bluuebunny/crossref_metadata_2025 huggingface dataset:
Anomalous seismic activity associated with 1988 Udayapur earthquake
Authors: Paudyal Harihar
Published: December 2010

The Udayapur earthquake of August 20, 1988 (Mb 6.4, Ms 6.6, Origin time: 23:09:10, epicenter at 26.8 °N 86.6 °E and Focal depth 57 km) occurred in the Himalayan front arc which caused severe damage in the region will loss of 1100 lives. In the same epicentral region, a strong event of mb 5.4 has occurred on 20 April 1988. Anomalous seismic activity associated with these earthquake in Eastern Nepal and its adjoining region in an area bounded by 26.0°-29.0° N and 84.6°-88.4° E have been studied using seismicity data from 1975-1988. The preparatory zone is delineated using the temporal and the spatial distribution of earthquakes, considering the events with cutoff magnitude mb ≥ 4.3. Based on daily number of events as well as cumulative number of earthquake with time within the preparatory zone anomalous seismicity is recognized. Accordingly four anomalous episodes: Normal/ background (N); Anomalous/ swarm (A); Precursory gap (G) and Mainshock sequence (M) are identified. It is observed that the first mainshock (mb 5.4) was related to the second mainshock (mb 6.4) which was preceded by well defined patterns of anomalous seismicity/ precursory swarm which commenced about ten years and six months prior to mainshock. Keywords: Anomalous seismicity; Central Himalaya; South Eastern Nepal; Precursory swarm DOI: 10.3126/bibechana.v7i0.4050BIBECHANA 7 (2011) 76-82
Plasma BNP as a Biomarker for Clinical Staging of Heart Failure
Authors: Hoque MM , Shafiullah S , Sultana P
Published: December 2010

Background: Accurate diagnosis and clinical staging of heart failure (HF) is essential for its proper management and logical drug therapy to reduce morbidity and mortality. On this perspective researcher are in search of a good biomarker as complementary to the clinical parameters to improve the performance of HF diagnosis and its clinical staging. B-type natriuretic peptide (BNP) secreted by cardiac ventricles in HF has emerged as a new promising biomarker in this regard. Objective of the study was evaluation of plasma BNP concentration in relation to the severity of HF and its use as a biomarker for clinical staging of HF.Methods: In a cross sectional study 100 HF cases diagnosed by clinical parameters and echocardiography were enrolled and sub grouped into NYHA classes (I, II, II & IV) depending on clinical severity and functional limitations. Plasma BNP measured in all study subjects and summarized in each of these sub groups.Results: Median plasma BNP concentration in NYHA class-I, II, III & IV found to be 82.7, 267.2, 694.8 & 1530.4pg/ml respectively with progressive rising trend and at 95% CI level the plasma BNP in different sub groups were 64.5-112.7, 214.3-293.5, 626.4-902.4 & 1443.1-2384.4pg/ml respectively.Conclusion: Plasma BNP concentration increases progressively with increasing severity of HF to make it to be used for clinical staging of the disease. In mild, moderate and severe HF plasma BNP proposed to be 100-460, 460-1170 and >1170pg/ml respectively.Keywords: BNP; Heart failure; Biomarker.  DOI: 10.3329/cardio.v2i2.6630Cardiovasc. j. 2010; 2(2) : 142-146
Percutaneous Coronary Intervention (PCI) in Patients with Chronic Total Occlusion (CTO): A Single Center Experiences
Authors: Islam AHMW , Munwar S , Talukder S , Reza AQM
Published: December 2010

Background: Aim of the study was to evaluate the primary in-hospital success and 30-days survival outcome of PCI in patients with CTO lesions, using either Bare-metal stents (BMS) or Drug Eluting Stent (DES) like Sirolimus-eluting or Paclitaxel-eluting stent in our hospital setting.Methods: Total 50 patients were randomized as per the definition of CTO, from a total of 400 patients who had PCI at our center in the quantifying period. After the guidewire crossing and the balloon dilation, measurement of the culprit lesion was done by using Siemens QCA measuring system. Among the patients, Male: 41 and Female: 9. Mean age were for Male: 53.3yrs, for Female: 64.4 yrs. Associated CAD risk factors were Dyslipidemia, High Blood pressure, Diabetes Mellitus, Positive FH for CAD and Smoking. Results: Our study results show 50 patients (12.5%) had CTO lesion out of total 400 PCI procedures. Sex distribution in male 41 (82%), Female 9 (18%). Among the study group; 38 (76%) were Dyslipidemic, 31 (62%) were hypertensive; 20 (40%) patients were Diabetic, 9 (22%) were all male smoker, 5 (10%) were having positive FH for CAD. Female patients were more obese and developed CAD in advance age (male: 53.5 Versus Female: 64.4 yrs). Average diameter of stented vessel was greater in RCA than LAD and LCX. We found that the incidences of CTO lesions were more in LAD territory 20 (40%) followed by RCA 17 (34%) and LCX 13(26%). Single vessel Disease (SVD) in 45 (90%) patients was more common type of CTO lesion followed by Double vessel disease (DVD) in 5(10%). Post procedural, in-hospital and 30 days survival out comer was 100% in our present study. Conclusion: Our study has revealed that PCI in patients with CTO lesions has increased inhospital and 30 days survival outcome, are treated with BMS or DES. The incidence of CTO lesion is more common in male than in female. Female are developing heart disease in advance age and are more obese. Keywords: Chronic total occlusion; PCI; Drug Eluting Stent; Bare Metal Stent DOI: 10.3329/cardio.v2i2.6634Cardiovasc. j. 2010; 2(2) : 168-174
Surgical Ventricular Restoration (SVR) for Ischemic Heart Failure
Authors: Chanda PK , Sharifuzzaman M , Ali S , Haque T , Ahmed F
Published: December 2010

