Examining the Impact of Professional Learning Communities on School Performance

Implementing the principles of a professional learning community (PLC) in public schools has become a popular strategy for meeting school quality and accountability expectations. Whether PLC implementation results in improved school ratings represents a gap in the literature. Three out of the 4 elementary schools in the participating school district experienced a significant drop in state ratings. The purpose of this quantitative study was to explore the relationship between the perceived depth of implementaiton of PLCs and a school\u27s performance in terms of state ratingsGuided by the theory of the learning organization, this quantitative study was designed to identify the extent to which participants believed their schools operate as PLCs and to determine whether there is a significant difference in results between the participating schools. Participant perceptions of PLC implementation were measured through the Professional Learning Communities Assessment-Revised survey instrument. A total of 77 teachers across the 4 schools participated, and descriptive statistics were used to measure the level of PLC implementation. A one-way ANOVA was conducted to determine if there was significant differences in responses from the schools. The ANOVA revealed no significant differences in the responses between the school that did not experience a drop in ratings and the other schools. The results of this study could provide a framework to aid teachers and administrators to improve student learning by providing improved instruction. Quality instruction can lead to improved student learnings, and when student outcomes are improved, more students graduate and become productive members of their communities

Hematopoietic stem cell transplantation in children with acute leukemia: similar outcomes in recipients of umbilical cord blood versus marrow or peripheral blood stem cells from related or unrelated donors

PurposeThis study compared outcomes in children with acute leukemia who underwent transplantations with umbilical cord blood (UCB), bone marrow, or peripheral blood stem cells from a human leukocyte antigen (HLA)-matched related donor (MRD) or an unrelated donor (URD).MethodsThis retrospective study included consecutive acute leukemia patients who underwent their first allogeneic hematopoietic stem cell transplantation (HSCT) at Samsung Medical Center between 2005 and 2010. Patients received stem cells from MRD (n=33), URD (n=46), or UCB (n=41).ResultsNeutrophil and platelet recovery were significantly longer after HSCT with UCB than with MRD or URD (P<0.01 for both). In multivariate analysis using the MRD group as a reference, the URD group had a significantly higher risk of grade III to IV acute graft-versus-host disease (GVHD; relative risk [RR], 15.2; 95% confidence interval [CI], 1.2 to 186.2; P=0.03) and extensive chronic GVHD (RR, 6.9; 95% CI, 1.9 to 25.2; P<0.01). For all 3 donor types, 5-year event-free survival (EFS) and overall survival were similar. Extensive chronic GVHD was associated with fewer relapses (RR, 0.1; 95% CI, 0.04 to 0.6; P<0.01). Multivariate analysis showed that lower EFS was associated with advanced disease at transplantation (RR, 3.2; 95% CI, 1.3 to 7.8; P<0.01) and total body irradiation (RR, 2.1; 95% CI, 1.0 to 4.3; P=0.04).ConclusionSurvival after UCB transplantation was similar to survival after MRD and URD transplantation. For patients lacking an HLA matched donor, the use of UCB is a suitable alternative

Expansion of Cord Blood CD34+ Cells in Presence of zVADfmk and zLLYfmk Improved Their In Vitro Functionality and In Vivo Engraftment in NOD/SCID Mouse

BACKGROUND: Cord blood (CB) is a promising source for hematopoietic stem cell transplantations. The limitation of cell dose associated with this source has prompted the ex vivo expansion of hematopoietic stem and progenitor cells (HSPCs). However, the expansion procedure is known to exhaust the stem cell pool causing cellular defects that promote apoptosis and disrupt homing to the bone marrow. The role of apoptotic machinery in the regulation of stem cell compartment has been speculated in mouse hematopoietic and embryonic systems. We have consistently observed an increase in apoptosis in the cord blood derived CD34(+) cells cultured with cytokines compared to their freshly isolated counterpart. The present study was undertaken to assess whether pharmacological inhibition of apoptosis could improve the outcome of expansion. METHODOLOGY/PRINCIPAL FINDINGS: CB CD34(+) cells were expanded with cytokines in the presence or absence of cell permeable inhibitors of caspases and calpains; zVADfmk and zLLYfmk respectively. A novel role of apoptotic protease inhibitors was observed in increasing the CD34(+) cell content of the graft during ex vivo expansion. This was further reflected in improved in vitro functional aspects of the HSPCs; a higher clonogenicity and long term culture initiating potential. These cells sustained superior long term engraftment and an efficient regeneration of major lympho-myeloid lineages in the bone marrow of NOD/SCID mouse compared to the cells expanded with growth factors alone. CONCLUSION/SIGNIFICANCE: Our data show that, use of either zVADfmk or zLLYfmk in the culture medium improves expansion of CD34(+) cells. The strategy protects stem cell pool and committed progenitors, and improves their in vitro functionality and in vivo engraftment. This observation may complement the existing protocols used in the manipulation of hematopoietic cells for therapeutic purposes. These findings may have an impact in the CB transplant procedures involving a combined infusion of unmanipulated and expanded grafts

Acellular Bone Marrow Extracts Significantly Enhance Engraftment Levels of Human Hematopoietic Stem Cells in Mouse Xeno-Transplantation Models

