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Baver Scott B - - 2008
Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) innervate the hypothalamic suprachiasmatic nucleus (SCN) and the olivary pretectal nucleus (OPN), providing irradiance information for entrainment of circadian rhythms and for stimulating the pupillary light reflex. In this study, mice were used in which the melanopsin gene was replaced with the tau-lacZ ...
de Koning Eelco J P - - 2008
Type 2 diabetes is characterized by progressive beta-cell dysfunction and a reduction in beta-cell mass. Pancreatic islets are a target for adverse effectors such as high concentrations of glucose, pro-inflammatory cytokines and increased free fatty acid concentrations - which are associated with adiposity, insulin resistance and the induction of beta-cell ...
Stukenbrock Hendrik - - 2008
Recently, the serine/threonine kinase glycogen synthase kinase-3 (GSK-3) emerged as a regulator of pancreatic beta cell growth and survival. On the basis of the previous observation that GSK-3 inhibitors like 1-azakenpaullone promote beta cell protection and replication, paullone derivatives were synthesized including 1-aza-, 2-aza-, and 12-oxapaullone scaffolds. In enzymatic assays ...
Hwang Jae-Ho - - 2008
The organic solute and steroid transporter (OST/Ost) is a unique membrane transport protein heterodimer composed of subunits designated alpha and beta, that transports conjugated steroids and prostaglandin E(2) across the plasma membrane. Ost was first identified in the liver of the cartilaginous fish Leucoraja erinacea, the little skate, and subsequently ...
Meier Juris J - - 2008
Little is known about the capacity, mechanisms, or timing of growth in beta-cell mass in humans. We sought to establish if the predominant expansion of beta-cell mass in humans occurs in early childhood and if, as in rodents, this coincides with relatively abundant beta-cell replication. We also sought to establish ...
Meier J J - - 2008
Beta cell deficiency underlies both type 1 and type 2 diabetes, and restoration or replacement of beta cell function is therefore the logical long-term solution to therapy. This review sets out to describe the defects in beta cell mass and function in both forms of diabetes, summarises current understanding of ...
Russ Holger A - - 2008
OBJECTIVE: Expansion of insulin-producing beta-cells from adult human islets could alleviate donor shortage for cell-replacement therapy of diabetes. A major obstacle to development of effective expansion protocols is the rapid loss of beta-cell markers in the cultured cells. Here, we report a genetic cell-lineage tracing approach for following the fate ...
Gess Burkhard - - 2008
N-cadherin and beta-catenin are involved in cell adhesion and cell cycle in tumor cells and neural crest. Both are expressed at key stages of Schwann cell (SC) development, but little is known about their function in the SC lineage. We studied the role of these molecules in adult rat derived ...
Stoika R S - - 2008
AIM: To compare the capability of methotrexate, cisplatin, doxorubicine and vincristine to induce production of the transforming growth factor beta(1) (TGF-beta(1)) in two cell lines - MCF-7 and T47D - of human breast carcinoma, as well as to study sensitivity of these cells to TGF-beta(1) and mentioned anticancer drugs. MATERIALS ...
Howells Lynne M - - 2008
The primary aim of this study was to determine whether combination of the chemopreventive agent indole-3-carbinol (I3C) with oxaliplatin would decrease proliferative index and invasive potential of human colorectal tumour cells. Combination of the agents resulted in a 170-fold decrease in proliferative capacity in SW480 and SW620 cell lines, which ...
Chan Judy Yuet-Wa - - 2008
Hyperglycemia is one of the main causes of oxidative stress in type 2 diabetes mellitus. During hyperglycemia, the increased level of various reducing sugars in the blood enhances the production of reactive oxygen species (ROS) and triggers tissue damage, especially in pancreatic beta-cells. Streptozotocin (STZ) is a diabetogen that causes ...
Homaeigohar S Sh - - 2008
Beta-tricalcium phosphate reinforced high density polyethylene (beta-TCP/HDPE) was prepared to simulate bone composition and to study its capacity to act as bone tissue. This material was produced by replacing the mineral component and collagen soft tissue of the bone with beta-TCP and HDPE, respectively. The biocompatibility of the composite samples ...
Choi, Yang-Soo
Periosteum-derived progenitor cells (PDPCs) were isolated using a fluorescence-activated cell sorter and their chondrogenic potential in biomaterials was investigated for the treatment of defective articular cartilage as a cell therapy. The chondrogenesis of PDPCs was conducted in a thermoreversible gelation polymer (TGP), which is a block copolymer composed of temperature-responsive ...
