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Guo Qin - - 2009
This study was designed to investigate whether indomethacin and NGX6 synergistically inhibit the growth and invasiveness of human colon cancer cells (HT-29 and SW620) and to elucidate the molecular mechanism of their action. Cell proliferation was assessed by MTT assay. Cell apoptosis was assessed by acridine orange/ethidium bromide staining (AO-EB) ...
Fine Howard A - - 2009
A growing body of evidence suggests that only a small subpopulation of malignant glioma cells have true tumorigenic potential. A study by Peñuelas et al. in this issue of Cancer Cell demonstrates that TGF-beta can stimulate self-renewal and inhibit differentiation in a proportion of these glioma-initiating cells.
Ashihara Eishi - - 2009
PURPOSE: beta-catenin is the downstream effector of the Wnt signaling pathway, and it regulates cell proliferation. beta-catenin overexpression correlates positively with prognosis in several types of malignancies. We herein assessed its effects on growth of multiple myeloma cells using a xenograft model. EXPERIMENTAL DESIGN: We first investigated the expression of ...
Hays Emily - - 2009
Selective knockdown of phosphatase and tensin homolog (PTEN) has been recently shown to increase life long accumulation of bone and its ability to increase osteoblast lifespan. In order to determine how loss of PTEN function affects osteoblast differentiation, we created cell lines with stable knockdown of PTEN expression using short ...
vanZyl Berendine - - 2009
The observation that maternal cells can transfer from mother to child during pregnancy and differentiate into many different tissues including islet beta cells is exciting and intriguing, and to date has generated more questions than answers: Could these genetically distinct maternal cells play a role in the initiation of autoimmune ...
Rashidi Armin - - 2009
The lack of an effective antioxidant system in beta-cells, which renders them susceptible to oxidative stress, is to date without explanation. The particular weakness of beta-cells in females, in both humans and mice, is another unexplained observation. We hypothesise that reactive oxygen species (ROS) in beta-cells, by their negative effect ...
Monti Paolo - - 2009
Autoreactive T cells play a major role in the pathogenesis of type 1 diabetes mellitus (T1DM) and are considered a major target of immunomodulatory strategies aimed at preventing or delaying the disease onset. However, the T-cell response against insulin-producing beta cells is still poorly understood. T cells potentially able to ...
Whitfield J F - - 2009
Dietary Ca(2+) reduces colon cell proliferation and carcinogenesis, but it becomes ineffective or even tumor-promoting during carcinogenesis. It appears that Ca(2+) and the colon cell CaSR together brake the massive cell production in normal colon crypts. The rapid proliferation of the transit-amplifying (TA) progeny of the colon stem cells at ...
Lei Deqiang - - 2009
This study established superparamagnetic iron oxide (SPIO)-labeled nerve growth factor-beta (NGF-beta) gene-modified spinal cord-derived neural stem cells (NSCs). The E14 rat embryonic spinal cord-derived NSCs were isolated and cultured. The cells of the third passage were transfected with plasmid pcDNA3-hNGFbeta by using FuGENE HD transfection reagent. The expression of NGF-beta ...
Kim Dohee - - 2009
alpha- and beta-Catenin link cadherins to the actin-based cytoskeleton at adherens junctions and regulate cell-cell adhesion. Although roles of cadherins and canonical Wnt-/beta-catenin-signaling in osteoblastic differentiation have been extensively studied, the role of alpha-catenin is not known. Murine embryonic mesenchymal stem cells, C3H10T1/2 cells, were transduced with retrovirus encoding alpha-catenin ...
Borg Jörgen - - 2009
Lipids have been shown to play a dual role in pancreatic beta-cells: a lipid-derived signal appears to be necessary for glucose-stimulated insulin secretion, whereas lipid accumulation causes impaired insulin secretion and apoptosis. The ability of the protein perilipin to regulate lipolysis prompted an investigation of the presence of perilipin in ...
Reinbothe Thomas M - - 2009
Nicotinamide adenine dinucleotide phosphate (NADPH) enhances Ca(2+)-induced exocytosis in pancreatic beta-cells, an effect suggested to involve the cytosolic redox protein glutaredoxin-1 (GRX-1). We here detail the role of GRX-1 in NADPH-stimulated beta-cell exocytosis and glucose-stimulated insulin secretion. Silencing of GRX-1 by RNA interference reduced glucose-stimulated insulin secretion in both clonal ...
