26 results on '"Catherine A. Priest"'
Search Results
2. Safety of direct injection of oligodendrocyte progenitor cells into the spinal cord of uninjured Göttingen minipigs
- Author
-
Richard G. Fessler, R David Fessler, Charles Y. Liu, Edward D. Wirth, Catherine A. Priest, Stephen McKenna, and Jane S. Lebkowski
- Subjects
Pathology ,medicine.medical_specialty ,business.industry ,Oligodendrocyte progenitor ,Balanced salt solution ,Inflammation ,General Medicine ,medicine.disease ,Spinal cord ,Tumor formation ,medicine.anatomical_structure ,medicine ,Stem cell ,medicine.symptom ,business ,Spinal cord injury ,Progenitor - Abstract
OBJECTIVE This study was conducted as a final proof-of-safety direct injection of oligodendrocyte progenitor cells into the uninjured spinal cord prior to translation to the human clinical trials. METHODS In this study, 107 oligodendrocyte progenitor cells (LCTOPC1, also known as AST-OPC1 and GRNOPC1) in 50-μL suspension were injected directly into the uninjured spinal cords of 8 immunosuppressed Göttingen minipigs using a specially designed stereotactic delivery device. Four additional Göttingen minipigs were given Hanks’ Balanced Salt Solution and acted as the control group. RESULTS Cell survival and no evidence of histological damage, abnormal inflammation, microbiological or immunological abnormalities, tumor formation, or unexpected morbidity or mortality were demonstrated. CONCLUSIONS These data strongly support the safety of intraparenchymal injection of LCTOPC1 into the spinal cord using a model anatomically similar to that of the human spinal cord. Furthermore, this research provides guidance for future clinical interventions, including mechanisms for precise positioning and anticipated volumes of biological payloads that can be safely delivered directly into uninjured portions of the spinal cord.
- Published
- 2020
3. Human Embryonic Stem Cell-Derived Oligodendrocyte Progenitor Cells: Preclinical Efficacy and Safety in Cervical Spinal Cord Injury
- Author
-
Catherine A. Priest, Edward D. Wirth, Jane S. Lebkowski, Jerrod Denham, and Nathan C. Manley
- Subjects
0301 basic medicine ,Oncology ,medicine.medical_specialty ,Human Embryonic Stem Cells ,Regenerative medicine ,03 medical and health sciences ,0302 clinical medicine ,Neural Stem Cells ,Translational Research Articles and Reviews ,Cell Movement ,Tissue Engineering and Regenerative Medicine ,Internal medicine ,medicine ,Animals ,Humans ,Spinal Cord Injury ,Spinal cord injury ,Spinal Cord Injuries ,Embryonic Stem Cells ,Cervical spinal cord injury ,Oligodendrocyte progenitor cell ,Human embryonic stem cell ,business.industry ,Cell Biology ,General Medicine ,medicine.disease ,Spinal cord ,Preclinical ,Neural stem cell ,Rats ,Surgery ,Clinical trial ,Oligodendroglia ,030104 developmental biology ,Allodynia ,medicine.anatomical_structure ,Cervical Vertebrae ,Female ,Oligodendrocytes Precursor cells ,medicine.symptom ,Stem cell ,business ,030217 neurology & neurosurgery ,Stem Cell Transplantation ,Developmental Biology ,Cervical vertebrae - Abstract
Cervical spinal cord injury (SCI) remains an important research focus for regenerative medicine given the potential for severe functional deficits and the current lack of treatment options to augment neurological recovery. We recently reported the preclinical safety data of a human embryonic cell-derived oligodendrocyte progenitor cell (OPC) therapy that supported initiation of a phase I clinical trial for patients with sensorimotor complete thoracic SCI. To support the clinical use of this OPC therapy for cervical injuries, we conducted preclinical efficacy and safety testing of the OPCs in a nude rat model of cervical SCI. Using the automated TreadScan system to track motor behavioral recovery, we found that OPCs significantly improved locomotor performance when administered directly into the cervical spinal cord 1 week after injury, and that this functional improvement was associated with reduced parenchymal cavitation and increased sparing of myelinated axons within the injury site. Based on large scale biodistribution and toxicology studies, we show that OPC migration is limited to the spinal cord and brainstem and did not cause any adverse clinical observations, toxicities, allodynia, or tumors. In combination with previously published efficacy and safety data, the results presented here supported initiation of a phase I/IIa clinical trial in the U.S. for patients with sensorimotor complete cervical SCI.
- Published
- 2017
4. Preclinical safety of human embryonic stem cell-derived oligodendrocyte progenitors supporting clinical trials in spinal cord injury
- Author
-
Edward D. Wirth, Jerrod Denham, Catherine A. Priest, Nathan C. Manley, and Jane S. Lebkowski
- Subjects
Embryology ,Pathology ,medicine.medical_specialty ,Human Embryonic Stem Cells ,Population ,Biomedical Engineering ,Mice, Nude ,Bioinformatics ,digestive system ,Cell therapy ,Mice ,In vivo ,medicine ,Animals ,Humans ,Progenitor cell ,education ,Spinal cord injury ,Spinal Cord Injuries ,education.field_of_study ,business.industry ,medicine.disease ,Embryonic stem cell ,digestive system diseases ,Oligodendrocyte ,Oligodendroglia ,medicine.anatomical_structure ,Allodynia ,Heterografts ,medicine.symptom ,business ,Stem Cell Transplantation - Abstract
Aim: To characterize the preclinical safety profile of a human embryonic stem cell-derived oligodendrocyte progenitor cell therapy product (AST-OPC1) in support of its use as a treatment for spinal cord injury (SCI). Materials & methods: The phenotype and functional capacity of AST-OPC1 was characterized in vitro and in vivo. Safety and toxicology of AST-OPC1 administration was assessed in rodent models of thoracic SCI. Results: These results identify AST-OPC1 as an early-stage oligodendrocyte progenitor population capable of promoting neurite outgrowth in vitro and myelination in vivo. AST-OPC1 administration did not cause any adverse clinical observations, toxicities, allodynia or tumors. Conclusion: These results supported initiation of a Phase I clinical trial in patients with sensorimotor complete thoracic SCI.