Surgical ventricular restoration (SVR) is a surgical procedure developed in an attempt to reverse the negative remodeling that occurs following myocardial infarction. SVR has evolved from a treatment for ventricular aneurysms and has become a treatment of ischemic heart failure.SVR procedure is usually performed after coronary artery bypass grafting (CABG) and may proceed or be followed by mitral valve repair or replacement. This article will review the procedure. Keywords: Surgical Ventricular Restoration; CABG; Mitral valve repair. DOI: 10.3329/cardio.v2i2.6646Cardiovasc. j. 2010; 2(2) : 227-235
Senior Resident Training on Educational Principles (STEP): A Proposed Innovative Step from a Developing Nation
Authors: Singh Satendra
Published: December 2010

Resident-as-teacher courses are pretty common in Western medical schools however they are a rarity in Asian and developing countries. The current report is a scholarly analysis of a three day orientation program for senior residents in order to improve their functioning by providing new template either for supplementing basic workshops for faculty or to advocate a change in system. The experience gained by Medical Education Unit of University College of Medical Sciences can be used to conduct training breeding grounds at national or regional levels. Resident as teachers educational interventions need to be designed taking into account their impact on education system.
Risk Reserve Constrained Economic Dispatch Model with Wind Power Penetration
Authors: Zhou Wei , Sun Hui , Peng Yu
Published: December 2010

This paper develops a modified economic dispatch (ED) optimization model with wind power penetration. Due to the uncertain nature of wind speed, both overestimation and underestimation of the available wind power are compensated using the up and down spinning reserves. In order to determine both of these two reserve demands, the risk-based up and down spinning reserve constraints are presented considering not only the uncertainty of available wind power, but also the load forecast error and generator outage rates. The predictor-corrector primal-dual interior point (IP) method is utilized to solve the proposed ED model. Simulation results of a system with ten conventional generators and one wind farm demonstrate the effectiveness of the proposed method.
Tribenzamidomethyl Hydrazine
Authors: Tanatarec Jasmina , Mikova Bozhana , Draeger Gerald , Popovski Emil
Published: December 2010

A new tribenzamidomethyl hydrazine was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.
Positive and Negative Temperature Dependence in the Resistivity of Crystallized Zr-Fe-Ni Metallic Glasses
Authors: Hamed Fathalla
Published: December 2010

Ni0.25Fe0.75Zr3 metallic glassy ribbons were annealed in evacuated quartz ampoules beyond the crystallization temperatures (Tx ~655 K) over the range 773 to 1,173 K for varying periods of time. The resistivity of samples annealed over the temperature range 923 to 1,073 K for periods less than four hours increased as a function of decreasing temperature, while it decreased for samples annealed for more than four hours or at temperatures below 923 K or above 1,073 K for any period of time. All the annealed samples were found to contain only Ni, Fe and Zr from energy dispersive X-ray (EDX) analyses.
Evaluation of Mechanical Tomato Harvesting Using Wireless Sensors
Authors: Arazuri Silvia , Arana Ignacio , Jaren Carmen
Published: December 2010

The harvesting of processing tomatoes is fully mechanised and it is well known that during harvest, fruits are subjected to mechanical stress causing physical injuries, including skin punctures, pulp and cell rupture. Some wireless sensors have been used for research during recent years with the main purpose of reducing the quality loss of tomato fruits by diminishing the number and intensity of impacts. In this study the IRD (impact recorder device) sensor was used to evaluate several tomato harvesters. The specific objectives were to evaluate the impacts during mechanical harvest using a wireless sensor, to determine the critical points at which damage occurs, and to assess the damage levels. Samples were taken to determine the influence of mechanical harvest on texture, or on other quality characteristics including percentage of damages. From the obtained data it has been possible to identify the critical points where the damages were produced for each one of the five harvester models examined. The highest risk of damage was in zone 1 of the combine—from the cutting system to the colour selector—because the impacts were of higher intensity and hit less absorbing surfaces than in zone 2—from colour selector to discharge. The shaker and exit from the shaker are two of the harvester elements that registered the highest intensity impacts. By adjusting, in a specific way each harvester model, using the results from this research, it has been possible to reduce the tomato damage percentage from 20 to 29% to less than 10%.
Treatment of Ocular Surface Injuries by Limbal and Mesenchymal Stem Cells Growing on Nanofiber Scaffolds
Authors: Zajicova Alena , Pokorna Katerina , Lencova Anna , Krulova Magdalena , Svobodova Eliska , Kubinova Sarka , Sykova Eva , Pradny Martin , Michalek Jiri , Svobodova Jana , Munzarova Marcela , Holan Vladimir
Published: December 2010

