bluuebunny/crossref_metadata_2025_split huggingface dataset:
Circulating Bone Marrow-Derived Osteoblast Progenitor Cells Are Recruited to the Bone-Forming Site by the CXCR4/Stromal Cell-Derived Factor-1 Pathway
Authors: Otsuru Satoru , Tamai Katsuto , Yamazaki Takehiko , Yoshikawa Hideki , Kaneda Yasufumi 
Published: October 2007

Abstract
Previous studies demonstrated the existence of osteoblastic cells in circulating blood. Recently, we reported that osteoblast progenitor cells (OPCs) in circulation originated from bone marrow and contributed to the formation of ectopic bone induced by implantation of a bone morphogenetic protein (BMP)-2-containing collagen pellet in mouse muscular tissue. However, the character of circulating bone marrow-derived osteoblast progenitor cells (MOPCs) and the precise mechanisms involving the circulating MOPCs in the osteogenic processes, such as signals that recruit the circulating MOPCs to the osseous tissues, have been obscure. In this report, we demonstrated for the first time that the MOPCs were mobilized from intact bones to transiently occupy approximately 80% of the mononuclear cell population in the circulating blood by BMP-2-pellet implantation. The mobilized MOPCs in the circulation did not express the hematopoietic marker CD45 on their surface, but they expressed CD44 and CXCR4, receptors of osteopontin and stromal cell-derived factor-1 (SDF-1), respectively. The MOPCs isolated from the mouse peripheral blood showed the ability to be osteoblasts in vitro and in vivo. Furthermore, the MOPCs in the circulation efficiently migrated to the region of bone formation by chemoattraction of SDF-1 expressed in vascular endothelial cells and the de novo osteoblasts of the region. These data may provide a novel insight into the mechanism of bone formation involving MOPCs in circulating blood, as well as perspective on the use of circulating MOPCs to accelerate bone regeneration in the future.
Disclosure of potential conflicts of interest is found at the end of this article.
Rapid Adhesion to Collagen Isolates Murine Keratinocytes with Limited Long-Term Repopulating Ability In Vivo Despite High Clonogenicity In Vitro
Authors: Strachan Lauren R. , Scalapino Kenneth J. , Lawrence H. Jeffery , Ghadially Ruby 
Published: October 2007

Abstract
A prevalent belief in epidermal biology is that stem cells are highly clonogenic; that is, they have the ability to produce many large colonies in vitro. However, it has been well-established in hematology, and recently suggested in epithelial biology, that short-term in vitro clonogenic assays may not be reliable predictors of long-term in vivo repopulating ability. Numerous groups have shown that rapid adhesion to collagen selects for highly clonogenic keratinocytes, but it has not been demonstrated whether this subpopulation is enriched in stem cells as defined by long-term repopulating ability in vivo. We found that although rapid adhesion to collagen (within 5 minutes) selected for cells with increased short-term colony forming ability in vitro, these cells were not enriched in long-term proliferative ability in vitro or in repopulating ability in vivo after 9 weeks. Conversely, keratinocytes that did not adhere to collagen (after 20 minutes) were less clonogenic in short-term assays but possessed equivalent long-term proliferative ability in vitro and superior long-term repopulating ability in vivo. Both the rapidly adherent cell and not rapidly adherent cell populations contained small, noncomplex basaloid cells, expressed integrin α2 (a collagen IV receptor), and expressed the putative epidermal stem cell phenotype integrin α6hiCD71lo. Our results indicate that the superior short-term colony forming ability of collagen-adherent murine keratinocytes does not correlate with long-term repopulating ability in vitro or in vivo and that proliferation in vitro is not a reliable surrogate for stem cell behavior in vivo.
Disclosure of potential conflicts of interest is found at the end of this article.
Age- and Dose-Related Effects on MSC Engraftment Levels and Anatomical Distribution in the Central Nervous Systems of Nonhuman Primates: Identification of Novel MSC Subpopulations That Respond to Guidance Cues in Brain
Authors: Isakova Iryna A. , Baker Kate , DuTreil Maria , Dufour Jason , Gaupp Dina , Phinney Donald G. 
Published: October 2007