- Published
- 2015
5. Proceedings: Moving Toward Cell-Based Therapies for Heart Disease
- Author
-
Ingrid W. Caras, Lisa C. Kadyk, Neil Littman, Catherine A. Priest, and Lila R. Collins
- Subjects
Heart Failure ,Oncology ,medicine.medical_specialty ,Heart disease ,business.industry ,Myocardium ,Cell- and Tissue-Based Therapy ,Myocardial Infarction ,Cell Biology ,General Medicine ,Regenerative Medicine ,medicine.disease ,Internal medicine ,medicine ,Humans ,business ,Stem Cell Transplantation ,Perspectives ,Developmental Biology ,Cell based - Abstract
Summary Heart disease due to myocardial infarction and the ensuing heart failure represent a major unmet medical need. Approved treatments do not prevent loss of cardiac muscle or reduce scar formation, both of which weaken heart function. Cell-based therapies currently being investigated both preclinically and clinically have the potential to address these underlying problems either by actually replacing lost tissue or by supplying paracrine growth factors that may have multiple beneficial effects such as reduction of inflammation, increase of blood supply, improvement in cell survival, and reduction of scar size. The best cell types, stage of disease to target, and delivery method to improve heart function are currently unclear. The California Institute for Regenerative Medicine supports multiple different cell-therapy strategies for heart disease, offering hope that improved treatments will be available for patients in the future. Significance Heart attack and the heart failure that often follows represent an enormous financial burden and unmet medical need. Cell therapy is being actively explored to improve cardiac function for both of these forms of heart disease. The cell therapy and tissue engineering efforts supported by the California Institute for Regenerative Medicine to improve heart function after a myocardial infarction and during heart failure span a variety of novel approaches, many of which go beyond current approaches in clinical trials.
- Published
- 2015
6. Proceedings: Cell Therapies for Parkinson's Disease From Discovery to Clinic
- Author
-
Geoffrey P. Lomax, Catherine A. Priest, Rosa Canet-Aviles, and Ellen G. Feigal
- Subjects
medicine.medical_specialty ,Parkinson's disease ,business.industry ,Alternative medicine ,Cell replacement ,Cell Biology ,General Medicine ,Disease ,medicine.disease ,Regenerative medicine ,Meeting Reports ,Clinical trial ,Medicine ,Stem cell ,business ,Intensive care medicine ,Developmental Biology - Abstract
In March 2013, the California Institute for Regenerative Medicine, in collaboration with the NIH Center for Regenerative Medicine, held a 2-day workshop on cell therapies for Parkinson's disease (PD), with the goals of reviewing the state of stem cell research for the treatment of PD and discussing and refining the approach and the appropriate patient populations in which to plan and conduct new clinical trials using stem cell-based therapies for PD. Workshop participants identified priorities for research, development, and funding; discussed existing resources and initiatives; and outlined a path to the clinic for a stem cell-based therapy for PD. A consensus emerged among participants that the development of cell replacement therapies for PD using stem cell-derived products could potentially offer substantial benefits to patients. As with all stem cell-based therapeutic approaches, however, there are many issues yet to be resolved regarding the safety, efficacy, and methodology of transplanting cell therapies into patients. Workshop participants agreed that designing an effective stem cell-based therapy for PD will require further research and development in several key areas. This paper summarizes the meeting.
- Published
- 2014
7. Estrogen Actions in the Brain: A Symposium to Honor the Contributions of Roger A. Gorski. November 6, 1998. University of California, Los Angeles
- Author
-
Paul E. Micevych and Catherine A. Priest
- Subjects
Pharmacology ,Neuropsychology and Physiological Psychology ,Estrogen ,medicine.drug_class ,Anthropology ,Honor ,medicine ,Environmental ethics ,Sociology - Published
- 2006
8. GABAB receptor expression and function in olfactory receptor neuron axon growth
- Author
-
Catherine A. Priest and Adam C. Puche
- Subjects
Male ,Baclofen ,Time Factors ,Neurite ,Olfactory receptor neuron ,Growth Cones ,In Vitro Techniques ,GABAB receptor ,Biology ,Olfactory Receptor Neurons ,Mice ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Organophosphorus Compounds ,Olfactory Mucosa ,Pregnancy ,medicine ,Animals ,Drug Interactions ,Neurotransmitter ,Receptor ,GABA Agonists ,Cells, Cultured ,Analysis of Variance ,Olfactory receptor ,Glutamate Decarboxylase ,General Neuroscience ,respiratory system ,Embryo, Mammalian ,Immunohistochemistry ,Olfactory Bulb ,Axons ,Olfactory bulb ,medicine.anatomical_structure ,Animals, Newborn ,Gene Expression Regulation ,Receptors, GABA-B ,nervous system ,chemistry ,GABA-B Receptor Agonists ,Female ,sense organs ,GABA-B Receptor Antagonists ,Neuroscience - Abstract
Neurotransmitters have been implicated in regulating growth cone motility and guidance in the developing nervous system. Anatomical and electrophysiological studies show the presence of functional GABAB receptors on adult olfactory receptor neuron (ORN) nerve terminals. Using antisera against the GABAB R1a/b receptor isoforms we show that developing mouse olfactory receptor neurons express GABAB receptors from embryonic day 14 through to adulthood. GABAB receptors are present on axon growth cones from both dissociated ORNs and olfactory epithelial explants. Neurons in the olfactory bulb begin to express glutamic acid decarboxylase (GAD), the synthetic enzyme for GABA, from E16 through to adulthood. When dissociated ORNs were cultured in the presence of the GABAB receptor agonists, baclofen or SKF97541, neurite outgrowth was significantly reduced. Concurrent treatment of the neurons with baclofen and the GABAB receptor antagonist CGP54626 prevented the inhibitory effects of baclofen on ORN neurite outgrowth. These results show that growing ORN axons express GABAB receptors and are sensitive to the effects of GABAB receptor activation. Thus, ORNs in vivo may detect GABA release from juxtaglomerular cells as they enter the glomerular layer and use this as a signal to limit their outgrowth and find synaptic targets in regeneration and development.