Jetton Thomas L - - 2008
The physiological mechanisms underlying pancreatic beta-cell mass (BCM) homeostasis are complex and not fully resolved. Here we examined the factors contributing to the increased BCM following a mild glucose infusion (GI) whereby normoglycemia was maintained through 96 h. We used morphometric and immunochemical methods to investigate enhanced beta-cell growth and ...
Takai Noriyuki - - 2008
Beta-hydroxyisovalerylshikonin (beta-HIVS), a compound isolated from the traditional oriental medicinal herb Lithospermum radix, is an ATP non-competitive inhibitor of protein-tyrosine kinases, such as v-Src and EGFR, and it induces apoptosis in some lines of human tumor cells. We investigated the effect of beta-HIVS on three endometrial cancer cell lines, two ...
Oxmann D - - 2008
Endoglin is a cell-surface adhesion protein as well as a coreceptor for transforming growth factor-beta (TGF-beta). It is located on endothelial and few other cells, but also found on certain tumor cells. Brain metastatic breast tumor cells derived from the MDA-MB-231 cell line heavily express endoglin in contrast to the ...
Sato Toshinori - - 2008
Syntheses of oligosaccharides expressed on cells are indispensable for the improvement of the functional analyses of the oligosaccharides and their applications. We are developing saccharide primers for synthesizing oligosaccharides using living cells. In this study, dodecyl 2-acetamido-2-deoxy-beta-D-glucopyranoside (GlcNAc-C12) and dodecyl beta-D-galactopyranosyl-(1-->4)-2-acetamido-2-deoxy-beta-D-glucopyranoside (LacNAc-C12) were examined for their abilities to prime the ...
Beith Jennifer L - - 2008
A relative decrease in beta-cell mass is key in the pathogenesis of type 1 diabetes, type 2 diabetes, and in the failure of transplanted islet grafts. It is now clear that beta-cell duplication plays a dominant role in the regulation of adult beta-cell mass. Therefore, knowledge of the endogenous regulators ...
Al-Awqati Qais - - 2008
The intercalated cell of the cortical collecting tubule exists in two functional and morphologic forms: alpha cells secrete acid, while beta cells secrete HCO(3). It was found that beta cells convert to alpha type when the animal ingests an acid diet or when isolated perfused tubules are exposed to acid. ...
Bai Ji-Zhong - - 2008
Amyloid deposition is a common feature of Alzheimer's disease and type 2 diabetes related to beta-amyloid peptides (betaA) and human amylin (hA), respectively. Both betaA and hA form aggregates and fibrils and kill cultured cells. To investigate whether betaA and hA display peptide-specific toxicity on cultured islet beta-cells, we examined ...
Mziaut Hassan - - 2008
Changes in metabolic demands dynamically regulate the total mass of adult pancreatic beta-cells to adjust insulin secretion and preserve glucose homeostasis. Glucose itself is a major regulator of beta-cell proliferation by inducing insulin secretion and activating beta-cell insulin receptors. Here, we show that islet cell autoantigen 512 (ICA512)/IA-2, an intrinsic ...
Kuo Chan-Yen - - 2008
OBJECTIVE: The hepatitis B virus X protein (HBx) plays critical roles in cell survival via modulation of signaling pathways. In our previous studies, we reported that HBx inhibited the growth of CCL13-HBx-stable cells (Chang-HBx cells) in vitro and tumor formation in vivo in CCL13-HBx-cell-injected nude mice; however, this inhibition mechanism ...
Klöppel Günter - - 2008
Persistent hyperinsulinemic hypoglycemia in adults is usually caused by solitary benign insulinomas. Nesidioblastosis, a term that has been used to designate a functional disorder of the beta cells, is a rare cause of persistent hyperinsulinemic hypoglycemia in adults, but seems to have increased in frequency. The histopathologic criteria for adult ...
Quélard Delphine - - 2008
Collagens contain cryptic polypeptide modules that regulate major cell functions, such as cell proliferation or death. Collagen XVIII (C18) exists as three amino terminal end variants with specific amino terminal polypeptide modules. We investigated the function of the variant 3 of C18 (V3C18) containing a frizzled module (FZC18), which carries ...
Yao Ke - - 2008
BACKGROUND: Epithelial mesenchymal transition (EMT) of postoperative remnants of lens epithelial cells (LECs) can lead to posterior capsule opacification. This study was designed to determine the effect of signaling pathways that contribute to TGF-beta2-mediated EMT in human lens epithelial B-3 cells (HLEB-3 cells). METHODS: The HLEB-3 cells were cultured and ...