Abstract
Mesenchymal stem cells (MSCs) have demonstrated efficacy as therapeutic vectors in rodent models of neurological diseases, but few studies have evaluated their safety and efficacy in a relevant large animal model. Previously, we reported that MSCs transplanted to the central nervous systems (CNS) of adult rhesus macaques engrafted at low levels without adversely affecting animal health, behavior, or motor function. Herein, we injected MSCs intracranially into 10 healthy infant macaques and quantified their engraftment levels and mapped their anatomical distribution in brain by real-time polymerase chain reaction using an sry gene-specific probe. These analyses revealed that MSC engraftment levels in brain were on average 18-fold higher with a maximal observed difference of 180-fold in neonates as compared with that reported previously for young adult macaques. Moreover, engraftment levels were 30-fold higher after injection of a low versus high cell dose and engrafted MSCs were nonrandomly distributed throughout the infant brain and localized to specific anatomical regions. Identification of unique subpopulations of macaque and human MSCs that express receptor proteins known to regulate tangential migration of interneurons may explain their migration patterns in brain. Extensive monitoring of infant transplant recipients using a battery of age appropriate tests found no evidence of any long-term adverse effects on the health or social, behavioral, cognitive, or motor abilities of animals up to 6 months post-transplant. Therefore, direct intracranial injection represents a safe means to deliver therapeutic levels of MSCs to the CNS. Moreover, expressed guidance receptors on MSC subpopulations may regulate migration of cells in the host brain.
Disclosure of potential conflicts of interest is found at the end of this article.
Human Leukocyte Antigen-G5 Secretion by Human Mesenchymal Stem Cells Is Required to Suppress T Lymphocyte and Natural Killer Function and to Induce CD4+CD25highFOXP3+ Regulatory T Cells
Authors: Selmani Zohair , Naji Abderrahim , Zidi Ines , Favier Benoit , Gaiffe Emilie , Obert Laurent , Borg Christophe , Saas Philippe , Tiberghien Pierre , Rouas-Freiss Nathalie , Carosella Edgardo D. , Deschaseaux Frederic 
Published: October 2007

AbstractAdult bone marrow-derived mesenchymal stem cells (MSCs) are multipotent cells that are the subject of intense investigation in regenerative medicine. In addition, MSCs possess immunomodulatory properties with therapeutic potential to prevent graft-versus-host disease (GvHD) in allogeneic hematopoietic cell transplantation. Indeed, MSCs can inhibit natural killer (NK) function, modulate dendritic cell maturation, and suppress allogeneic T-cell response. Here, we report that the nonclassic human leukocyte antigen (HLA) class I molecule HLA-G is responsible for the immunomodulatory properties of MSCs. Our data show that MSCs secrete the soluble isoform HLA-G5 and that such secretion is interleukin-10-dependent. Moreover, cell contact between MSCs and allostimulated T cells is required to obtain a full HLA-G5 secretion and, as consequence, a full immunomodulation from MSCs. Blocking experiments using neutralizing anti-HLA-G antibody demonstrate that HLA-G5 contributes first to the suppression of allogeneic T-cell proliferation and then to the expansion of CD4+CD25highFOXP3+ regulatory T cells. Furthermore, we demonstrate that in addition to their action on the adaptive immune system, MSCs, through HLA-G5, affect innate immunity by inhibiting both NK cell-mediated cytolysis and interferon-γ secretion. Our results provide evidence that HLA-G5 secreted by MSCs is critical to the suppressive functions of MSCs and should contribute to improving clinical therapeutic trials that use MSCs to prevent GvHD.Disclosure of potential conflicts of interest is found at the end of this article.
Revisiting OCT4 Expression in Peripheral Blood Mononuclear Cells
Authors: Kotoula Vassiliki , Papamichos Spyros I. , Lambropoulos Alexandros F. 
Published: October 2007

Abstract
The transcription factor OCT4 (officially POU5F1; alternatively OCT3, OCT3/4, OTF3, and OTF4) is currently considered a main regulator of human embryonic stem cell pluripotency and self-renewal capacities. Importantly, these stemness properties are attributed to OCT4A, which is one of the two isoforms produced by the OCT4 gene. The second OCT4 isoform, OCT4B, does not share the stemness factor characteristics of OCT4A and is currently considered of unknown function. Hence, when investigating OCT4 expression at the mRNA and protein level, it is important to specify which OCT4 isoform is detected by the applied methods, such as polymerase chain reaction assays and immunocytochemistry antibodies. Here, we discuss the need to distinguish between OCT4A and OCT4B when interpreting OCT4 expression in differentiated cells, such as peripheral blood mononuclear cells.
Disclosure of potential conflicts of interest is found at the end of this article.
Further Evidence of a Primary, Causal Association of the PTPN22 620W Variant With Type 1 Diabetes
Authors: Zoledziewska Magdalena , Perra Chiara , Orrù Valeria , Moi Loredana , Frongia Paola , Congia Mauro , Bottini Nunzio , Cucca Francesco 
Published: October 2007