Du Wei - - 2009
Stabilized F-actin structures have been shown to be detrimental to both mammalian and yeast cells. In yeast, stabilization of actin caused by addition of jasplakinolide, by point mutations in the act1 gene, or by deletion of certain genes that regulate F-actin leads to cell death with hallmarks of apoptosis. In ...
Joo Mee - - 2009
Paneth cell differentiation may occur in colonic epithelial neoplasms. However, its significance and mechanism of development remains unclear. Human defensin 5 is a specific marker of Paneth cells and has been shown to represent one of the target genes of the Apc/beta-catenin/Tcf pathway. The aim of this study was to ...
Sahin Mustafa - - 2009
Previous studies show that hypogonadism is associated with a higher incidence of type 2 diabetes in male patients, in contrast, hyperandrogenism is associated with higher risk of type 2 diabetes in women. We hypothesized that there androgens may have negative effects on beta-cell functions. Androgen receptors may be important for ...
Hamada Suirin - - 2009
Components of insulin/IGF-1 receptor-mediated signaling pathways in pancreatic beta-cells have been implicated in the development of diabetes, in part through the regulation of beta-cell mass in vivo. Studies in vitro have shown that the protein Ras homolog enriched in brain (Rheb) plays a key role as a positive upstream regulator ...
Yang Qing - - 2009
Successful embryo implantation depends on the ability of the trophoblast cells to invade the endometrium and the receptivity of the endometrium. Unlike tumor invasion, trophoblast invasion is spatio-temporaly restricted. Transforming growth factor (TGF)-beta is a key inhibitory factor in the invasion of early trophoblast cells. Smad ubiquitination regulatory factor 2 ...
Hoben Gwendolyn M - - 2009
The successful differentiation of human embryonic stem cells (hESCs) to fibrochondrocyte-like cells and characterization of these differentiated cells is a critical step toward tissue engineering of musculoskeletal fibrocartilages (e.g., knee meniscus, temporomandibular joint disc, and intervertebral disc). In this study, growth factors and primary cell cocultures were applied to hESC ...
Silva Amelia M - - 2009
Given the growing interest in porcine islets as model tissue for studying the pathogenesis of human diabetes mellitus and its treatment by transplantation, we investigated stimulus-exocytosis coupling in single porcine beta-cells using patch clamp electrophysiology, Ca2+ imaging, capacitance tracking and amperometry. We establish that porcine beta-cells display several features prominently ...
Brennand Kristen - - 2009
The beta-cells of the pancreas are responsible for insulin production and their destruction results in type I diabetes. beta-cell maintenance, growth and regenerative repair is thought to occur predominately, if not exclusively, through the replication of existing beta-cells, not via an adult stem cell. It was recently found that all ...
Karaca M - - 2009
In the adult, the pancreatic beta-cell mass adapts insulin secretion to meet long-term changes in insulin demand and, in particular, in the presence of insulin resistance that is either physiological, such as pregnancy, or pathophysiological, such as obesity. The failure of beta cells to compensate for insulin resistance is a ...
Jovanović M - - 2009
Interleukin-6 (IL-6) is present in human endometrium throughout menstrual cycle and in pregnancy. Trophoblast also expresses IL-6. IL-6R and its associated signal transducer gp130 were found in trophoblast as well. IL-6 is generally assumed to be relevant for trophoblast invasion. This study was undertaken to determine influence of endogenous and ...
Nishimura Takeshi - - 2009
Aim: Transforming growth factor-beta (TGF-beta) has dual activity in tumor cells. We studied the effect of TGF-beta on tumor-initiating cells (TICs), which are similar in self-renewal and differentiation features to normal adult stem cells. Methods: We used side population (SP) cells that exclude DNA binding dye Hoechst 33342 to obtain ...
Saitoh Masao - - 2009
The epithelial-mesenchymal transition (EMT), a crucial event in cancer progression and embryonic development, is induced by transforming growth factor (TGF)-beta. Expression of E-cadherin, a representative epithelial marker, is repressed through transcriptional reduction by TGF-beta. Here, we show that endocytosis of cell surface E-cadherin during EMT induced by TGF-beta and during ...
Zemke Anna C - - 2009
Signaling by Wnt/beta-catenin regulates self-renewal of tissue stem cells in the gut and, when activated in the embryonic bronchiolar epithelium, leads to stem cell expansion. We have used transgenic and cell type-specific knockout strategies to determine roles for beta-catenin-regulated gene expression in normal maintenance and repair of the bronchiolar epithelium. ...