Hematopoietic stem cells (HSC) derived from cord blood (CB), bone marrow (BM), or mobilized peripheral blood (PBSC) can differentiate into multiple lineages such as lymphoid, myeloid, erythroid cells and platelets. The local microenvironment is critical to the differentiation of HSCs and to the preservation of their phenotype in vivo. This microenvironment comprises a physical support supplied by the organ matrix as well as tissue specific cytokines, chemokines and growth factors. We investigated the effects of acellular bovine bone marrow extracts (BME) on HSC in vitro and in vivo. We observed a significant increase in the number of myeloid and erythroid colonies in CB mononuclear cells (MNC) or CB CD34+ cells cultured in methylcellulose media supplemented with BME. Similarly, in xeno-transplantation experiments, pretreatment with BME during ex-vivo culture of HSCs induced a significant increase in HSC engraftment in vivo. Indeed, we observed both an increase in the number of differentiated myeloid, lymphoid and erythroid cells and an acceleration of engraftment. These results were obtained using CB MNCs, BM MNCs or CD34+ cells, transplanted in immuno-compromised mice (NOD/SCID or NSG). These findings establish the basis for exploring the use of BME in the expansion of CB HSC prior to HSC Transplantation. This study stresses the importance of the mechanical structure and soluble mediators present in the surrounding niche for the proper activity and differentiation of stem cells

Pharmacological Inhibition of Caspase and Calpain Proteases: A Novel Strategy to Enhance the Homing Responses of Cord Blood HSPCs during Expansion

Background: Expansion of hematopoietic stem/progenitor cells (HSPCs) is a well-known strategy employed to facilitate the transplantation outcome. We have previously shown that the prevention of apoptosis by the inhibition of cysteine proteases, caspase and calpain played an important role in the expansion and engraftment of cord blood (CB) derived HSPCs. We hypothesize that these protease inhibitors might have maneuvered the adhesive and migratory properties of the cells rendering them to be retained in the bone marrow for sustained engraftment. The current study was aimed to investigate the mechanism of the homing responses of CB cells during expansion. Methodology/Principal Findings: CB derived CD34 + cells were expanded using a combination of growth factors with and without Caspase inhibitor-zVADfmk or Calpain 1 inhibitor- zLLYfmk. The cells were analyzed for the expression of homingrelated molecules. In vitro adhesive/migratory interactions and actin polymerization dynamics of HSPCs were assessed. In vivo homing assays were carried out in NOD/SCID mice to corroborate these observations. We observed that the presence of zVADfmk or zLLYfmk (inhibitors) caused the functional up regulation of CXCR4, integrins, and adhesion molecules, reflecting in a higher migration and adhesive interactions in vitro. The enhanced actin polymerization and the RhoGTPase protein expression complemented these observations. Furthermore, in vivo experiments showed a significantly enhanced homing to the bone marrow of NOD/SCID mice

The role and potential of umbilical cord blood in an era of new therapies: a review

In light of pioneering findings in the 1980s and an estimation of more than 130 million global annual births, umbilical cord blood (UCB) is considered to be the most plentiful reservoir of cells and to have regenerative potential for many clinical applications. Although UCB is used mainly against blood disorders, the spectrum of diseases for which it provides effective therapy has been expanded to include non-hematopoietic conditions; UCB has also been used as source for regenerative cell therapy and immune modulation. Thus, collection and banking of UCB-derived cells have become a popular option. However, there are questions regarding the cost versus the benefits of UCB banking, and it also raises complex ethical and legal issues. This review discusses many issues surrounding the conservation of UCB-derived cells and the great potential and current clinical applications of UCB in an era of new therapies. In particular, we describe the practical issues inherent in UCB collection, processing, and long-term storage as well as the different types of ‘stem’ or progenitor cells circulating in UCB and their uses in multiple clinical settings. Given these considerations, the trend toward UCB will continue to provide growing assistance to health care worldwide

The relationship between friendship transition and conflict.

The transition from acquaintanceship to friendship was examined in this study.In particular,the study focused on the development of friendship and how situations that may invite conflict affect that process.Participants were assigned to one of three relationship conditions(exchange,pre-friendship,communal) and read about a negative(conflict) and positive(non-conflict)scenario involving the assigned relationship partner.Each participant reported how he or she would feel in the imagined situations.The results of this study showed differences between the pre-friendship conditions and exchange and communal conditions.There is a pre-friendship condition felt as comfortable with the other's behavior as friends,and attributed their negative behavior to unstable,situational conditions,as is done for friends but reported that the behavior of pre-friends was more important to their relationship.This research suggests that pre-relationship is a distinct type of relationship in which a person thinks of their partners as a friends,but do not feel like friends,and attend to interactions in order to assess the status of the relationship.These findings expand our understanding of the process of friendship formation,but raise questions about the adequacy of traditional models of social relationships.Danielle R JaroscakSheets, VirgilAnderson, VeanneMaster of ArtsDepartment of PsychologyCunningham Memorial library, Terre Haute,Indiana State UniversityILL-ETD-035MastersTitle from document title page. Document formatted into pages: contains 56 p.: ill. Includes abstract and appendix