Stem cell (SC) therapy represents a promising approach to treat a wide variety of injuries, inherited diseases, or acquired SC deficiencies. One of the major problems associated with SC therapy remains the absence of a suitable matrix for SC growth and transfer. We describe here the growth and metabolic characteristics of mouse limbal stem cells (LSCs) and mesenchymal stem cells (MSCs) growing on 3D nanofiber scaffolds fabricated from polyamide 6/12 (PA6/12). The nanofibers were prepared by the original needleless electrospun Nanospider technology, which enables to create nanofibers of defined diameter, porosity, and a basis weight. Copolymer PA6/12 was selected on the basis of the stability of its nanofibers in aqueous solutions, its biocompatibility, and its superior properties as a matrix for the growth of LSCs, MSCs, and corneal epithelial and endothelial cell lines. The morphology, growth properties, and viability of cells grown on PA6/12 nanofibers were comparable with those grown on plastic. LSCs labeled with the fluorescent dye PKH26 and grown on PA6/12 nanofibers were transferred onto the damaged ocular surface, where their seeding and survival were monitored. Cotransfer of LSCs with MSCs, which have immunosuppressive properties, significantly inhibited local inflammatory reactions and supported the healing process. The results thus show that nanofibers prepared from copolymer PA6/12 represent a convenient scaffold for growth of LSCs and MSCs and transfer to treat SC deficiencies and various ocular surface injuries.
Glutamatergic Excitation and GABA Release from a Transplantable Cell Line
Authors: Mejía-Toiber Jana , Márquez-Ramos Jose Abraham , Díaz-Muñoz Mauricio , Peña Fernando , Aguilar Manuel B. , Giordano Magda
Published: December 2010

The cell line M213-2O CL-4 was derived from cell line M213-2O and further modified to express human glutamate decarboxylase (hGAD-67), the enzyme that synthesizes GABA. Brain transplants of this cell line in animal models of epilepsy have been shown to modulate seizures. However, the mechanisms that underlie such actions are unknown. The purpose of the present study was to characterize this cell line and its responsiveness to several depolarizing conditions, in order to better understand how these cells exert their effects. Intracellular GABA levels were 34-fold higher and GAD activity was 16-fold higher in clone M213-2O CL-4 than in M213-2O. Both cell lines could take up [3H]GABA in vitro, and this uptake was prevented by nipecotic acid. By combining GABA release measurements and calcium imaging in vitro, we found that high extracellular K+, zero Mg2+, or glutamate activated M213-2O CL-4 cells and resulted in GABA release. The response to glutamate appeared to be mediated by AMPA/NMDA-like receptors. High KCl-induced GABA release was prevented when a Ca2+-free Krebs solution was used, suggesting an exocytotic-like mechanism. These results indicate that the cell line M213-2O CL-4 synthesizes, releases, and takes up GABA in vitro, and can be activated by depolarizing stimuli.
Beneficial Effects of VEGF Secreted from Stromal Cells in Supporting Endothelial Cell Functions: Therapeutic Implications for Critical Limb Ischemia
Authors: Cobellis Gilda , Maione Ciro , Botti Chiara , Coppola Antonietta , Silvestroni Andrea , Lillo Stefano , Schiavone Vincenzo , Molinari Anna Maria , Sica Vincenzo
Published: December 2010

Critical limb ischemia (CLI) is the end stage of peripheral vascular disease (PVD). One third of CLI patients progresses to leg amputation with high associated morbidity and mortality. In no-option patients with end-stage critical limb ischemia, bone marrow cell transplantation has shown promising results, improving leg perfusion to the level of reducing major amputations and allowing limb salvage. We recently reported the successful application of an innovative protocol based on repeated autologous bone marrow cell transplantation, which resulted in an effective and feasible strategy for achieving long-term revascularization in patients with severe CLI. In an effort to understand the clinical benefit provided by stem cells therapy in patients with CLI, we characterized the marrow-derived stromal cells of CLI patients and we provided a correlation between the in vitro features of these cells and the clinical follow up at 12 months. We showed that cells derived from CLI patients had a reduced capacity to proliferate, adhere, and migrate, but that they stimulated proliferation and migration of endothelial cells through the release of VEGF-A, supporting the idea that the paracrine mechanisms underpinned the biological effects of long-term angiogenesis in CLI patients.
Bone Marrow and Pancreatic Islets: An Old Story with New Perspectives
Authors: Ciceri Fabio , Piemonti Lorenzo
Published: December 2010

In the past years, in the field of β-cell replacement for diabetes therapy, the easy availability of bone marrow (BM) and the widely consolidated clinical experience in the field of hematology have contributed to the development of strategy to achieve donor-specific transplantation tolerance. Recently, the potential role of BM in diabetes therapy has been reassessed from a different point of view. Diverse groups investigated the contribution of BM cells to β-cell replacement as direct differentiation into insulin-producing cells. More importantly, while direct differentiation is highly unlikely, a wide array of experimental evidences indicates that cells of BM origin are capable of facilitating the survival or the endogenous regeneration of β-cells through an as yet well-defined regeneration process. These new experimental in vitro and in vivo data will expand in the near future the clinical trials involving BM or BM-derived cells to cure both type 1 and type 2 diabetes in humans. In this review we recapitulate the history of use of BM in diabetes therapy and we provide clinically relevant actual information about the participation of BM and BM-derived stem cells in islet cell regeneration processes. Furthermore, new aspects such as employing BM as “feeder tissue” for pancreatic islets and new clinical use of BM in diabetes therapy are discussed.
In Vitro Differentiated Adult Human Liver Progenitor Cells Display Mature Hepatic Metabolic Functions: A Potential Tool for in Vitro Pharmacotoxicological Testing
Authors: Khuu Dung Ngoc , Scheers Isabelle , Ehnert Sabrina , Jazouli Nawal , Nyabi Omar , Buc-Calderon Pedro , Meulemans Ann , Nussler Andreas , Sokal Etienne , Najimi Mustapha
Published: December 2010