- Published
- 2004
9. Targeted Deletion of the Vgf Gene Indicates that the Encoded Secretory Peptide Precursor Plays a Novel Role in the Regulation of Energy Balance
- Author
-
Tooru M. Mizuno, Paul F. Good, James L. Roberts, Robert C McEvoy, Seung Hahm, Bonnie Peng, John E. Pintar, Kevin Kelley, Christine A. Kozak, T. John Wu, Joseph S. Takahashi, Catherine A. Priest, Charles V. Mobbs, Carol N. Boozer, Jonathan P. Wisor, and Stephen R.J. Salton
- Subjects
Leptin ,Male ,Circadian clock ,Gene Expression ,Thyrotropin ,Poison control ,Energy homeostasis ,Mice ,Catecholamines ,Homeostasis ,In Situ Hybridization ,Mice, Knockout ,Neurons ,General Neuroscience ,digestive, oral, and skin physiology ,Fasting ,Neuropeptide Y receptor ,Circadian Rhythm ,Aggression ,Phenotype ,Hypothalamus ,Pituitary Gland ,Knockout mouse ,Female ,hormones, hormone substitutes, and hormone antagonists ,medicine.medical_specialty ,Neuroscience(all) ,Biology ,Mammary Glands, Animal ,Oxygen Consumption ,Proopiomelanocortin ,Internal medicine ,medicine ,Animals ,Nerve Growth Factors ,RNA, Messenger ,Protein Precursors ,Body Weight ,Neuropeptides ,Ovary ,Arcuate Nucleus of Hypothalamus ,Proteins ,Mice, Inbred C57BL ,Fertility ,Endocrinology ,biology.protein ,Energy Metabolism ,Gene Deletion ,Gonadotropins - Abstract
To determine the function of VGF, a secreted polypeptide that is synthesized by neurons, is abundant in the hypothalamus, and is regulated in the brain by electrical activity, injury, and the circadian clock, we generated knockout mice lacking Vgf. Homozygous mutants are small, hypermetabolic, hyperactive, and infertile, with markedly reduced leptin levels and fat stores and altered hypothalamic proopiomelanocortin (POMC), neuropeptide Y (NPY), and agouti-related peptide (AGRP) expression. Furthermore, VGF mRNA synthesis is induced in the hypothalamic arcuate nuclei of fasted normal mice. VGF therefore plays a critical role in the regulation of energy homeostasis, suggesting that the study of lean VGF mutant mice may provide insight into wasting disorders and, moreover, that pharmacological antagonism of VGF action(s) might constitute the basis for treatment of obesity.
- Published
- 1999
10. Hypothalamic Pro-Opiomelanocortin mRNA Is Reduced By Fasting in ob/ob and db/db Mice, but Is Stimulated by Leptin
- Author
-
James L. Roberts, Steven P. Kleopoulos, Catherine A. Priest, Tooru M. Mizuno, Charles V. Mobbs, and Hugo Bergen
- Subjects
endocrine system ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Leptin ,digestive, oral, and skin physiology ,Prohormone ,Biology ,Neuropeptide Y receptor ,Endocrinology ,medicine.anatomical_structure ,Central melanocortin system ,Hypothalamus ,Internal medicine ,Gene expression ,Internal Medicine ,medicine ,Melanocortin ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,Hormone - Abstract
Reduction in the activity of the α-melanocyte-stimulating hormone (α-MSH) system causes obesity, and infusions of α-MSH can produce satiety, raising the possibility that α-MSH may mediate physiological satiety signals. Since α-MSH is coded for by the pro-opiomelanocortin (POMC) gene, we examined if POMC gene expression would be inhibited by fasting in normal mice or in models of obesity characterized by leptin insufficiency (ob/ob) or leptin insensitivity (db/db). In wild-type mice, hypothalamic POMC mRNA was decreased >60% after a 2-day fast and was positively correlated with leptin mRNA. Similarly, compared with controls, POMC mRNA was decreased by at least 60% in both db/db and ob/ob mice. POMC mRNA was negatively correlated with both neuropeptide Y (NPY) and melanin-concentrating hormone (MCH) mRNA. Finally, treatment of both male and female ob/ob mice with leptin stimulated hypothalamic POMC mRNA by about threefold. These results suggest that impairment in production, processing, or responsiveness to α-MSH may be a common feature of obesity and that hypothalamic POMC neurons, stimulated by leptin, may constitute a link between leptin and the melanocortin system.
- Published
- 1998
11. Estrogen and Stress Interact to Regulate the Hypothalamic Expression of a Human Proenkephalin Promoter‐β‐Galactosidase Fusion Gene in a Site‐Specific and Sex‐Specific Manner
- Author
-
David Borsook, Donald W. Pfaff, and Catherine A. Priest
- Subjects
Male ,endocrine system ,medicine.medical_specialty ,medicine.drug_class ,Ovariectomy ,Recombinant Fusion Proteins ,Endocrinology, Diabetes and Metabolism ,Transgene ,medicine.medical_treatment ,Intraperitoneal injection ,Hypothalamus ,Hypothalamus, Middle ,Biology ,Mice ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Endocrinology ,Stress, Physiological ,Internal medicine ,medicine ,Animals ,Humans ,RNA, Messenger ,Protein Precursors ,Promoter Regions, Genetic ,Sex Characteristics ,Estradiol ,Endocrine and Autonomic Systems ,Enkephalins ,beta-Galactosidase ,Hypertonic saline ,Proenkephalin ,Gene Expression Regulation ,chemistry ,Estrogen ,Estradiol benzoate ,Ovariectomized rat ,Female ,Paraventricular Hypothalamic Nucleus - Abstract
Gonadal steroids and physiological stressors affect the regulation of proenkephalin (PPE) gene expression in the paraventricular (PVN) and ventromedial (VMH) hypothalamic nuclei. To examine the effects of these modulators at the cellular level, the current study utilized a transgenic mouse line that expresses a human proenkephalin promoter/bacterial beta-galactosidase fusion gene (ENK-1). Previous studies have demonstrated that the regulatory sequences included in this transgene are sufficient to support appropriate transcriptional regulation of the reported gene in the PVN of male ENK-1 mice in response to stress. The present experimental paradigm was designed to examine possible interactions of sex and circulating estrogen levels with the opioid responses to acute systemic stressors, an intraperitoneal injection of hypertonic (1.5 M) or isotonic (0.15 M) saline. Adult ENK-1 mice were gonadally intact, gonadectomized, or 21 days postpartum. Forty-eight hours before perfusion, castrated males and ovariectomized females received either 10 micrograms estradiol benzoate or oil vehicle and 4 animals per group received no further treatment. Six h before perfusion, remaining animals received a single intraperitoneal injection of either hypertonic or isotonic saline. Tissues were sectioned through the hypothalamus and processed for X-gal histochemistry. In the VMH of ovariectomized females that received isotonic saline, estrogen significantly elevated transgene expression. This effect was not seen in females that only received estrogen or in those that received the severe systemic stressor of a injection of hypertonic saline. Estrogen and stress did not interact to elevate transgene expression in the VMH of males. A different pattern of expression was observed in the PVN; injection of hypertonic saline induced transgene expression only in gonadally intact males and in castrated males given estrogen. These findings demonstrate that stress and estrogen have sex-specific and site-specific regulatory effects on the expression of a PPE promoter transgene in hypothalamic neurons.