OBJECTIVE— The minor allele of the nonsynonymous single nucleotide polymorphism (SNP) +1858C&gt;T within the PTPN22 gene is positively associated with type 1 diabetes and other autoimmune diseases. Genetic and functional data underline its causal effect, but some studies suggest that this polymorphism does not entirely explain disease association of the PTPN22 region. The aim of this study was to evaluate type 1 diabetes association within this gene in the Sardinian population.
RESEARCH DESIGN AND METHODS— We resequenced the exons and potentially relevant portions of PTPN22 and detected 24 polymorphisms (23 SNPs and 1 deletion insertion polymorphism [DIP]), 8 of which were novel. A representative set of 14 SNPs and the DIP were sequentially genotyped and assessed for disease association in 794 families, 490 sporadic patients, and 721 matched control subjects.
RESULTS— The +1858C&gt;T variant, albeit rare in the general Sardinian population (allele frequency 0.014), was positively associated with type 1 diabetes (Pone tail = 3.7 × 10−3). In contrast, the background haplotype in which this mutation occurred was common (haplotype frequency 0.117) and neutrally associated with disease. We did not confirm disease associations reported in other populations for non +1858C&gt;T variants (rs2488457, rs1310182, and rs3811021), although they were present in appreciable frequencies in Sardinia. Additional weak disease associations with rare variants were detected in the Sardinian families but not confirmed in independent case-control sample sets and are most likely spurious.
CONCLUSIONS— We provide further evidence that the +1858C&gt;T polymorphism is primarily associated with type 1 diabetes and exclude major contributions from other purportedly relevant variants within this gene.
Evidence That Processes Other Than Gluconeogenesis May Influence the Ratio of Deuterium on the Fifth and Third Carbons of Glucose
Authors: Bock Gerlies , Schumann William C. , Basu Rita , Burgess Shawn C. , Yan Zheng , Chandramouli Visvanathan , Rizza Robert A. , Landau Bernard R. 
Published: October 2007

OBJECTIVE—The deuterated water method uses the ratio of deuterium on carbons 5 and 2 (C5/C2) or 3 and 2 (C3/C2) to estimate the fraction of glucose derived from gluconeogenesis. The current studies determined whether C3 and C5 glucose enrichment is influenced by processes other than gluconeogenesis.
RESEARCH DESIGN AND METHODS—Six nondiabetic subjects were infused with [3,5-2H2]glucose and insulin while glucose was clamped at ∼5 mmol/l; the C5-to-C3 ratio was measured in the in UDP-glucose pool using nuclear magnetic resonance and the acetaminophen glucuronide method.
RESULTS—Whereas the C5-to-C3 ratio of the infusate was 1.07, the ratio in UDP-glucose was &lt;1.0 in all subjects both before (0.75 ± 0.07) and during (0.67 ± 0.05) the insulin infusion.
CONCLUSIONS—These data indicate that the deuterium on C5 of glucose is lost more rapidly relative to the deuterium on C3. The decrease in the C5-to-C3 ratio could result from exchange of the lower three carbons of fructose-6-phosphate with unlabeled three-carbon precursors via the transaldolase reaction and/or selective retention of the C3 deuterium at the level of triosephosphate isomerase due to a kinetic isotope effect. After ingestion of 2H2O, these processes would increase the enrichment of C5 and decrease the enrichment of C3, respectively, with the former causing an overestimation of gluconeogenesis using the C2-to-C5 ratio and the latter an underestimation using the C3-to-C2 ratio. Future studies will be required to determine whether the impact of these processes on the measurement of gluconeogenesis differs among the disease states being evaluated (e.g., diabetes or obesity).
Inactivation of Glyceraldehyde-3-Phosphate Dehydrogenase by Fumarate in Diabetes
Authors: Blatnik Matthew , Frizzell Norma , Thorpe Suzanne R. , Baynes John W. 
Published: October 2007