The potential use of stem/progenitor cells as alternative cell sources to mature hepatocytes remains basically dependent on their ability to exhibit some, if not all, the metabolic liver functions. In the current study, four major liver functions were investigated in adult derived human liver stem/progenitor cell (ADHLSCs) populations submitted to in vitro hepatogenic differentiation: gluconeogenesis, ammonia detoxification, and activity of phase I and phase II drug-metabolizing enzymes. These acquired hepatic activities were compared to those of primary adult human hepatocytes, the standard reference. Amino acid content was also investigated after hepatogenic differentiation. Differentiated ADHLSCs display higher de novo synthesis of glucose correlated to an increased activity of glucose-6 phosphatase and mRNA expression of key related enzymes. Differentiated ADHLSCs are also able to metabolize ammonium chloride and to produce urea. This was correlated to an increase in the mRNA expression of relevant key enzymes such arginase. With respect to drug metabolism, differentiated ADHLSCs express mRNAs of all the major cytochromes investigated, among which the CYP3A4 isoform (the most important drug-metabolizing enzyme). Such increased expression is correlated to an enhanced phase I activity as independently demonstrated using fluorescence-based assays. Phase II enzyme activity and amino acid levels also show a significant enhancement in differentiated ADHLSCs. The current study, according to data independently obtained in different labs, demonstrates that in vitro differentiated ADHLSCs are able to display advanced liver metabolic functions supporting the possibility to develop them as potential alternatives to primary hepatocytes for in vitro settings.
Transplantation of Olfactory Ensheathing Cells as Adjunct Cell Therapy for Peripheral Nerve Injury
Authors: Radtke Christine , Wewetzer Konstantin , Reimers Kerstin , Vogt Peter M.
Published: December 2010

Traumatic events, such as work place trauma or motor vehicle accident violence, result in a significant number of severe peripheral nerve lesions, including nerve crush and nerve disruption defects. Transplantation of myelin-forming cells, such as Schwann cells (SCs) or olfactory ensheathing cells (OECs), may be beneficial to the regenerative process because the applied cells could mediate neurotrophic and neuroprotective effects by secretion of chemokines. Moreover, myelin-forming cells are capable of bridging the repair site by establishing an environment permissive to axonal regeneration. The cell types that are subject to intense investigation include SCs and OECs either derived from the olfactory bulb or the olfactory mucosa, stromal cells from bone marrow (mesenchymal stem cells, MSCs), and adipose tissue-derived cells. OECs reside in the peripheral and central nervous system and have been suggested to display unique regenerative properties. However, so far OECs were mainly used in experimental studies to foster central regeneration and it was not until recently that their regeneration-promoting activity for the peripheral nervous system was recognized. In the present review, we summarize recent experimental evidence regarding the regenerative effects of OECs applied to the peripheral nervous system that may be relevant to design novel autologous cell transplantation therapies.
Long-Term Contribution of Human Bone Marrow Mesenchymal Stromal Cells to Skeletal Muscle Regeneration in Mice
Authors: De La Garza-Rodea Anabel S. , Van Der Velde Ietje , Boersma Hester , Gonçalves Manuel A. F. V. , Van Bekkum Dirk W. , De Vries Antoine A. F. , Knaän-Shanzer Shoshan
Published: December 2010

Mesenchymal stromal cells (MSCs) are attractive for cellular therapy of muscular dystrophies as they are easy to procure, can be greatly expanded ex vivo, and contribute to skeletal muscle repair in vivo. However, detailed information about the contribution of bone marrow (BM)-derived human MSCs (BM-hMSCs) to skeletal muscle regeneration in vivo is very limited. Here, we present the results of a comprehensive study of the fate of LacZ-tagged BM-hMSCs following implantation in cardiotoxin (CTX)-injured tibialis anterior muscles (TAMs) of immunodeficient mice. β-Galactosidase-positive (β-gal+) human-mouse hybrid myofibers (HMs) were counted in serial cross sections over the full length of the treated TAMs of groups of mice at monthly intervals. The number of human cells was estimated using chemiluminescence assays. While the number of human cells declined gradually to about 10% of the injected cells at 60 days after transplantation, the number of HMs increased from day 10 onwards, reaching 104 ± 39.1 per TAM at 4 months postinjection. β-gal+cells and HMs were distributed over the entire muscle, indicating migration of the former from the central injection site to the ends of the TAMs. The identification of HMs that stained positive for human spectrin suggests myogenic reprogramming of hMSC nuclei. In summary, our findings reveal that BM-hMSCs continue to participate in the regeneration/remodeling of CTX-injured TAMs, resulting in ±5% HMs at 4 months after damage induction. Moreover, donor-derived cells were shown to express genetic information, both endogenous and transgenic, in recipient myofibers.
Markers of Pluripotency and Differentiation in Human Neural Precursor Cells Derived from Embryonic Stem Cells and CNS Tissue
Authors: Sundberg M. , Andersson P.-H. , Åkesson E. , Odeberg J. , Holmberg L. , Inzunza J. , Falci S. , Öhman J. , Suuronen R. , Skottman H. , Lehtimäki K. , Hovatta O. , Narkilahti S. , Sundström E.
Published: December 2010