- Published
- 1997
12. Estrogen regulates preproenkephalin-A mRNA levels in the rat ventromedial nucleus: temporal and cellular aspects
- Author
-
Clair B. Eckersell, Paul E. Micevych, and Catherine A. Priest
- Subjects
medicine.medical_specialty ,medicine.drug_class ,Hypothalamus ,Neuropeptide ,Cell Count ,Biology ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Arcuate nucleus ,Internal medicine ,medicine ,Animals ,RNA, Messenger ,Protein Precursors ,Molecular Biology ,In Situ Hybridization ,Endogenous opioid ,Behavior, Animal ,Arcuate Nucleus of Hypothalamus ,Estrogens ,Enkephalins ,Lordosis behavior ,Rats ,Ventromedial nucleus of the hypothalamus ,Endocrinology ,chemistry ,Estrogen ,Estradiol benzoate ,Female ,hormones, hormone substitutes, and hormone antagonists - Abstract
Numerous studies suggest that the ventromedial nucleus of the hypothalamus is a primary locus of control for reproductive behavior in the female rat. The display of lordosis behavior is estrogen dependent and its regulation appears to involve the activity of endogenous opioid circuits in the mediobasal hypothalamus and brainstem. Hypothalamic levels of preproenkephalin-A mRNA and the neuropeptide which it encodes, methionine-enkephalin, are dramatically up-regulated by estrogen. To characterize the temporal and cellular aspects of the effect of an acute exposure to estrogen on preproenkephalin-A mRNA levels in the ventromedial nucleus and arcuate nucleus of the hypothalamus, ovariectomized female rats were injected with 50 μg estradiol benzoate and used for quantitative in situ hybridization histochemistry of preproenkephalin-A mRNA. In the ventromedial nucleus, estrogen treatment caused a biphasic increase in the number of preproenkephalin-A mRNA cells. Maximal numbers of cells expressing preproenkephalin-A mRNA were observed at 1 and 48 h after estrogen injection. At 4 and 96 h after estrogen injection, the numbers of preproenkephalin-A mRNA cells were similar to that which was seen in the ovariectomized female. The induction of preproenkephalin-A mRNA expression in cells of the arcuate nucleus followed a similar pattern that peaked 48 h after exposure to estrogen. Levels of preproenkephalin-A mRNA per cell did not change in either nucleus as a function of estrogen treatment. Thus, acute estrogen treatment induces expression of preproenkephalin-A mRNA in populations of cells in theventromedial hypothalamus and arcuate nucleus in which preproenkephalin-A mRNA expression is undetectable by in situ hybridization in the absence of circulating estrogen.
- Published
- 1995
13. Temporal regulation by estrogen of β-preprotachykinin mRNA expression in the rat ventromedial nucleus of the hypothalamus
- Author
-
Paul E. Micevych, Krista L. Vink, and Catherine A. Priest
- Subjects
medicine.medical_specialty ,medicine.drug_class ,Hypothalamus ,Gene Expression ,Neuropeptide ,Substance P ,Biology ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Tachykinins ,Internal medicine ,medicine ,Animals ,RNA, Messenger ,Protein Precursors ,Molecular Biology ,In Situ Hybridization ,Estradiol ,Estrogens ,Lordosis behavior ,Rats ,medicine.anatomical_structure ,Endocrinology ,Ventromedial nucleus of the hypothalamus ,chemistry ,Estrogen ,Female ,Nucleus ,Estrogen receptor alpha ,hormones, hormone substitutes, and hormone antagonists - Abstract
In the rat, reproduction and sexual behavior are controlled by the gonadal steroid regulation of synaptic interactions within the sexually dimorphic limbic-hypothalamic system. The effects of estrogen on the ventromedial nucleus of the hypothalamus, one nucleus within the circuit, are central to the modulation of this behavior. Involvement of the neuropeptide substance P, a member of the tachykinin family of neuropeptides, has been implicated in the regulation of both lordosis behavior and gonadotropin release. However, previous studies have provided conflicting evidence as to whether levels of substance P in the ventromedial nucleus of the hypothalamus are modulated by circulating estrogens. To study this question further, in situ hybridization histochemistry was used to examine levels of beta-preprotachykinin mRNA, which encodes substance P and other tachykinins, in the ventrolateral subdivision of the ventromedial hypothalamus at 10 consecutive timepoints over a 4 day period subsequent to an acute administration of estrogen. Following estrogen treatment, beta-preprotachykinin mRNA expression was increased in cells of the ventrolateral portion of the ventromedial nucleus of the hypothalamus which constitutively express beta-preprotachykinin mRNA; however, there were no statistically significant changes in the number of cells that express detectable levels of beta-preprotachykinin mRNA in the ventrolateral portion of the ventromedial nucleus. Estrogen treatment produced two peaks of beta-preprotachykinin mRNA expression, the first at 2 h and the second at 48 h after the injection of estrogen. These data indicate that estrogen has both rapid and prolonged effects on beta-preprotachykinin mRNA levels, suggesting that estrogen may affect different cellular mechanisms relevant to the induction of beta-preprotachykinin mRNA expression.