Makioka Kouki - - 2009
OBJECTIVE: Autophagy, the intracellular breakdown system for proteins and some organelles, is considered to be important in neurodegenerative disease. Recent reports suggest that autophagy plays an important role in Alzheimer's disease pathogenesis and autophagic vacuoles (AVs) may be sites of amyloid beta protein (Abeta) generation. We attempted to determine if ...
Tian Dan - - 2009
Cigarette smoke is known to have various injurious and cytotoxic effects on alveolar epithelial cells. However, the mechanism about the effects caused by cigarette smoke on alveolar epithelial cells remains unclear. In the present study, we first validated that cigarette smoke extract (CSE) impaired the viability of alveolar epithelial cells ...
Salem L Belhadj - - 2009
Cyclodextrins (CDs) are promising solubility enhancers for inhaled drug delivery. However, they have dose-dependent effects on the respiratory epithelium, which may have advantages for permeability enhancement but also gives rise to safety concerns. In this study, the methyl thiazol tetrazolium (MTT) assay was used to compare a new sparingly methylated ...
Mukhi Sandeep S Department of Embryology, Carnegie Institution, 3520 San Martin Drive, Baltimore, MD 21218, - - 2009
Insulin-producing beta-cells are present as single cells or in small clusters distributed throughout the pancreas of the Xenopus laevis tadpole. During metamorphic climax when the exocrine pancreas dedifferentiates to progenitor cells, the beta-cells undergo two changes. Insulin mRNA is down regulated at the beginning of metamorphic climax (NF62) and reexpressed ...
Bernardo Andreia S - - 2009
Embryonic stem (ES) cells represent a possible source of islet tissue for the treatment of diabetes. Achieving this goal will require a detailed understanding of how the transcription factor cascade initiated by the homeodomain transcription factor Pdx1 culminates in pancreatic beta-cell development. Here we describe a genetic approach that enables ...
Baeyens Luc - - 2009
BACKGROUND & AIMS: Exocrine acinar cells in the pancreas are highly differentiated cells that retain a remarkable degree of plasticity. After isolation and an initial phase of dedifferentiation in vitro, rodent acinar cells can convert to endocrine beta-cells when cultured in the presence of appropriate factors. The mechanisms regulating this ...
Nagaya Masaki - - 2009
Transdifferentiation of cells from a patient's own liver into pancreatic beta-cells could be useful for beta-cell replacement. We hypothesized that intrahepatic biliary epithelial cells (IHBECs) could become a new source of insulin-producing cells. IHBECs isolated from adult mice were expanded using our novel culture method termed, collagen-embedded floating culture method ...
Wang Weidong - - 2009
To identify small molecules that can induce beta-cell replication, a large chemical library was screened for proliferation of growth-arrested, reversibly immortalized mouse beta cells by using an automated high-throughput screening platform. A number of structurally diverse, active compounds were identified, including phorbol esters, which likely act through protein kinase C, ...
Rafacho Alex - - 2009
Activation of insulin signaling and cell cycle intermediates is required for adult beta-cell proliferation. Here, we report a model to study beta-cell proliferation in living rats by administering three different doses of dexamethasone (0.1, 0.5, and 1.0 mg/kg ip, DEX 0.1, DEX 0.5, and DEX 1.0, respectively) for 5 days. ...
Maes Emmanuel - - 2009
The yeast Candida albicans is an opportunistic pathogen that causes infections in immunocompromised individuals with a high morbidity and mortality levels. Recognition of yeasts by host cells is directly mediated by cell wall components of the yeast, including a wide range of abundantly expressed glycoconjugates. Of particular interest in C. ...
Green J Angelo - - 2009
The integrin beta(1) cytoplasmic domain (tail) serves as a scaffold for numerous intracellular proteins. The mechanisms by which the tail coordinates these proteins to facilitate extracellular matrix assembly and cell spreading are not clear. This study demonstrates that the beta(1) cytoplasmic domain can regulate cell spreading on fibronectin and fibronectin ...
Balcazar Norman - - 2009
Growth factors, insulin signaling, and nutrients are important regulators of beta-cell mass and function. The events linking these signals to the regulation of beta-cell mass are not completely understood. The mTOR pathway integrates signals from growth factors and nutrients. Here, we evaluated the role of the mTOR/raptor (mTORC1) signaling in ...
Yang Pu - - 2009
AIMS: Clear differences of biological function between very low density lipoprotein receptor (VLDLR) types I and II have not been defined. The purpose of this study is to characterize VLDLR activities during cell proliferation and migration using adenocarcinoma SGC7901 cells. MAIN METHODS: Western blotting was used to test protein expression. ...
