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排序方式: 共有397条查询结果,搜索用时 15 毫秒
101.
Recombination signatures distinguish embryonic stem cells derived by parthenogenesis and somatic cell nuclear transfer 总被引:3,自引:0,他引:3
Kim K Ng K Rugg-Gunn PJ Shieh JH Kirak O Jaenisch R Wakayama T Moore MA Pedersen RA Daley GQ 《Cell Stem Cell》2007,1(3):346-352
Parthenogenesis and somatic cell nuclear transfer (SCNT) are two methods for deriving embryonic stem (ES) cells that are genetically matched to the oocyte donor or somatic cell donor, respectively. Using genome-wide single nucleotide polymorphism (SNP) analysis, we demonstrate distinct signatures of genetic recombination that distinguish parthenogenetic ES cells from those generated by SCNT. We applied SNP analysis to the human ES cell line SCNT-hES-1, previously claimed to have been derived by SCNT, and present evidence that it represents a human parthenogenetic ES cell line. Genome-wide SNP analysis represents a means to validate the genetic provenance of an ES cell line. 相似文献
102.
Andrew J Scotter Meng Guo Melanie M Tomczak Margaret E Daley Robert L Campbell Richard J Oko David A Bateman Avijit Chakrabartty Brian D Sykes Peter L Davies 《BMC structural biology》2007,7(1):63
Background
A right-handed, calcium-dependent β-roll structure found in secreted proteases and repeat-in-toxin proteins was used as a template for the design of minimal, soluble, monomeric polypeptides that would fold in the presence of Ca2+. Two polypeptides were synthesised to contain two and four metal-binding sites, respectively, and exploit stacked tryptophan pairs to stabilise the fold and report on the conformational state of the polypeptide. 相似文献103.
The recent United States measles epidemic has sparked another contentious national discussion about childhood vaccination. A growing number of parents are expressing concerns about the safety of vaccines, often fueled by misinformation from the internet, books, and other nonmedical sources. Many of these concerned parents are choosing to refuse or delay childhood vaccines, placing their children and surrounding communities at risk for serious diseases that are nearly 100% preventable with vaccination. Between 10% and 15% of parents are asking physicians to space out the timing of vaccines, which often poses an ethical dilemma for physicians. This trend reflects a tension between personal liberty and public health, as parents fight to control the decisions that affect the health of their children and public health officials strive to maintain high immunization rates to prevent outbreaks of vaccine-preventable diseases. Interventions to address this emerging public health issue are needed. We describe a framework by which web-based interventions can be used to help parents make evidence-based decisions about childhood vaccinations.
About the Author
Jason Glanz, PhD, is an epidemiologist and senior research investigator at Kaiser Permanente Colorado, Institute for Health Research. He is also an assistant professor in the Department of Epidemiology, Colorado School of Public Health. Dr. Glanz’s research focuses on vaccine safety and vaccine hesitancy. Dr. Glanz is currently a principal investigator with the Vaccine Safety Datalink, a national Centers for Disease Control and Prevention (CDC)-funded project that examines the safety of vaccines. Dr. Glanz also leads research efforts to develop risk communication strategies to help reduce parental vaccination concerns. 相似文献104.
To visualize the latter stages of cell division in live Escherichia coli, we have carried out fluorescence recovery after photobleaching (FRAP) on 121 cells expressing cytoplasmic green fluorescent protein and periplasmic mCherry. Our data show conclusively that the cytoplasm is sealed prior to the periplasm during the division event. 相似文献
105.
M R Darling L Jackson-Boeters T D Daley E P Diamandis 《The journal of histochemistry and cytochemistry》2006,54(3):337-342
Human kallikrein 6 (hK6), also known as zyme/protease M/neurosin), is expressed in many normal glandular tissues. The aim of this study was to determine whether hK6 is expressed in salivary gland tissues and salivary gland tumors (both benign and malignant), using an immunohistochemical method. Pleomorphic adenomas (PA), adenoid cystic carcinomas, polymorphous low-grade adenocarcinomas, acinic cell carcinomas, mucoepidermoid carcinomas, and adenocarcinomas not otherwise specified of both minor and major salivary glands were examined. Cells lining duct-like structures and non-duct-like cells were scored. Only in PA of minor salivary gland origin was overall staining higher in duct-like than in non-duct-like cells. In all other tumors exhibiting both types of cells, hK6 staining was similar in both duct-like and non-duct-like cells. Tumors that exhibited non-duct-like cells only also exhibited cytoplasmic staining. Results of this study show that salivary gland tumors express hK6, apparently downregulated in comparison with normal salivary gland tissue, and that this expression is not specific for any of the tumors studied. 相似文献
106.