Minami Kohtaro - - 2008
Although accumulating evidence indicates that proliferation of pre-existing beta-cells is the major mechanism of the maintenance of postnatal beta-cell mass, new beta-cells can be generated from non-beta-cells under certain conditions in vitro. We have recently shown directly by Cre/loxP-based cell lineage tracing that adult mouse pancreatic acinar cells can be ...
Suckale Jakob - - 2008
The Islets of Langerhans form a nutrient sensing network spread throughout the pancreas. They are tightly connected to the source organ, the intestine, and the target organs--liver, muscle, and fat cells. The expression of a unique set of proteins enables beta cells, the most frequent islet cell type, to detect ...
He Yan - - 2008
OBJECTIVES: Synaptosome-associated protein of 25 kd (SNAP-25) regulates pancreatic islet beta-cell-delayed rectifier K channels (Kv2.1) in addition to insulin exocytosis. Botulinum neurotoxin A (BoNT/A) and E (BoNT/E) cleavage and presumed deletion of SNAP-25 have been used to examine SNAP-25 function. We hypothesized that proteolytic products of SNAP-25 (206 amino acids) ...
Smelt M J - - 2008
Isolation of primary beta cells from other cells within in the pancreatic islets is of importance for many fields of islet research. However, up to now, no satisfactory method has been developed that gained high numbers of viable beta cells, without considerable alpha-cell contamination. In this study, we investigated whether ...
Tisch R - - 2008
Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease in which the insulin producing beta cells are destroyed. The breakdown of beta cell-specific self-tolerance by T cells involves a number of dysregulated events intrinsic and extrinsic to T cells. Herein, we review the key mechanisms that drive beta cell ...
Aldibbiat A - - 2008
Generation of new beta-cells from the adult pancreas or the embryonic stem cells is being pursued by research groups worldwide. Success will be dependent on confirmation of true beta-cell phenotype evidenced by capacity to process and store proinsulin. The aim of these studies was to robustly determine endocrine characteristics of ...
Saudek Frantisek - - 2008
Diabetes is a disorder characterized by beta-cell loss or exhaustion and insulin deficiency. At present, knowledge is lacking on the underlying causes and for the therapeutic recovery of the beta-cell mass. A better understanding of diabetes pathogenesis could be obtained through exact monitoring of the fate of beta-cells under disease ...
Efrat Shimon - - 2008
Ex-vivo generation of human insulin-producing cells is considered a promising approach to providing an abundant source of cells for beta-cell replacement therapy in diabetes. Expansion of adult beta-cells from the limited number of islet donors is an attractive prospect. However, while evidence supports the replicative capacity of both rodent and ...
Jun Hee-Sook - - 2008
Diabetes mellitus results from inadequate mass of insulin-producing pancreatic beta cells. Type 1 diabetes is characterized by absolute loss of beta cells due to autoimmune-mediated destruction. Type 2 diabetes is characterized by relative deficiency of beta cells due to lack of compensation for insulin resistance. Restoration of deficient beta cell ...
Han Seung Jin - - 2008
AIM: We investigated whether rosiglitazone protects beta-cells from glucolipotoxicity directly. METHODS: INS-1 cells were incubated with 25 mM glucose and 0.5 mM palmitate in the absence or presence of 2.5 microM rosiglitazone. We evaluated caspase-3 expression and nuclear DAPI staining. An in vivo study was performed, in which 18-week-old Otsuka ...
Koshkin Vasilij - - 2008
Involvement of the mitochondrial permeability transition (MPT) pore in early stages of lipotoxic stress in the pancreatic beta-cell lines MIN6 and INS-1 was the focus of this study. Both long term (indirect) and acute (direct) effects of fatty acid (FA) application on beta-cell susceptibility to Ca(2+)-induced MPT induction were examined ...
Shimoda Kei - - 2008
The biotransformation of hesperetin by cultured cells of Ipomoea batatas and Eucalyptus perriniana was investigated. Three glycosides, hesperetin 3'-O-beta-D-glucopyranoside (33 microg/g fr. wt of cells), hesperetin 3',7-O-beta-D-diglucopyranoside (217 microg/g fr. wt of cells), and hesperetin 7-O-[6-O-(beta-D-glucopyranosyl)]-beta-d-glucopyranoside (beta-gentiobioside, 22 microg/g fr. wt of cells), together with three hitherto known glycosides, hesperetin ...