- Published
- 1995
14. Synthetic peptide-acrylate surfaces for long-term self-renewal and cardiomyocyte differentiation of human embryonic stem cells
- Author
-
Jodelle Karen Nelson, Liqun Qiu, Christopher B. Shogbon, Zara Melkoumian, Andrei Gennadyevich Fadeev, James P. Beltzer, Ralph Brandenberger, Yue Zhou, Jennifer L. Weber, Arthur W. Martin, Santona Pal, Jiwei Yang, Peter West, Catherine A. Priest, Paula Dolley-Sonneville, and David M. Weber
- Subjects
Time Factors ,Somatic cell ,Surface Properties ,Cellular differentiation ,Cell ,Molecular Sequence Data ,Biomedical Engineering ,Cell Culture Techniques ,Bioengineering ,Biology ,Cell morphology ,Applied Microbiology and Biotechnology ,Mice ,medicine ,Animals ,Humans ,Myocytes, Cardiac ,Amino Acid Sequence ,Embryonic Stem Cells ,Cell Proliferation ,Matrigel ,Cell Differentiation ,Anatomy ,Embryonic stem cell ,Cell biology ,medicine.anatomical_structure ,Acrylates ,Cell culture ,Molecular Medicine ,Stem cell ,Peptides ,Biotechnology - Abstract
Human embryonic stem cells (hESCs) have two properties of interest for the development of cell therapies: self-renewal and the potential to differentiate into all major lineages of somatic cells in the human body. Widespread clinical application of hESC-derived cells will require culture methods that are low-cost, robust, scalable and use chemically defined raw materials. Here we describe synthetic peptide-acrylate surfaces (PAS) that support self-renewal of hESCs in chemically defined, xeno-free medium. H1 and H7 hESCs were successfully maintained on PAS for over ten passages. Cell morphology and phenotypic marker expression were similar for cells cultured on PAS or Matrigel. Cells on PAS retained normal karyotype and pluripotency and were able to differentiate to functional cardiomyocytes on PAS. Finally, PAS were scaled up to large culture-vessel formats. Synthetic, xeno-free, scalable surfaces that support the self-renewal and differentiation of hESCs will be useful for both research purposes and development of cell therapies.
- Published
- 2009
15. Actions of Sex Steroids on Behaviours Beyond Reproductive Reflexes
- Author
-
Donald W. Pfaff and Catherine A. Priest
- Subjects
Regulation of gene expression ,medicine.medical_specialty ,Mechanism (biology) ,Long-term potentiation ,Biology ,Endocrinology ,Mood ,Hypothalamus ,Internal medicine ,Neuroplasticity ,medicine ,Premovement neuronal activity ,Opioid peptide ,Neuroscience - Abstract
The actions of sex steroids in the brain have been shown, from molecular to systems levels, to control reproductive behaviour in a wide range of vertebrates. It has become increasingly clear that gonadal steroid hormones have regulatory functions which extend far beyond the direct coordination of an animal's physiological state and its display of sexual behaviour. While some of these actions may include changes in mood or other behavioural measures, such as exploration or excitability, sex steroid hormones also influence neural plasticity, neuronal activity and, possibly, learning and memory, as reflected by long-term potentiation or age-related deficits. Here we describe two systems that have been used to explore the non-reproductive roles of gonadal steroid hormones. The first of these is to examine the oestrogen-sensitive opioid peptide gene expression in the hypothalamus. Currently, we are attempting to identify the types of behaviour which may be altered consequent to the oestrogenic induction of the preproenkephalin gene. The second approach involves studying the effects of progesterone at the neuronal cell membrane and characterizing the metabolites of progesterone which have benzodiazepine-like actions in the brain. A number of studies suggest that this may provide an alternative mechanism through which progesterone can influence mood or behaviour.
- Published
- 2007
16. Immunological properties of human embryonic stem cell-derived oligodendrocyte progenitor cells
- Author
-
Anish Sen Majumdar, Ross M. Okamura, Jane S. Lebkowski, Jerrod Denham, Catherine A. Priest, and Melinda Au
- Subjects
medicine.medical_treatment ,Cellular differentiation ,T-Lymphocytes ,Immunology ,Enzyme-Linked Immunosorbent Assay ,Mice, SCID ,Mice ,Immune system ,Fetus ,medicine ,Immunology and Allergy ,Animals ,Humans ,Cells, Cultured ,Embryonic Stem Cells ,Mice, Knockout ,biology ,Cell Differentiation ,Flow Cytometry ,Embryonic stem cell ,Cell biology ,Endothelial stem cell ,DNA-Binding Proteins ,stomatognathic diseases ,Oligodendroglia ,Neurology ,Spinal Cord ,embryonic structures ,biology.protein ,Sialic Acids ,Cytokines ,Neurology (clinical) ,Stem cell ,Antibody ,Adult stem cell ,Allotransplantation ,Stem Cell Transplantation - Abstract
A major concern in the use of allotransplantation of human embryonic stem cell (hESC)-based therapies is the possibility of allogeneic rejection by the host's immune system. In this report, we determined the immunological properties of hESC-derived oligodendrocyte progenitor cells (OPC) that have the potential for clinical application for the treatment of patients with spinal cord injury. In vitro immunological studies suggest that hESC-derived OPCs are poor targets for both the innate and the adaptive human immune effector cells as well as resistant to lysis by anti-Neu5Gc antibodies. These results indicate that hESC-derived OPCs retain some of the unique immunological properties of the parental cell line from which they were differentiated.
- Published
- 2007
17. Anorectic estrogen mimics leptin's effect on the rewiring of melanocortin cells and Stat3 signaling in obese animals
- Author
-
Sabrina Diano, Yongzhan Nie, Gerald I. Shulman, Charles V. Mobbs, Cheol Soo Choi, Tamas L. Horvath, Yan Rao, Xiao-Bing Gao, Catherine A. Priest, Dominique Toran-Allerand, Qian Gao, Csaba Leranth, James L. Roberts, Ingo Bechmann, and Gábor Mezei
- Subjects
Leptin ,Male ,STAT3 Transcription Factor ,medicine.medical_specialty ,Pro-Opiomelanocortin ,media_common.quotation_subject ,Ovariectomy ,Mice, Obese ,General Biochemistry, Genetics and Molecular Biology ,Rats, Sprague-Dawley ,Mice ,Arcuate nucleus ,Internal medicine ,Medicine ,Animals ,Obesity ,media_common ,Injections, Intraventricular ,Mice, Knockout ,Neurons ,Leptin receptor ,Estradiol ,business.industry ,digestive, oral, and skin physiology ,Body Weight ,Arcuate Nucleus of Hypothalamus ,Estrogen Receptor alpha ,Excitatory Postsynaptic Potentials ,Appetite ,General Medicine ,Anorexia ,Melanocortins ,Rats ,Mice, Inbred C57BL ,Microscopy, Electron ,Endocrinology ,Synaptic plasticity ,Anorectic ,Female ,Melanocortin ,business ,hormones, hormone substitutes, and hormone antagonists ,Hormone ,Signal Transduction - Abstract
Metabolic hormones, such as leptin, alter the input organization of hypothalamic circuits, resulting in increased pro-opiomelanocortin (POMC) tone, followed by decreased food intake and adiposity. The gonadal steroid estradiol can also reduce appetite and adiposity, and it influences synaptic plasticity. Here we report that estradiol (E2) triggers a robust increase in the number of excitatory inputs to POMC neurons in the arcuate nucleus of wild-type rats and mice. This rearrangement of synapses in the arcuate nucleus is leptin independent because it also occurred in leptin-deficient (ob/ob) and leptin receptor-deficient (db/db) mice, and was paralleled by decreased food intake and body weight gain as well as increased energy expenditure. However, estrogen-induced decrease in body weight was dependent on Stat3 activation in the brain. These observations support the notion that synaptic plasticity of arcuate nucleus feeding circuits is an inherent element in body weight regulation and offer alternative approaches to reducing adiposity under conditions of failed leptin receptor signaling.