Darling MR Jackson-Boeters L Daley TD Diamandis EP 《The International journal of biological markers》2006,21(2):106-110
The human kallikrein 13 protein (hK13) is expressed in many normal tissues. Petraki et al have previously described presence of hK13 in salivary gland tissue, localized to duct epithelia and some acinar cells. The aim of this study was to determine whether hK13 is expressed in salivary gland tissues and salivary gland tumors (both benign and malignant), in order to compare normal with tumor tissues. Pleomorphic adenomas (PA), adenoid cystic carcinomas (ACC), polymorphous low grade adenocarcinomas (PLGA), acinic cell carcinomas (ACI), mucoepidermoid carcinomas (MEC) and adenocarcinomas not otherwise specified (ANOS) of both minor and major salivary glands were examined. The results of this study indicate that most salivary gland tumors show high levels of expression of hK13. Overall, staining in PA was significantly less than that seen in normal salivary gland tissue. PLGA, ACC and ANOS each stained significantly more than normal salivary gland tissue while MEC and ACI did not. Ductal cells and cells lining duct-like structures showed a higher intensity of staining than non-ductal cells in most tumors. Tumors which exhibited only non-ductal cells also exhibited cytoplasmic staining. In conclusion, we demonstrate the high expression of hK13 in several common salivary gland tumors. 相似文献
107.
Denise Daley Mathieu Lemire Loubna Akhabir Moira Chan-Yeung Jian Qing He Treena McDonald Andrew Sandford Dorota Stefanowicz Ben Tripp David Zamar Yohan Bosse Vincent Ferretti Alexandre Montpetit Marie-Catherine Tessier Allan Becker Anita L. Kozyrskyj John Beilby Pamela A. McCaskie Bill Musk Nicole Warrington Alan James Catherine Laprise Lyle J. Palmer Peter D. Paré Thomas J. Hudson 《Human genetics》2009,125(4):445-459
108.
109.
Highly efficient reprogramming to pluripotency and directed differentiation of human cells with synthetic modified mRNA 总被引:6,自引:0,他引:6
Warren L Manos PD Ahfeldt T Loh YH Li H Lau F Ebina W Mandal PK Smith ZD Meissner A Daley GQ Brack AS Collins JJ Cowan C Schlaeger TM Rossi DJ 《Cell Stem Cell》2010,7(5):618-630
Clinical application of induced pluripotent stem cells (iPSCs) is limited by the low efficiency of iPSC derivation and the fact that most protocols modify the genome to effect cellular reprogramming. Moreover, safe and effective means of directing the fate of patient-specific iPSCs toward clinically useful cell types are lacking. Here we describe a simple, nonintegrating strategy for reprogramming cell fate based on administration of synthetic mRNA modified to overcome innate antiviral responses. We show that this approach can reprogram multiple human cell types to pluripotency with efficiencies that greatly surpass established protocols. We further show that the same technology can be used to efficiently direct the differentiation of RNA-induced pluripotent stem cells (RiPSCs) into terminally differentiated myogenic cells. This technology represents a safe, efficient strategy for somatic cell reprogramming and directing cell fate that has broad applicability for basic research, disease modeling, and regenerative medicine. 相似文献
110.
The demonstration of germ cell and haploid gamete development from embryonic stem cells (ESCs) in vitro has engendered a unique set of possibilities for the study of germ cell development and the associated epigenetic phenomenon. The process of embryoid body (EB) differentiation, like teratoma formation, signifies a spontaneous differentiation of ESCs into cells of all three germ layers, and it is from these differentiating aggregates of cells that putative primordial germ cells (PGCs) and more mature gametes can be identified and isolated. The differentiation system presented here requires the differentiation of murine ESCs into EBs and the subsequent isolation of PGCs as well as haploid male gametes from EBs at various stages of differentiation. It serves as a platform for studying the poorly understood process of germ cell allocation, imprint erasure and gamete formation, with 4-6 weeks being required to isolate PGCs as well as haploid cells. 相似文献