Johnson James D - - 2009
Type 2 diabetes occurs when the endocrine pancreas can no longer secrete enough insulin to maintain glucose and lipid homeostasis. This is likely due to cumulative defects in beta-cell fate and function, as well as insulin resistance. A number of recent studies, including ones from our group, have used unbiased ...
Yang Xiao-Di - - 2009
Biopolyesters of polyhydroxyalkanoates (PHAs), including poly-3-hydroxybutyrate (PHB), co-polyester of 3-hydroxybutyrate and 4-hydroxybutyrate (P3HB4HB), and co-polyester of 3-hydroxybutyrate and 3-hydroxyhexanoate (PHBHHx) have been well investigated for their biocompatibility. For in vivo application, it is very important that the degradation products of PHAs, especially the oligomers, are not harmful to the cells ...
Guerra Mar??a Montserrat - - 2009
Increasing evidence suggests that the hypophyseal pars tuberalis (PT) plays a key role in the transduction of light/dark (melatonin) information to the endocrine system. It has been shown that PT-specific cells express melatonin receptors and thyrotropin hormone (TSH) subunits. However, these cells do not resemble thyrotrophs or any other of ...
Boo Jung H - - 2009
Presenilin (PS) is involved in many cellular events under physiological and pathological conditions. Previous reports have revealed that PS deficiency results in hyperproliferation and resistance to apoptotic cell death. In the present study, we investigated the effects of PS on beta-catenin and cell mortality during serum deprivation. Under these conditions, ...
Lin Peng - - 2009
Diabetes mellitus is a metabolic disorder characterized by elevated blood sugar and progressive failure of insulin-producing beta-cells. Persistent hyperglycemia and blood sugar fluctuation are two general phenomena in diabetic patients, and both of them can result in an increased frequency of beta-cell apoptosis. Therefore, rescuing pancreatic beta-cells from glucotoxicity-induced beta-cell ...
Pajak Beata - - 2009
Herein we demonstrate that PC12 cells overexpress human amyloid beta precursor protein bearing double Swedish mutation(AbetaPPsw), showing the phenotype characteristic for Alzheimer's disease (AD). Examination of cells at ultrastructural level revealed the intracellular presence of peptide aggregates. Furthermore, autophagy induction was found to be a hallmark of amyloid beta-induced cytotoxicity. ...
Song Woo-Jin - - 2009
The two main forms of human diabetes mellitus (DM) are characterized by an absolute (type 1) and a relative (type 2) reduction in functional insulin-producing beta cell mass in the pancreas. Type 1 DM results from autoimmune assault of beta cells, and type 2 from the failure of pancreatic beta ...
Feng Daorong - - 2009
BACKGROUND: A deficiency in Perk (EIF2AK3) causes multiple neonatal defects in humans known as the Wolcott Rallison syndrome. Perk KO mice exhibit the same array of defects including permanent neonatal diabetes (PND). PND in mice was previously shown by us to be due to a decrease in beta cell proliferation ...
Marselli Lorella - - 2009
Human beta-cell gene profiling is a powerful tool for understanding beta-cell biology in normal and pathological conditions. The assessment is complicated when isolated islets are studied because of contamination by non-beta-cells and the exposure to the trauma of isolation that causes changes in gene expression. These limitations can be overcome ...
Helleboid-Chapman Audrey - - 2009
Apolipoprotein A-V is an important determinant of plasma triglyceride level in both humans and mice. This study showed the physiological impact of apoA-V on insulin secretion in rat pancreatic beta-cells (INS-1 cells). In order to precise the mechanism of action, binding experiments coupled to mass spectrometry were performed to identify ...
Poon Raymond - - 2009
BACKGROUND: beta-catenin and transforming growth factor beta signaling are activated in fibroblasts during wound healing. Both signaling pathways positively regulate fibroblast proliferation during this reparative process, and the effect of transforming growth factor beta is partially mediated by beta-catenin. Other cellular processes, such as cell motility and the induction of ...
Yeh Yi-Chun - - 2009
Upregulation and overexpression of discoidin domain receptor 1 (DDR1) have been implied in the regulation of kidney development and progression of cancers. Our previous studies with Mardin-Darby canine kidney (MDCK) cells showed that overexpression of DDR1 inhibited cell spreading, whereas dominant negative DDR1 promoted cell spreading on collagen-coated dish. Cell ...
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