Cano David A - - 2008
Several studies have shown that the adult pancreas possesses a limited potential for beta-cell regeneration upon tissue injury. One of the difficulties in studying beta-cell regeneration has been the lack of a robust, synchronized animal model system that would allow controlled regulation of beta-cell loss and subsequent proliferation in adult ...
Hua Hong - - 2007
Inhibitors of DNA binding proteins (Ids) are implicated in the control of proliferation and differentiation. Herein, we tested the hypothesis that Id2 could stimulate proliferation and survival in differentiated pancreatic beta cells. We showed that Id2-enhanced proliferation of a growth-arrested pancreatic beta cell line (BTC-tet). This was mediated by the ...
Racanicchi Leda - - 2007
Beta (beta)-cell replacement represents an attractive approach for the possible cure of type 1 insulin-dependent diabetes mellitus (IDDM). In a search for potential sources of insulin-secreting cells for IDDM substitution therapy, we have focused on the neonatal pig liver, which is putatively enriched in multipotent stem cells. We then isolated ...
Dhawan Sangeeta - - 2007
The elaboration of the pancreas from epithelial buds to the intricate organ requires complex patterning information that controls fundamental cellular processes such as differentiation and proliferation of pancreatic progenitor cells. During pancreatic organogenesis, endocrine cells are generated from a population of pancreatic progenitor cells. The progenitor cells during the early ...
Upadhyaya K R - - 2007
In this communication, we report the efficacy of beta-carotene towards differentiation and apoptosis of leukemia cells. Dose (20 microM) and time dependence (12 h) tests of beta- carotene showed a higher magnitude of decrease (significance p < 0.05) in cell numbers and cell viability in HL-60 cells than U937 cells ...
Shiga Momotoshi - - 2008
The periodontal ligament (PDL) is situated between the tooth root and alveolar bone, thereby supporting the tooth, and is composed of collagen and elastic system fibers. Marfan syndrome type I (MFS1, MIM #154700) is caused by mutations in FBN1 encoding fibrillin-1, which is a major microfibrillar protein of elastic system ...
Wang Xiaoqin - - 2008
Purified native silk fibroin forms beta-sheet-rich, physically cross-linked, hydrogels from aqueous solution, in a process influenced by environmental parameters. Previously we reported gelation times of days to weeks for aqueous native silk protein solutions, with high ionic strength and temperature and low pH responsible for increasing gelation kinetics. Here we ...
Illies Christopher C Rolf Luft Research Center for Diabetes and Endocrinology, Karolinska Institutet, SE-171 76, Stockholm, - - 2007
Inositol pyrophosphates are recognized components of cellular processes that regulate vesicle trafficking, telomere length, and apoptosis. We observed that pancreatic beta cells maintain high basal concentrations of the pyrophosphate diphosphoinositol pentakisphosphate (InsP7 or IP7). Inositol hexakisphosphate kinases (IP6Ks) that can generate IP7 were overexpressed. This overexpression stimulated exocytosis of insulin-containing ...
Alejandro Emilyn U - - 2008
The serine threonine kinase Raf-1 plays a protective role in many cell types, but its function in pancreatic beta-cells has not been elucidated. In the present study, we examined whether primary beta-cells possess Raf-1 and tested the hypothesis that Raf-1 is critical for beta-cell survival. Using reverse transcriptase-PCR, Western blot, ...
Parnaud G - - 2008
AIMS/HYPOTHESIS: The aim of the study was to determine whether purified beta cells can replicate in vitro and whether this is enhanced by extracellular matrix (ECM) and growth factors. METHODS: Human beta cells were purified by FACS by virtue of their high zinc content using Newport Green, and excluding ductal ...
Larsen M O - - 2007
Increased knowledge about beta-cell mass and function is important for our understanding of the pathophysiology of type 2 diabetes (T2DM). The relationship between the two is difficult to study in humans, whereas animal models allow studies of consequences of, for example, reduction of beta-cell mass and induction of obesity and ...
Movassat J - - 2007
Now that reduction in beta-cell mass has been clearly established in humans with type 2 diabetes mellitus (T2D), the debate focuses on the possible mechanisms responsible for decreased beta-cell number. Appropriate inbred rodent models are essential tools for this purpose. The information available from the Goto-Kakizaki (GK) rat, one of ...
Butler Peter C - - 2007
Replication of beta cells is an important source of beta-cell expansion in early childhood. The recent linkage of type 2 diabetes with several transcription factors involved in cell cycle regulation implies that growth of the beta-cell mass in early childhood might be an important determinant of risk for type 2 ...
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