Publications by authors named "Sherley J"

Article Synopsis
  • Developing advanced cell therapy products involves defining key concepts like mechanism of action (MOA), potency, and efficacy, which can be challenging but is crucial for success.
  • The text introduces a logical framework that aligns with regulatory guidelines and draws on insights from 27 FDA-approved cell therapy products to better understand these concepts.
  • It highlights the complexity of correlating potency test results with clinical outcomes, discusses common misconceptions, and emphasizes the need for effective communication among developers throughout the product development process.
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Article Synopsis
  • - Kinetic stem cell (KSC) counting is a new technology for accurately measuring tissue stem cells in various organ and tissue samples, addressing a significant gap in stem cell research.
  • - The study tested KSC counting on human oral alveolar bone cell preparations, showing high precision in determining the fractions of mesenchymal stem cells (MSCs) across multiple independent sites.
  • - The results also demonstrated KSC counting's capability to identify factors affecting different stem cell subtypes, supporting its potential to enhance advancements in stem cell science and related medical fields.
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A continuing limitation and major challenge in the development and utilization of predictable stem cell therapies (SCTs) is the determination of the optimal dosages of stem cells. Herein, we report the quantification of stem cell fractions (SCF) of human mesenchymal stem cell (MSC) preparations derived from oral tissues. A novel computational methodology, kinetic stem cell (KSC) counting, was used to quantify the SCF and specific cell culture kinetics of stem cells in oral alveolar bone-derived MSC (aBMSCs) from eight patients.

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A recently described kinetic stem cell (KSC) counting method was used to investigate the stem-cell-specific effects of commercial growth factor supplements used for expanding stem cells in adipose-tissue-derived mesenchymal cell preparations. The supplements were a proprietary growth factor product, a source of fetal bovine serum, two sources of pooled human sera, and two sources of human platelet lysate. KSC counting analyses were performed to monitor effects on the fraction and viability of stem cells in serial cultures with their respective supplements.

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Since the U.S. Supreme Court issued its landmark decision in 1973 to legalize abortion, over 60 million preborn have been killed by elective abortion.

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Background: Neonatal tetanus (NT) is a deadly nervous system disorder that is endemic to Afghanistan. Administering sufficient doses of tetanus toxoid containing vaccine (TTCV) during pregnancy can pass antibodies to the fetus and therefore prevent NT. Using survey data, we investigated the association between area of residence (urban or rural) and sufficient antenatal TTCV coverage among women aged 15-49 years in Afghanistan during their most recent pregnancy in the past 5 years that resulted in a live birth.

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Black women have been experiencing induced abortions at a rate nearly 4 times that of White women for at least 3 decades, and likely much longer. The impact in years of potential life lost, given abortion's high incidence and racially skewed distribution, indicates that it is the most demographically consequential occurrence for the minority population. The science community has refused to engage on the subject and the popular media has essentially ignored it.

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There is a long-standing unmet clinical need for biomarkers with high specificity for distributed stem cells (DSCs) in tissues, or for use in diagnostic and therapeutic cell preparations (e.g., bone marrow).

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The role of immortal DNA strands that co-segregate during mitosis of asymmetrically self-renewing distributed stem cells (DSCs) is unknown. Previously, investigation of immortal DNA strand function and molecular mechanisms responsible for their nonrandom co-segregation was precluded by difficulty in identifying DSCs and immortal DNA strands. Here, we report the use of two technological innovations, selective DSC expansion and establishment of H2A.

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Transplantation therapy for type I diabetes (T1D) might be improved if pancreatic stem cells were readily available for investigation. Unlike macroscopic islets, pancreatic tissue stem cells could more easily access the retroperitoneal pancreatic environment and thereby might achieve more effective pancreatic regeneration. Unfortunately, whether the adult pancreas actually contains renewing stem cells continues as a controversial issue in diabetes research.

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A total of eight cellular alterations associated with human carcinogenesis have been framed as the 'hallmarks of cancer'. This representation overlooks a ninth hallmark of cancer: the requirement for tumor-originating distributed stem cells to shift sufficiently from asymmetric to symmetric self-renewal kinetics for attainment of the high cell production rate necessary to form clinically significant tumors within a human lifespan. Overlooking this ninth hallmark costs opportunities for discovery of more selective molecular targets for development of improved cancer therapeutics and missing cancer stem cell biomarkers of greater specificity.

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Immortal strands are the targeted chromosomal DNA strands of nonrandom sister chromatid segregation, a mitotic chromosome segregation pattern unique to asymmetrically self-renewing distributed stem cells (DSCs). By nonrandom segregation, immortal DNA strands become the oldest DNA strands in asymmetrically self-renewing DSCs. Nonrandom segregation of immortal DNA strands may limit DSC mutagenesis, preserve DSC fate, and contribute to DSC aging.

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We investigated the properties of clonally-expanded mouse hair follicle stem cells (HF-SCs) in culture. The expansion method, suppression of asymmetric cell kinetics (SACK), is non-toxic and reversible, allowing evaluation of the cells' asymmetric production of differentiating progeny cells. A tight association was discovered between non-random sister chromatid segregation, a unique property of distributed stem cells (DSCs), like HF-SCs, and a recently described biomarker, Lgr5.

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Although nonrandom sister chromatid segregation is a singular property of distributed stem cells (DSCs) that are responsible for renewing and repairing mature vertebrate tissues, both its cellular function and its molecular mechanism remain unknown. This situation persists in part because of the lack of facile methods for detecting and quantifying nonrandom segregating cells and for identifying chromosomes with immortal DNA strands, the cellular molecules that signify nonrandom segregation. During nonrandom segregation, at each mitosis, asymmetrically self-renewing DSCs continuously cosegregate to themselves the set of chromosomes that contain immortal DNA strands, which are the oldest DNA strands.

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Specific and universal biomarkers for distributed stem cells (DSCs) have been elusive. A major barrier to discovery of such ideal DSC biomarkers is difficulty in obtaining DSCs in sufficient quantity and purity. To solve this problem, we used cell lines genetically engineered for conditional asymmetric self-renewal, the defining DSC property.

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Background: A fundamental problem in cancer research is identifying the cell type that is capable of sustaining neoplastic growth and its origin from normal tissue cells. Recent investigations of a variety of tumor types have shown that phenotypically identifiable and isolable subfractions of cells possess the tumor-forming ability. In the present paper, using two lineage-related human melanoma cell lines, primary melanoma line IGR39 and its metastatic derivative line IGR37, two main observations are reported.

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Previous efforts to improve the efficiency of cellular reprogramming for the generation of induced pluripotent stem cells (iPSCs) have focused mainly on transcription factors and small molecule combinations. Here, we report the results of our focus instead on the phenotype of the cells targeted for reprogramming. We find that adult mouse pancreatic tissue stem cells derived by the method of suppression of asymmetric cell kinetics (SACK) acquire increased potency simply by culture under conditions for the production and maintenance of pluripotent stem cells.

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The existence of immortal DNA strands (IDSs) in distributed stem cells (DSCs) of adult human tissues was first inferred by Cairns. Cairns deduced the existence of IDSs by connecting two seemingly disparate observations - one his own and the other belonging to Lark. Cairns noted a mathematical discrepancy between predicted human tissue cell mutation rates and human cancer incidence.

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The stable expression of reporter genes in adult stem cells (ASCs) has important applications in stem cell biology. The ability to integrate a noncytotoxic, fluorescent reporter gene into the genome of ASCs with the capability to track ASCs and their progeny is particularly desirable for transplantation studies. The use of fluorescent proteins has greatly aided the investigations of protein and cell function on short-time scales.

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