Cell transplantation therapies for central nervous system (CNS) deficits such as spinal cord injury (SCI) have been shown to be effective in several animal models. One cell type that has been transplanted is neural precursor cells (NPCs), for which there are several possible sources. We have studied NPCs derived from human embryonic stem cells (hESCs) and human fetal CNS tissue (hfNPCs), cultured as neurospheres, and the expression of pluripotency and neural genes during neural induction and in vitro differentiation. mRNA for the pluripotency markers Nanog, Oct-4, Gdf3, and DNMT3b were downregulated during neural differentiation of hESCs. mRNA for these markers was found in nonpluripotent hfNPC at higher levels compared to hESC-NPCs. However, Oct-4 protein was found in hESC-NPCs after 8 weeks of culture, but not in hfNPCs. Similarly, SSEA-4 and CD326 were only found in hESC-NPCs. NPCs from both sources differentiated as expected to cells with typical features of neurons and astrocytes. The expressions of neuronal markers in hESC-NPCs were affected by the composition of cell culture medium, while this did not affect hfNPCs. Transplantation of hESC-NPC or hfNPC neurospheres into immunodeficient mouse testis or subcutaneous tissue did not result in tumor formation. In contrast, typical teratomas appeared in all animals after transplantation of hESC-NPCs to injured or noninjured spinal cords of immunodeficient rats. Our data show that transplantation to the subcutaneous tissue or the testes of immunodeficient mice is not a reliable method for evaluation of the tumor risk of remaining pluripotent cells in grafts.
Selective Depletion of Cross-Presenting Dendritic Cells Enhances Islet Allograft Survival
Authors: Sutherland Robyn M. , Zhan Yifan , Carrington Emma M. , Londrigan Sarah L. , Lew Andrew M.
Published: December 2010

MHC class I presentation of peptides derived from exogenous antigens (not synthesized within the antigen-presenting cell) is called cross-presentation and is mediated by selective subsets of dendritic cells (DC). A proportion of both donor and host DC may cross-present. Although there has been many studies that have investigated the role of donor versus host DC (i.e., direct vs. indirect pathway), what role cross-presenting DC play in allograft rejection has not been determined. We recently identified an agent, cytochrome c (cytc), that selectively depletes cross-presenting DC in vivo. By administering cytc we were able to study the impact of cross-presenting DC on rejection of islets grafted into fully mismatched mice. We found that cytc protected about half of the islet allografts from rejection. Our results indicate that cross-presenting DC can make potent contributions to the immune response to islet allografts, and contend that agents such as cytc that selectively target DC heralds a novel method of immunosuppression.
An Overview of Concepts for Cancer Stem Cells
Authors: Chen Shih-Yin , Huang Yu-Chuen , Liu Shih-Ping , Tsai Fuu-Jen , Shyu Woei-Cherng , Lin Shinn-Zong
Published: December 2010

For many years, cancer research has focused on the adult stem cells present in malignant tumors. It is believed that current cancer treatments sometimes fail because they do not target these cells. According to classic models of carcinogenesis, these events can occur in any cell. In contrast, the cancer stem cell (CSC) hypothesis states that the preferential targets of oncogenic transformation are tissue stem cells or early progenitor cells that have acquired the potential for self-renewal. These tumor-initiating cells, or CSCs, in turn, are characterized by their ability to undergo self-renewal, a process that drives tumorigenesis and differentiation, which contributes to the cellular heterogeneity of tumors. Herein, we discuss the definitions and properties of CSCs in the major human cancers.
High Vascular Density and Oxygenation of Pancreatic Islets Transplanted in Clusters into Striated Muscle
Authors: Svensson Johanna , Lau Joey , Sandberg Monica , Carlsson Per-Ola
Published: December 2010

Pancreatic islet transplantation is presently almost exclusively performed using the intraportal route for transplantation into the liver. However, islets at this site are poorly revascularized and, when also considering the poor long-term results of clinical islet transplantation, there has in recent years emerged an increased interest to evaluate alternative sites for islet transplantation. Striated muscle is easily accessible and has for decades been used for autotransplantation of parathyroid glands. Moreover, it is almost the only tissue in the adult where physiological angiogenesis occurs. The present study tested the hypothesis that striated muscle would provide good conditions for revascularization and oxygenation of transplanted islets. Because we previously have observed similar revascularization of islets implanted to the renal subcapsular site and intraportally into the liver, islets grafted to the kidney were for simplicity besides native islets used for comparison. Islets grafted into muscle were found to have three times more blood vessels than corresponding islets at the renal subcapsular site at 2 month follow-up, but still less vascular numbers than native islets. The oxygen tension in 2-month-old intramuscular islet grafts was sixfold higher than in corresponding renal subcapsular grafts, and 70% of that in native islets. However, the oxygenation of surrounding muscle was only 50% of that in renal cortex, and connective tissue constituted a larger proportion of the intramuscular than the renal subcapsular grafts, suggesting exaggerated early islet cell death at the former site. We conclude that the intramuscular site provides excellent conditions for vascular engraftment, but that interventions to improve early islet survival likely are needed before clinical application. Such could include bioengineered matrices that not only spatially disperse the islet, but also could provide local supply of oxygen carriers, growth and survival factors, strategies that are much more easily applied at the intramuscular than the intrahepatic site.
Differential Hematopoietic Supportive Potential and Gene Expression of Stroma Cell Lines from Midgestation Mouse Placenta and Adult Bone Marrow
Authors: Wang Yingchun , Nathanson Lubov , McNiece Ian K.
Published: December 2010