- Published
- 2006
18. Gap junction proteins in inhibitory neurons of the adult barrel neocortex
- Author
-
Catherine A. Priest, Alison J. Thompson, and Asaf Keller
- Subjects
Male ,Neurofilament ,Physiology ,Connexin ,Fluorescent Antibody Technique ,Neocortex ,Connexins ,Mice ,Cortex (anatomy) ,medicine ,Animals ,Tissue Distribution ,education ,Neurons ,education.field_of_study ,Microscopy, Confocal ,biology ,Gap junction ,Somatosensory Cortex ,Immunohistochemistry ,Sensory Systems ,medicine.anatomical_structure ,Parvalbumins ,nervous system ,biology.protein ,Connexin 32 ,sense organs ,NeuN ,Neuroscience ,Parvalbumin ,Biomarkers - Abstract
Recent studies indicate that electrical coupling among cortical neurons may persist throughout development; electrophysiological recordings made in cortical slices from young rats reveal that numerous GABAergic neurons are electrically coupled. To determine whether these in vitro findings reflect an inhibitory neural circuit that could be functionally relevant in vivo in adult rodents, we sought to identify whether inhibitory, parvalbumin-containing neurons of the mature cortex express gap junction proteins. Immunohistochemistry was used to examine the laminar distribution of the gap junction-forming proteins connexin 32 (Cx32), connexin 36 (Cx36) and connexin 43 (Cx43) in the somatosensory cortex of the adult mouse. Double labeling immunofluorescence identified Cx32, Cx36 and Cx43 in cortical neurons that were immunoreactive (-ir) for the neuronal markers neurofilament 145 kDa and neuronal nuclei (NeuN). Parvalbumin-ir neurons throughout the cortical laminae were labeled with Cx32-ir, Cx36-ir and Cx43-ir. Stereological methods were used to quantify the extent of parvalbumin colocalization with connexins. Analysis indicated that approximately 40% of parvalbumin-ir neurons were double labeled with either Cx32-ir or Cx43-ir, and approximately 50% of parvalbumin-ir neurons were double labeled with Cx36. These findings establish an anatomical substrate for widespread electrical coupling of neurons in somatosensory cortex and suggest that gap junctions among inhibitory interneurons may persist into adulthood, providing an important mechanism for neuronal communication.
- Published
- 2002
19. Functional Circuitry Involved in the Regulation of Whisker Movements
- Author
-
Catherine A. Priest, Alexis M. Hattox, and Asaf Keller
- Subjects
Male ,Cholera Toxin ,Movement ,Pyramidal Tracts ,Biotin ,Biology ,Reticular formation ,Article ,Metencephalon ,Rats, Sprague-Dawley ,Mesencephalon ,medicine ,Tegmentum ,Animals ,Fluorescent Dyes ,Nucleus ambiguus ,Motor Neurons ,Biotinylated dextran amine ,Medulla Oblongata ,General Neuroscience ,Superior colliculus ,Reticular Formation ,Motor Cortex ,Dextrans ,Paramedian pontine reticular formation ,Anatomy ,Immunohistochemistry ,Pons ,Electric Stimulation ,Rats ,Facial Nerve ,medicine.anatomical_structure ,nervous system ,Vibrissae ,Brainstem ,Neuroscience ,Brain Stem - Abstract
Neuroanatomical tract-tracing methods were used to identify the oligosynaptic circuitry by which the whisker representation of the motor cortex (wMCx) influences the facial motoneurons that control whisking activity (wFMNs). Injections of the retrograde tracer cholera toxin subunit B into physiologically identified wFMNs in the lateral facial nucleus resulted in dense, bilateral labeling throughout the brainstem reticular formation and in the ambiguus nucleus as well as predominantly ipsilateral labeling in the paralemniscal, pedunculopontine tegmental, Kolliker-Fuse, and parabrachial nuclei. In addition, neurons in the following midbrain regions projected to the wFMNs: superior colliculus, red nucleus, periaqueductal gray, mesencephalon, pons, and several nuclei involved in oculomotor behaviors. Injections of the anterograde tracer biotinylated dextran amine into the wMCx revealed direct projections to the brainstem reticular formation as well as multiple brainstem and midbrain structures shown to project to the wFMNs. Regions in which retrograde labeling and anterograde labeling overlap most extensively include the brainstem parvocellular, gigantocellular, intermediate, and medullary (dorsal and ventral) reticular formations; ambiguus nucleus; and midbrain superior colliculus and deep mesencephalic nucleus. Other regions that contain less dense regions of combined anterograde and retrograde labeling include the following nuclei: the interstitial nucleus of medial longitudinal fasciculus, the pontine reticular formation, and the lateral periaqueductal gray. Premotoneurons that receive dense inputs from the wMCx are likely to be important mediators of cortical regulation of whisker movements and may be a key component in a central pattern generator involved in the generation of rhythmic whisking activity.