OBJECTIVE—S-(2-succinyl)cysteine (2SC) is formed by a Michael addition reaction of the Krebs cycle intermediate, fumarate, with cysteine residues in protein. We investigated the role of fumarate in chemical modification and inhibition of the sulfhydryl enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in vitro and in tissues of diabetic rats.
RESEARCH DESIGN AND METHODS—GAPDH was incubated with fumarate in PBS to assess effects of fumarate on enzyme activity in vitro. Sites of 2SC formation were determined by analysis of tryptic peptides by high-performance liquid chromatography–quadrupole/time-of-flight mass spectrometry. 2SC and fumarate in gastrocnemius muscle of control and streptozotocin-induced diabetic rats were measured by liquid chromatography/tandem mass spectrometry and by gas chromatography/mass spectrometry, respectively. GAPDH was isolated from muscle by immunoprecipitation, and sites of modification of GAPDH were determined by mass spectrometry analysis.
RESULTS—2SC was found, both in vitro and in vivo, about equally at active-site Cys-149 and nucleophilic Cys-244. Inactivation of GAPDH by fumarate in vitro correlated with formation of 2SC. In diabetic compared with control rats, fumarate and 2SC concentration increased approximately fivefold, accompanied by an ∼25% decrease in GAPDH specific activity. The fractional modification of GAPDH by 2SC was significantly increased in diabetic versus control animals, consistent with the decreased specific activity of GAPDH in muscle of diabetic animals.
CONCLUSIONS—Fumarate contributes to inactivation of GAPDH in diabetes. 2SC may be a useful biomarker of mitochondrial stress in diabetes. Modification of GAPDH and other enzymes and proteins by fumarate may contribute to the metabolic changes underlying the development of diabetes complications.
Hybrid adaptive predictive control for a dynamic pickup and delivery problem including traffic congestion
Authors: Cortés Cristián E. , Núñez Alfredo , Sáez Doris 
Published: October 2007

AbstractThis paper presents a hybrid adaptive predictive control approach to incorporate future information regarding unknown demand and expected traffic conditions, in the context of a dynamic pickup and delivery problem with fixed fleet size. As the routing problem is dynamic, several stochastic effects have to be considered within the analytical expression of the dispatcher assignment decision objective function. This paper is focused on two issues: one is the extra cost associated with potential rerouting arising from unknown requests in the future, and the other is the potential uncertainty in travel time coming from non‐recurrent traffic congestion from unexpected incidents.These effects are incorporated explicitly in the objective function of the hybrid predictive controller. In fact, the proposed predictive control strategy is based on a multivariable model that includes both discrete/integer and continuous variables. The vehicle load and the sequence of stops correspond to the discrete/integer variable, adding the vehicle position as an indicator of the traffic congestion conditions. The strategy is analyzed under two scenarios. The first one considers a predictable congestion obtained using historical data (off‐line method) requiring a predictive model of velocities distributed over zones. The second scenario that accepts unpredictable congestion events generates a more complex problem that is managed by using both fault detection and isolation and fuzzy fault‐tolerant control approaches. Results validating these approaches are presented through a simulated numerical example. Copyright © 2007 John Wiley & Sons, Ltd.
Fatal lung fibrosis associated with immunodeficiency and gonadal dysgenesis in 46XX sisters—A new syndrome
Authors: Somech Raz , Somers Gino R. , Chitayat David , Grunebaum Eyal , Atkinson Adelle , Kolomietz Elena , Roifman Chaim M 
Published: October 2007

AbstractInherited immune deficiencies are a heterogeneous group of diseases that can be either isolated, with the immune defect being the exclusive manifestation, or associated with other abnormalities. We report on two sisters, born to consanguineous parents of Sri‐Lankan descent, who presented in infancy with immunodeficiency, gonadal dysgenesis, and fatal lung fibrosis. Immune studies demonstrated combined humoral and cellular abnormalities including reduced immunoglobulin production, an absence of lymphoid tissue, markedly reduced T‐lymphocyte numbers and function and reduced newly thymus‐derived T‐cells. Both infants succumbed to rapidly progressive lung fibrosis. Autopsy showed dysgenetic gonads bearing no discernible oocytes. In both, karyotypes were normal female (46,XX). Comparative genome hybridization and analysis of genes known to be associated with severe immune defects in infancy or gonadal dysgenesis showed no abnormality. The distinct findings in these two sisters have not been reported before and thus suggest a hitherto unknown autosomal recessive condition that includes immune dysfunction, gonadal dysgenesis, and pulmonary fibrosis. © 2007 Wiley‐Liss, Inc.
Materials selection and residual solvent retention in biodegradable electrospun fibers
Authors: Nam Jin , Huang Yan , Agarwal Sudha , Lannutti John 
Published: October 2007