During mouse embryogenesis, hematopoietic development takes place in several distinct anatomic locations. The microenvironment of different hematopoietic organs plays an important role in the proliferation and maturation of the hematopoietic cells. We hypothesized that fetal stromal cells would be distinct to adult bone marrow (BM)-derived stromal cells because the BM contributes mainly to the homeostasis of hematopoietic stem cells (HSCs), while extensive expansion of HSCs occurs during fetal development. Here we report the establishment of stromal cell lines from fetal hematopoietic organs, namely aorta-gonad-mesonephros (AGM), midgestation placenta (PL), and fetal liver (FL) together with adult bone marrow (BM). The growth patterns and hematopoietic supportive potential were studied. Their phenotypic and molecular gene expression profiles were also determined. Stromal cell lines from each tissue were able to support cobblestone area formation of BM c-Kit+Sca-1+hematopoietic cells: 22 (22/47) from AGM, three (3/4) from PL, three (3/4) from FL, and three (3/3) from BM. There were similar levels of expansion of total mononuclear cells (TMNs) when HSCs were cocultured with fetal stroma and adult BM stroma. However, PL-derived stromal cells supported higher levels of generation of colony-forming progenitor cell (CFU-C), indicated by more colonies and colonies with significantly larger size. Flow cytometric analysis of the PL1 cells demonstrated a phenotype of CD45-, CD105+, Sca-1+, CD34+, and CD49d+, compared to adult BM1 cells, which were CD45-, CD105+, Sca-1+, CD34-, and CD49d-. Using Affymetrix microarray analysis, we identified that genes specifically express in endothelial cells, such as Tie1, Tek, Kdr, Flt4, Emcn, Pecam1, Icam2, Cdh5, Esam1, Prom1, Cd34, and Sele were highly expressed in stroma PL1, consistent with an endothelial phenotype, while BM1 expressed a mesenchymal stromal phenotype. In summary, these data demonstrate distinct characteristics of stromal cells that provide insights into the microenvironmental control of HSCs.
Pathogen Inactivation of Human Serum Facilitates its Clinical Use for Islet Cell Culture and Subsequent Transplantation
Authors: Ståhle Magnus U. , Brandhorst Daniel , Korsgren Olle , Knutson Folke
Published: December 2010

Serum is regarded as an essential supplement to promote survival and growth of cells during culture. However, the potential risk of transmitting diseases disqualifies the use of serum for clinical cell therapy in most countries. Hence, most clinical cell therapy programs have replaced human serum with human serum albumin, which can result in inferior quality of released cell products. Photochemical treatment of different blood products utilizing Intercept? technology has been shown to inactivate a broad variety of pathogens of RNA and DNA origin. The present study assesses the feasibility of using pathogen-inactivated, blood group-compatible serum for use in human pancreatic islet culture. Isolated human islets were cultured at 37°C for 3–4 days in CMRL 1066 supplemented with 10% of either pathogen-inactivated or nontreated human serum. Islet quality assessment included glucose-stimulated insulin release (perifusion), ADP/ATP ratio, cytokine expression, and posttransplant function in diabetic nude mice. No differences were found between islets cultured in pathogen-inactivated or control serum regarding stimulated insulin release, intracellular insulin content, and ADP/ATP ratio. Whether media was supplemented with treated or nontreated serum, islet expression of IL-6, IL-8, MCP-1, or tissue factor was not affected. The final diabetes-reversal rate of mice receiving islets cultured in pathogen-inactivated or nontreated serum was 78% and 87%, respectively (NS). As reported here, pathogen-inactivated human serum does not affect viability or functional integrity of cultured human islets. The implementation of this technology for RNA- and DNA-based pathogen inactivation should enable reintroduction of human serum for clinical cell therapy.
Light Deprivation Induces Depression-Like Behavior and Suppresses Neurogenesis in Diurnal Mongolian Gerbil (Meriones unguiculatus)
Authors: Lau Benson Wui-Man , Ren Chaoran , Yang Jian , Yan Sylvia W. L. , Chang Raymond Chuen-Chung , Pu Mingliang , So Kwok-Fai
Published: December 2010

Recent evidence suggests that adult neurogenesis contributes to the pathophysiology of different psychiatric disorders, including depressive disorder, anxiety disorder, and schizophrenia. Seasonal affective disorder (SAD) is a specific form of recurrent depressive disorder that can be induced by shortened light period. It is unclear yet whether neurogenesis is affected in SAD or under altered light/dark cycle. The present study aims at examining whether neurogenesis and dendritic growth of immature neurons are affected in Mongolian gerbils, a mainly diurnal rodent, under light deprivation. Animals were divided into two groups: the control (kept in 12 h light:12 h dark) and the light-deprived groups (kept in 24 h dark). Depression-like behaviors and neurogenesis were assessed after 2 weeks. Compared with the control group, light-deprived gerbils showed increased immobile time in the tail suspension test and forced swimming test, which indicates induction of depression-like behavior. Cell proliferation in both the hippocampal and subventricular zone were significantly decreased in the light-deprived group, which also showed a decreased neuronal differentiation. Dendritic maturation of immature neurons was suppressed by light deprivation, which is revealed by doublecortin staining and Sholl analysis. The results revealed that the light/dark cycle exerts impacts on neurogenesis and maturation of new neurons. Additionally, the current experiment may offer a model for exploring the relationship among daylight exposure, circadian cycles, depressive behavior, and the underlying mechanisms.
Promising Cell-Based Therapy for Bone Regeneration Using Stem Cells from Deciduous Teeth, Dental Pulp, and Bone Marrow
Authors: Yamada Yoichi , Ito Kenji , Nakamura Sayaka , Ueda Minoru , Nagasaka Tetsuro
Published: December 2010