- Published
- 2002
20. Corning® Synthemax™ Surface: a tool for feeder-free, xeno-free culture of human embryonic stem cells
- Author
-
Yue Zhou, Zara Melkoumian, Ralph Brandenberger, Andrei Gennadyevich Fadeev, Jennifer L. Weber, Jiwei Yang, David M. Weber, Paula Dolley-Sonneville, and Catherine A. Priest
- Subjects
Chemistry ,embryonic structures ,Feeder free ,Cell Biology ,Molecular Biology ,Biochemistry ,Embryonic stem cell ,Xeno free ,Biotechnology ,Cell biology - Abstract
Currently, human embryonic stem cells (hESCs) are cultured on feeder cells or complex mixtures of proteins extracted from mouse tumors1,2. To allow commercialization of hESC-derived therapeutic cells, culture methods are required that are robust and scalable and that use chemically defined, xeno-free materials. Corning Synthemax Surface is a novel synthetic surface that permits consistent long-term self-renewal of multiple hESC lines in defined, xeno-free media and differentiation of cells to functional cardiomyocytes3.
- Published
- 2010
21. Estrogen and tamoxifen differentially regulate beta-endorphin and cFos expression and neuronal colocalization in the arcuate nucleus of the rat
- Author
-
Catherine A. Priest and James L. Roberts
- Subjects
medicine.medical_specialty ,Pro-Opiomelanocortin ,medicine.drug_class ,Endocrinology, Diabetes and Metabolism ,Biology ,Rats, Sprague-Dawley ,Cellular and Molecular Neuroscience ,Endocrinology ,Internal medicine ,medicine ,Animals ,RNA, Messenger ,Opioid peptide ,Estrogen receptor beta ,Endogenous opioid ,Hormone response element ,Neurons ,Estradiol ,Endocrine and Autonomic Systems ,beta-Endorphin ,Arcuate Nucleus of Hypothalamus ,Colocalization ,Genes, fos ,Estrogens ,Immunohistochemistry ,Rats ,Tamoxifen ,Gene Expression Regulation ,Estrogen ,Female ,Estrogen receptor alpha ,Proto-Oncogene Proteins c-fos ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Estrogen regulates hypothalamic gene expression, synthesis and release of the endogenous opioid peptide β-endorphin (βEND), although a consensus estrogen response element sequence has not been identified in the rat proopiomelanocortin (POMC) gene. POMC gene expression is also regulated by the activation of AP-1 promoter elements, which are known to be estrogen sensitive. The present studies examine whether estrogen modulates the hypothalamic POMC system through a non-classical mechanism involving AP-1 binding proteins such as cFos. Immunohistochemical double-labeling for βEND and cFos was used and immunoreactive (-ir) populations were quantified in the arcuate nucleus and periarcuate area across time using unbiased stereological methods. Ovariectomized rats were injected with 50 µg estradiol (E2), 500 µg tamoxifen citrate (TAM) or both (E2+TAM) and were perfused 1, 2, 4 or 48 h later. E2 rapidly increased numbers of cFos-ir, βEND-ir and doubly-labeled cells after 4 h, and the number of βEND-ir cells remained high 48 h later, suggesting that the stimulatory effects of cFos on POMC in the hypothalamus persist after the cFos signal decays. Treatment with TAM alone did not affect the numbers of immunoreactive cells, although E2+TAM blocked the E2-mediated induction in all immunoreactive populations. Similar effects were seen at the transcriptional level. E2 increased hypothalamic POMC mRNA after 4 h, while TAM treatment or coadministration of E2+TAM did not significantly change the levels of POMC mRNA. Cellular colocalization of βEND-ir and cFos-ir supports a possible intracellular co-regulation of these peptides by an estrogen-dependent mechanism within a subset of hypothalamic neurons. It does not, however, appear that E2 acts directly through an AP-1 site within the POMC gene.
- Published
- 2000
22. Tonic and synaptically evoked presynaptic inhibition of sensory input to the rat olfactory bulb via GABA(B) heteroreceptors
- Author
-
Vassiliki Aroniadou-Anderjaska, Matthew Ennis, Catherine A. Priest, Michael T. Shipley, and Fu-Ming Zhou
- Subjects
Baclofen ,Olfactory Nerve ,Physiology ,Presynaptic inhibition ,Presynaptic Terminals ,Biology ,In Vitro Techniques ,Receptors, N-Methyl-D-Aspartate ,Synaptic Transmission ,Tonic (physiology) ,GABA Antagonists ,Glutamatergic ,Organophosphorus Compounds ,Olfactory nerve ,Interneurons ,medicine ,Reaction Time ,Animals ,Receptors, AMPA ,Axon ,Rats, Wistar ,GABA Agonists ,gamma-Aminobutyric Acid ,Olfactory receptor ,General Neuroscience ,Excitatory Postsynaptic Potentials ,Neural Inhibition ,Olfactory Pathways ,Olfactory Bulb ,Olfactory bulb ,Rats ,Sensory input ,medicine.anatomical_structure ,nervous system ,Receptors, GABA-B ,GABA-B Receptor Agonists ,Neuroscience ,GABA-B Receptor Antagonists - Abstract
Olfactory receptor neurons of the nasal epithelium send their axons, via the olfactory nerve (ON), to the glomeruli of the olfactory bulb (OB), where the axon terminals form glutamatergic synapses with the apical dendrites of mitral and tufted cells, the output cells of the OB, and with juxtaglomerular (JG) interneurons. Many JG cells are GABAergic. Here we show that, despite the absence of conventional synapses, GABA released from JG cells activates GABABreceptors on ON terminals and inhibits glutamate release both tonically and in response to ON stimulation. Field potential recordings and current-source density analysis, as well as intracellular and whole cell recording techniques were used in rat OB slices. Baclofen (2–5 μM), a GABABagonist, completely suppressed ON-evoked synaptic responses of both mitral/tufted cells and JG cells, with no evidence for postsynaptic effects. Baclofen (0.5–1 μM) also reversed paired-pulse depression (PPD) of mitral/tufted cell responses to paired-pulse facilitation (PPF), and reduced depression of JG cell excitatory postsynaptic currents (EPSCs) during repetitive ON stimulation. These results suggest that baclofen reduced the probability of glutamate release from ON terminals. The GABABantagonists CGP35348 or CGP55845A increased mitral/tufted cell responses evoked by single-pulse ON stimulation, suggesting that glutamate release from ON terminals is tonically suppressed via GABABreceptors. The same antagonists reduced PPD of ON-evoked mitral/tufted cell responses at interstimulus intervals 50–400 ms. This finding suggests that a single ON impulse evokes sufficient GABA release, presumably from JG cells, to activate GABABreceptors on ON terminals. Thus GABABheteroreceptors on ON terminals are activated by ambient levels of extrasynaptic GABA, and by ON input to the OB. The time course of ON-evoked, GABABpresynaptic inhibition suggests that neurotransmission to M/T cells and JG cells will be significantly suppressed when ON impulses arrive in glomeruli at 2.5–20 Hz. GABABreceptor–mediated presynaptic inhibition of sensory input to the OB may play an important role in shaping the activation pattern of the OB glomeruli during olfactory coding.
