using the Cancer Cell Line Encyclopedia (CCLE) study as the benchmark dataset, all pharmacogenomics data exhibited their roles in inferring the relationships between cancer cells and drugs. When integrating both genomic resources and compound information, the prediction coverage was significantly increased. The validity of PDRCC was also supported by its effective in uncovering the unknown cell-drug associations with database and literature evidences. It set the stage for clinical testing of novel therapeutic strategies, such as the sensitive association between cancer cell ‘A549_LUNG’ and compound ‘Topotecan’. In conclusion, PDRCC offers the possibility for faster, safer, and cheaper the development of novel anti-cancer therapeutics in the early-stage clinical trails.

NOTCH2 signaling confers immature morphology and aggressiveness in human hepatocellular carcinoma cells

PubMed Central

HAYASHI, YOSHIHIRO; OSANAI, MAKOTO; LEE, GANG-HONG

2015-01-01

The NOTCH family of membranous receptors plays key roles during development and carcinogenesis. Since NOTCH2, yet not NOTCH1 has been shown essential for murine hepatogenesis, NOTCH2 rather than NOTCH1 may be more relevant to human hepatocarcinogenesis; however, no previous studies have supported this hypothesis. We therefore assessed the role of NOTCH2 in human hepatocellular carcinoma (HCC) by immunohistochemistry and cell culture. Immunohistochemically, 19% of primary HCCs showed nuclear staining for NOTCH2, indicating activated NOTCH2 signaling. NOTCH2-positive HCCs were on average in more advanced clinical stages, and exhibited more immature cellular morphology, i.e. higher nuclear-cytoplasmic ratios and nuclear densities. Such features were not evident in NOTCH1-positive HCCs. In human HCC cell lines, abundant NOTCH2 expression was associated with anaplasia, represented by loss of E-cadherin. When NOTCH2 signaling was stably downregulated in HLF cells, an anaplastic HCC cell line, the cells were attenuated in potential for in vitro invasiveness and migration, as well as in vivo tumorigenicity accompanied by histological maturation. Generally, inverse results were obtained for a differentiated HCC cell line, Huh7, manipulated to overexpress activated NOTCH2. These findings suggested that the NOTCH2 signaling may confer aggressive behavior and immature morphology in human HCC cells. PMID:26252838

NOTCH2 signaling confers immature morphology and aggressiveness in human hepatocellular carcinoma cells.

PubMed

Hayashi, Yoshihiro; Osanai, Makoto; Lee, Gang-Hong

2015-10-01

The NOTCH family of membranous receptors plays key roles during development and carcinogenesis. Since NOTCH2, yet not NOTCH1 has been shown essential for murine hepatogenesis, NOTCH2 rather than NOTCH1 may be more relevant to human hepatocarcinogenesis; however, no previous studies have supported this hypothesis. We therefore assessed the role of NOTCH2 in human hepatocellular carcinoma (HCC) by immunohistochemistry and cell culture. Immunohistochemically, 19% of primary HCCs showed nuclear staining for NOTCH2, indicating activated NOTCH2 signaling. NOTCH2-positive HCCs were on average in more advanced clinical stages, and exhibited more immature cellular morphology, i.e. higher nuclear-cytoplasmic ratios and nuclear densities. Such features were not evident in NOTCH1‑positive HCCs. In human HCC cell lines, abundant NOTCH2 expression was associated with anaplasia, represented by loss of E-cadherin. When NOTCH2 signaling was stably downregulated in HLF cells, an anaplastic HCC cell line, the cells were attenuated in potential for in vitro invasiveness and migration, as well as in vivo tumorigenicity accompanied by histological maturation. Generally, inverse results were obtained for a differentiated HCC cell line, Huh7, manipulated to overexpress activated NOTCH2. These findings suggested that the NOTCH2 signaling may confer aggressive behavior and immature morphology in human HCC cells.

‘Hints' in the killer protein gasdermin D: unveiling the secrets of gasdermins driving cell death

PubMed Central

Qiu, Shiqiao; Liu, Jing; Xing, Feiyue

2017-01-01

Pyroptosis is a lytic form of cell death distinguished from apoptosis, ferroptosis, necrosis, necroptosis, NETosis, oncosis, pyronecrosis and autophagy. Proinflammatory caspases cleave a gasdermin D (GSDMD) protein to generate a 31 kDa N-terminal domain. The cleavage relieves the intramolecular inhibition on the gasdermin-N domain, which then moves to the plasma membrane to exhibit pore-forming activity. Thus, GSDMD acts as the final and direct executor of pyroptotic cell death. Owing to the selective targeting of the inner leaflet of the plasma membrane with the pore-forming that determines pyroptotic cell death, GSDMD could be a potential target to control cell death or extracellular bacterial infections. Intriguingly, other gasdermin family members also share similar N-terminal domains, but they present different cell death programs. Herein, we summarize features and functions of the novel player proteins in cell death, including GSDMD triggering pyroptosis, Gsdma3/GSDMA initiating autophagy/apoptosis and DFNA5 inducing apoptosis/secondary necrosis. The gasdermin N terminus appears to be a novel pore-forming protein. This provides novel insight into the underlying roles and mechanisms of lytic or nonlytic forms of programmed cell death, as well as their potential applications in inflammation-associated diseases. PMID:28362726