We attempted to regenerate bone in a significant osseous defect with various stem cells from deciduous teeth, extracted from puppies, and grafted them into a parent canine mandible as an allograft, parent dental pulp, and bone marrow by tissue engineering and regenerative medicine technology using platelet-rich plasma as an autologous scaffold and signal molecules. Initially, teeth were extracted from a child and parent hybrid canine mandible region and bone marrow (canine mesenchymal stem cells; cMSCs), and parent teeth (canine dental pulp stem cells; cDPSCs), and stem cells were extracted from deciduous teeth (puppy deciduous teeth stem cells; pDTSCs). After 4 weeks, bone defects were prepared on both sides of the mandible with a trephine bar. Graft materials were implanted into these defects: 1) control (defect only), 2) platelet-rich plasma (PRP), 3) cMSCs/PRP, 4) cDPSCs/PRP, and 5) pDTSCs/PRP to investigate the effect of stem cells. The newly formed bones were evaluated by histology and histomorphometric analysis in the defects at 2, 4, and 8 weeks. According to histological observations, the cMSCs/PRP, cDPSCs/PRP, and pDTSCs/PRP groups had well-formed mature bone and neovascularization compared with the control (defect only) and PRP groups at 4 and 8 weeks, respectively, and the mineralized tissues in cMSCs/PRP, cDPSCs/PRP, and pDTSCs/PRP specimens were positive for osteocalcin at 8 weeks. Histometrically, newly formed bone areas were 19.0 ± 2.9% (control), 19.7 ± 6.0% (PRP), 52.8 ± 3.5% (cMSCs/PRP), 61.6 ± 1.3% (cDPSCs/PRP), and 54.7 ± 2.2% (pDTSCs/PRP) at 8 weeks. There were significant differences between cMSCs, cDPSCs, pDTSCs/PRP, and control and PRP groups. These results demonstrate that stem cells from deciduous teeth, dental pulp, and bone marrow with PRP have the ability to form bone, and bone formation with DTSCs might have the potential to generate a graft between a child and parent. This preclinical study could pave the way for stem cell therapy in orthopedics and oral maxillofacial reconstruction for clinical application.
In Vivo Induction of Myeloid Suppressor Cells and CD4+Foxp3+T Regulatory Cells Prolongs Skin Allograft Survival in Mice
Authors: Adeegbe D. , Serafini P. , Bronte V. , Zoso A. , Ricordi C. , Inverardi L.
Published: December 2010

Natural CD4+Foxp3+T regulatory (Treg) cells can promote transplantation acceptance across major histocompatibility complex (MHC) barriers, while myeloid-derived suppressor cells (MDSCs) inhibit effector T-cell responses in tumor-bearing mice. One outstanding issue is whether combining the potent suppressive function of MDSCs with that of Treg cells might synergistically favor graft tolerance. In the present study, we evaluated the therapeutic potential of MDSCs and natural Treg cells in promoting allograft tolerance in mice by utilizing immunomodulatory agents to expand these cells in vivo. Upon administration of recombinant human granulocyte-colony stimulating factor (G-CSF; Neupogen), or interleukin-2 complex (IL-2C), Gr-1+CD11b+MDSCs or CD4+Foxp3+Treg cells were respectively induced at a high frequency in the peripheral lymphoid compartments of treated mice. Interestingly, induced MDSCs exhibited a more potent suppressive function in vitro when compared to MDSCs from naive mice. Furthermore, in vivo coadministration of Neupogen and IL-2C induced MDSCs at percentages that were higher than those seen when either agent was administered alone, suggesting an additive effect of the two drugs. Although treatment with either IL-2C or Neupogen led to a significant delay of MHC class II disparate allogeneic donor skin rejection, the combinatorial treatment was superior to either alone. Importantly, histological assessment of surviving grafts revealed intact morphology and minimal infiltrates at 60 days posttransplant. Collectively, our findings demonstrate that concurrent induction of MDSCs and Tregs is efficacious in downmodulating alloreactive T-cell responses in a synergistic manner and highlight the therapeutic potential of these naturally occurring suppressive leukocytes to promote transplantation tolerance.
A Meta-Analysis for Comparison of the Two-Layer and University of Wisconsin Pancreas Preservation Methods in Islet Transplantation
Authors: Qin Huanying , Matsumoto Shinichi , Klintmalm Goran B. , De Vol Edward B.
Published: December 2010

Conflicting results have been reported on the effectiveness of the two-layer method (TLM) compared with the University of Wisconsin (UW) method for preserving pancreata. The objective of this study was to compile the evidence for or against any difference in human islet yield and viability between these two. PubMed (January 2000 to May 2008) and Cochran Library searches were performed and 17 studies were included for the meta-analysis. Data on donor characteristics, preservation time, and outcomes were abstracted. Studies were subgrouped based on how TLM was used (UW + TLM or TLM alone), on mean cold ischemic time (CIT) (>20 h or <20 h), and on whether special chemical was used (yes or no). Meta-analysis of all studies and subgroups was performed and the pooled standardized mean differences (SMD) with 95% confidence intervals (CI) were reported. Overall, the use of TLM significantly increased islet yield [SMD, 0.74 (0.44–1.04)] and viability [SMD, 0.63 (0.14–1.12)]. The beneficial effects of TLM on islet yield were more evident when TLM was used following UW storage or when prolonged CIT was used. TLM used alone, shorter CIT, and no chemical use all resulted in similar islet viability between TLM and UW groups. Beneficial effects of TLM on islet viability were demonstrated only when TLM was used following UW storage, or with prolonged CIT, or with chemical use. In conclusion, the TLM was beneficial for prolonged pancreas preservation before human islet isolation; however, benefit of the TLM for short-term preservation was not clear.
Effect of Splenectomy on Pancytopenia after a Peripheral Blood Stem Cell Transplantation
Authors: Ding Jiahua , Bao Wen , Wang Jun , Zhao Gang , Chen Jian , Song Huihui
Published: December 2010