- Published
- 2000
23. Regulation of cholecystokinin receptors in the ventromedial nucleus of the hypothalamus: sex steroid hormone effects
- Author
-
Paul E. Micevych, Catherine A. Priest, and Paul Popper
- Subjects
Testosterone propionate ,Male ,medicine.medical_specialty ,medicine.drug_class ,Ovariectomy ,Down-Regulation ,digestive system ,Cholecystokinin receptor ,Iodine Radioisotopes ,chemistry.chemical_compound ,Internal medicine ,medicine ,Animals ,Testosterone ,Gonadal Steroid Hormones ,Molecular Biology ,Sex Characteristics ,Estradiol ,Chemistry ,General Neuroscience ,digestive, oral, and skin physiology ,Androgen ,Rats ,Ventromedial nucleus of the hypothalamus ,Endocrinology ,Hypothalamus ,Sex steroid ,Estrogen ,Ventromedial Hypothalamic Nucleus ,Autoradiography ,Female ,Receptors, Cholecystokinin ,Neurology (clinical) ,Orchiectomy ,hormones, hormone substitutes, and hormone antagonists ,Developmental Biology - Abstract
Quantitative autoradiography was used to analyze cholecystokinin receptor (CCK-R) binding in the ventromedial hypothalamic nucleus (VMH) of gonadectomized rats treated with estrogen or testosterone. In the rostral VMH, sex steroids did not affect binding levels. In the caudal VMH, in both gonadectomized male and female rats, the levels of CCK-R binding were decreased 24 h after injection of 50 micrograms of estrogen benzoate but were not changed after injection of 300 micrograms of testosterone propionate. We hypothesize that these changes in CCK-R binding in the VMH reflect ligand-induced down-regulation that result from an estrogen-facilitation of stimulated CCK release in the VMH.
- Published
- 1996
24. 232. Transplantation of Human Embryonic Stem Cell Derived Oligodendroglial Progenitors for the Treatment of Spinal Cord Injury
- Author
-
Hans S. Keirstead, Catherine A. Priest, Jane S. Lebkowski, Giovanna M. Bernal, Jerrod Denham, Scott Thies, Minodora O. Totoiu, and Gabriel Nistor
- Subjects
Pharmacology ,Cellular differentiation ,Cell ,Biology ,Embryonic stem cell ,Cell biology ,Transplantation ,Haematopoiesis ,medicine.anatomical_structure ,Drug Discovery ,Immunology ,Genetics ,medicine ,Molecular Medicine ,Stem cell ,Progenitor cell ,Molecular Biology ,Adult stem cell - Abstract
Human embryonic stem cells (hESCs) can replicate indefinitely in culture yet upon appropriate cues differentiate into elements of all three embryonic germ layers. Because of these proliferative and differentiative capabilities, hESCs could serve as as the source material for transplantable cells for tissue restorative therapies. To this end, we have developed protocols to direct the differentiation of hESCs into candidate target cell populations for therapeutic activity. Using combinations of extracellular matrix factors, growth factors, and select media components, we have produced cardiomyocytes, neural progenitors, neurons, oligodendroglial progenitors, hematopoietic cells, osteoblasts, and hepatocytes from hES cells. In all cases, the differentiated cells display both a panel of markers and appropriate function characteristic of the target cell. For all of these differentiated cell populations, a thorough cell compositional analysis has been completed or is underway.
- Published
- 2004
25. Effects of sex steroids on the cholecystokinin circuit modulating reproductive behavior
- Author
-
Catherine A. Priest, Paul Popper, and Paul E. Micevych
- Subjects
medicine.medical_specialty ,Sex Steroid Hormones ,Biology ,Cholecystokinin receptor ,Prolactin ,Gonadotropin secretion ,Endocrinology ,Somatostatin ,Internal medicine ,medicine ,biology.protein ,Aromatase ,Testosterone ,Cholecystokinin - Published
- 1995
26. Microinjection of cholecystokinin into the medial preoptic nucleus facilitates lordosis behavior in the female rat
- Author
-
Catherine A. Priest, Paul E. Micevych, George J. Bloch, and Wayne A. Dornan
- Subjects
medicine.medical_specialty ,Microinjections ,Lordosis ,Ovariectomy ,Posture ,Neuropeptide ,Experimental and Cognitive Psychology ,Biology ,Nucleus accumbens ,Nucleus Accumbens ,Sexual Behavior, Animal ,Behavioral Neuroscience ,Internal medicine ,medicine ,Animals ,Microinjection ,Injections, Intraventricular ,Cholecystokinin ,Dose-Response Relationship, Drug ,Estradiol ,Immunization, Passive ,food and beverages ,Lordosis behavior ,medicine.disease ,Preoptic Area ,Rats ,Endocrinology ,Hypothalamus ,Ovariectomized rat ,Female ,Septal Nuclei ,hormones, hormone substitutes, and hormone antagonists - Abstract
We examined the effect of cholecystokinin (CCK) on lordosis behavior when administered into the medial preoptic area or the nucleus accumbens (NAcc) of ovariectomized estrogen-primed female rats. The frequency of lordotic responses was measured subsequent to unilateral microinjections of sulphated octapeptide CCK (sCCK-8) into the medial preoptic nucleus (MPN) or the NAcc. In the first experiment, three doses of sCCK-8 (1, 5, and 50 ng) microinjected into the MPN, and 50 ng injected into the NAcc produced a marked facilitation of lordosis. In a separate experiment, unilateral injections of an undiluted sCCK-8 antiserum into the MPN produced significant reduction in lordosis behavior in highly receptive females when compared with a normal rabbit serum injected control group. The results of the present study indicate that the CCK innervation of the MPN is involved in the neural regulation of lordosis behavior in the female rat.
- Published
- 1989
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.