AbstractElectrospun tissue engineering scaffolds provide mechanical support to seeded cells that populate the structure while depositing specific extracellular matrix components. The potent sterilizing agent 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) is often used in electrospinning investigations involving biologically‐derived polymers. Surprisingly, there has been no study of solvent retention versus composition even though materials selection should influence organic solvent content. We developed a method quantifying HFIP retention following electrospinning of gelatin, polycaprolactone (PCL), and PCL‐gelatin blends using electro‐spray mass spectroscopy. The acetone content of acetone‐spun PCL was also established. Pure gelatin fiber contained as much as 1600 ppm of HFIP. In contrast, little acetone or HFIP was detected in 100% PCL. Gelatin clearly has a greater affinity for HFIP than PCL and materials selection has a strong influence on the amount of retained solvent. Vacuum + heat treatment at 37 and 45ºC reduced [HFIP] to 10 and 5.6 ppm, respectively, levels having no demonstrated effects on mammalian cell viability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation and properties of physically crosslinked sodium carboxymethylcellulose/poly(vinyl alcohol) complex hydrogels
Authors: Xiao Congming , Gao Yongkang 
Published: October 2007

AbstractA series of physically crosslinked complex hydrogels of poly(vinyl alcohol) (PVA) and sodium carboxymethylcellulose (CMC) were prepared via physical mixing and a freeze/thaw technique. The morphology of the CMC/PVA complex gels was analyzed with differential scanning calorimetry and wide‐angle X‐ray diffraction. It was found that the crystallinity and melting temperature of the complex gels decreased, whereas the glass‐transition temperature increased, with an increase in the content of CMC. The reswelling of the complex gels was pH‐responsive and relied on the content of CMC and the freeze/thaw cycles. A network structure model of the complex gel was presented. PVA crystalline regions served as physical crosslinks; the interaction between CMC and PVA resulted in intramolecular entanglements. It was also found that the model drug hemoglobin was released completely from the complex hydrogels in 4 h, and its release rate increased with an increase in the content of CMC. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Curing characteristics of urea–formaldehyde resin in the presence of various amounts of wood extracts and catalysts
Authors: Gao Zhenhua , Wang Xiang‐Ming , Wan Hui , Liu Yu 
Published: October 2007

AbstractThe characteristics of urea–formaldehyde (UF) resin curing in the presence of wood extracts and a catalyst [ammonium chloride (NH4Cl)] were investigated by differential scanning calorimetry (DSC). The effects of extracts from 16 wood species on resin curing behaviors were evaluated. A model developed in this study, Tp = 53.296 exp(−9.72C) + 93.104, could be used to predict the resin curing rate in terms of the DSC peak temperature (Tp) as influenced by the NH4Cl content (C). The results indicated that the curing rate of UF resin increased as the catalyst content increased and reached a maximum when the catalyst content ranged from 0.5 to 1.0% (solid basis over liquid UF resin weight). Further increases in the catalyst content had no effect on the resin curing rate. The curing rates of UF resin in the presence of wood extracts increased with decreased pH values or increased base buffer capacities. It was also discovered that the activation energy could not fully explain the resin curing behavior when some species of wood extracts were present, and therefore, the pre‐exponential factor had to be taken into account. The concept of the equivalent catalyst content (ECC) of wood extracts to the NH4Cl content was introduced in this study; ECCs ranged from 0.0022 to 0.0331% among the 16 wood species. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Bonding Analysis of N‐Heterocyclic Carbene Tautomers and Phosphine Ligands in Transition‐Metal Complexes: A Theoretical Study
Authors: Tonner Ralf , Heydenrych Greta , Frenking Gernot 
Published: October 2007

AbstractDFT calculations at the BP86/TZ2P level were carried out to analyze quantitatively the metal–ligand bonding in transition‐metal complexes that contain imidazole (IMID), imidazol‐2‐ylidene (nNHC), or imidazol‐4‐ylidene (aNHC). The calculated complexes are [Cl4TM(L)] (TM=Ti, Zr, Hf), [(CO)5TM(L)] (TM=Cr, Mo, W), [(CO)4TM(L)] (TM=Fe, Ru, Os), and [ClTM(L)] (TM=Cu, Ag, Au). The relative energies of the free ligands increase in the order IMID<nNHC<aNHC. The energy levels of the carbon σ lone‐pair orbitals suggest the trend aNHC>nNHC>IMID for the donor strength, which is in agreement with the progression of the metal–ligand bond‐dissociation energy (BDE) for the three ligands for all metals of Groups 4, 6, 8, and 10. The electrostatic attraction can also be decisive in determining trends in ligand–metal bond strength. The comparison of the results of energy decomposition analysis for the Group 6 complexes [(CO)5TM(L)] (L=nNHC, aNHC, IMID) with phosphine complexes (L=PMe3 and PCl3) shows that the phosphine ligands are weaker σ donors and better π acceptors than the NHC tautomers nNHC, aNHC, and IMID.