Changes in global gene expression during in vitro decidualization of rat endometrial stromal cells

PubMed Central

Vallejo, Griselda; Maschi, Darío; Citrinovitz, Ana Cecilia Mestre; Aiba, Kazuhiro; Maronna, Ricardo; Yohai, Victor; Ko, Minoru S. H.; Beato, Miguel; Saragüeta, Patricia

2009-01-01

During the preimplantation phase of pregnancy the endometrial stroma differentiates into decidua, a process that implies numerous morphological changes and is an example of physiological transdifferentiation. Here we show that UIII rat endometrial stromal cells cultured in the presence of calf serum acquired morphological features of decidual cells and expressed decidual markers. To identify genes involved in decidualization we compared gene expression patterns of control and decidualized UIII cells using cDNA microarray. We found 322 annotated genes exhibiting significant differences in expression (>3 fold, FDR > 0.005), of which 312 have not been previously related to decidualization. Analysis of overrepresented functions revealed that protein synthesis, gene expression and chromatin architecture and remodeling are the most relevant modified functions during decidualization. Relevant genes are also found in the functional terms differentiation, cell proliferation, signal transduction, and matrix/structural proteins. Several of these new genes involved in decidualization (Csdc2, Trim27, Eef1a1, Bmp1, Wt1, Aes, Gna12, and Men1) are shown to be also regulated in uterine decidua during normal pregnancy. Thus, the UIII cell culture model will allow future mechanistic studies to define the transcriptional network regulating reprogramming of stromal cells into decidual cells. PMID:19780023

Inferences of drug responses in cancer cells from cancer genomic features and compound chemical and therapeutic properties.

PubMed

Wang, Yongcui; Fang, Jianwen; Chen, Shilong

2016-09-20

Accurately predicting the response of a cancer patient to a therapeutic agent is a core goal of precision medicine. Existing approaches were mainly relied primarily on genomic alterations in cancer cells that have been treated with different drugs. Here we focus on predicting drug response based on integration of the heterogeneously pharmacogenomics data from both cell and drug sides. Through a systematical approach, named as PDRCC (Predict Drug Response in Cancer Cells), the cancer genomic alterations and compound chemical and therapeutic properties were incorporated to determine the chemotherapeutic response in cancer patients. Using the Cancer Cell Line Encyclopedia (CCLE) study as the benchmark dataset, all pharmacogenomics data exhibited their roles in inferring the relationships between cancer cells and drugs. When integrating both genomic resources and compound information, the prediction coverage was significantly increased. The validity of PDRCC was also supported by its effective in uncovering the unknown cell-drug associations with database and literature evidences. It set the stage for clinical testing of novel therapeutic strategies, such as the sensitive association between cancer cell 'A549_LUNG' and compound 'Topotecan'. In conclusion, PDRCC offers the possibility for faster, safer, and cheaper the development of novel anti-cancer therapeutics in the early-stage clinical trails.

Mitochondrial-Associated Cell Death Mechanisms Are Reset to an Embryonic-Like State in Aged Donor-Derived iPS Cells Harboring Chromosomal Aberrations

PubMed Central

Prigione, Alessandro; Hossini, Amir M.; Lichtner, Björn; Serin, Akdes; Fauler, Beatrix; Megges, Matthias; Lurz, Rudi; Lehrach, Hans; Zouboulis, Christos C.

2011-01-01

Somatic cells reprogrammed into induced pluripotent stem cells (iPSCs) acquire features of human embryonic stem cells (hESCs) and thus represent a promising source for cellular therapy of debilitating diseases, such as age-related disorders. However, reprogrammed cell lines have been found to harbor various genomic alterations. In addition, we recently discovered that the mitochondrial DNA of human fibroblasts also undergoes random mutational events upon reprogramming. Aged somatic cells might possess high susceptibility to nuclear and mitochondrial genome instability. Hence, concerns over the oncogenic potential of reprogrammed cells due to the lack of genomic integrity may hinder the applicability of iPSC-based therapies for age-associated conditions. Here, we investigated whether aged reprogrammed cells harboring chromosomal abnormalities show resistance to apoptotic cell death or mitochondrial-associated oxidative stress, both hallmarks of cancer transformation. Four iPSC lines were generated from dermal fibroblasts derived from an 84-year-old woman, representing the oldest human donor so far reprogrammed to pluripotency. Despite the presence of karyotype aberrations, all aged-iPSCs were able to differentiate into neurons, re-establish telomerase activity, and reconfigure mitochondrial ultra-structure and functionality to a hESC-like state. Importantly, aged-iPSCs exhibited high sensitivity to drug-induced apoptosis and low levels of oxidative stress and DNA damage, in a similar fashion as iPSCs derived from young donors and hESCs. Thus, the occurrence of chromosomal abnormalities within aged reprogrammed cells might not be sufficient to over-ride the cellular surveillance machinery and induce malignant transformation through the alteration of mitochondrial-associated cell death. Taken together, we unveiled that cellular reprogramming is capable of reversing aging-related features in somatic cells from a very old subject, despite the presence of genomic alterations. Nevertheless, we believe it will be essential to develop reprogramming protocols capable of safeguarding the integrity of the genome of aged somatic cells, before employing iPSC-based therapy for age-associated disorders. PMID:22110631