To analyze the effect of a splenectomy on pancytopenia after a peripheral blood stem cell transplantation (PBSCT) in chronic myeloid leukemia (CML) patients. Three CML patients diagnosed with splenomegaly in our department from 2002 to 2006 received a splenectomy after PBSCT. Patient 1, a 42-year-old male in chronic phase (CP), received an HLA-identical sibling allo-PBSCT. Patient 2, a 28-year-old female in aggressive phase (AP), received a PBSCT from her twin. Patient 3, a 26-year-old male in chronic phase (CP), received a PBSCT from an unrelated donor. The conditioning regimen included busulfan and cyclophosphamide (BU/CY2). Patients 1, 2, and 3 received splenectomies on days 168, 51, and 114, respectively. Bcr-abl transcripts were detected using the polymerase chain reaction (PCR). Chimerism was documented by PCR amplification of a variable number of tandem repeat (VNTR) polymorphrisms. Neither metrisone (2 mg/kg/day for 7 days), mycophenolic acid (MMF) (0.5 g twice daily for 1 month), high-dose γ-globulin (0.4 g/kg/day for 5 days), granulocyte colony-stimulating factor (G-CSF) therapy, nor erythropoietin (EPO) therapy had produced post-PBSCT hematopoiesis recovery. Patients 1 and 2 had 5% Ph-positive chromosomes while patient 3 exhibited graft-versus-host disease (GVHD). After receiving the splenectomy, all three had a rapid hematopoeitic recovery with no evidence of Ph-positive chromosomes, and patients 1 and 3 showed complete donor chimerism (CDC). Patient 1 developed chronic GVHD (cGVHD) on day 210 postsplenectomy that was treated successfully with prednisone. Patient 2 had acute GVHD on day 55 that was treated successfully with dexamethasone (10 mg), administered intravenously once a day for 3 days with good clinical response. To date, patients 1, 2, and 3 have survived postprocedure for 85, 49, and 25 months, respectively. Splenectomy is an effective option for the patients who have pancytopenia after PBSCT and the patients recovered a good graft function after splenectomy without procedure-related complication and with long-time survival. GVHD can develop in both allo-PBSCT and syngeneic PBSCT. A splenectomy after PBSCT may increase the risk of GVHD, enhance the effect of graft versus leukemia (GVL), promote CDC formation.
NUP98-HOXA10hd-Expanded Hematopoietic Stem Cells Efficiently Reconstitute Bone Marrow of Mismatched Recipients and Induce Tolerance
Authors: Even Y. , Bennett J. L. , Sekulovic S. , So L. , Yi L. , McNagny K. , Humphries R. K. , Rossi F. M. V.
Published: December 2010

Gene therapy as well as methods capable of returning cells to a pluripotent state (iPS) have enabled the correction of genetic deficiencies in syngenic adult progenitors, reducing the need for immunosuppression in cell therapy approaches. However, in diseases involving mutations that lead to the complete lack of a protein, such as Duchenne muscular dystrophy, the main immunogens leading to rejection of transplanted cells are the therapeutic proteins themselves. In these cases even iPS cells would not circumvent the need for immunosuppression, and alternative strategies must be developed. One such potential strategy seeks to induce immune tolerance using hematopoietic stem cells originated from the same donor or iPS line from which the therapeutic progenitors are derived. However, donor hematopoietic stem cells (HSCs) are available in limiting numbers and embryonic stem (ES) cell-derived HSCs engraft poorly in adults. While these limitations have been circumvented by ectopic expression of HOXB4, overexpression of this protein is associated with inefficient lymphoid reconstitution. Here we show that adult HSCs expanded with a NUP98-HOXA10hd fusion protein sustain long-term engraftment in immunologically mismatched recipients and generate normal numbers of lymphoid cells. In addition, NUP98-HOXA10hd-expanded cells induce functional immune tolerance to a subsequent transplant of myogenic progenitors immunologically matched with the transplanted HSCs.
Intracerebroventricular Transplantation of Cord Blood-Derived Neural Progenitors in a Child with Severe Global Brain Ischemic Injury
Authors: Jozwiak Sergiusz , Habich Aleksandra , Kotulska Katarzyna , Sarnowska Anna , Kropiwnicki Tomasz , Janowski Miroslaw , Jurkiewicz Elzbieta , Lukomska Barbara , Kmiec Tomasz , Walecki Jerzy , Roszkowski Marcin , Litwin Mieczyslaw , Oldak Tomasz , Boruczkowski Dariusz , Domanska-Janik Krystyna
Published: December 2010

Transplantation of neural stem/precursor cells has recently been proposed as a promising, albeit still controversial, approach to brain repair. Human umbilical cord blood could be a source of such therapeutic cells, proven beneficial in several preclinical models of stroke. Intracerebroventricular infusion of neutrally committed cord blood-derived cells allows their broad distribution in the CNS, whereas additional labeling with iron oxide nanoparticles (SPIO) enables to follow the fate of engrafted cells by MRI. A 16-month-old child at 7 months after the onset of cardiac arrest-induced global hypoxic/ischemic brain injury, resulting in a permanent vegetative state, was subjected to intracerebroventricular transplantation of the autologous neutrally committed cord blood cells. These cells obtained by 10-day culture in vitro in neurogenic conditions were tagged with SPIO nanoparticles and grafted monthly by three serial injections (12 × 106cells/0.5 ml) into lateral ventricle of the brain. Neural conversion of cord blood cells and superparamagnetic labeling efficiency was confirmed by gene expression, immunocytochemistry, and phantom study. MRI examination revealed the discrete hypointense areas appearing immediately after transplantation in the vicinity of lateral ventricles wall with subsequent lowering of the signal during entire period of observation. The child was followed up for 6 months after the last transplantation and his neurological status slightly but significantly improved. No clinically significant adverse events were noted. This report indicates that intracerebroventricular transplantation of autologous, neutrally committed cord blood cells is a feasible, well tolerated, and safe procedure, at least during 6 months of our observation period. Moreover, a cell-related MRI signal persisted at a wall of lateral ventricle for more than 4 months and could be monitored in transplanted brain hemisphere.